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[iterator] strided, recursive variants
by Jeremy Murphy 28 May '16

28 May '16

Dear Boosters, I was wondering why a strided iterator has not made it into the Boost.Iterator library? There is a strided range in Boost.Range based on a private implementation of such an iterator, and Boost.Compute has their own implementation too. Just an untied loose end? On a related note, what about variants of such iterators that work in recursive algorithms? That is, if you stride a strided iterator, existing implementations will keep nesting the stride type, which the compiler fails to do recursively because there is no stopping criterion. So I wrote a variant of strided iterator that when you stride a strided iterator, it just multiplies the two strides together and takes the base pointer type from the original strided iterator. I assume some of the other iterator adaptors are limited in the same way. Anyway, it's no big deal to me, but I just thought I'd canvas whether that's something people (especially the maintainers) are interested in? Cheers. Jeremy

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compiling mysql-5.7.12, cannot use DTRACE
by Mariano Apilado 26 May '16

26 May '16

Hi, I get the following error when compiling mysql-5.7.12 on Nexenta 4.0.4 OS ( Formerly known as Open Solaris / Illumos ). To temporarily bypass this problem, I chose not to use DTRACE with the compiler options. However, it should be fixed to use DTRACE. # cmake -DENABLE_DTRACE=0 Thanks and Regards,Mariano [ 15%] Linking CXX static library libmysys_ssl.a cd /usr/local/mysql-5.7.12/mysys_ssl && /usr/local/bin/cmake -P CMakeFiles/mysys_ssl.dir/cmake_clean_target.cmake cd /usr/local/mysql-5.7.12/mysys_ssl/CMakeFiles/mysys_ssl.dir && /usr/local/bin/cmake -DDTRACE=/usr/sbin/dtrace -DOUTFILE=/usr/local/mysql-5.7.12/mysys_ssl/CMakeFiles/mysys_ssl.dir/mysys_ssl_dtrace.o -DDFILE=/usr/local/mysql-5.7.12/include/probes_mysql.d -DDTRACE_FLAGS=-64 -DDIRS=. -DTYPE=STATIC_LIBRARY -P /usr/local/mysql-5.7.12/cmake/dtrace_prelink.cmake dtrace: failed to link script /usr/local/mysql-5.7.12/include/probes_mysql.d: No probe sites found for declared provider cd /usr/local/mysql-5.7.12/mysys_ssl && /usr/local/bin/cmake -E cmake_link_script CMakeFiles/mysys_ssl.dir/link.txt --verbose=1 /usr/bin/ar qc libmysys_ssl.a CMakeFiles/mysys_ssl.dir/crypt_genhash_impl.cc.o CMakeFiles/mysys_ssl.dir/mf_tempdir.cc.o CMakeFiles/mysys_ssl.dir/my_default.cc.o CMakeFiles/mysys_ssl.dir/my_getopt.cc.o CMakeFiles/mysys_ssl.dir/my_aes.cc.o CMakeFiles/mysys_ssl.dir/my_sha1.cc.o CMakeFiles/mysys_ssl.dir/my_sha2.cc.o CMakeFiles/mysys_ssl.dir/my_md5.cc.o CMakeFiles/mysys_ssl.dir/my_rnd.cc.o CMakeFiles/mysys_ssl.dir/my_murmur3.cc.o CMakeFiles/mysys_ssl.dir/my_aes_yassl.cc.o /usr/bin/ranlib libmysys_ssl.a cd /usr/local/mysql-5.7.12/mysys_ssl && /usr/bin/ar r /usr/local/mysql-5.7.12/mysys_ssl/libmysys_ssl.a /usr/local/mysql-5.7.12/mysys_ssl/CMakeFiles/mysys_ssl.dir/mysys_ssl_dtrace.o ar: cannot open /usr/local/mysql-5.7.12/mysys_ssl/CMakeFiles/mysys_ssl.dir/mysys_ssl_dtrace.o: No such file or directory ar: /usr/local/mysql-5.7.12/mysys_ssl/CMakeFiles/mysys_ssl.dir/mysys_ssl_dtrace.o not found gmake[2]: *** [mysys_ssl/libmysys_ssl.a] Error 1 gmake[2]: *** Deleting file `mysys_ssl/libmysys_ssl.a' gmake[2]: Leaving directory `/usr/local/mysql-5.7.12' gmake[1]: *** [mysys_ssl/CMakeFiles/mysys_ssl.dir/all] Error 2 gmake[1]: Leaving directory `/usr/local/mysql-5.7.12’ gmake: *** [all] Error 2

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Call for Papers for Meeting C++ 2016 ends on Friday night!
by Jens Weller 25 May '16

25 May '16

Hello Boost Community! a short reminder, that the deadline is coming up for submitting your talk to this years Meeting C++ conference! Meeting C++ 2016 Page: http://meetingcpp.com/index.php/mcpp2016.html Talk submission page: https://meetingcpp.com/mcpp/submittalk/ thanks, Jens Weller

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Error while compiling mysql-5.7.12 /usr/xpg4/include/term.h:596: error: conflicting types for ‘tgoto’
by Mariano Apilado 25 May '16

25 May '16

Hi, I get the following error when compiling mysql-5.7.12 on Nexenta 4.0.4 OS ( Formerly known as Open Solaris / Illumos ). In order to temporarily bypass this problem, I commented out. However, this is not the solution. /usr/local/mysql-5.7.12/cmd-line-utils/libedit/terminal.c:60: /* *#ifdef HAVE_CURSES_H *#include <curses.h> *#elif HAVE_NCURSES_H *#include <ncurses.h> *#endif */ Thanks and Regards,Mariano Error: [ 4%] Building C object cmd-line-utils/libedit/CMakeFiles/edit.dir/terminal.c.o cd /usr/local/mysql-5.7.12/cmd-line-utils/libedit && /usr/bin/gcc -DHAVE_CONFIG_H -D_FILE_OFFSET_BITS=64 -D_POSIX_PTHREAD_SEMANTICS -D_PTHREADS -D_REENTRANT -D__EXTENSIONS__ -I/usr/local/mysql-5.7.12/cmd-line-utils/libedit -I/usr/local/mysql-5.7.12/include -I/usr/local/mysql-5.7.12/extra/rapidjson/include -I/usr/local/mysql-5.7.12/libbinlogevents/include -I/usr/local/mysql-5.7.12/libbinlogevents/export -I/usr/xpg4/include -m64 -O3 -g -fabi-version=2 -fno-omit-frame-pointer -fno-strict-aliasing -DDBUG_OFF -fPIC -m64 -lstdc++ -R'RIGIN/../lib' -R/usr/lib/amd64 -o CMakeFiles/edit.dir/terminal.c.o -c /usr/local/mysql-5.7.12/cmd-line-utils/libedit/terminal.c In file included from /usr/xpg4/include/curses.h:43, from /usr/local/mysql-5.7.12/cmd-line-utils/libedit/terminal.c:60: /usr/xpg4/include/term.h:596: error: conflicting types for ‘tgoto’ /usr/local/mysql-5.7.12/cmd-line-utils/libedit/sys.h:137: note: previous declaration of ‘tgoto’ was here gmake[2]: *** [cmd-line-utils/libedit/CMakeFiles/edit.dir/terminal.c.o] Error 1 gmake[2]: Leaving directory `/usr/local/mysql-5.7.12' gmake[1]: *** [cmd-line-utils/libedit/CMakeFiles/edit.dir/all] Error 2 gmake[1]: Leaving directory `/usr/local/mysql-5.7.12’ gmake: *** [all] Error 2

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Having problems installing mysql 5.7.12 with boost ELF 32 bit, wrong ELF Class
by Mariano Apilado 25 May '16

25 May '16

Hi, I get the following error when compiling mysql-5.7.12 on Nexenta 4.0.4 OS ( Formerly known as Open Solaris / Illumos ). How do I fix the compile options or get the necessary files required to make the compile successful? Thanks and Regards, Mariano The files libboost_system.so and libboost_chrono.so are the wrong ELF class: ELFCLASS32. root@nex-01-test:/volumes# file /root/boost_1_59_0/stage/lib/libboost_system.so /root/boost_1_59_0/stage/lib/libboost_system.so: ELF 32-bit LSB dynamic lib 80386 Version 1, dynamically linked, not stripped, no debugging information available root@nex-01-test:/volumes# file /root/boost_1_59_0/stage/lib/libboost_system.so /root/boost_1_59_0/stage/lib/libboost_system.so: ELF 32-bit LSB dynamic lib 80386 Version 1, dynamically linked, not stripped, no debugging information available Error Message: [ 95%] Linking CXX executable ../mysqlpump cd /root/mysql-5.7.12/client/dump && /usr/local/bin/cmake -E cmake_link_script CMakeFiles/mysqlpump.dir/link.txt --verbose=1 /usr/bin/g++ -w -fpermissive -m64 -Wall -Wextra -Wformat-security -Wvla -Woverloaded-virtual -Wno-unused-parameter -O3 -g -fabi-version=2 -fno-omit-frame-pointer -fno-strict-aliasing -DDBUG_OFF -R'$ORIGIN/../lib' -R/usr/lib/amd64 CMakeFiles/mysqlpump.dir/program.cc.o -o ../mysqlpump libmysqlpump_lib.a -lboost_system -lboost_chrono ../base/libclient_base.a ../../libmysql/libmysqlclient.a -lsocket -lnsl -lm ../../extra/liblz4_lib.a ld: fatal: file /root/boost_1_59_0/stage/lib/libboost_system.so: wrong ELF class: ELFCLASS32 ld: fatal: file /root/boost_1_59_0/stage/lib/libboost_chrono.so: wrong ELF class: ELFCLASS32 ld: fatal: file processing errors. No output written to ../mysqlpump collect2: ld returned 1 exit status gmake[2]: *** [client/mysqlpump] Error 1 gmake[2]: Leaving directory `/root/mysql-5.7.12' gmake[1]: *** [client/dump/CMakeFiles/mysqlpump.dir/all] Error 2 gmake[1]: Leaving directory `/root/mysql-5.7.12’ gmake: *** [all] Error 2

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[compute] [OS X 10.11.5] [GeForce GT 750M] Segmentation fault
by Prashant 25 May '16

25 May '16

Hi, Am trying to sort a vector on GPU (GeForce GT 750M) using example code which generates SEGV. However, it runs fine on Iris Pro (Intel(R) Core(TM) i7-4850HQ CPU). We observe SEGV when size is 10 million. When the size is 5 million, following exception is thrown: boost/1_61_0/include/boost/compute/command_queue.hpp(453): Throw in function boost::compute::event boost::compute::command_queue::enqueue_write_buffer(const boost::compute::buffer &, size_t, size_t, const void *, const boost::compute::wait_list &) Dynamic exception type: boost::exception_detail::clone_impl<boost::exception_detail::error_info_injector< boost::compute::opencl_error> > std::exception::what: Invalid Value Another observation: if the size of vector is 50 million the sorting works fine, though the timings are worse than Iris Pro. Also, when is size is 100 million, the binary causes the OS to crash. Compiler details: clang++ --version Apple LLVM version 7.3.0 (clang-703.0.31) Target: x86_64-apple-darwin15.5.0 Thread model: posix OS: System Version: OS X 10.11.5 (15F34) Kernel Version: Darwin 15.5.0 Regards, Prashant ----------------------------Cut here------------------------------------- #include <iostream> #include <vector> #include <algorithm> #include <boost/foreach.hpp> #include <boost/compute/core.hpp> #include <boost/compute/platform.hpp> #include <boost/compute/algorithm.hpp> #include <boost/compute/container/vector.hpp> #include <boost/compute/functional/math.hpp> #include <boost/compute/types/builtin.hpp> #include <boost/compute/function.hpp> #include <boost/chrono/include.hpp> #include <boost/exception/all.hpp> namespace compute = boost::compute; int main(int argc, char* argv[]) { if (argc != 2) { std::cout << "Usage: " << argv[0] << " <size> " << std::endl; return 0; } // generate random data on the host std::vector<float> host_vector(atoi(argv[1])); std::generate(host_vector.begin(), host_vector.end(), rand); std::cout << "===============CPU==================\n"; for (size_t k=0; k<5; k++) { std::vector<float> host_copy_vector(host_vector); auto start = std::chrono::high_resolution_clock::now(); std::sort(host_copy_vector.begin(), host_copy_vector.end()); auto duration = std::chrono::duration_cast<std::chrono::milliseconds> (std::chrono::high_resolution_clock::now() - start); std::cout << "time: iteration ("<< k << ") : " << duration.count() << " ms" << std::endl; } std::vector<compute::platform> platforms = compute::system::platforms(); for(size_t i = 0; i < platforms.size(); i++){ const compute::platform &platform = platforms[i]; std::cout << "Platform '" << platform.name() << "'" << std::endl; std::vector<compute::device> devices = platform.devices(); for(size_t j = 0; j < devices.size(); j++){ const compute::device &device = devices[j]; std::string type; if(device.type() & compute::device::gpu) type = "GPU Device"; else if(device.type() & compute::device::cpu) type = "CPU Device"; else if(device.type() & compute::device::accelerator) type = "Accelerator Device"; else type = "Unknown Device"; if (type != "GPU Device") { std::cout << "Ignoring non GPU devices.\n"; continue; } std::cout << "====\n"; std::cout << " " << type << ": " << device.name() << std::endl; std::cout << "====\n"; compute::context context(device); compute::command_queue queue(context, device); for (size_t k=0; k<5; k++) { compute::vector<float> device_vector(host_vector.size(), context); // copy data from the host to the device compute::copy( host_vector.begin(), host_vector.end(), device_vector.begin(), queue ); auto start = std::chrono::high_resolution_clock::now(); try { compute::sort(device_vector.begin(), device_vector.end(), queue); } catch (boost::exception & e) { std::cerr << diagnostic_information(e); break; } auto duration = std::chrono::duration_cast<std::chrono::milliseconds> (std::chrono::high_resolution_clock::now() - start); std::cout << "time: iteration ("<< k << ") : " << duration.count() << " ms" << std::endl; } std::cout << "====\n"; } } return 0; }

2 1

[multiprecision] compilation failure
by Raffi Enficiaud 24 May '16

24 May '16

Hi, I have the following failure on develop from multiprecision (unit tests of boost.test): In file included from writing-test-ts/fp-multiprecision-comparison-test.cpp:23:0: ../../../boost/multiprecision/cpp_dec_float.hpp: In member function ?std::size_t boost::multiprecision::backends::cpp_dec_float<Digits10, ExponentType, Allocator>::hash() const?: ../../../boost/multiprecision/cpp_dec_float.hpp:264:10: error: ?hash_combine? is not a member of ?boost? boost::hash_combine(result, data[i]); Thanks, Raffi

3 2

Request for a "Policy Review" regarding 'CMakeLists.txt'
by David Sankel 24 May '16

24 May '16

A question has been brought up regarding whether or not a Boost library author is permitted to include a 'CMakeLists.txt' file in the root of the directory. This stemmed from a discussion at C++Now 2016 which included several members of the Boost Steering Committee and a sampling of the Boost community. We recommend and propose that the Boost Guidelines are modified to allow library authors, at their own discretion, to include a 'CMakeLists.txt' file in their library's top-level directory. * Several libraries, such as Boost.Hana and Boost.Spirit, have two distribution mechanisms: one as distributed with Boost and the other as an independent package. The requirement that these libraries not include a 'CMakeLists.txt' as part of their Boost distribution creates a maintenance burden for authors or otherwise hurts usability of the independent distribution. * Several companies have revealed that they are building Boost with their own custom CMake scripts. The suggested policy change would enable authors to relieve the infrastructure cost of their CMake users and unify how their library is built. * CMake is, by far, the most popular build system for C++. Allowing authors to support CMake users in addition to BJam will help the Boost ecosystem to grow and thrive by lowering the barriers to access. -- David Sankel

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Boost.Fit review Mars 3-20 result
by Vicente J. Botet Escriba 24 May '16

24 May '16

Hi, I will be out for two weeks and I wanted to at least give the result of the Boost.Fit library review even if I would need more time to have a complete report. Summary ======= The review of the proposed Boost.Fit library ended on Mars 20, 2016. The verdict is: Conditional acceptance (a new review is needed) There were too much concerns about the documentation and what exactly this library is proposing and not enough reviews commenting the design, code and test for each one of the proposed functions. From the review discussion I deduce that there is some interest in the library, and that some people don't understand yet what the library is proposing. Paul has started already to take in account some if the issues raised during the review and a lot of them must be resolved before we re-try a new review. There were some discussion about the name of the library, but there were no consensus. Paul is free to change the name of his library and see how people react. On behalf of the Boost community, I would like to thank Paul Fultz for the work he has put into the Fit library so far. I encourage him to continue to evolve this library and to bring it back for a new review. We had seven 6 formal votes, and 2 more votes without a complete review abbreviated here: Steaven Watanabe: No in his current state Zach Laine : Conditinal acceptance Krzysztof Jusiak: Accepted Artyom Beilis : Rejected Peter Dimov : Accepted (no review) Manuel Sancher : Accepted (no review) Rob Stewart : Conditinal acceptance ??? Louis Dionne : Conditinal acceptance There were other people that participated on the review giving their advice respect to a specific issue. I thank each of these reviewers, and indeed everyone who invested some time participating in the discussions. If you feel that I have misrepresented your position, or have omitted or garbled an important point, please respond: the archived mail thread should accurately reflect the will of the community, even if this message does not. Detailed Report =============== You will need to wait yet for a month before I will be able to do it. On the mean time there are a lot of issues that must be addressed and that are part of the github issues. For more information see: Github:https://github.com/pfultz2/Fit/tree/boost Issues:https://github.com/pfultz2/Fit/issues Documentation:http://pfultz2.github.io/Fit/doc/html/ Hopping this helps, Vicente Botet Escriba

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b2 looks for tools/inspect/build/Jamfile
by Peter Dimov 23 May '16

23 May '16

I'm experimenting with a partial Boost clone, the superproject, tools/build, libs/bind, libs/config and few others, and when trying to build the tests, I'm getting the following error: D:\tmp\boost\libs\bind\test>..\..\..\b2 toolset=msvc-10.0 D:/tmp/boost/tools/build/src/build\project.jam:262: in find-jamfile from module project error: Unable to load Jamfile. error: Could not find a Jamfile in directory '../../../tools/inspect/build'. error: Attempted to find it with pattern '[Bb]uild.jam [Jj]amfile.v2 [Jj]amfile [Jj]amfile. [Jj]amfile.jam'. error: Please consult the documentation at 'http://www.boost.org'. D:/tmp/boost/tools/build/src/build\project.jam:280: in load-jamfile from module project D:/tmp/boost/tools/build/src/build\project.jam:64: in load from module project D:/tmp/boost/tools/build/src/build\project.jam:89: in load-used-projects from mo dule project D:/tmp/boost/tools/build/src/build\project.jam:75: in load from module project D:/tmp/boost/tools/build/src/build\project.jam:113: in load-parent from module p roject D:/tmp/boost/tools/build/src/build\project.jam:464: in initialize from module pr oject D:/tmp/boost/tools/build/src/build\project.jam:306: in load-jamfile from module project D:/tmp/boost/tools/build/src/build\project.jam:64: in load from module project D:/tmp/boost/tools/build/src/build\project.jam:113: in load-parent from module p roject D:/tmp/boost/tools/build/src/build\project.jam:464: in initialize from module pr oject D:/tmp/boost/tools/build/src/build\project.jam:306: in load-jamfile from module project D:/tmp/boost/tools/build/src/build\project.jam:64: in load from module project D:/tmp/boost/tools/build/src/build\project.jam:145: in project.find from module project D:/tmp/boost/tools/build/src\build-system.jam:535: in load from module build-sys tem D:\tmp\boost\tools\build\src/kernel\modules.jam:295: in import from module modul es D:\tmp\boost\tools\build\src/kernel/bootstrap.jam:139: in boost-build from modul e D:\tmp\boost\boost-build.jam:17: in module scope from module Does anyone have an idea why b2 looks for the tools/inspect Jamfile? I don't remember this being a problem before when I tried a stripped-down installation.

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doctest - the lightest feature rich C++ single header testing framework - if it can enter boost and if it/boost will benefit from that
by Viktor Kirilov 23 May '16

23 May '16

Hello! I just released doctest - https://github.com/onqtam/doctest All the info about it can be found on github. So do you think it can enter the boost project? How much work will it take to get it into boost except for adding boost in the title? Will it or boost benefit from that addition? Also I've sort-of followed the Best Practice Handbook (I consider it very valuable) as much as possible - https://svn.boost.org/trac/boost/wiki/BestPracticeHandbook Any feedback will be greatly appreciated. Thanks!

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Rebooting Boost: Call for Lightning Talks @ CppCon
by Niall Douglas 23 May '16

23 May '16

At C++ Now a number of informal meetings showed there to be frustrations with the current ecosystem around the Boost C++ Libraries (to paraphrase a founder of Boost, "Boost is supposed to serve *the entire C++ community; it isn't Boost's goal to serve Boost's community*". Recent and recurrent boost-dev discussions have raised the lack of cmake based tooling; lack of ABI management and the consequent ODR violation when mixing Boost versions in the same process; the anti-social behaviour of Boost towards library end users, new ideas, new blood and the wider C++ community; and the chronic lack of maintenance of up to half the Boost libraries. One question which needs to be answered is whether a clean reboot of Boost from the first principles of proving high quality C++ libraries well suited for use with the latest C++ standard is viable. This new collection of C++ libraries would be started completely from scratch (even if some existing libraries were ported into the new organisation), so ANYTHING is possible. All we need is a critical mass of library developers willing to collaborate on developing a shared infrastructure mutually beneficial to all participants, whether library developer or library end user. To that end of discovering if this critical mass is there, five minute lightning talk topics are requested for CppCon this September on this topic: "What design pattern, practice or idiom should a standards aspiring collection of C++ 14/17 libraries share?" Please keep each talk topic focused on a single design pattern, practice or idiom (see suggested talk format below). Each speaker may submit up to THREE talk topics (not all may be accepted if there are a lack of slots, so please rank them in order of preference). Please send your talk topics to me privately by email, only if sufficient numbers present to fill a session will your name and your talk topic be shared with the CppCon Programme Committee. We'll try to arrange a short panel session at the end so attendees can ask questions of the speakers. After the lightning talk we'll arrange a restaurant so all the speakers and any interested attendees can dine together, followed by a night in a Bellevue bar. If after the dust has settled it is felt there is a critical mass sufficient to reboot a brand shiny new edition of Boost, we'll start development! I should *stress* that it is up to the CppCon Programme Committee whether these lightning talks are approved or not. I'll just copy and paste your proposed talk to the CppCon PC as-is. If insufficient lightning talk topics are received by me to fill a 60 minute session, I'll withdraw this talk proposal from CppCon. Suggested talk format ================ Five minutes is not much time, so here is a suggested lightning talk outline: 1. A current widely practiced library design pattern (show example). 2. The problems it generates for library users or maintainers. 3. Your proposed alternative design pattern (show example). 4. The problems the alternative design pattern fixes. 5. Any mockup, prototype or even live demo (!) of the alternative design pattern in action. Suggested talk themes might be documentation, packaging, distribution, testing, tooling, quality assessment, barriers to entry, governance, strategy, important gaps in the standard libraries, automation and deprecation/removal policies. Here is an example of such a lightning talk: 1. Current design pattern: Library v1.00: namespace boost { namespace lib { void foo(size_t, char); } } User code: boost::lib::foo(100, 'n'); 2. Problem: Library v1.01: namespace boost { namespace lib { void foo(char, size_t); } } User code: boost::lib::foo(100, 'n'); // oh oh! 3. Alternative: Library v1.00: namespace boost { namespace lib { inline namespace v100 { void foo(size_t, char); } } } #define BOOST_LIB_NAMESPACE_V100 boost::lib::v100 Library v1.01: namespace boost { namespace lib { inline namespace v101 { void foo(char, size_t); } } } #define BOOST_LIB_NAMESPACE_V101 boost::lib::v101 User code: // Mount v100 of Boost.Lib into "lib" namespace lib=BOOST_LIB_NAMESPACE_V100; lib::foo(100, 'n'); // ABI stable! No ODR violation possible! 4. Problems fixed: a) Mixing incompatible versions of individual Boost libraries in the same process (or even translation unit) is now safe. b) Libraries can now depend on other libraries without worrying about breaking code which depends on them which uses a different version of the same dependency. This greatly helps reduce change ripple effects. c) Forward compatibility or alternative implementation shims are now very easy to implement e.g. library users can externally configure either Boost.Filesystem or std::experimental::filesystem for your library to use, your code simply refers to _some_ Filesystem TS implementation e.g. namespace filesystem = FILESYSTEM_TS_IMPLEMENTATION; filesystem::path mypath; -- ned Productions Limited Consulting http://www.nedproductions.biz/ http://ie.linkedin.com/in/nialldouglas/

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@boost-admins: permission to git-repo removed?!
by Oliver Kowalke 23 May '16

23 May '16

Hi, I can't push commits to git-repo boost.coroutine2: remote: Invalid username or password. fatal: Authentication failed for 'https://github.com/boostorg/coroutine2/' Could you please re-add user 'olk', please. thx, Oliver

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What C++14/1z standard or TS libraries would you like to have available on a C++11 compiler?
by Vicente J. Botet Escriba 23 May '16

23 May '16

Hi, I would like to have your feedback on C++ standard library features you would like to have available for a C++11 compiler. The idea would be to present a Boost.StdExtensions library that would provide some of these features for review with some of these features. Please , let me know if you are interested in participating in this project and working on some specific parts. This library should avoid as much Boost dependencies as possible. How the library could be structured? I believe that it should follow the C++ standard files. Which folder should be used? boost/stdext? boost/stdext11? Which namespace? boost::stdext? I have prefixed with a * the lines that interest myself and with VBE* those that I could work on. The features that need compiler help or that need C++14/17 language features are excluded and prefixed by N/A. Please be free to add a * if you are interested and your name as well if you want to participate. Best, Vicente P.S. The project could be as well extended to C++98 compilers with C++11 standard libraries (But I would not have time to invest in). P.S.S. I would also be interested in extend the project to extended to C++14 compilers. C++14 standard libraries ================ VBE* N3658 - Compile-time integer sequences * N3654 - Quoted Strings N3656 - make_unique VBE* N3462 - std::result_of and SFINAE * N3668 std::exchange() N3469 Constexpr Library Additions: chrono N3470 Constexpr Library Additions: containers N3471 Constexpr Library Additions: utilities N3302 Constexpr Library Additions: complex VBE* N3545 An Incremental Improvement to integral_constant N3644 Null Forward Iterators N3670 Addressing Tuples by Type N3671 Making non-modifying sequence operations more robust N3642 User-defined Literals VBE* N3655 TransformationTraits Redux (excluding part 4) N3657 Adding heterogeneous comparison lookup to associative containers N3669 Fixing constexpr member functions without const N3659 Shared Locking in C++ N3779 User-defined Literals for std::complex N3789 Constexpr Library Additions: functional N3887 Consistent Metafunction Aliases N3891 A proposal to rename shared_mutex to shared_timed_mutex C++1z standard libraries ================ VBE* N3911 TransformationTrait Alias void_t N4089 Safe conversions in unique_ptr<T[]> VBE* N4169 A proposal to add invoke function template N4258 Cleaning-up noexcept in the Library. N4277 TriviallyCopyable reference_wrapper. N4279 Improved insertion interface for unique-key maps. VBE* N4280 Non-member size() and more N4284 Contiguous Iterators. N4387 improving pair and tuple VBE* N4389 bool_constant N4508 shared_mutex for C++17 N4366 LWG 2228 missing SFINAE rule N4510 Minimal incomplete type support for standard containers N/A* P0006R0 Adopt Type Traits Variable Templates for C++17. VBE* P0092R1 Polishing <chrono> VBE* P0007R1 Constant View: A proposal for a std::as_const helper function template. VBE* P0156R0 Variadic lock_guard(rev 3). P0074R0 Making std::owner_less more flexible VBE* P0013R1 Logical type traits rev 2 P0024R2 The Parallelism TS Should be Standardized P0226R1 Mathematical Special Functions for C++17 VBE* P0220R1 Adopt Library Fundamentals V1 TS Components for C++17 P0218R1 Adopt the File System TS for C++17 P0033R1 Re-enabling shared_from_this VBE* P0005R4 Adopt not_fn from Library Fundamentals 2 for C++17 P0152R1 constexpr atomic::is_always_lock_free N/A* P0185R1 Adding [nothrow-]swappable traits P0253R1 Fixing a design mistake in the searchers interface P0025R0 An algorithm to "clamp" a value between a pair of boundary values P0154R1 constexpr std::hardware_{constructive,destructive}_interference_size P0030R1 Proposal to Introduce a 3-Argument Overload to std::hypot P0031R0 A Proposal to Add Constexpr Modifiers to reverse_iterator, move_iterator, array and Range Access P0272R1 Give std::string a non-const .data() member function VBE* P0077R2 is_callable, the missing INVOKE related trait Fundamental V1 TS ============ Uses-allocator construction Changes to std::shared_ptr and weak_ptr Additions to std::function Additions to std::promise Additions to std::packaged_task Class erased_type VBE* Calling a function with a tuple of arguments N/A Type traits (_v) Other type transformations Compile-time Rational Arithmetic Time Utilities System Error Support Class memory_resource Class template polymorphic_allocator Template alias resource_adaptor Global memory resources Pool resource classes Class monotonic_buffer_resource Alias templates using polymorphic memory resource Searchers * Optional Objects Initial implementation * class any * string_view memory Algorithms library

6 8

Boost 1.61.0 has been released
by Rene Rivera 22 May '16

22 May '16

Release 1.61.0 of the Boost C++ Libraries is now available. These open-source libraries work well with the C++ Standard Library, and are usable across a broad spectrum of applications. The Boost license encourages both commercial and non-commercial use. This release contains four new libraries and numerous enhancements and bug fixes for existing libraries. New Libraries * Compute: Parallel/GPU-computing library, from Kyle Lutz. * DLL: Library for comfortable work with DLL and DSO, from Renato Tegon Forti and Antony Polukhin * Hana: A modern C++ metaprogramming library, from Louis Dionne. * Metaparse: A library for generating compile time parsers parsing embedded DSL code as part of the C++ compilation process, from Abel Sinkovics. For details, including download links, see http://www.boost.org/users/news/version_1.61.0 You can also download directly from SourceForge: http://sourceforge.net/projects/boost/files/boost/1.61.0/ Tom Kent has made pre-built windows binaries, and they are available at: https://sourceforge.net/projects/boost/files/boost-binaries/1.61.0/ To install this release on your system, see http://www.boost.org/doc/libs/release/more/getting_started/index.html Thanks, --The Boost release team Vladimir Prus Rene Rivera Marshall Clow Eric Niebler Daniel James Beman Dawes

11 18

Boost Evolution
by Robert Ramey 21 May '16

21 May '16

What I would like to see is more encouragement for the idea of boost evolution. But I have well defined ideas about how that should occur. I articulated these ideas is quite a bit of detail at C++Now in 2015 to a packed house. It wasn't recorded so you'll have to take my word for it. All is not lost though. For those who might be interested I kept my practice recordings for the narrative on the slides and attached them to each slide. So you can get a good feeling for the presentation by checking out http://www.blincubator.com/C++Now2015/index.html If you do this don't forget to checkout the last two slides (including the audio)! in real life it was much better!!! When I articulated my particular suggestions at the conference there was a lot of push back and I sort of lost control of things. On the other hand, there was a lot of enthusiasm for my "call to action". I didn't expect any drastic changes. But as I look back a year I do see some real progress. I see: a) more and better reviews b) more interest, discussion and criticism of documentation c) 30 libraries in the incubator. Some have already been added to boost. d) Now movement on opening up the build/test system to evolution. e) A program in place to make more resources available for maintaining existing libraries. The complains of unmaintained libraries have diminished by quite a bit - I don't know for a fact that this is related to this program - maybe it's just a happy coincidence. A couple of things have made much progress. a) modular deployment and dependency management. No surprise here as this is a job of major, major difficulty. b) policy for library deprecation - not really hard but really very low priority. c) improvements in incubator - no real progress - but it's probably as good as it needs to be. d) boost website improvement - no discernible progress. There is one big lesson from all this: a) Boost is not a company - we don't take direction from the top. b) Boost is not a government - we actually do something. c) Boost is a religion - want something changed, start preaching. Get other people on board. Convince people people to start doing something. Take a look at the CMake history. There was a huge effort undertaken from the top to switch to CMake for build / test. It was a failure because it tried to do it from the top down. I'm thinking that the promoters of this idea concluded that the problem wasn't ambitious enough and added deployment to the task and built rypll. This had as key collaborators our most capable and hard core developers - including David Abrahams and Eric Neibler. Huge amount of expended effort but not much came out of it. I think if you want to help boost evolve - remember Boost is a religion. We are the jesuits of C++. Bjarn's marines - the tip of the spear. We ambush the world with a new idea which builds or replaces something else. We do it in an insidious manner. The opening up to CMake has proceeded steadily over years until it's a the cusp of victory. No one saw it coming and here it is. The world doesn't change from great initiatives, it changes when the old order collapses while espending it's existence to deny change. I've been told on this is a right wing world view - and so it is - oh well. So I encourage those who want to contribute to Boost and by extension C++ to consider using this approach. I think you'll be more successful. Robert Ramey

19 47

A comment on cmake and subprojects
by Biddiscombe, John A. 20 May '16

20 May '16

In our task of the HBP (Human Brain Project), we have a lot of libraries with interdependencies and have standardised on a reasonably simple system that works well enough – it can/could be improved significantly, but in case it’s of interest to boost, here’s a brief description (which I’m writing from memory and all the actual names of commands etc are wrong, but I only aim to describe the process) A top level cmakelists file would contain something like project(my_big_project) add_subproject(subprojectX ${CMAKE_CURRENT_SOURCE_DIR}/x) add_subproject(subprojectY ${CMAKE_CURRENT_SOURCE_DIR}/y) etc subprojects X,Y,….. Are defined by either including the source for those projects in the relevant subdirs, or by providing an additional command along the lines of git_external_project(name URL branchname/SHA/etc) Or by supplying a .gitprojects file in the root of the master subproject (subproject can if they wish do this recursively) which may contain a list of desirable projects + urls that we know will be needed if enabled When the user runs cmake on the top-level source project (my_big_project) it provides OPTIONS of the form SUBPROJECT X ON/OFF SUBPROJECT Y ON/OFF Which the user can enable via the GUI or by cmake –DSUBPROJECT_X=ON …. The macros defined will decide that if project X is not present to do a git clone (--shallow, --branch, --anything you want to add in the config) of project X,Y,… from the git URL supplied and checkout the repo into the correct location, add_subproject then enters the subproject and cmake progresses as usual. Inside the subproject, another macro can defined DEPENDENCIES of the project via more instantiations of the same kind which will also be cloned as git subprojects if they are not already present (currently if X depends on A branch1 and Y depends on A branch2 we throw an error, but it would be possible to support this tight control of include_directories). Seeing the ongoing discussion of cmake in boost (I am one of the many it seems who cmakeified the parts of boost I needed years ago and then gave up around the time rypll came into being – hoping that the job would be done properly). So the top level boost cmakelists would simple contain a list of all the libraries and their git locations and release branches, each sub project (library) can say dependencies(atomic, filesystem, threads, context) and let the cmake scripts do the rest. A user checking out the “top” level boost would get only a single cmakelists file with a bunch of helper scripts containing the macros needed for install, versions, git cloning etc etc and would then run cmake –DSUBPROJECT_ATOMIC=ON –DSUBPROJECT_THREADS=ON –DSUBPROJECT_CONTEXT=ON ~/path/to/top/level/boost-cmakelists (you could change the SUBPROJECT to BOOSTMODULE or something like that if you preferred) If one of the libs the user ‘wants’ uses another library, it gets enabled by the dependencies declared in the lib and everything just builds and works. A make install will install all the libs that got built including those dependencies that were pulled in (some public/private options could no doubt be added to make that better if necessary). To give you an idea of what I’m referring to, https://github.com/Eyescale/CMake/blob/master/GitExternal.cmake<https://github.com/Eyescale/CMake/blob/master/SubProject.cmake> https://github.com/Eyescale/CMake/blob/master/SubProject.cmake Are a couple of scripts that do some of the work. The process has helped us to simplify somewhat our build and dependency process and it might be a useful mechanism for boost to use cmake. It isn’t perfect, isn’t pretty in some places and has been heavily tweaked beyond its original purpose so the scripts would not be considered usable in their current state – but with some cleaning up … One very nice feature is the one can create a simple script project(mystuff) #set some options we might beed set(boost_optionX,y,x…) add_subproject(boost) # and some more set(hpx_optionX,y,z…) add_subproject(hpx) set(my_optionX,y,z…) add_subproject(stuff_that_needs_them) And the user does not need to worry about cloning the projects as the gitproject refs will do it for them and take what’s needed on a per repo basis. (I use this for HPX extensively - the individual libs/projects must be careful with relative path names and using per project prefixes for options, tests etc etc) I would be happy to volunteer as a helper should you wish for help cmakeifying boost regardless of the method by which you proceed. JB -- John Biddiscombe, email:biddisco @.at.@ cscs.ch http://www.cscs.ch/ CSCS, Swiss National Supercomputing Centre | Tel: +41 (91) 610.82.07 Via Trevano 131, 6900 Lugano, Switzerland | Fax: +41 (91) 610.82.82

1 0

Files in individual libraries
by Edward Diener 20 May '16

20 May '16

As long as library authors follow the normal Boost guidelines for placing the necessary files for using, building ( for non-header only libraries ), testing, and documenting their library I really don't see why an author cannot add to their library whatever other files they want in whatever place in their library structure they want to put it. Can it really be such a big issue that this should not be allowed ? And, if so, why ? If the real issue being objected to is that the placement of additional files gives the end-user an impression that Boost libraries generally support additional things which an individual library supports with the additional files, wouldn't it just be better to encourage and/or require that an individual library developer document the additional files as personal extensions to what Boost requires.

2 2

Re: [boost] [Boost-users] Boost 1.61.0 has been released
by Daniel James 19 May '16

19 May '16

On 18 May 2016 at 08:05, Vladimir Prus <vladimir.prus(a)gmail.com> wrote: > > Tom has pointed a typo in file names in the file. Correct one is now > attached, and instructions > for validating are the same: I added the to the website, it's currently linked from the release notes, and if it's okay, I'll add a link to the download page at some point. Although it can't be underestimated just how little I care or understand about any of this stuff, so I'm sure I've done it all wrong. If line endings make a difference then it might not work since git converted the file to unix style automatically, so let me know. I also don't really want to add all the instructions to the release notes, so if someone wants to write generic instructions for another page, I could put that up and link to it.

1 0

DMARC and mailman
by James Sharpe 19 May '16

19 May '16

In June 2016 gmail is going to be changing its DMARC policy to reject any unaligned mail. This means that we will be seeing any mailing list responses from a gmail.com address to be considered spam by any mail server that enforces DMARC. For a while now yahoo.com has had this policy turned on which has meant that yahoo.com addresses have been considered spam. Mailman has released a workaround in version 2.1.18: https://www.mail-archive.com/mailman-users@python.org/msg64098.html The boost mailing list is currently on mailman 2.1.15. I'd strongly suggest that this should be updated as a matter of urgency else we'll find a lot of the conversations on this list will end up in the spam folder... Regards, James

1 0

Link problem
by Adolfo 19 May '16

19 May '16

Hi everyone, I am quite newbie on this and perhaps this is quite simple, sorry for the trouble. I am using VSC++ 2012, I have the boost version boost_1_60_0 and I have built it following the description in http://www.boost.org/doc/libs/1_60_0/more/getting_started/windows.html. No problem with batch files (bootstrap and b2). When I try to test the example code from section 6, I have the following linking error: Error 1 error LNK1104: no se puede abrir el archivo 'libboost_regex-vc110-mt-gd-1_60.lib' I have realised that in my ...\boost_1_60_0\stage\lib directory, all the .lib files have names like libboost_*-vc140-*-1_60.lib. Can anybody be so kind of telling me what I did wrong or where I have to change this?? Best wishes, Adolfo.

3 2

Re: [boost] [Boost-users] Boost 1.61.0 has been released
by Tom Kent 18 May '16

18 May '16

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 > On Wed, May 18, 2016 at 2:05 AM, Vladimir Prus <vladimir.prus(a)gmail.com> wrote: > > On 17/05/2016 13:16, Vladimir Prus wrote: > > > On 13/05/2016 15:07, Rene Rivera wrote: > > > Release 1.61.0 of the Boost C++ Libraries is now available. > > > > > > For details, including download links, see http://www.boost.org/users/news/version_1.61.0 > > > > > > You can also download directly from SourceForge: http://sourceforge.net/projects/boost/files/boost/1.61.0/ > > > > You can optionally verify integrity of the source downloads using the attached signed checksums file. > > Tom has pointed a typo in file names in the file. Correct one is now attached, and instructions > for validating are the same: I now get good hashes and a good signature verification. I'm signing this email with my private key "Thomas Kent <teeks99(a)yahoo.com>" for the record. Tom Original Attachment: - -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 a547bd06c2fd9a71ba1d169d9cf0339da7ebf4753849a8f7d6fdb8feee99b640 boost_1_61_0.tar.bz2 a77c7cc660ec02704c6884fbb20c552d52d60a18f26573c9cee0788bf00ed7e6 boost_1_61_0.tar.gz fa1c34862b7ba8674ed6e064a14667a11830c6252f702d9458451834b74f7815 boost_1_61_0.7z 02d420e6908016d4ac74dfc712eec7d9616a7fc0da78b0a1b5b937536b2e01e8 boost_1_61_0.zip - -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAEBCAAGBQJXPBG3AAoJEA8aPs1OrCMWL1QQAJCsQbr4rxpQMDssW5O0Fupg aw8Us0CnfPLSPW5gMdQoIQxu/n1SNobn4Vg1/hyTfweufqFwHFRxJnHiWtlbI/GB q1TueLPCxcJUi6lT7ZOVcpKb6AS6vOnSJRODQ0zk62phKBmLDUxiBI46FlCkzHbz uWVG+wttzk2Skeb3400xWEMtM0fgX3oJenh5Ye//oD7biJC0aIVPrnkauQ2Nze0l 2nG8e7w7ZzlXEx0Ei8KHiyBsFMj0/O5JIJKbxWorBAeELSgWun0YqB9EnrbADGDp XCEUUg1FB2llTmpG3a/dyv8fMlAS/ENka7e4aGuIHAlyfmTKGx+9Zd813XLiSjvw CHCyp+b7v0dGn2RFrVhgl9qRyFKgcvYjhhsA42iO0eFt7rgkoXV72qQzjSClzjkS jJrcj8dxJkZVMJ9tWKCmzGoPYRj4z8Nt8dw7HDqFGb7/2Rw6FZ18N9SsqHD+y9G3 TZhPPYQJVqckM9qo0CFzYwZpjiBgLhhQI6iEUh8UB8xXB09cJfgHGvyszXsvR+3l xQvKq19BYWHlPoi4Ie+YUzxF81Pgj98mbnwXLcgUoLBZWueXGfFdf+nBvyDoQyli LbHEpt0cGwWyfk+HXt+Qa5dmSRMr7zZpmWseBr9/6J1gCoNxAEOqHZ1hCrpFIHWt pM+LHXktogy3CpBV2IXH =6T/2 - -----END PGP SIGNATURE----- -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJXPIMxAAoJEO5CwwL7YZSoqjQQAME+iTB9MhE3Jz2AAl7+tohB +v8U25f1C2X6qbVTKCynG+FzdfthIOwdLeReIcY8fUD7O30LqhYpfjPgDJvRqvDT pjU/jxD4ORLn9aEtNGcEX+EtSuO9dV2eZP3cDcyNnTRUu26O6LkJN2wRb2BFa1kN coVuhNSD7I8BBpiNgWo/J09Ajv3GRags8y6WHjC6IUD5isGUGMGD7udhjD6qcX/q hiyTfdzkqMo5lDmGj20JCsuXg1Iqku5JKydeDH4vunpZokbDmtSja992kzMSRFGK CemHapPcml5ei8ubvEnROYLPcIpcrL9zpO6vTpKRQs5dzfJDkeiCeS9Zgvm/fb7h G4yoUD08ccU0HHwRVCNdpHXPRgSSh3JJp94XuWO/sFgNg0q+5pGeGoqnveBaroqu zAgdcteBmw+YoU39bWt+kPu5zVbVygHZNXpC0BOKc8+IP86wwOvEHDEUm1o5UQma QPWQrZuoMcGNE9SZn1K1Zg+oJ6KG5Ykp5SOhhb3SrV7Oqb3SN3lg9lbEyGBHa/lY SUSLdMlkcEtUITRu6KcYJAVw9Pbq2O8AZWYPZSjToZxpEFv4+53VOSr3mkpFQxMc dzral/n0Yyw+XsqIke1kdzWpbCGrPAy0Pm5BGB7Fsi9iq1JbVjVi47ZIk4L16L0H gmgII1jsJy8+R3XXpGRZ =x/tu -----END PGP SIGNATURE-----

1 0

Re: [boost] [Boost-users] Boost 1.61.0 has been released
by Daniel James 18 May '16

18 May '16

On 17 May 2016 at 21:42, Raffi Enficiaud <raffi.enficiaud(a)mines-paris.org> wrote: > > Thanks! > The boost.test documentation has the banner "click here to view the latest > version on this page" on the top: > http://www.boost.org/doc/libs/1_61_0/libs/test/doc/html/index.html > > Sorry for the late mention, I thought it was because 1.61 was not released > yet. > Anything I did wrong? Anything I can do? Sorry about that, it was a bug. It should be fixed now, you might have to shift-refresh to see the fixed page.

1 0

Review Wizard Report for May 2016
by Ronald Garcia 18 May '16

18 May '16

============================================== Review Wizard Status Report for May 2016 ============================================== News ==== 1. Boost 1.58 Released April 2015. New Libraries: Endian, Sort 2. Metaparse Library Accepted 3. Hana Library Accepted 4. DLL Library Accepted 5. Http Library Rejected 6. Boost 1.59 Released August 2015. New Libraries: Coroutine2, Convert 7. AFIO Library Reviewed 8. Fiber Library Conditionally Accepted 9. Boost 1.60 Released December 2015. New Libraries: Variadic Macro Data 10. Quaternions, Vectors, Matrices Accepted 11. Fit Library Rejected 11. Boost 1.61 Released May 2016. New Libraries: Compute, DLL, Metaparse, Hana Open Issues =========== The following libraries have review managers, but have not yet been scheduled for review: * Range Extensions - added May 2012; review manager: Neil Groves. The following libraries have been reviewed and await reports from their review managers: * AFIO - reviewed August 2015; review manager: Ahmed Charles. The following libraries have been accepted to Boost, but have not yet been integrated into Boost Git: * Contract - accepted September 2012; author: Lorenzo Caminiti. * Quaternions,Vectors,Matrices - accepted December 2015; author: Emil Dotchevski The following libraries have been accepted and submitted to Boost Git, but have not yet appeared in a release: * none The following libraries have been accepted provisionally to Boost, but have not been submitted for mini-review and full acceptance: * none General Announcements ===================== As always, we need experienced review managers. Please take a look at the list of libraries in need of managers and check out their descriptions. In general review managers are active boost participants, including library contributors, infrastructure contributors, and other mailing list participants with a substantial track record of constructive participation. If you can serve as review manager for any of them, email Ron Garcia or John Phillips, "rxg at cs dot ubc dot ca" and "johnphillipsithica at gmail dot com" respectively. We are also suffering from a lack of reviewers. While we all understand time pressures and the need to complete paying work, the strength of Boost is based on the detailed and informed reviews submitted by you. If you are interested in reviewing a library but won't have time during the review period, you can always prepare your review ahead of time. No rule says you can only work on a review during the review period. A link to this report will be posted to www.boost.org. If you would like us to make any modifications or additions to this report, please email Ron or John. The review schedule is an unordered list of the libraries awaiting review. As such, any library on the schedule can be reviewed once the developer is ready, a review manager has been secured, and the manager, developer, and wizards agree on a date to schedule the review. Review Schedule =============== * Join (M) * Block Pointer (M) * Singularity (M) * Extended Complex Numbers (M) * Boost.Range Extensions * Nowide (M) * Array (M) * STL Extensions (M) * Countertree (M) * Process (M) * Application (M) * Edit Distance (M) * Mixin (M) * Dependency Injection (M) * Segmented Tree * Fiber ``(M)`` marks libraries that need review managers. -------------------- Join ---- :Author: Yigong Liu :Review Manager: Needed :Download: http://channel.sourceforge.net/ :Description: Join is an asynchronous, message based C++ concurrency library based on join calculus. It is applicable both to multi-threaded applications and to the orchestration of asynchronous, event-based applications. It follows Comega's design and implementation and builds with Boost facilities. It provides a high level concurrency API with asynchronous methods, synchronous methods, and chords which are "join-patterns" defining the synchronization, asynchrony, and concurrency. Block Pointer ------------- :Author: Phil Bouchard :Review Manager: Needed :Download: https://svn.boost.org/svn/boost/sandbox/block_ptr/ :Description: Deterministic memory manager of constant complexity capable of handling cyclic collections. Singularity ----------- :Author: Ben Robinson :Review Manager: Needed :Download: https://github.com/cppmaven/Singularity :Description: The Singularity Design Pattern allows you to restrict any class to a single instance. Unlike the infamous Singleton, Singularity gives you direct control over the lifetime of the object, does not require you to grant global access to the object, nor does it limit you to the default constructor for that object. Extended Complex Numbers ------------------------ :Author: Matthieu Schaller :Review Manager: Needed :Download: http://code.google.com/p/cpp-imaginary-numbers/ :Description: The library is an extension of the std::complex class addressing two issues: 1. The standard does not guaranty the behaviour of the complex class if instantiated with types other than float/double/long double. 2. Some calculation where pure imaginary numbers (i.e. multiples of sqrt(-1)) appear are unnecessarily slowed down due to the lack of support for these numbers. The code I submit contains two interleaved classes boost::complex and boost::imaginary which can be instantiated with any type T provided T overloads the usual arithmetic operators and some basic (real) mathematical functions depending on which complex function will be used. It is thus an extended version of Thorsten Ottosen's n1869 proposal (http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2005/n1869.html) Range Extensions ---------------- :Author: Akira Takahashi :Review Manager: Neil Groves :Download: https://github.com/faithandbrave/OvenToBoost :Description: This project adds some features of the Oven Range Library to Boost.Range. Features: - Additional Range Adaptors (taken, taken_while, dropped, dropped_while, elements, elements_key, memoized, outdirected) - Extensions for using Lambda (regular function, regular operator) - Infinite Range (iteration function) - and additional range utilities. Nowide ------ :Author: Artyom Beilis :Review Manager: Needed :Download: http://cppcms.com/files/nowide/ :Description: This library makes cross platform Unicode aware programming easier. It provides an implementation of standard C and C++ library functions, such that their inputs are UTF-8 aware on Windows without requiring to use Wide API. Array ----- :Author: Brian Smith :Review Manager: Needed :Download: https://github.com/BrianJSmith/Array :Description: The array class is a C++11 compatible implementation of static multidimensional arrays. STL Extensions -------------- :Author: Vadim Stadnik :Review Manager: Needed :Download: https://github.com/vstadnik/stl_ext_adv_review :Description: The proposed library [stl_ext_adv] offers augmented array based B+ trees and STL containers that support the interfaces of the C++03 sequences and associative containers. The library offers a number of extensions and performance improvements that are not available in C++03 and C++11 standard containers. Countertree ----------- :Author: Francisco Jose Tapia :Review Manager: Needed :Download: https://dl.dropbox.com/u/8437476/works/countertree_code_doc.zip :Description: This library is an implementation of a binary red-black counter tree. This tree have an additional counter in each leaf. This permit the access to the elements by the position, like in a vector. It is a random access container with random access iterators. COUNTERTREE This kind of trees have an additional counter in each leaf. This permit the access to the elements by the position, like in a vector. It is a random access container with random access iterators. With unordered information we have a vector with the same speed inserting and deleting in any position (O(log N)). With ordered information, we have the classes set, multiset, map and multimap, with identical interface than the STL classes, with the plus of access to the elements by position, like in a vector. The iterators are random access , and you can subtract them. SUBALLOCATOR The suballocator is a layer between the allocator and the data structures, compatible with any allocator with the STL definition. The suballocator replace to the allocator in the allocation of equal size elements. It provides speed, return the unused memory and decrease the memory used by the program and improve the cache performance due to the data locality improvement ( 30% of improvement of speed respect the std::allocator with GCC 4.7) Process ------- :Author: Boris Schaeling :Review Manager: Needed :Download: http://www.highscore.de/boost/process0.5/process.zip :Description: Boost.Process is a library to manage system processes. It can be used to: * create child processes * setup streams for child processes * communicate with child processes through streams (synchronously or asynchronously) * wait for processes to exit (synchronously or asynchronously) * terminate processes Application ----------- :Author: Renato Tegon Forti :Review Manager: Needed :Download: https://github.com/retf/Boost.Application :Documentation: http://www.dokfile.com/appbeta4/docs/libs/application/doc/html/index.html :Description: Application provides an application environment, or start point to any people that want a basic infrastructure to build an system application on Windows or Unix Variants (e.g. Linux, MacOS). Application uses behaviours modeled using 'aspects' concept proposed by 'Vicente J. Botet Escriba', that allow easy extension and customization of library components. The application modes uses these components internally to achieve the user desirable behaviours. Application provide many useful ready-to-use features, e.g: * Run application as Windows Service; * Run application as UNIX/POSIX Daemon; * Plugin extension system; * Process(executable) Single instance Instantiation support; * Application SIGNAL/Callbacks customization; * Windows Service Setup feature; * And many others. Edit Distance ------------- :Author: Erik Erlandson :Review Manager: Needed :Download: https://github.com/erikerlandson/algorithm/tree/edit_distance/sequence :Description: The edit distance is the length of the shortest (or least-cost) edit script from one sequence to another, where an edit script is defined as a sequence of insertion, deletion and (optionally) substitution operations. The function implementing the edit distance is named edit_distance. This function will return the edit distance between two sequences, where sequences may be any valid range object supporting forward iteration. The edit_distance function will also, if requested, return the edit script. Mixin ----- :Author: Borislav Stanimirov :Download: https://github.com/iboB/boost.mixin :Documentation: http://ibob.github.io/boost.mixin/ :Review Manager: Needed :Description: Boost.Mixin is a library that allows the composition and modifications of polymorphic types at run time. Types and objects are constructed out of building blocks called mixins. The library uses the type boost::mixin::object as a placeholder, whose instances can be extended with existing classes (mixins), thus providing a particular instance with the functionality of all those types. Accessing the newly formed type's interface is made through messages: stand-alone functions generated by the library, which can be thought of as methods. This is given while also having full abstraction between the interface and the definition of types. An existing feature in another language similar to Boost.Mixin and also an inspiration for the library are the mixins in Ruby. The library also has similarities with the pattern entity-component-system. Dependency Injection -------------------- :Author: :Download: https://github.com/krzysztof-jusiak/di :Documentation: http://krzysztof-jusiak.github.io/di/boost/libs/di/doc/html :Incubator: http://rrsd.com/blincubator.com/bi_library/di-dependency-injection/?gform_p… :Review Manager: Needed :Description: Boost.DI is a dependency injection library improving manual dependency injection by simplifying object instantiation with automatic dependencies injection. Using Boost.DI has many advantages over manual dependency injection. * Reduce boilerplate code (No factories, no objects creation in specific order) * Reduce cost of maintenance effort (Constructor signature change won't affect di configuration) * Reduce testing effort * Give better control of what and how is created (Policies, Providers) * Give better understanding about objects hierarchy (UML Dumper) Segmented Tree -------------- :Author: Chris Clearwater :Download: http://rrsd.com/blincubator.com/bi_library/segmentedtreeseq-2/?gform_post_i… :Repository: http://github.com/det/segmented_tree :Documentation: https://det.github.io/segmented_tree :Review Manager: Glen Fernandes :Description: SegmentedTreeSeq is a sequence data structure like vector and deque that supports efficient random access insert and erase. It is implemented using B+Trees and has an emphasis on speed and a low memory overhead. Fiber ----- :Author: Oliver Kowalke :Download: https://github.com/olk/boost-fiber :Documentation: http://olk.github.io/libs/fiber/doc/html/ :Review Manager: Nat Goodspeed :Description: Boost.Fit is a header-only C++11/C++14 library that provides utilities for functions and function objects. Libraries under development =========================== See The Boost Library Incubator Project at http://blincubator.com for discussion of libraries currently under development.

2 1

Re: [boost] [proto][variant] variant crashes proto expression
by Igor R. 17 May '16

17 May '16

> // The values bound to the placeholders > Value *d[2]; <...> > // The result of evaluating arithmetic expressions > typedef Value& result_type; So, you store pointers to the variants and return references, thus preventing copying. But why does the copying cause the aforementioned crash? Does it look like a bug in Proto? That's quite weird, because I never encountered any issue with variant copying... -- View this message in context: http://boost.2283326.n4.nabble.com/proto-variant-variant-crashes-proto-expr… Sent from the Boost - Dev mailing list archive at Nabble.com.

1 0

Boost Build and Test
by Robert Ramey 17 May '16

17 May '16

I started a new thread to accommodate the widening discussion on CMake. Build and Test systems: I've always been a big complainer about Boost Build. Now I'm a big complainer about CMake as well. Just so you know. I always found it weird that the buiding of libraries jam file was stashed in it's own directory - build while jam files for other components like test and building docs was found inside their respective directories. I also added to the serialization library some other jam files in subdirectories example and in performance. So to me by far the most natural place to find the library jam file would be in the directory we've agreed to name src. I never made any issue of this as my whole progress through life is about moving on to get my own projects done. Largely motivated by the desire to do cutting edge C++ development I replaced my old windows system with a mac mini. Soon I wanted to build and test my projects in XCode IDE. I like to use an IDE, but setting it and maintaining it for a project like the serialization library is an incredible amount of work. So I resolved to setup CMake to do the job. I had exposure to CMake before and found it no better than all the other build systems. But it needed to do what I wanted it to do - create the IDE project and it was very popular. So I managed to make it work in this context and the result has been quite satisfactory. But making it run all the tests I want to run - different compilers, libraries, etc. etc. integrating with my own library_status dashboard builder looked like a serious pain and I already had an elaborate Jamfile set for doing all of that. So upshot is I use them both for different purposes. I don't see anything wrong with that. In order not to upset the established structure I put my CMakeLists.txt file inside it's own directory. If it was totally up to me, what I'd like to see is: a) jam files in the build directory moved to src b) thereby acknowledging the practice of having jam files in the same directories which contain the build sources. c) which is pretty much the same as the CMake approach. c) official tolerance for including other build systems at the same level such as CMakeLists.txt and maybe MS projects and solutions. d) official tolerence for including a top level CMakeLists.txt. Personally I don't think this is necessary or even a good idea - but I want to leave that as a separate discussion. Robert Ramey

1 0

Final benchmark graphs for Colony vs std:: containers now available
by Soul Studios 17 May '16

17 May '16

Re-wrote my benchmark code from scratch a month or two ago with some help from Baptiste Wiche, have run over std::list, std::map, std::multiset, std::deque, std::vector, and for GCC, Chris's segmented_tree implementation. To be honest there's not much point comparing against segmented_tree, as the goals are totally different (efficient random access insertion for segtree, vs efficient unordered erasure/insertion/iteration without pointer invalidation colony), but there was some interest last time I wrote here. In addition I compared against other methods for ensuring pointer/index validity using deques and vectors, to see how those things pan out. Graphs are available here: http://www.plflib.org/colony.htm#benchmarks and here: http://www.plflib.org/stack.htm There are also MSVC 2013 results linked to in the first paragraph of the benchmarks. Comments are welcome, but please read the page first. Stack performs particularly well, outperforming all alternatives in both GCC/MSVC.

3 16

Boost ICL tests attempting to pass non-bidirectional iterator to std::reverse_copy
by Billy O'Neal (VC LIBS) 16 May '16

16 May '16

Hi folks. I'm not a Boost.ICL expert, but we detected this one failure with our in-development STL and this test case: template <ICL_IntervalSet_TEMPLATE(_T) IntervalSet, class T> void interval_set_element_iter_4_discrete_types() { typedef IntervalSet<T> IntervalSetT; typedef typename IntervalSetT::interval_type IntervalT; typedef std::vector<T> VectorT; IntervalSetT set_a; set_a.add(I_I(1,3)).add(I_I(6,7)); VectorT vec(5), cev(5); vec[0]=MK_v(1);vec[1]=MK_v(2);vec[2]=MK_v(3);vec[3]=MK_v(6);vec[4]=MK_v(7); cev[0]=MK_v(7);cev[1]=MK_v(6);cev[2]=MK_v(3);cev[3]=MK_v(2);cev[4]=MK_v(1); VectorT dest; std::copy(elements_begin(set_a), elements_end(set_a), std::back_inserter(dest)); BOOST_CHECK_EQUAL( vec == dest, true ); dest.clear(); std::copy(elements_rbegin(set_a), elements_rend(set_a), std::back_inserter(dest)); BOOST_CHECK_EQUAL( cev == dest, true ); dest.clear(); std::reverse_copy(elements_begin(set_a), elements_end(set_a), std::back_inserter(dest)); BOOST_CHECK_EQUAL( cev == dest, true ); dest.clear(); std::reverse_copy(elements_rbegin(set_a), elements_rend(set_a), std::back_inserter(dest)); BOOST_CHECK_EQUAL( vec == dest, true ); } which produces this failure: C:\Dev\WCFB01_01\binaries\x86ret\inc\algorithm(1672): error C2665: 'std::_Reverse_copy1': none of the 2 overloads could convert all the argument types C:\Dev\WCFB01_01\binaries\x86ret\inc\algorithm(1655): note: could be '_OutIt std::_Reverse_copy1<_Iter,_OutIt>(_BidIt,_BidIt,_OutIt,std::random_access_iterator_tag,std::random_access_iterator_tag)' with [ _OutIt=std::back_insert_iterator<VectorT>, _Iter=boost::icl::element_iterator<std::_Tree_const_iterator<std::_Tree_val<std::_Tree_simple_types<boost::icl::discrete_interval<bicremental_type_5,std::less>>>>>, _BidIt=boost::icl::element_iterator<std::_Tree_const_iterator<std::_Tree_val<std::_Tree_simple_types<boost::icl::discrete_interval<bicremental_type_5,std::less>>>>> ] C:\Dev\WCFB01_01\binaries\x86ret\inc\algorithm(1645): note: or '_OutIt std::_Reverse_copy1<_Iter,_OutIt>(_BidIt,_BidIt,_OutIt,std::bidirectional_iterator_tag,std::_Any_tag)' with [ _OutIt=std::back_insert_iterator<VectorT>, _Iter=boost::icl::element_iterator<std::_Tree_const_iterator<std::_Tree_val<std::_Tree_simple_types<boost::icl::discrete_interval<bicremental_type_5,std::less>>>>>, _BidIt=boost::icl::element_iterator<std::_Tree_const_iterator<std::_Tree_val<std::_Tree_simple_types<boost::icl::discrete_interval<bicremental_type_5,std::less>>>>> ] C:\Dev\WCFB01_01\binaries\x86ret\inc\algorithm(1672): note: while trying to match the argument list '(boost::icl::element_iterator<std::_Tree_const_iterator<std::_Tree_val<std::_Tree_simple_types<boost::icl::discrete_interval<DomainT,Compare>>>>>, boost::icl::element_iterator<std::_Tree_const_iterator<std::_Tree_val<std::_Tree_simple_types<boost::icl::discrete_interval<DomainT,Compare>>>>>, std::back_insert_iterator<VectorT>, boost::iterators::detail::iterator_category_with_traversal<std::input_iterator_tag,Traversal>, std::output_iterator_tag)' with [ DomainT=bicremental_type_5, Compare=std::less ] and [ DomainT=bicremental_type_5, Compare=std::less ] and [ Traversal=boost::iterators::bidirectional_traversal_tag ] c:\dev\wcfb01_01\src\qa\vc\fe\3rdpartycomp\boost_1_60_0\libs\icl\test\fastest_interval_set_\../test_interval_set_shared.hpp(810): note: see reference to function template instantiation '_OutIt std::reverse_copy<boost::icl::element_iterator<std::_Tree_const_iterator<std::_Tree_val<std::_Tree_simple_types<boost::icl::discrete_interval<DomainT,Compare>>>>>,std::back_insert_iterator<VectorT>>(_BidIt,_BidIt,_OutIt)' being compiled with [ _OutIt=std::back_insert_iterator<VectorT>, DomainT=bicremental_type_5, Compare=std::less, _BidIt=boost::icl::element_iterator<std::_Tree_const_iterator<std::_Tree_val<std::_Tree_simple_types<boost::icl::discrete_interval<bicremental_type_5,std::less>>>>> ] c:\dev\wcfb01_01\src\qa\vc\fe\3rdpartycomp\boost_1_60_0\libs\icl\test\fastest_interval_set_\../fastest_interval_set_cases.hpp(61): note: see reference to function template instantiation 'void interval_set_element_iter_4_discrete_types<boost::icl::interval_set,discrete_type_2>(void)' being compiled We are considering reverting this enforcement of iterator category tag in our STL, but technically a standard library appears within its rights to reject this. Billy Robert O'Neal III SDE II - Visual C++ Libraries bion(a)microsoft.com

1 0

media file errors
by Rainer Deyke 15 May '16

15 May '16

"CDs/Reverend Bizarre - III - So Long Suckers (disc 1)" is redundant and should be deleted. In "CDs/Shadow Gallery - Room V": "Shadow Gallery - Seven Seas.mp3" -> "Shadow Gallery - Seven Years.mp3" -- Rainer Deyke (rainerd(a)eldwood.com)

1 0

Call for Submissions: International Conference on Information Society (i-Society 2016), Technical Co-Sponsored by IEEE UK/RI Chapter!
by Faye Bewsy 13 May '16

13 May '16

1 0

[proto][variant] variant crashes proto expression
by Igor R 13 May '16

13 May '16

The following code is a slightly modified Proto calc2 example. Instead of doubles I use variant<int, double>, and the expression is just _1 = _2. This code triggers assertion in variant/detail/forced_return.hpp, so it looks like some variant instance gets messed up. It happens when the value returned from proto::eval(*this, ctx) is being copied. It can be reproduced both with MSVC and gcc, with Boost 1.60. Is there any workaround for this issue? Thanks. ////////////// #include <iostream> #include <boost/proto/proto_typeof.hpp> #include <boost/proto/core.hpp> #include <boost/proto/context.hpp> #include <boost/variant.hpp> namespace proto = boost::proto; using proto::_; typedef boost::variant<int, double> var_t; template<typename Expr> struct calculator_expression; // Tell proto how to generate expressions in the calculator_domain struct calculator_domain : proto::domain<proto::generator<calculator_expression> > {}; // Will be used to define the placeholders _1 and _2 template<int I> struct placeholder {}; // Define a calculator context, for evaluating arithmetic expressions // (This is as before, in calc1.cpp) struct calculator_context : proto::callable_context< calculator_context const > { // The values bound to the placeholders var_t d[2]; // The result of evaluating arithmetic expressions typedef var_t result_type; explicit calculator_context(const var_t &d1 = var_t(), const var_t &d2 = var_t()) { d[0] = d1; d[1] = d2; } // Handle the evaluation of the placeholder terminals template<int I> result_type operator ()(proto::tag::terminal, placeholder) const { return d[ I - 1 ]; } }; // Wrap all calculator expressions in this type, which defines // operator () to evaluate the expression. template<typename Expr> struct calculator_expression : proto::extends<Expr, calculator_expression<Expr>, calculator_domain> { explicit calculator_expression(Expr const &expr = Expr()) : calculator_expression::proto_extends(expr) {} BOOST_PROTO_EXTENDS_USING_ASSIGN(calculator_expression<Expr>) // Override operator () to evaluate the expression var_t operator ()() const { calculator_context const ctx; return proto::eval(*this, ctx); } var_t operator ()(const var_t &d1) const { calculator_context const ctx(d1); return proto::eval(*this, ctx); } var_t operator ()(const var_t &d1, const var_t &d2) const { calculator_context const ctx(d1, d2); return proto::eval(*this, ctx); } }; // Define some placeholders (notice they're wrapped in calculator_expression<>) calculator_expression<proto::terminal< placeholder< 1 > >::type> const _1; calculator_expression<proto::terminal< placeholder< 2 > >::type> const _2; // Now, our arithmetic expressions are immediately executable function objects: int main() { BOOST_PROTO_AUTO(expr, _1 = _2); var_t a1(1), a2(2.5); expr(a1, a2); return 0; }

3 2

[intrusive] crash with slist push_back
by Arpan Sen 12 May '16

12 May '16

Hi Boost Dev, Please consider the following code, this crashes with slist but works just fine if I replace slist with list. Also flat_map crashes but std::map works fine. Am I doing something gross or is there a bug here? #include <iostream> #include <boost/container/flat_map.hpp> #include <map> //#include <boost/intrusive/list.hpp> #include <boost/intrusive/slist.hpp> using namespace boost::intrusive; struct m : public slist_base_hook<> { int n; public: m(int k) : n(k) { } }; int main() { boost::container::flat_map<int, slist<m, cache_last<true> > > c1; std::map<int, slist<m, cache_last<true> > > c2; m* m1 = new m(22); c1[1].push_back(*m1); m* tt = new m(99); c2[1].push_back(*tt); } Regards Arpan

2 1

Using thread_local with Boost.Thread
by Ruediger Berlich 11 May '16

11 May '16

Hi there, I am curious whether it would be possible to use C++11 thread_local instead of Boost's own TLS, while continuing to use Boost.Thread ? I assume that there will be problems if Boost falls back to native pthread ? Kind Regards, Beet

1 0

Boost 1.61.0 Release Candidate 2
by Vladimir Prus 11 May '16

11 May '16

The second release candidates for the 1.61.0 release are now available at: http://boost.cowic.de/rc/boost_1_61_0_rc2.zip http://boost.cowic.de/rc/boost_1_61_0_rc2.7z http://boost.cowic.de/rc/boost_1_61_0_rc2.tar.bz2 http://boost.cowic.de/rc/boost_1_61_0_rc2.tar.gz The SHA256 checksums are as follows: fa1c34862b7ba8674ed6e064a14667a11830c6252f702d9458451834b74f7815 boost_1_61_0_rc2.7z a547bd06c2fd9a71ba1d169d9cf0339da7ebf4753849a8f7d6fdb8feee99b640 boost_1_61_0_rc2.tar.bz2 a77c7cc660ec02704c6884fbb20c552d52d60a18f26573c9cee0788bf00ed7e6 boost_1_61_0_rc2.tar.gz 02d420e6908016d4ac74dfc712eec7d9616a7fc0da78b0a1b5b937536b2e01e8 boost_1_61_0_rc2.zip The changes relative to RC1 are MSVC fixes for signals2 and graph libraries. As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. The signed list of checksums is also attached, signed with the following key: https://pgp.mit.edu/pks/lookup?op=get&search=0xDA472E8659753BA4 Key fingerprint C5F0 F367 AA66 616F B839 806E DA47 2E86 5975 3BA4 Thanks! -- The release managers

9 14

[lockfree] _ENABLE_ATOMIC_ALIGNMENT_FIX for VS 2015 Update 2
by Stephan T. Lavavej 11 May '16

11 May '16

Hi, While running Boost.Lockfree's tests, one of our compiler devs encountered the following failure: freelist_test.cpp c:\wcfb01\binaries\x86chk\inc\atomic(659): error C2338: You've instantiated std::atomic<T> with sizeof(T) equal to 2/4/8 and alignof(T) < sizeof(T). Before VS 2015 Update 2, this would have misbehaved at runtime. VS 2015 Update 2 was fixed to handle this correctly, but the fix inherently changes layout and breaks binary compatibility. Please define _ENABLE_ATOMIC_ALIGNMENT_FIX to acknowledge that you understand this, and that everything you're linking has been compiled with VS 2015 Update 2 (or later). c:\wcfb01\binaries\x86chk\inc\atomic(669): note: see reference to class template instantiation 'std::_Atomic_base<_Ty,4>' being compiled with [ _Ty=boost::lockfree::detail::tagged_index ] e:\boost\boost\boost\lockfree\detail\freelist.hpp(608): note: see reference to class template instantiation 'std::atomic<boost::lockfree::detail::tagged_index>' being compiled e:\boost\boost\boost\lockfree\detail\freelist.hpp(609): note: see reference to class template instantiation 'boost::lockfree::detail::fixed_size_freelist<T,NodeStorage>' being compiled call "C:\WCFB01\binaries\x86chk\bin\i386\vcvarsall.bat" x86 >nul cl /Zm800 -nologo @"..\bin.v2\libs\lockfree\test\freelist_test.test\msvc-latest\debug\threading-multi\freelist_test.obj.rsp" ...failed compile-c-c++ ..\bin.v2\libs\lockfree\test\freelist_test.test\msvc-latest\debug\threading-multi\freelist_test.obj... with the following type: class tagged_index { public: typedef boost::uint16_t tag_t; typedef boost::uint16_t index_t; protected: index_t index; tag_t tag; }; This is by design - your tagged_index has align 2, size 4, triggering the need for my atomic alignment fix. As the static_assert advises, your code needs to define _ENABLE_ATOMIC_ALIGNMENT_FIX in order to pass. If this has already been fixed in 1.61.0, then that's great (I haven't checked). Thanks, STL

5 14

Getting started with boost in Codeblocks
by Karan Kapoor 11 May '16

11 May '16

Hi, This is Karan Kapoor,a 3rd year UG student at NSIT. Can somebody guide me how to get started with boost libraries while i am using codeblocks. Karan Kapoor

2 1

Boost.Random subtract_with_carry doesn't like m == numeric_limits<result_type>::digits
by Billy O'Neal (VC LIBS) 10 May '16

10 May '16

Hello, Boost folks. I found a bug in subtract_with_carry_engine while fixing a bug in MSVC++'s implementation of the same, where m == numeric_limits<result_type>::digits. Consider the following: #include <stdlib.h> #include <stdio.h> #ifdef USE_BOOST #include <boost/random/subtract_with_carry.hpp> using namespace boost::random; #else #include <random> using namespace std; #endif template <typename Engine> typename Engine::result_type run_10k(Engine engine) { for (int i = 0; i < 9999; ++i) { engine(); } return engine(); } int main() { subtract_with_carry_engine<unsigned long long, 64, 10, 24> ull_swc; ull_swc.seed(0x12341234'00000000); printf("0x%016llX\n", run_10k(ull_swc)); } MSVC++ said: 0xFCF0A4776BA0A6A8 Libstdc++ says: 0x01316AEA3646F686 Libc++ says: 0x01316AEA3646F686 Boost 1.60.0/libc++ + Clang says: 0x69E18848FE1BD36D Boost 1.60.0/libstdc++ + g++ says: 0x1DD6C263C41EEED0 MSVC++'s bug was that we did the underflow check incorrectly resulting in the carry bit always being set if m == numeric_limits<result_type>::digits. I fixed that and MSVC++ will agree with libstdc++ and libc++ in the next update; but boost's behavior here is still strange. Hope that helps, Billy Robert O'Neal III SDE II - Visual C++ Libraries bion(a)microsoft.com

2 1

[thread] API for getting/setting thread name in Boost?
by Bob Summerwill 10 May '16

10 May '16

I've also been working with an external developer which is getting Ethereum C++ working on Alpine Linux, as a statically linked executable using musl, rather than glibc. One rather confusing element was related to setting and getting thread names, which is the process of working through this issue, I find appears not to have made its way into either Boost or the C++11 standard library, though it must be a very common cross-platform use-case. https://github.com/ethereum/libweb3core/pull/73 https://github.com/ethereum/libweb3core/pull/73/files I've just added this comment-block, while fixing the issue: /// Set the current thread's log name. /// /// It appears that there is not currently any cross-platform way of setting /// thread names either in Boost or in the C++11 runtime libraries. What is /// more, the API for 'pthread_setname_np' is not even consistent across /// platforms which implement it. /// /// A proposal to add such functionality on the Boost mailing list, which /// I assume never happened, but which I should follow-up and ask about. /// http://boost.2283326.n4.nabble.com/Adding-an-option-to-set-the-name-of-a-bo… /// /// man page for 'pthread_setname_np', including this crucial snippet of /// information ... "These functions are nonstandard GNU extensions." /// http://man7.org/linux/man-pages/man3/pthread_setname_np.3.html /// /// Stack Overflow "Can I set the name of a thread in pthreads / linux?" /// which includes useful information on the minor API differences between /// Linux, BSD and OS X. /// http://stackoverflow.com/questions/2369738/can-i-set-the-name-of-a-thread-i… /// /// musl mailng list posting "pthread set name on MIPs" which includes the /// information that musl doesn't currently implement 'pthread_setname_np' /// https://marc.info/?l=musl&m=146171729013062&w=1 void setThreadName(std::string const& _n); Would I be right in assuming that this never happened? http://boost.2283326.n4.nabble.com/Adding-an-option-to-set-the-name-of-a-bo… If not, where can I log an issue to request that we revisit that? From what I can see, everybody is likely just cut-and-pasting much the same code for this functionality. http://stackoverflow.com/questions/10121560/stdthread-naming-your-thread Cheers, Bob Summerwill -- bob(a)summerwill.net

2 7

[config] Boost and the Intel (Linux) compiler
by Bob Summerwill 10 May '16

10 May '16

I am a developer on the Ethereum C++ client ( https://github.com/ethereum/webthree-umbrella) and have been working with an external developer on adding support to the codebase for building with the Intel Compiler on Ubuntu. Here is the full log of pain :-) https://github.com/ethereum/webthree-umbrella/issues/396 We've already merged various changes, and we appear to be getting down to the real hard ones, which are now mainly clustered around build issues with boost::multiprecision and seeming limitations with the Intel compiler and Like so: /home/libweb3core/libdevcore/Base64.h(48): error: no suitable conversion function from "boost::multiprecision::number<boost::multiprecision::backends::cpp_int_backend<160U, 160U, boost::multiprecision::unsigned_magnitude, boost::multiprecision::unchecked, void>, boost::multiprecision::et_off>" to "unsigned int" exists unsigned r = (unsigned)(a - a / 36 * 36); // boost's % is broken ^ detected during instantiation of "std::string dev::toBase36(const dev::FixedHash<N> &) [with N=20UL]" at line 114 of "/home/libethereum/libethcore/ICAP.cpp" This appears to be the key observation: https://github.com/ethereum/webthree-umbrella/issues/396#issuecomment-20659… "In summary, the intel platform supports this "convert_to" member function, but does not support implicit conversion of boost multiprecision types" Has anybody worked with Boost and the Intel compiler who might have some further insight into whether there is some way in which the Intel compiler "warts" can be handed within Boost? Or are we stuck with these nasty diffs/workarounds? https://github.com/ethereum/libethereum/pull/224/files https://github.com/ethereum/libweb3core/pull/68/files Cheers, Bob Summerwill Developer, Ethereum Foundation -- bob(a)summerwill.net

3 4

github issues tracking listing
by Vicente J. Botet Escriba 09 May '16

09 May '16

Hi, I would like to have the possibility to have github issues in my boost modules (thread/chrono/ratio). I see that Boost.Hana has its own issue list. What I need to do to add the possibility to add issues? Best, Vicente

3 3

Boost 1.61.0 Release Candidate 1
by Vladimir Prus 09 May '16

09 May '16

The release candidates for the 1.61.0 release are now available at: http://boost.cowic.de/rc/boost_1_61_0_rc1.zip http://boost.cowic.de/rc/boost_1_61_0_rc1.7z http://boost.cowic.de/rc/boost_1_61_0_rc1.tar.bz2 http://boost.cowic.de/rc/boost_1_61_0_rc1.tar.gz The SHA256 checksums are as follows: dcd11a91a412b2e8a78678b38cb2a74857e61f9bfe2577de9fd70be770100d54 boost_1_61_0_rc1.7z 476937369c7a82103b734ccae85d35a523cdb7f8462c5f2fe1217ff0c8e2a7df boost_1_61_0_rc1.tar.bz2 e60dee39ebb29d24bf8a4ef9aec34dbb8c1b9b219d4737ea4b358f38b1aab2b7 boost_1_61_0_rc1.tar.gz e5f662f44a65c5c19450b8a1c07f75c7d5f16e58667871e856ba3984ec082006 boost_1_61_0_rc1.zip As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. The signed list of checksums is also attached, signed with the following key: https://pgp.mit.edu/pks/lookup?op=get&search=0xDA472E8659753BA4 Key fingerprint C5F0 F367 AA66 616F B839 806E DA47 2E86 5975 3BA4 Thanks! -- The release managers

14 38

[Style] Import a C function with wrong signature on purpose
by Klemens Morgenstern 08 May '16

08 May '16

Hi, for the boost.process library I need WinAPI functions which take an enumerator. Problem is: the forward-declaration doesn't work here, even with C++11. I.e. this code is still illegal, because X has a non-fixed type: enum X {}; enum X : typename std::underlying_type<X>::type ; I do however know which values the enum has take, thus I can redeclare it and have the reasonable expectation, that it will use the same underlying type. So theoretically, I could import the function into a seperate namespace (using extern "C") and use it, while having it declared with another enum type. I.e. you have in some C code the declaration: enum X { a,b,c}; void f(X); And I'll write in my code without including the other header: namespace import_thingy { extern "C" { enum X { a,b,c}; void f(X); } To be absolutely sure, I'd add an test, which asserts that the underlying types are equal. Now of course, that would never be accepted into the boost/winapi module, but I could just add this in my library. Would this be a dealbreaker for a library attempting to become a boost-library? If so, I'd need to put it into a source file and include windows.h there, but I'd really like the library to be header-only and under no circumstances include windows.h there. Thanks, Klemens

2 6

What to do about std::binary_function and std::unary_function?
by Nick Matteo 07 May '16

07 May '16

std::binary_function and std::unary_function are deprecated, and scheduled to be removed from the standard in C++17. That means it's possible that code using these might soon fail to compile when targeting this standard. These are still used throughout Boost, including by the libraries Accumulators, Algorithm, Bimap, Function, Functional, GIL, Graph, ICL, MPI, Polygon, and Xpressive. You can see all the uses I found in the 1.61 beta boost/ directory at http://kundor.github.io/ubinary_function_list.html . All that these classes do are provide the typedefs result_type, and argument_type (for unary_function) or first_argument_type and second_argument_type (for binary_function). In particular, they do not include a virtual operator(), so that one cannot accept a function object polymorphically as a std::binary_function&, for example. So, although it is conceivable that C++98-era user code might check for inheritance from std::binary_function, it seems rather unlikely: practically all uses should just depend on the typedefs being present (which is what the standard library has always done). With modern C++ standards, the availability of std::result_of, decltype, and std::function make these typedefs redundant, and references to them are being phased out of the standard library (starting with deprecation.) It seems to me that there are four main possibilities for removing these classes from Boost. (I'll talk about binary_function in the following, but it all applies equally to unary_function.) 1) Add some sort of compatibility macro to Boost.Config, to enable classes to inherit from std::binary_function if it is available, or add the appropriate typedefs if it is not. I don't think this is necessary. 2) Remove the inheritance from std::binary_function, and add the typedefs. This seems to be the default approach: it is used by the C++11 standard itself, and has also already been done by some Boost libraries, e.g. in container/string.hpp and in intrusive/priority_compare.hpp. The drawback here is increased verbosity. Instead of writing template <class T> struct functor : std::binary_function<T, T, bool> {...}; We must write template <class T> struct functor { typedef T first_argument_type; typedef T second_argument_type; typedef bool result_type; ... }; 3) A modification of approach 2: instead of manually adding the typedefs everywhere, make a base class to provide the typedefs somewhere in Boost. Then replace inheritance from std::binary_function<Arg1, Arg2, Result> with inheritance from boost::binary_function<Arg1, Arg2, Result>. 4) Just remove inheritance from std::binary_function (and don't provide typedefs.) This is the bold approach. The typedefs are redundant now: I think the only use in the standard library is by the deprecated std::not1/std:not2 and the deprecated binders std::bind1st/std::bind2nd (which are to be removed in C++17). This is the direction that the standard library is starting to head, with all uses of the typedefs deprecated and probably eventually removed, and even the provision of the typedefs optional in C++17 standard library function objects. This has already been done at least by Boost Interprocess in detail/mpl.hpp. Probably the best options are either (2) or (4). Should there be a default policy on what authors should do? Nick Matteo

5 6

Regression testing Clang/LLVM with VC14.
by degski 07 May '16

07 May '16

I have started a new thread as the other one "Testing of clang emualting the VC++ preprocessor on Windows" has become rather long and interlaced with less relevant musings. Here I would like to concentrate on the subject in the title. Sergey suggested I'd run regression tests, in the "other thread". I was hesitant at first, mostly due to the luke warm reception. Thanks to Google's simple coding of their spam filter, I actually missed the post by Niall Douglas of 4th of April. When it was referenced later and after I dug it from the archives, I became encouraged by the fact that maybe I wasn't all wrong and somebody within the community was actually thinking along similar lines as me. Following this I'd decided to take on regression testing. I chose to first simply test boost-develop against VC14, just to see how it goes. Some good, some bad. Was easy to set up (git already included with VC14, all what I needed to do was install python, which I normally have, but I'm having a new laptop). The bad, space required 44GB (advertised as 5GB). Possibly .pdb files (debugger symbols) are filling up disk-space uselessly. Next bad, the process finished with the following lines: # Done writing "C:\boost_develop\results\degski.xml". # Compressing "C:\boost_develop\results\degski.xml"... # Done writing "C:\boost_develop\results\degski.zip". # Uploading log archive "C:\boost_develop\results\degski.zip" to develop # <lambda> failed with message "[Errno 10013] An attempt was made to access a socket in a way forbidden by its access permissions" # Retrying (5 more attempts). # Uploading log archive "C:\boost_develop\results\degski.zip" to develop # <lambda> failed with message "[Errno 10013] An attempt was made to access a socket in a way forbidden by its access permissions" # Retrying (4 more attempts). # Uploading log archive "C:\boost_develop\results\degski.zip" to develop # <lambda> failed with message "[Errno 10013] An attempt was made to access a socket in a way forbidden by its access permissions" # Retrying (3 more attempts). # Uploading log archive "C:\boost_develop\results\degski.zip" to develop # <lambda> failed with message "[Errno 10013] An attempt was made to access a socket in a way forbidden by its access permissions" # Retrying (2 more attempts). # Uploading log archive "C:\boost_develop\results\degski.zip" to develop # <lambda> failed with message "[Errno 10013] An attempt was made to access a socket in a way forbidden by its access permissions" # Retrying (1 more attempts). # Uploading log archive "C:\boost_develop\results\degski.zip" to develop # <lambda> failed with message "[Errno 10013] An attempt was made to access a socket in a way forbidden by its access permissions" # Giving up. Traceback (most recent call last): File "run.py", line 71, in <module> runner(root) File "C:\boost_develop\boost_regression_src\regression.py", line 287, in __init__ self.main() File "C:\boost_develop\boost_regression_src\regression.py", line 624, in main getattr(self,action_m)() File "C:\boost_develop\boost_regression_src\regression.py", line 591, in command_regression self.command_upload_logs() File "C:\boost_develop\boost_regression_src\regression.py", line 538, in command_upload_logs lambda: File "C:\boost_develop\boost_regression_src\regression.py", line 663, in retry return f() File "C:\boost_develop\boost_regression_src\regression.py", line 546, in <lambda> self.dart_server ) File "C:\boost_develop\boost_regression_src\collect_and_upload_logs.py", line 430, in upload_logs upload_to_ftp( tag, logs_archive, ftp_proxy, debug_level, ftp_url ) File "C:\boost_develop\boost_regression_src\collect_and_upload_logs.py", line 256, in upload_to_ftp ftp = ftplib.FTP( ftp_site ) File "C:\Python27\lib\ftplib.py", line 120, in __init__ self.connect(host) File "C:\Python27\lib\ftplib.py", line 135, in connect self.sock = socket.create_connection((self.host, self.port), self.timeout) File "C:\Python27\lib\socket.py", line 575, in create_connection raise err socket.error: [Errno 10013] An attempt was made to access a socket in a way forbidden by its access permissions I've re-checked this page <http://www.boost.org/development/running_regression_tests.html>again, there's no mention of "registering" or something similar. Some tests must have failed, got prompted for starting the debugger twice (is the latter normal). This was a test-run (testing the testing), with VC14U2. Assuming the above can get sorted, I would in reality like to test Clang/LLVM (with VC14U2). I would like to ask (Niall Douglas in particular, I guess) what the suggested parameters to run.py should be for this combo. Should I target clang.exe or clang-cl.exe, develop or master. What about Clang/C2? How to reduce disk-space usage? degski

5 7

proposed new library "histogram"
by Hans Dembinski 06 May '16

06 May '16

Hi everybody, I recently added a new library called "histogram" to the Boost Incubator. I would like to advertise it a little here in the hope to find a person interested in reviewing it. I hope that shameless self-advertisement is not going against some rule of this list, but I am sure you will let me know. My background is in analysis of big data in the fields of particle physics and astroparticle physics. Boost is very popular among my peers, since it is a free, high-quality, rich, and very well maintained collection of libraries. There is a growing number of tools to do statistical analysis in Boost and I think this project would fit in nicely, and fill a gap. We work with histograms a lot, so that's why my interest came from. I am a senior programmer in C++ and Python with 10 years of experience. Guiding development through code reviews and tickets, as well as taking on responsibility for continuous maintenance, are natural for me. Naturally, I am willing to commit free time to maintain the project should it be accepted, and do my share of the work in this community. I put a lot of thought and effort into this project, the rationale and my design choices are explained in the documentation, which I wrote according to the advice given at the Boost Incubator website. The project is feature complete from my side. What it needs now is the input from the Boost community to round off possible edges and to make the interface rich enough for everybody. I am good at considering the user perspective, but I cannot anticipate everyone's needs. In case you got interested, here are the links: Incubator link: http://rrsd.com/blincubator.com/bi_library/histogram-2/?gform_post_id=1582 github link: https://github.com/HDembinski/histogram Best regards, Hans

6 15

1.61 release notes
by John Maddock 06 May '16

06 May '16

Is it too late to add release notes? Forgetfully yours, John.

2 1

Boost.Proto: specializing context::eval classes
by Brook Milligan 06 May '16

06 May '16

I am trying to use Boost.Proto with some user-defined function terminals. Following the documentation, this requires specialization of context::eval classes to handle new terminals. (Using the callable_context<> mechanism is too simplistic because that seems to require a uniform result_type.) However, doing as suggested (see the "Defining an Evaluation Context" section) does not compile when function terminals are involved. My solution is a new traits class that deduces the type of a terminal. This does allow successful specialization of context::eval on the type of terminal, even with functions. To illustrate this, I have attached a set of three files, one implementing an example proto function, one implementing the relevant metafunction, and one demonstrating both use cases: the one corresponding to the Boost.Proto documentation and the one corresponding to my alternative. I would appreciate comments on the following: - Is this a valid problem and a valid solution or have I missed a standard method using Boost.Proto that works to solve this pattern? - Is this the standard way of creating function terminals in Boost.Proto or have I done something there to trigger the problem? - If the answer to these questions indicates a missing feature within Boost.Proto, what is the process for fixing that? Thanks for any help you can offer. Cheers, Brook

1 0

[random] Using random_device needs to link to built library
by Edward Diener 06 May '16

06 May '16

Evidently if I use boost::random::random_device class in code I need to link to the built random library. Otherwise the random library is header only. Shouldn't this be mentioned somewhere in the Boost random documentation ?

1 0

[generic programming] header file for general "default" operations for C++ classes
by Walt Karas 05 May '16

05 May '16

In C++, a default assignment operator is generated for a class if all of its components (data members and base classes) have an assignment operator. There are plans in C++17 to do something similar for comparison operators. This header, in https://github.com/wkaras/C-plus-plus-library-default-operators , facilitates that, more generally, if there is an operation on all the components of a class, a single macro invocation can provide this operation on the class as well. A big drawback is that it's very intrusive into the class definition. Each class component must be defined using a macro, COMPOSITE_OP_MBR_T(int) i; for examle. The class will in truth be a template, with the template parameter being defaulted for normal usage. I don't know which, if any, existing Boot library this header would belong in.

3 4

[Promotional] ghournal - a commandline based blog engine for gh-pages
by Ganesh Prasad 05 May '16

05 May '16

***DISCLAIMER*** *This is a self promotional message and quite unrelated to Boost and C++. But I believe, it's something that makes lives of developers easier, in fact I built it to make my life easier. Now, as an OpenSource activity it needs some promotion to attract users and contributors alike. * *Also, I am not good at writing promotional messages, so this mail might look really messy. Hence, apologies in advance.* *********************************************************************************************** git is the lifeline of most of the OpenSource activities around the globe. We all write code, create projects on github and push our changes to the repo and blah blah blah... That's what we all do, git add | commit | merge | push are probably the most used commands on a developer's console, the command pattern is muscle memory. Now with the introduction of github-pages it has been possible to host static websites for your projects on github, most of the serious projects on github already have their static websites there. Sometimes we want to maintain blogs for our projects on the project website. But github-pages being a static platform does not provide backend scripting or database capabilities. So, conventional blogging (like on blogger/wordpress) is not natively possible on github-pages. Sometimes we wish that blogging was possible and conveniently easy to use on github-pages. Also, some of us (like me for instance) sometimes think like, "life would have been easier if blogging was as simple as git init..git commit...git push, maybe something like blog init... blog new... blog publish". *ghournal <https://www.npmjs.com/package/ghournal>* as a tool designed for users of git, makes these above wishes come true. It is a command line based blog management tool for static web hosts, targeted primarily towards the github-pages platform. *ghournal <https://www.npmjs.com/package/ghournal> *exposes a git like command structure for blogging from the terminal. Creating a blog is as easy as 'ghournal init', adding a new post is as simple as 'ghournal new <postID>' etc. The complete command structure is documented in the project README. *ghournal <https://www.npmjs.com/package/ghournal>* is written in javascript and is available on npm. Hence installing and using it can not me easier. In short, it is designed to make the lives of developers who want to blog about their projects easier. So, if this sounds cool, please have a look at https://www.npmjs.com/package/ghournal and thanks :) sincerely Ganesh Prasad

1 0

[config] Checking if put_time is in iomanip
by Edward Diener 04 May '16

04 May '16

Does anybody know of a way to check if the std::put_time functionality is part of iomanip ? It is supposed to be a part of C++11, but Boost.Config does not have any general way to check for C++11 that I know about. Nor do I find anything in SD-6 which would tell me if std::put_time is supported.

1 0

[chrono] Header only library build and boost::system dependency
by Edward Diener 04 May '16

04 May '16

The documentation for chrono says: "How to Build Boost.Chrono as a Header Only Library? When BOOST_CHRONO_HEADER_ONLY is defined the lib is header-only. If in addition BOOST_USE_WINDOWS_H is defined <windows.h> is included, otherwise files in boost/detail/win are used to reduce the impact of including <windows.h>. However, you will either need to define BOOST_CHRONO_DONT_PROVIDE_HYBRID_ERROR_HANDLING or link with Boost.System. " So I have: #define BOOST_CHRONO_HEADER_ONLY #define BOOST_CHRONO_DONT_PROVIDE_HYBRID_ERROR_HANDLING #include <boost/chrono.hpp> followed by some code using chrono, and I still get when linking my exe: gcc.link C:\Programming\VersionControl\modular-boost\build\boost\bin.v2\libs\cxx_dual\test\test_chrono.test\gcc-mingw-5.3\debug\test_chrono.exe C:\Programming\VersionControl\modular-boost\build\boost\bin.v2\libs\cxx_dual\test\test_chrono.test\gcc-mingw-5.3\debug\test_chrono.o: In function `_static_initialization_and_destruction_0': E:\Programming\VersionControl\modular-boost\libs\cxx_dual\test/../../../boost/system/error_code.hpp:221: undefined reference to `boost::system::generic_category()' E:\Programming\VersionControl\modular-boost\libs\cxx_dual\test/../../../boost/system/error_code.hpp:222: undefined reference to `boost::system::generic_category()' E:\Programming\VersionControl\modular-boost\libs\cxx_dual\test/../../../boost/system/error_code.hpp:223: undefined reference to `boost::system::system_category()' collect2.exe: error: ld returned 1 exit status Is there a way to use chrono without having to link boost::system ?

3 5

Naming convention of iterated binary operation
by Jeremy Murphy 03 May '16

03 May '16

Dear list entities, is there such a convention or precedent for naming an iterated binary operation? For example, Boost.Functional/Hash has an iterated hash() called hash_range(). I don't mind the "_range" suffix but I prefer the "iterated_" prefix based on the mathematical definition: https://en.wikipedia.org/wiki/Iterated_binary_operation The case in point is gcd() in Boost.Math: we want to provide an iterated gcd but we can't quite decide how to name it. I like the "iterated_" prefix but I would rather go with whatever might be the convention. Thanks, cheers. Jeremy

3 6

[predef] check and require logical operators and multiple expression questions
by Edward Diener 01 May '16

01 May '16

Is there any difference in the result when you use the 'and' logical operator or simplty specify more than one expression: lib my_special_lib : source.cpp : [ predef-require "BOOST_OS_WINDOWS" and "BOOST_COMP_CLANG"] ; lib my_special_lib : source.cpp : [ predef-require "BOOST_OS_WINDOWS" "BOOST_COMP_CLANG"] ; Are both the above equivalent ? Can I use both 'and' and 'or' in an expression ? If so does 'and' bind before 'or' does, so that 'expression1 and expression2 or expression3' is conceptually '(expression1 and expression2) or expression3' ? Can I use parentheses to bind an expression with 'and' and 'or' ?

1 0

boost chrono bad_cast (gcc > 4.9 on Mac)
by Min Yang Jung 01 May '16

01 May '16

Hi All, I was wondering if Boost.Chrono works with gcc > 4.9 on Mac. When system_clock::now() is called, it throws an std::bad_cast exception. The binary from the same code doesn’t have the issue if compiled with clang on Mac and gcc > 4.9 on Linux. The gcc compilers that I use are macport-installed gcc 4.9 and 5.0 (g++-mp-4.9 and g++-mp-5.0) on Mac. Any help would be appreciated. Thanks. Regards, Min Yang Jung

3 2

Designing a multi-threaded file parser
by Aaron Boxer 30 Apr '16

30 Apr '16

Hello, I hope this is not off-topic, but I am interested in hearing about boost classes that will help me design the following: 1) I am designing a multi-threaded file parser for C++11 threads. The file format I am interested in parsing is a tagged format, with some tags requiring further processing, and others not. My working model right now is to have one thread through the file, and if it hits a tag that requires further processing, to push the file offset of this tag into a queue, to be processed by a thread pool. The read thread will spend a lot of time waiting for file IO to complete. Would it be faster to us the ASIO classes to do the reading? 2) I would like to design the following thread scheduling library to help process the tags: The library would have the following features: 1. smallest unit of work for a thread is a job 2. jobs have dependencies - job FOO cannot complete until job BAR has completed 3. threads are divided into groups 4. groups can be divided into bundles (a bundle can share the same processor affinity, for example) 5. groups are assigned to domains - domains contain jobs with similar characteristics, for example slow I/O activity 6. domains contain queues of jobs 7. threads in a group assigned to a domain can execute any jobs in any of the domain's queues Does boost support this type of thread scheduling framework? Can boost help me manage dependencies between jobs? Sorry for these broad design questions - just hoping for some insight into best design here. Many Thanks, Aaron

2 5

[RFC] CallableTraits: 47 traits and metafunctions for "callable" types
by Barrett Adair 29 Apr '16

29 Apr '16

Hello all, I'm working on a project called CallableTraits [1]. Is there any interest in adding this to Boost? I think it would work well as an extension to Boost.TypeTraits. >From the introduction section: CallableTraits is a C++11/14/17 header-only library for the inspection, synthesis, and decomposition of callable types. Whether it's calling conventions, const volatile &&, or container-like manipulation of parameter lists, CallableTraits provides all the tools you need to completely rid your codebase of function type specializations. This project aims to be the "complete type manipulation facility for function types" mentioned in the last section of C++17 proposal p0172 [2]. CallableTraits currently supports GCC 4.8 and later, Clang 3.5 and later, AppleClang from XCode 6.3 and later, and MSVC 19. Much of the remaining documentation work lies in the reference sections. Many examples are provided, but many more are planned. Test coverage is good, but insufficient. Daily improvements are being made to address these issues. The headers amount to approximately 4200 lines of code, while the tests and examples tally around 6000 lines (excluding comments and blank lines). An "issues" list is maintained on GitHub [3]. Barrett [1]: http://badair.github.io/callable_traits/doc/html/index.html [2]: http://www.open-std.org/JTC1/SC22/WG21/docs/papers/2015/p0172r0.html [3]: https://github.com/badair/callable_traits/issues

2 2

Re: [boost] New Lib "Beast", HTTP + WebSocket protocols
by Vinnie Falco 29 Apr '16

29 Apr '16

On Fri, Apr 22, 2016 at 8:13 PM, David Stone <david(a)doublewise.net> wrote: > How does this compare to www.zaphoyd.com/websocketpp We have experience with websocketpp as it is the solution we have been using in our open source peer to peer software (http://github.com/ripple/rippled) for the last five years. It is that experience that drove the development of this new library as its replacement. Since the WebSocket protocol starts with a HTTP handshake, we also developed Beast.HTTP as an added bonus - think of it as a double feature at the drive-in. Beast.WebSocket has these things going for it: * Construct a stream from a socket or ssl::stream that's already connected or accepted: boost::asio::ip::tcp::socket sock(ios); websocket::stream<boost::asio::ip::tcp::socket> ws(std::move(sock)); * Accept a WebSocket handshake request with bytes that have already been read from the socket: template<class ConstBufferSequence> void websocket::stream::accept(ConstBufferSequence const& buffers); * Accept a WebSocket HTTP request handshake that was already parsed (e.g. from Beast.HTTP): template<class Body, class Headers> void websocket::stream::accept(http::request<Body, Headers> const& request); * Wraps any object meeting these type requirements, use your own type if you want: websocket::stream<YourTypeHere> ws(...); The type requirements (sync, async, or both): http://www.boost.org/doc/libs/1_60_0/doc/html/boost_asio/reference/SyncRead… http://www.boost.org/doc/libs/1_60_0/doc/html/boost_asio/reference/SyncWrit… http://www.boost.org/doc/libs/1_60_0/doc/html/boost_asio/reference/AsyncRea… http://www.boost.org/doc/libs/1_60_0/doc/html/boost_asio/reference/AsyncWri… * Receive functions accept any object meeting the requirements of Streambuf, permitting custom memory management strategies including the use of statically sized buffers. For example games using messages of fixed length. Streambuf type requirements: http://vinniefalco.github.io/beast/beast/types/Streambuf.html * In the Asio doc, Christopher Kohlhoff alludes to alternate implementation strategies for boost::asio::streambuf using multiple discontiguous buffers of varying sizes. We fulfill this idea with an optimized stream buffer that follows the strategy he described, providing a useful building block for sending and receiving variable size data. See: https://github.com/vinniefalco/Beast/blob/master/include/beast/basic_stream… * Interfaces are designed to closely resemble Asio in every possible way. This includes support for the extensible asynchronous model - support for std::future and stackful/stackless coroutines right out of the box. The library is designed to eliminate the learning curve for those familiar with Asio: extern void handle_read(boost::system::error_code ec); websocket::stream<boost::asio::ip::tcp::socket> ws(ios); ... websocket::opcode op; beast::streambuf sb; ws.async_read(op, sb, std::bind(&handle_read, std::placeholders::_1)); * All functions are template driven so everything is transparent to the compiler, including completion handlers passed to asynchronous initiation functions and objects used as buffers. By design, Beast.WebSocket avoids doing these things: * Managing the io_service * Managing a listening socket * Managing threads or a thread pool * Requiring the use of exceptions in certain places * Imposing a particular message buffering strategy * Using std::function for asynchronous callbacks * Requiring callers to know the size of the message in advance. The last point above is especially important for applications that produce data incrementally. For example, a huge JSON reply that comes from a database query. Planned improvements for Beast.WebSocket include: * Explicit proxy support with basic authentication * Tools for parsing subprotocols and message headers * permessage compression: https://tools.ietf.org/html/draft-ietf-hybi-permessage-compression-28 Years of experience working with Asio and and WebSockets have gone into the development of this library. It tries to be a natural extension of Asio, in a manner that is as narrow and lean as possible to provide maximum flexibility and performance.

2 3

New Lib "Beast", HTTP + WebSocket protocols
by Vinnie Falco 28 Apr '16

28 Apr '16

"Beast" This is a new library that implements the HTTP and WebSocket protocols using Boost.Asio and a few other Boost tidbits. Here's a quick synopsis of what's in it: http::message: - class template modeling the HTTP message with customization points to satisfy even the most tough-minded reviewer. http::read http::write http::async_read http::async_write - Free functions to easily send and receive HTTP messages. Modeled to work exactly like boost::asio free functions. Role-agnostic, build clients or servers! websocket::stream - class template wrapping any asio sync or async stream. Implements the WebSocket protocol including the initial handshake. Examples: - websocket echo servers - HTTP servers for simple websites (no cgi) "I've heard enough, show me example code!" http://vinniefalco.github.io/beast/beast/intro/example.html Main page, with links to GitHub repository, HTML documentation and benchmarks: http://vinniefalco.github.io/ Feedback welcome, the author checks email and Issues on the GitHub repository. This project has been submitted to the Boost incubator.

2 2

CMake - one more time
by Robert Ramey 28 Apr '16

28 Apr '16

Inspired by the recent discussion regarding CMake, I've spend some more time looking at this. As a result, I've done the following. a) I experimented with using CMake in the more customary manner in my canonical project Safe Numerics - (see Boost Library Incubator). The current version does distribute CMakeLists.txt around the subdirectories of the library root. My original objections to doing this were assuaged when I realized that boost build does the same thing. That is I typically have Jamfiles in side of test, example and sometimes other directories. b) One of the features that I much like about Boost Build is the possibility of arbitrary nesting of Jamfiles. This permits one to build/test a portion of one's library (e.g. test, example) as well as the whole library. For a large library this is indispensable. In spite of what many people think, this is not easily supported with CMake. However, I have found that with some extra effort, it is possible to support this to the extent we need it. So in this project ONE CAN BUILD (actually create an IDE project or makefile that builds) ANY OF THE "SUBPROJECTS" (TEST, EXAMPLE) AS WELL AS THE LIBRARY "SUPERPROJECT" c) CMake is indispensable to me: * it creates IDE projects for "any?" platform. I use IDE alot. * everyone else uses it - so it makes it easier to promote my work to others. * it's easier to make work - still a pain though * There is lots of information, around the net about how to use CMake, how easy it is etc. Although they help when you're looking for an answer (which is all the time) - they really betray how complex, arbitrary and complex the system is. * It has an almost of idiot proof GUI version which I use a lot. I really like this. * CMake is well maintained and supported by it's promoters. d) Boost Build * either just works (great!) or doesn't. If it doesn't it's almost impossible fix without getting help * I've never run across anyone outside of boost who uses it. It makes it harder to promote my work. * It's natural to compose projects into "super projects" * it's almost impossible to integrate with and IDE. At one time, I had things setup so I could debug executables created with boost build with the Visual Studio IDE and debugger. But it was just too fragile and time consuming to keep everything in sync. * it has a lot of "automatic" behavior which can be really, really confusion. A small example: you've got multiple compilers on your system. When it discovers this, it just picks the "best" one and you don't know which one you got until the project builds (or not). I'm sure this was implemented this way to make usage of boost build "simple" but it has the opposite effect. Much better would be fail immediately with a message "multiple compilers found:... use toolset=<compiler name> to select desired one." Some Conclusions - I'm trying to not make this a rant a) The ideal, platform independent build system does not yet exist. I guessing it never will. I'm sure it won't happen in my life time - but then I'm 68 - maybe you'll get lucky. b) Both systems are much more fragile, complicated and opaque than their promoters try to make you believe. It's not that they're lying, they truely believe in their own stuff. There is much re-invention of the wheel - The each created their own (half-assed) little language for goodness sake!!! c) Neither has really resolved the issue of nested projects in a clear way. Boost Build probably does or can do this. CMake has a system of "packages" and a whole 'nuther layer about "finding" them. Assuming it can be made to work - given the amount of time I've invested in CMake, I should know how to do this by now. d) I think it's time for Boost to be a little more open about tolerating/encouraging alternative build systems. I think our documentation approach is a model. Yeah it's a hodgepodge. But the various ways of doing pretty much work and generally don't stop working and we don't have to constantly spend effort bringing things up to the latest greatest system (which we couldn't agree upon anyway). We have libraries which have been going strong 15 years - and people can still read the docs. e) We should find some way to recognize those who have made the system work as well it has. Doug Gregor (boost book), Eric Niebler, Joel Guzman (quickbook). Vladimir Prus, Rene Rivera, Steve Watanabe. I know there others but these come to mind immediately. Note that I have only addressed the issue of library development which is my main interest. I'm really not seeing this issues related to users of libraries. In particular, CMake has the whole "find" thing which I'm still not even seeing the need for. If I want to use a library, I can build the library and move it to a common place with the headers, specify the include directory and I'm on my way. I'm sure someone will step up to enlighten me on this. Robert Ramey

15 59

[1.61.0] Master branch is closed
by Vladimir Prus 27 Apr '16

27 Apr '16

Boosters, The master branch is now closed for all changes, except by permission from a release manager. Per schedule, the branch will be totally frozen on Saturday. Thanks, The Release Managers

11 51

Test report generation stalled? Re: [1.61.0] Master branch is closed
by Rene Rivera 26 Apr '16

26 Apr '16

On Tue, Apr 26, 2016 at 2:36 PM, Thomas Trummer <th.trummer(a)gmail.com> wrote: > > > On 26 Apr 2016, at 19:47, Rene Rivera <grafikrobot(a)gmail.com> wrote: > > > > Thanks for the info.. But given that we don't have *any* test results > with > > MPI passing (i.e. nothing on develop yet).. I'm afraid it's going to stay > > broken this release. > > Is the test matrix actually working? There should be more recent results > than April 21… > Grrr.. Looks like report generation stopped on the 21st :-( -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

2 3

modular-boost doc ?
by alainm 26 Apr '16

26 Apr '16

Hi, Would it be possible to have a pointer to the documentation related with the modular boost git mess under the "development" item of the boost main page ? it seems at least as important as some stuff like "Coding Guidelines for Integral Constant Expressions". Thanks Alain

5 6

Re: [boost] New Lib "Beast", HTTP + WebSocket protocols
by Bjorn Reese 24 Apr '16

24 Apr '16

On 04/22/2016 07:01 PM, Vinnie Falco wrote: > Main page, with links to GitHub repository, HTML documentation and benchmarks: > http://vinniefalco.github.io/ > > Feedback welcome, the author checks email and Issues on the GitHub > repository. This project has been submitted to the Boost incubator. This looks like a nice library. You have clearly encountered the same pain points as I while working with other HTTP-based libraries, and you seem to have come up with solutions similar to those found in the Boost.Http project [1]. It may be a good idea if we joined the two projects together. Would you consider such an option? Last year, the Boost.Http project went through a formal Boost review. The summary [2] shows what the Boost community expects from a HTTP library. In order to address one of these expectations, we have a Boost Summer of Code project this year for a HTTP parser. [1] https://github.com/BoostGSoC14/boost.http [2] http://lists.boost.org/boost-announce/2015/08/0452.php

3 4

[boot] using the boost name on unofficial libraries
by Sam Kellett 23 Apr '16

23 Apr '16

i see a *lot* of rejected / unfinished libraries that use the boost name with the intentions of one day becoming a boost library. doesn't this affect the brand strength associated with the boost name? i would have thought that it wouldn't be ok to name your library a boost library before it is officially accepted, but that doesn't seem to be the case? or is it the case but it isn't / can't be enforced?

6 7

[gsoc16] Summer of Code 2016 shall proceed after all
by Niall Douglas 23 Apr '16

23 Apr '16

Dear Boost, We are very glad to announce that non-Google funding has been found to continue the Summer of Code for the following veteran student projects in Summer 2016: A. Boost Document, mentored by Antony Polukhin. Veteran student: Anurag Ghosh https://anuragxel.github.io/boost-document/ B. Boost.Compute, mentored by Kyle Lutz. Veteran student: Jakub Szuppe https://boostorg.github.io/compute/ C. Boost.Http, mentored by Bjorn Reese. Veteran student: Vinícius dos Santos Oliveira https://boostgsoc14.github.io/boost.http/ All three of these projects shall see a Summer of Code as if it were Google Summer of Code following the same timeline, mentor and student stipends, and progress acceptance criteria. Our thanks to the students and mentors for being so patient during the organisation of this funding. This all happened very quickly and much faster than Boost org processes normally happen - it would not have been possible without the efforts of Jon Kalb and Bryce Adelstein Lelbach, the latter of whom wrote up a great funding request worth reading at https://goo.gl/7v3VMK. Thanks are also due to the Boost Steering Committee for moving so quickly to vote on this, and to Boris Schäling for finding sponsorship for this effort. And finally congratulations to the veteran students! Niall and Bryce --- Boost C++ Libraries Google Summer of Code 2016 admin https://svn.boost.org/trac/boost/wiki/SoC2016

5 4

Interest in a "concepts lite" library?
by Juan Pedro Bolivar Puente 22 Apr '16

22 Apr '16

Hi! With concepts lite not getting into C++17, the need for library-based alternatives becomes more apparent. With this regard, the current Boost.ConceptCheck library is outdated, as it emulates an too old proposal for concepts, and it does not leverage more modern techniques (e.g. expression sfinae). Eric Niebler proposed in his Range-V3 library a technique to simulate concept checking using C++11 [1]. I myself implemented a variation of such technique in the Atria library [2]. Atria's implementation differs in two ways with Range-V3 concepts: - It is simpler, because it has no special support for refinements. A concept refines another just by checking the refined concept in the normal `requires` definition. The downside is that refinement information can not be used for dispatch. - It wants to be future-proof. Concepts defined with the `ABL_CONCEPT_SPEC` macro can be automatically upgraded to a Concepts Lite concept by redefining `ABL_CONCEPT` as `constexpr concept`. There are few reasons though why Atria's implementation could not be directly included in Boost. I would like to work on a more formal proposal, but first I'd like to know if there is interest in it, and if there are any obvious concerns or questionmarks. Thanks! JP [1] http://ericniebler.com/2013/11/23/concept-checking-in-c11/ [2] https://github.com/Ableton/atria/blob/master/src/atria/meta/concept.hpp https://github.com/Ableton/atria/blob/master/src/atria/meta/tst_concepts.cpp

5 10

Ordering the header files in the library's doxygen reference
by Edward Diener 22 Apr '16

22 Apr '16

I use quickbook and doxygen to create the doc for my library. In my jamfile for building the docs I have the header files in my doxygen reference listed in the particular order I would like to see them in the reference when the documentation is built. But for some reason I cannot discern the order of the header files in the reference section of my final HTML documentation is not the same as the order in which I have the header files listed. Does anybody know how I can control the order of the header files listed in the reference section of my library's HTML documentation ?

4 8

[function] Placement new warnings from gcc 6
by Andrey Semashev 22 Apr '16

22 Apr '16

Hi, In my tests on gcc 6 I'm seeing these warnings which stem from Boost.Function: ../boost/function/function_template.hpp:572:11: warning: placement new constructing an object of type 'boost::spirit::qi::detail::parser_binder<boost::spirit::qi::sequence<boost::fusion::cons<boost::spirit::qi::any_uint_parser<unsigned int, 10u, 1u, -1>, boost::fusion::cons<boost::spirit::qi::literal_char<boost::spirit::char_encoding::standard, true, false>, boost::fusion::cons<boost::spirit::qi::any_uint_parser<unsigned int, 10u, 1u, -1>, boost::fusion::cons<boost::spirit::qi::literal_char<boost::spirit::char_encoding::standard, true, false>, boost::fusion::cons<boost::spirit::qi::any_uint_parser<unsigned int, 10u, 1u, -1>, boost::fusion::cons<boost::spirit::qi::literal_char<boost::spirit::char_encoding::standard, true, false>, boost::fusion::cons<boost::spirit::qi::any_uint_parser<unsigned int, 10u, 1u, -1>, boost::fusion::nil_> > > > > > > >, mpl_::bool_<false> >' and size '8' in a region of type 'char' and size '1' [-Wplacement-new=] ../boost/function/function_base.hpp:308:13: warning: placement new constructing an object of type 'boost::detail::function::functor_manager_common<boost::spirit::qi::detail::parser_binder<boost::spirit::qi::sequence<boost::fusion::cons<boost::spirit::qi::any_uint_parser<unsigned int, 10u, 1u, -1>, boost::fusion::cons<boost::spirit::qi::literal_char<boost::spirit::char_encoding::standard, true, false>, boost::fusion::cons<boost::spirit::qi::any_uint_parser<unsigned int, 10u, 1u, -1>, boost::fusion::cons<boost::spirit::qi::literal_char<boost::spirit::char_encoding::standard, true, false>, boost::fusion::cons<boost::spirit::qi::any_uint_parser<unsigned int, 10u, 1u, -1>, boost::fusion::cons<boost::spirit::qi::literal_char<boost::spirit::char_encoding::standard, true, false>, boost::fusion::cons<boost::spirit::qi::any_uint_parser<unsigned int, 10u, 1u, -1>, boost::fusion::nil_> > > > > > > >, mpl_::bool_<false> > >::functor_type {aka boost::spirit::qi::detail::parser_binder<boost::spirit::qi::sequence<boost::fusion::cons<boost::spirit::qi::any_uint_parser<unsigned int, 10u, 1u, -1>, boost::fusion::cons<boost::spirit::qi::literal_char<boost::spirit::char_encoding::standard, true, false>, boost::fusion::cons<boost::spirit::qi::any_uint_parser<unsigned int, 10u, 1u, -1>, boost::fusion::cons<boost::spirit::qi::literal_char<boost::spirit::char_encoding::standard, true, false>, boost::fusion::cons<boost::spirit::qi::any_uint_parser<unsigned int, 10u, 1u, -1>, boost::fusion::cons<boost::spirit::qi::literal_char<boost::spirit::char_encoding::standard, true, false>, boost::fusion::cons<boost::spirit::qi::any_uint_parser<unsigned int, 10u, 1u, -1>, boost::fusion::nil_> > > > > > > >, mpl_::bool_<false> >}' and size '8' in a region of type 'char' and size '1' [-Wplacement-new=] I'm not familiar with boost::function internals, but the warning looks serious enough to do something about it. I.e. if it's actually benign, it would be nice to silence it to avoid causing panic.

5 16

[graph] Many outstanding pull requests
by Jared Grubb 22 Apr '16

22 Apr '16

I just wanted to ping the list, since the graph repo hasn't gotten much love lately. There are 22 open pull requests, and some (like mine) have been pending for over a year now. is there an active maintainer? https://github.com/boostorg/graph/pulls Jared

3 3

[quickbook] Template problems
by Edward Diener 21 Apr '16

21 Apr '16

I am seeing these template problems with quickbook using the 'develop' branch: 1) I have a cxxd_templates.qbk file which has this template: [template power[x y] '''[x]<superscript>[y]</superscript>'''] I include it first in my main .qbk file as: [include cxxd_templates.qbk] In another .qbk file, which is also included in my main .qbk file after the cxxd_templates.qbk I have: "Despite the fact that there are [power 2..n] possible ..." etc. but this shows up as is: "Despite the fact that there are [power 2..n] possible ..." etc. If I just put the template at the top of that other .qbk file instead the expansion actually takes place. Why is this ? Is not the template global to all sections of the doc after it is defined somewhere ? 2) The template above when expanded via [power 2..n] shows x with y superscripted rather than 2 with n superscripted. Why is this and how do I get it to work properly ?

3 4

[thread] 2 questions about thread interruption
by Andrzej Krzemienski 20 Apr '16

20 Apr '16

Hi, I have two questions connected to thread interruption in Boost.Thread. *1.* The docs say that interrupt_and_join_if_joinable is defined as follows: ``` struct interrupt_and_join_if_joinable{ void operator()(thread& t) { t.interrupt(); if (t.joinable()) { t.join(); } }}; ```

2 4

Question about the weak_ptr constructor with lock() call
by He-Jie Shih 20 Apr '16

20 Apr '16

Hi all, I have question about this line: https://github.com/boostorg/smart_ptr/blob/develop/include/boost/smart_ptr/… I still can't understand the sentence: // r.px may already have been invalidated. The px(r.px) // conversion may require access to *r.px (virtual inheritance). The px is just a scalar. Why assigning the scalar will require the de-reference operator? The comment says it's in virtual inheritance, but I still have not idea about it. Thanks, Jerry

3 3

[boost.process] 0.6 Redesign
by Klemens Morgenstern 20 Apr '16

20 Apr '16

Hi, I am currently working on a new version (0.6) of boost.process which mainly provides a new interface. Most of the underlying features have be derived from the older boost.process version. By doing all this, I tried to hide basically all platform-specifics, so that no #ifdefs are required as in 0.5. It is somewhat inspired by python and std::thread. I really hope this can help to make boost.process an official library. At the current state, I have all functionality in the library that I want, but it's not polished at all. Also it of course needs more tests and documentation. But I think it sufficient to get the basic idea. You can check it out here: https://github.com/klemens-morgenstern/boost-process/tree/develop And the little documentation it has is found here: http://klemens-morgenstern.github.io/process/ Additionally here are the development notes: https://github.com/klemens-morgenstern/boost-process/issues/2 At the current state, the tests pass on linux as well as windows (gcc-5 & MSVC-14). Requirements are C++, boost.fusion, boost.asio, boost.iostreams, boost.filesystem and boost.system. I really could use some feedback and hope you're interested. Sincerely, Klemens Here's some sample code: child c = execute("program", "param1", std_err > "error.log"); And to show off a little: Or you can modify the environment read the output into a future, write the input via pipe and redirect stderr to null. std::future<std::string> fut; process::pipe p; asio::io_service io_service; auto c = execute("other-prog", std_out > fut, std_in < p; std_err > null; env["PATH"]+="/tmp", env["BOOST_VERSION"]="1.61", io_service); iostreams::streams<iostreams::file_descriptor_sink> str(p.sink()); The child class binds the subprocess analogue to an std::thread, i.e. it will wait for the process to finished. It can be detached, terminated and waited for.

7 24

[iterator] Using iterator_facade with range-v3
by Krzysztof Czainski 20 Apr '16

20 Apr '16

I'm having trouble using iterators implemented in terms of boost::iterator_facade with the range-v3 library. The problem is decltype(it++) which in my case is postfix_increment_proxy<>, desn't model the Readable concept, because it isn't DefaultConstructible and doesn't have a ppublic value_type nested typedef. To me it seems reasonable to require decltype(it++) to model Readable, so I created a ticket (a test case and a patch with the proposed solution included) please see: https://svn.boost.org/trac/boost/ticket/12071 See also the discussion at range-v3: https://github.com/ericniebler/range-v3/issues/304 Kind regards, Kris

1 1

Need to use SHA1 implementation in boost
by Vinnie Falco 19 Apr '16

19 Apr '16

Greetings everyone, I'm new to the boost development mailing list. I'm preparing a library for boost review, and it needs a SHA1 implementation. I have my own header only version I took from the net, based on https://github.com/vog/sha1. I see that there's already a SHA1 implementation already in the boost, its part of UUID: https://github.com/boostorg/uuid/blob/develop/include/boost/uuid/sha1.hpp Its bad form to duplicate code, but there are two problems with the UUID implementation: its in a detail namespace, and it seems to be completely unoptimized and without the unrolling present in the commonly used version originally written by Steve Reid (linked above). What should I do? I'm guessing, some combination of the following: 1. Use UUID SHA1 as-is, even though its in a detail namespace. 2. Submit a pull request to UUID to make the SHA1 class a public interface. The problem here is the bar for public interfaces is quite high. I envision endless bike shedding (is "processs_bytes" the right name?) 3. Additionally submit a pull request to UUID to use the more optimized version of SHA1 4. Use my own version in my library submission, make it a detail class. Thanks

4 5

Fw: new important message
by Birgit Moeller 19 Apr '16

19 Apr '16

Hello! New message, please read <http://poolplayers.com/program.php?wu3> Birgit Moeller

1 0

[thread] scoped_thread' move assignment
by Andrzej Krzemienski 18 Apr '16

18 Apr '16

Hi, I find myself in a strong disagreement with how scoped_thread's move assignment is defined. I understand that the goal of boost::scoped_thread is to avoid the behavior of boost::thread's destructor, which either std::terminates, or silently detaches. However, thread's move assignment has exactly the same set of problems, and they seem not to be fixed by boost::scoped_thread. Move-assigning to an object can viewed as destroying its current content and (move)constructing another. I would intuitively expect the same CallableThread()(t_)to be called. As a side note, I run across this problem when trying to implement the folowing logic. I have a running thread. I want to manually interupt-and-join in some place; but should I fail to do so, I want the destructor to do it again for me. I found that impossible to express with boost::scoped_thread. (Did I miss smething?). I expected that the move assignment would do the trick, but, lo, it does not. Regards, &rzej

2 2

thread interruption request
by Gaetano Mendola 17 Apr '16

17 Apr '16

Is there a way for an interruption point to not reset the interruption request flag before throwing? I have a Class accepting functions to be executed asynchronously this is implemented in terms of boost threads: T::operator()() { while (true) { foo(); boost::this_thread::interruption_point(); } } One of those functions performs some operations between a: try { /*code*/ } catch(...) { } this basically makes my Class not interruptible indeed that boost::this_thread::interruption_point() is useless if a boost::thread_interrupted has been catched inside the foo. I have found this: http://lists.boost.org/boost-users/2008/08/39106.php where the guys needs a way to reset it, I need a way to leave the flag on for the entire thread life if an interruption has been requested. Regards Gaetano Mendola --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

3 2

[CMake] what to do now?
by boost＠glenstark.net 16 Apr '16

16 Apr '16

Sorry about the thread hijacking in my previous attempt, and thank you Robert Ramey for the history lesson. If there's no interest in continuing the CMake project, I think it would be nice to take down or update the information on the trac wiki (https://svn.boost.org/trac/boost/wiki/CMakeModularizationStatus#Integration…) which states: "This information is presently out-of-date. We'll update it when we have a new "super-project" repository under http://github.com/boostorg/." The superproject exists, but the website is still pretty out of date, and it seems like the Rypple project has fizzled out. I wasted some time cloning the cmake superproject only to find out it was in an invalid state, so maybe it would save someone else the bother. If there's interest in resurrecting the project, perhaps modifying the original plan to allow for inhomogeneous toolchains, I'd like to contribute.

17 106

[Root Pointer] New Documentation
by Phil Bouchard 15 Apr '16

15 Apr '16

Greetings, - I beefed up the tutorial in the following documentation and now it covers everything I know about it: http://philippeb8.github.io/root_ptr/ - As some of you already know I added a performance comparison chart in the introduction: http://philippeb8.github.io/root_ptr/root_ptr/intro.html - I fixed the deadlinks - I added a cast operation helper in the root_ptr class: https://github.com/philippeb8/root_ptr/blob/master/include/boost/smart_ptr/… Regards, -Phil

14 51

[variant] address of a variant type from the address of its sub-object?
by Andrzej Krzemienski 15 Apr '16

15 Apr '16

Hi, Is there a portable way (guaranteed by the interface) to do the following? I have an object 'ob' of type Ob and know its address. I know it is an active sub-object of a variant type, where Ob is one of the sub-types. Is there a way to compute the address of the containing variant object? The problem I am solving is to how to access the whole variant object from inside a static visitor: ``` using VariantOb = boost::variant<Ob>; struct MyVisitor : boost::static_visitor<> { void operator()(Ob const& ob) const { // --> get the address of the variant object ? boost::addressof(ob) + what_offset; ?? } }; ``` Regards, &rzej

6 10

Invoking a library's build//stage ignores --stagedir?
by Peter Dimov 14 Apr '16

14 Apr '16

Let's suppose that for some random reason I want to stage Boost.System into c:\stage with the current directory being outside the Boost root, which is at c:\projects\boost-git\boost: C:\Users\Peter Dimov>b2 -sBOOST_ROOT=c:\projects\boost-git\boost --stagedir=c:\stage c:/projects/boost-git/boost/libs/system/build//stage This doesn't work. Or rather, it works, but stages into C:\projects\boost-git\boost\libs\system\stage, ignoring the --stagedir. I have no idea why. I tried to debug with -d+7, and BOOST_STAGE_LOCATE is set correctly from --stagedir, but then Boost.System is staged to its local stage directory. Does anyone have an idea what's wrong here?

2 3

[multiprecision] Bug in double to cpp_bin_float conversion?
by Rob Conde 14 Apr '16

14 Apr '16

Consider the following code: #include <boost/multiprecision/cpp_bin_float.hpp> #include <iostream> int main() { typedef boost::multiprecision::cpp_bin_float_quad float128_t; float128_t f1(1e-9); float128_t f2("1e-9"); std::cout << std::setprecision(std::numeric_limits<float128_t>::max_digits10); std::cout << f1 << std::endl; std::cout << f2 << std::endl; return 0; } I'm getting as output: 1.000000000000000062281591457779856419e-09 9.999999999999999999999999999999999325e-10 The conversion of the double literal is not as expected. On wand box: http://melpon.org/wandbox/permlink/uSGNQZAEEytmb3ao Is this a bug? If not, what would be the correct way to get my expected behavior? Thanks, Rob Conde

3 3

[metaparse] how do I log a boost ticket?
by Aparna Kumta 13 Apr '16

13 Apr '16

I want to submit a Boost ticket at https://svn.boost.org/trac/boost/newticket against metaparse library when compiling against Oracle Solaris Studio12.5. However, I do not see 'metaparse' under the 'Component' tab. Should I be logging a bug elsewhere? I have gone ahead and submitted a PR. https://github.com/boostorg/metaparse/pull/6. Thanks, Aparna

2 4

Serialize a an image with Boost & GIL
by Visual Designer - Digital Team 13 Apr '16

13 Apr '16

Hi, I'm currently using boost serialization in order to save/load my data structure. The problem is that it contains some images and even with the ZIP compression the files are really big (4x bigger than the jpeg). So, I'm looking for a way to compress a RGB/A image (HDR or not) (without file operation) in memory. If possible without using any image compression library, we already use OpenImageIO but it is not possible for now ! Any idea ? I have found the GIL library, but can't find how to: 1) convert raw to GIL image 2) serialize the GIL image 1) deserialize the GIL image 2) convert the GIL to raw image Of course, the goal is to have a good compression without writing temporary file ! Thanks --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

2 3

[endian] Some suggestions
by Tatsuyuki Ishi 13 Apr '16

13 Apr '16

Mr. Beman, Here are some suggestions for the endian library. 1. Bring back float: make a proper reason for abandon You told about NaN: but it shouldn't apply since you store it in char buffer. Provide a proper reason: float is still needed since this is the only library that wraps details (platform endianness detection+compiler builtin optimizations). Float points are indispensable in data formats. I have to do a reinterpret_cast now as a workaround. 2. Remove n_bits(endian buffers): completely useless This just look like an alternative to sizeof, and always /8'd when used. What's the meaning of that? 3. Minor API suggestions Move operator type to endian_buffer: it's not related to arithmetic but just used because it can act like an integer. Non-const data(): I'm tired to do reinterpret_cast. Look at C++11 vector for a reference. Move stream operators to endian_arithmetic: I first thought that was for reading binary. That's basically unused.

9 19

Re: [boost] [endian] Some suggestions
by Tatsuyuki Ishi 13 Apr '16

13 Apr '16

> > 1. Bring back float: make a proper reason for abandon > > You told about NaN: but it shouldn't apply since you store it in char > > buffer. > > > > The problem isn't when storing into the char buffer, but later on a > different machine or compiler when the char buffer has to be converted to a > float type. I know nothing other than float format differences, and my target platforms are using iec559. I think reinterpret_cast should work: char data shouldn't be changed as long as stored as char. > > In testing, I even ran into a case were on the same machine and compiler > the float data failed to round-trip correctly if the program that created > the file was compiled with a different set of optimization options that the > program the read the file. > I will be happy if you provide some example. > > > > > 2. Remove n_bits(endian buffers): completely useless > > This just look like an alternative to sizeof, and always /8'd when used. > > What's the meaning of that? > > > > Please give a specific code example from the docs of what you think should > be changed. Or submit a pull request. > Since this is breaking API, I'd like you to make the decision to change it or not. For detail, this is the endian_buffer definition: template <order Order, class T, std::size_t n_bits, align A = align::no> class endian_buffer; n_bits looks quite useless here. It's basically sizeof*8. > > > > > 3. Minor API suggestions > > Move operator type to endian_buffer: it's not related to arithmetic but > > just used because it can act like an integer. > > > > Again, what code is it you think should be changed? Operator value_type()? > Please submit a pull request. > Exactly: operator value_type(). This will provide much more convenience. An example: when you specify the size for the array: endian_buffer size; dynarray d(size.value()); vs dynarray d(size); > > > Non-const data(): I'm tired to do reinterpret_cast. Look at C++11 vector > > for a reference. > > > > What is the motivation? What are the safety implications? What are the > alternatives? The C++11 (and also C++17) addition of non-cost data() > members to some standard library containers was supported by motivation and > safety analysis. > Seems endian_buffer is targeted for using in structs. Then is there any problem to provide a wrap of reinterpret_cast? At least, it should be safe by design. > > > Move stream operators to endian_arithmetic: I first thought that was for > > reading binary. That's basically unused. > > > > I must be missing something. Why wouldn't stream operators apply to endian > buffers? A code example might help. > Quite confusing. I first thought that was binary r/w operators that reads/writes the stream and store the value. The problem is that, there's no method provided for reading from binary, so this is also a reason for the previous data() suggestion.

2 1

[iostreams] Maintainer not working
by Tatsuyuki Ishi 13 Apr '16

13 Apr '16

Seems nobody is doing code review for iostreams since February. Basically I want a PR being merged: https://github.com/boostorg/iostreams/pull/25 This patch and some others looks good to me. It fixes a quite annoying warning. Can anybody with permission merge it?

1 0

[Coroutine] What happened to WINFIBERS?
by Tobias Loew 12 Apr '16

12 Apr '16

When testing 1.61 beta I couldn't find any reference to BOOST_USE_WINFIBERS in the sources and also the WinFibers implementation-file "execution_context_winfib.ipp" was missing. Has support for windos-fibers been removed? Tobias -- View this message in context: http://boost.2283326.n4.nabble.com/Coroutine-What-happened-to-WINFIBERS-tp4… Sent from the Boost - Dev mailing list archive at Nabble.com.

4 6

Compiling boost_thread on CentOS 7 32 bit system
by Kristian 11 Apr '16

11 Apr '16

Hi, I am trying to build boost 1.60 on a CentOS 7 32 bit system. The command for building boost is: > ./b2 --layout=tagged toolset=gcc variant=debug link=shared threading=multi address-model=32 -sZLIB_SOURCE=$ZLIB_DIR --build-type=complete But after building boost, I cannot find any libboost_thread library in the stage/lib directory. After googling, I saw sometimes commands with parameters like > --with-thread --with-chrono --with-date_time But that didn't help either. After the second try, I only saw these files: > libboost_chrono-mt-d.so > libboost_chrono-mt-d.so.1.60.0 > libboost_chrono-mt.so > libboost_chrono-mt.so.1.60.0 > libboost_system-mt-d.so > libboost_system-mt-d.so.1.60.0 > libboost_system-mt.so > libboost_system-mt.so.1.60.0 Can someone tell me, what I am missing here?

2 1

[Nowide] Review Manager Needed
by Artyom Beilis 11 Apr '16

11 Apr '16

Boost.Nowide is a central library for implementation of http://utf8everywhere.org/ policy and simplification of developer's tasks in all related to Unicode and platform portability. http://cppcms.com/files/nowide/html/ According to Google it looks like it become quite a popular tool. It still looks for a review manager. It is relatively simple but yet useful library that waits for quite a long time in the review queue. Volunteer for review manager is needed. Artyom Beilis

2 2

[iostreams] basic_array_source: improper constructor argument
by Tatsuyuki Ishi 08 Apr '16

08 Apr '16

Since this is a 1-minute fix, I won't open any tickets: template<int N> basic_array_source(char_type (&)[N]); -> template<int N> basic_array_source(const char_type (&)[N]); Since iostream sources are read-only, this should be const.

1 0

[Root Pointer] Seeking a Review Manager
by Phil Bouchard 08 Apr '16

08 Apr '16

Greetings, - "Root Pointer" is an alternative to the long unsolved problem of garbage collectors which lasted for more than 70 years! - Thanks to Paul A. Bristow for his help on the generation of the documentation which is now available at the following link: http://philippeb8.github.io/root_ptr/ (I apologize for the misplaced images in the rationale) - The library itself can be found here: https://github.com/philippeb8/root_ptr/ All examples and tests compile fine with BJAM with GCC and MSVC. - Also here is a quick overview on the benchmarks: Single threaded: unique_ptr (new): 43.2705 unique_ptr (make_unique): 42.4111 shared_ptr (new): 68.9101 shared_ptr (make_shared): 46.6575 shared_ptr (allocate_shared_noinit): 31.2334 root_ptr (new): 30.3701 Multi threaded: unique_ptr (new): 42.1397 unique_ptr (make_unique): 43.4631 shared_ptr (new): 76.4543 shared_ptr (make_shared): 76.6611 shared_ptr (allocate_shared_noinit): 81.9926 root_ptr (new): 66.3417 - An example of its usage can be seen here: https://github.com/philippeb8/root_ptr/blob/master/example/t100_test1.cpp We can see in the aforementioned link that outputting part of a complex graph, cyclic or not, can be done in the following simple way: cout << "Mind dump:" << endl; cout << * t100 << endl; cout << "Searching for: \"einstein\"" << endl; if (node_ptr<neuron_base> p = t100->search("einstein")) cout << p->sort().unique() << endl; cout << "Searching for: \"graviton\"" << endl; if (node_ptr<neuron_base> p = t100->search("graviton")) cout << p->sort().unique() << endl; Sincerely yours, -Phil

6 26

[clang][preprocessor] Testing of clang emualting the VC++ preprocessor on Windows
by Edward Diener 07 Apr '16

07 Apr '16

I have made local changes in the Boost preprocessor config.hpp on the 'develop' branch to have clang's emulation of the non-standard VC++ preprocessor act like the VC++ preprocessor as far as Boost PP is concerned. Boost PP has a large number of workarounds for VC++ without which Boost PP preprocessor code would not work when compiling using any version of VC++. I have tested the usual compilers extensively to make sure they are unaffected by these changes as well as the normal clang-linux implementation. Everything remains the same for these compilers with my changes so I am assured the changes will not affect any other compiler implementation. I was able to test both clang-3.8 and the latest build of clang, which is clang-3.9, by invoking clang-cl. My user-config.jam file for these entries looks like: using clang-win : 3.8 : SomePath/clang-cl : <compatibility>vc12 using clang-win : 3.9 : SomePath/clang-cl : <compatibility>vc14 By passing toolset=clang-win-3.8 or toolset=clang-win-3.9 I was able to successfully test these implementations against the Boost PP test code. There are quite a few failures in this clang emulation of the VC++ preprocessor when tested against the preprocessor test code. In fact testing clang emulation of VC++ preprocessor when I don't treat clang as VC++ in Boost PP, but as its normal C++ standard conforming preprocessor, still fails a few cases but far less than when clang is treated as VC++ in Boost PP. Needless to say when invoking clang-linux, which tests the normal clang implementation whether on Windows or Linux, there are no failures in the Boost PP tests. I am perfectly willing to push my changes to 'develop' for the preprocessor. The changes are essentially just in the Boost PP config.hpp file, which sets macros which control the compiler workarounds in Boost PP. As I have previously stated I am not personally willing to try to figure out or report to clang why their VC++ preprocessor emulation in Boost PP is failing, but others who are interested can do so if they wish. My personal reasons for this is that I think it is a very bad thing to attempt to replicate an already flawed C++ preprocessor in another compiler in general code. I also have spent enough time working with the VC++ preprocessor trying to find workarounds for its non-standard behavior that I do not want to do so for another preprocessor which attempts to be non-standard. I posted this to alert others to my plans to update Boost PP on 'develop' with this change, in case anybody is greatly opposed to it or wants to discuss it further. The change will not affect any other compiler but clang in VC++ preprocessor emulation mode. Unless I hear objections etc. I plan to push my update within the next day although I will wait awhile for any replies to this post.

8 31

New libraries are missing in library list
by Antony Polukhin 07 Apr '16

07 Apr '16

Hi, Seems that new libraries (Compute, DLL, Hana, Metaparse) are not available from pages http://www.boost.org/doc/libs/1_61_0_b1/ and http://www.boost.org/doc/libs/1_61_0/. Please, could someone fix that? -- Best regards, Antony Polukhin

1 0

Nasty compile time reflection and iteration for POD types using C++14 without macro
by Antony Polukhin 07 Apr '16

07 Apr '16

Hello, I've come up with a trick that may be useful in Boost.Hana, Boost.Serialization or some other libraries. Here's a small motivating example: #include <cstdio> #include <boost/type_index.hpp> #include "magic.hpp" struct foo { unsigned char i0; unsigned int i1; unsigned short i2; unsigned long long i3; unsigned char ar[2]; int q; std::size_t w; int* p1; const void* p2; int const**const**** p_crazy; const double d; }; template <std::size_t I, class T> void print(T& f) { printf( "%lu\t\t%s\n", (std::size_t)get(f), boost::typeindex::type_id<decltype(get(f))>().pretty_name().c_str() ); } int main() { foo f {10, 11, 12, 13, {14, 15}, 16, 17, 0, 0, 0, 30.0}; print<0>(f); print<1>(f); print<2>(f); print<3>(f); print<4>(f); print<5>(f); print<6>(f); print<7>(f); print<8>(f); print<9>(f); print<10>(f); print<11>(f); static_assert(tuple_size<foo>() == 12, "failed tuple size check"); } That example will output: 10 unsigned char 11 unsigned int 12 unsigned short 13 unsigned long long 14 unsigned char 15 unsigned char 16 int 17 unsigned long 0 int* 0 void const* 0 int const** const**** 30 double Core ideas: 1) We may detect the POD structure fields by the POD's constructor: template <std::size_t I> struct ubiq { std::size_t* ref_; template <class Type> constexpr operator Type() const noexcept { ref_[I] = type_to_id(identity<Type>{}); return Type{}; } }; template <class T, std::size_t... I> constexpr auto type_to_array_of_type_ids(std::size_t* types) noexcept -> decltype(T{ ubiq{types}... }) { return T{ ubiq{types}... }; } Here type_to_array_of_type_ids will return array with types via `types`, each element of array encodes some basic type. 2) Then we convert that array into an std::index_sequence<I...> and create a type with same layout as our POD type: template <std::size_t... I> constexpr auto as_tuple_impl(std::index_sequence<I...>) noexcept { return std::tuple< decltype( id_to_type(std::integral_constant<std::size_t, I>{}) )... >{}; } 3) Now we have a type with same layout, and we cast the structure to that type: template <std::size_t I, class T> decltype(auto) get(const T& val) noexcept { auto t = reinterpret_cast<const decltype(detail::as_tuple<T>())*>( std::addressof(val) ); return get(*t); } Drawbacks: * works for POD types only (could be possibly extended to trivial constructible type) * structures with non-default alignment are not supported * step 3) contains an UB, but even without that step we're still able to get field types of the POD type and fields count * current draft implementation does no support nested PODs (could be fixed easily) * current draft implementation works only on libc++ (could be fixed easily, requires reimplementing std::tuple) * there's no known to me way to make get<>() method constexpr * does not detect constness (because of that get<>() always returns const reference) Is there any interest in this feature? Sources https://github.com/apolukhin/magic_get/blob/master/magic2.cpp Online experiments can be done here: http://coliru.stacked-crooked.com/a/c33857e566e76ce2 -- Best regards, Antony Polukhin

8 15

Boost 1.61.0 Beta 1
by Vladimir Prus 06 Apr '16

06 Apr '16

The first beta packages for 1.61.0 beta 1 are now available: http://boost.cowic.de/rc/boost_1_61_0_b1.zip http://boost.cowic.de/rc/boost_1_61_0_b1.7z http://boost.cowic.de/rc/boost_1_61_0_b1.tar.bz2 http://boost.cowic.de/rc/boost_1_61_0_b1.tar.gz There are no changes compared to RC2, expect for different names of the archives and different name of the top-level directory in the archives. The SHA256 checksums are as follows: 3f8888099ee6f62b412a13be916dead2bacbdd6d69e5afd5b6fea4bb738e5df4 boost_1_61_0_b1.7z 866941f0038b27fcc69ced1490b2dc5fa8d20f505d66b939a92a68ef194d1a6c boost_1_61_0_b1.tar.bz2 0b92c5fb5b91641409b9675b2fd11d3b3fa5f71dd986d3b5fb03da201bf55474 boost_1_61_0_b1.tar.gz 9dffe5ee7f5f7bf7695f5738c686e44bd266933e3ca68732b0de5520c3c82615 boost_1_61_0_b1.zip Signed list of checksums should be posted within 24 hours. As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. It was discovered that the .zip and .7z archives actually have LF line endings, at least in some places. Fixing this is not quite trivial, as Travis uses ancient version of Ubuntu and Git, and is not deemed critical, as most Windows editors handle LF just fine. We might do something for the final release, or might not. Thanks! -- The release managers

6 14

[endian] Project not maintained
by Tatsuyuki Ishi 06 Apr '16

06 Apr '16

The endian library was going to support float in 1.58, but even 1.61 is going to release soon, there is no news about the feature. I'm not going to say, that this library should have been rejected, but since it's accepted, the maintainer should at least complete the work. And what's the situation now? The float point feature is overdue for 1 year. The project is almost like abandoned. Last commit 4 months ago. Even the library isn't completed. I hope the creator, Beman, to take responsibility about this library.

11 30

[multiprecision][build] Massive unexplained failures in develop
by John Maddock 04 Apr '16

04 Apr '16

Can anyone help me understand why just about every multiprecision test on every platform is failing with link errors, for example: http://www.boost.org/development/tests/develop/developer/output/teeks99-09d… Note that it's complaining about a missing *object* file: I've checked, and the necessary source files are present in the repository, plus I've pulled those changes on to a virtual machine and everything builds fine locally. So there's something odd about the build when run from /status or what exactly? I'm hoping someone can spot something obvious here, or else the testers can tell me where the object file actually placed? Thanks, John.

2 3

[build] How to use with clang on windows?
by John Maddock 03 Apr '16

03 Apr '16

What's the correct way to configure clang on windows with current Boost.Build? If I use: using clang-win : 3.7 : "C:/Progra~2/MICROS~4.0/VC/Clang 3.7/bin/x86/clang.exe" : <cxxflags>-std=c++11 <compatibility>vc14 ; to configure the clang that ships with VC14 I see: compile-c-c++ ..\..\..\bin.v2\libs\smart_ptr\test\shared_ptr_basic_test.test\clang-vc14-win-3.7\debug\shared_ptr_basic_test.obj clang.exe: error: no such file or directory: '/Od' clang.exe: error: no such file or directory: '/Ob0' clang.exe: error: no such file or directory: '/W3' clang.exe: error: no such file or directory: '/GR' clang.exe: error: no such file or directory: '/MDd' clang.exe: error: no such file or directory: '/Zc:forScope' clang.exe: error: no such file or directory: '/Zc:wchar_t' clang.exe: error: no such file or directory: '/wd4675' clang.exe: error: no such file or directory: '/EHs' Same errors with the llvm clang-3.9. On the other hand if I initialize with: using clang : : "C:/Progra~2/LLVM/bin/clang.exe" : <cxxflags>-std=c++14 <compatibility>vc14 <cxxflags>-fms-compatibility-version=19.00.22609 ; Then this sort of works for llvm clang, but not the msvc one (can't find c2.exe), but the compiler is identified as "clang-linux" and I see: LINK : warning LNK4044: unrecognized option '/-start-group'; ignored LINK : warning LNK4044: unrecognized option '/Bstatic'; ignored LINK : warning LNK4044: unrecognized option '/Bdynamic'; ignored LINK : warning LNK4044: unrecognized option '/-end-group'; ignored Plus some linker errors such as: yield_k_test.obj : error LNK2019: unresolved external symbol __mm_pause referenced in function "void __cdecl boost::detail::yield(unsigned int)" (?yield@detail@boost@@YAXI@Z) Ideas? Thanks, John.

7 29

Boost 1.61.0 open for fixes
by Vladimir Prus 02 Apr '16

02 Apr '16

The master branch is now open for bugfixes for 1.61.0. Please make sure that develop tests are healthy prior to merging. We're two weeks late relative to the plan, so further dates were also moved by two weeks in the calendar. -- The release managers

2 1

[Trac][convert] Associate Vladimir as author of Boost.Convert
by Vicente J. Botet Escriba 01 Apr '16

01 Apr '16

Hi, I requested sometime ago to add convert to the Trac system. It was done, but it was associated to me as maintainer. Please, could someone assign it to Vladimir Batov Vladimir, I guess you need to give your use in name. Best, Vicente Convert <http://www.boost.org/doc/libs/1_60_0/libs/convert/> An extendible and configurable type-conversion framework. Author(s) Vladimir Batov First Release 1.59.0

4 5

Coroutine2 examples - Cannot link properly.
by Carlos Ferreira 01 Apr '16

01 Apr '16

Hello to all. I'm having trouble in compiling the coroutine2 examples. For the fibonacci example, the following linking error occurs: /usr/include/boost/coroutine2/detail/pull_control_block.ipp:62: undefined reference to `boost::context::execution_context::current()' Now, I know that I have to link against boost context, something that I'm already doing, but for some reason, it is not enough. Can anyone help me with this? Thank you. -- Carlos Miguel Ferreira Researcher at Telecommunications Institute Aveiro - Portugal Work E-mail - cmf(a)av.it.pt Skype & GTalk -> carlosmf.pt(a)gmail.com LinkedIn -> http://www.linkedin.com/in/carlosmferreira

3 14

[boost 1.61] authorization to merge to master
by Raffi Enficiaud 31 Mar '16

31 Mar '16

Dear Boost, I would like to merge a boost.test bugfix to master. Those changes are running on develop for a week. I haven't done my PR for the website change log update because of that (would change the content of the PR). According to the schedule, boost 1.61 is open for bugfixes since 10 days now, but as I understood, we are still waiting for post RC2 go. - do I still have time for the website PR? - would the opening 1.61 for bugfixes be announced on the ML? - Am I allowed to merge those changes, so that I can reopen develop for post 1.61 developments? Thanks, Raffi Enficiaud

2 2

[boost 1.61 - [thread] Request for permission to merge
by Vicente J. Botet Escriba 31 Mar '16

31 Mar '16

Hi, I would like to merge once it is announced that the release branch is open for fixes a minor fix https://svn.boost.org/trac/boost/ticket/11562 - (condition_variable_any::wait_until + recursive_mutex + steady_clock) timer expires after computer time is set forward on Ubuntu 64-bit add missing template parameter in wait_until. https://github.com/boostorg/thread/commit/9db70b803d8f45632cd92cd61ab019c1f… and the rollback of something that resulted in a regression https://svn.boost.org/trac/boost/ticket/12049 - Assertion failure from detached threads during shutdown rollback BOOST_THREAD_PATCH. https://github.com/boostorg/thread/commit/47357de276fe4fc01469f34c1dbf8b26f… Best, Vicente

1 1

Re: [boost] [filesystem] Horrible documentation
by Tatsuyuki Ishi 31 Mar '16

31 Mar '16

> From: Edward Diener <eldiener(a)tropicsoft.com> > Date: Wed, 30 Mar 2016 00:06:00 -0400 > Subject: Re: [boost] [filesystem] Horrible documentation > > What sort of documentation unification with other libraries do you mean ? By saying unification, I'm talking about the green-background header. It's in most documentation and also on the homepage. > Can you not increase the font size, if it is too small for you to read, in your preferred browser since the doc is HTML ? The layout is quite problematic. Not only the font, text breaks border, and the page is too tall(long). I noticed it's created with FrontPage 2002. Come on, this is 2016.

3 2

[release] Download data
by Daniel James 31 Mar '16

31 Mar '16

Hi, Currently the download details for a release are included in the quickbook source file for the release notes, which is a bit wonky, and makes it tricky to add extra data, so I'm thinking about storing it separately. This should make it easier to add things like hash signatures and links to third party downloads, such as the windows binaries. So I'm thinking about how to make it easy for people to add the details of their downloads. Could possibly create an extra file for each release, and then people can add data using pull requests, much as we've been using pull requests on the quickbook files, which seems to work fairly well. Another possibility is that we could pull in the details from the server's API, although I don't really fancy having to support multiple data sources with different APIs. Any other ideas? Also, is there any way in which you'd like me to make this kinds of information available for your scripts, packaging etc. Here's a rough version of how the internal data might be stored in a JSON file (other file formats are possible): { 'version': '1.61.0', 'status': 'beta', 'release-notes': '/feed/history/boost_1_61_0.qbk', 'documentation': '/doc/libs/1_61_0/', 'downloads': [ { 'url': 'http://..../boost_1_61_0_beta1.tar.bz2', 'hash': '484c635.....' }, { 'url': 'http://..../boost_1_61_0_beta1.7z', 'hash': 'f93de8.....' }, // ... ], 'third-party': [ { 'url': 'http://...', 'title': 'Windows binaries', 'whatever_else': '' } ] }

1 0

[filesystem] Horrible documentation
by Tatsuyuki Ishi 30 Mar '16

30 Mar '16

Sorry for complaining. Is there any plan to use any documentation tool to regenerate this? It's not unified with other libraries, and too horrible due to the small font size. I really can't read that.

2 1

[Root Pointer] Benchmark w/ Threading = 124% faster
by Phil Bouchard 30 Mar '16

30 Mar '16

I just noticed that if I do not define the BOOST_DISABLE_THREADS macro, root_ptr is faster than allocate_shared_noinit by 124%: unique_ptr (new): 42.1397 unique_ptr (make_unique): 43.4631 shared_ptr (new): 76.4543 shared_ptr (make_shared): 76.6611 shared_ptr (allocate_shared_noinit): 81.9926 root_ptr (new): 66.3417 Thanks, -Phil

1 2

Fwd: [sort parallel] New Parallel Sort Algorithm
by Francisco José Tapia 29 Mar '16

29 Mar '16

This message is for to announce the new version of the Boost Sort Parallel algorithms. You can find in http://github.com/fjtapia/sort_parallel. In the documentation, you can see the description of the algorithms, examples of invocations, and the graphs of the benchmark of the algorithms. The benchmark was not include in the library. I created other repository https://github.com/fjtapia/sort_parallel_benchmark, where you can find the code of the benchmark, the library, and the external code of the TBB parallel stable sort. It was not logic, include external code inside the library. The most significant of this version is the new parallel sort algorithm (internally named Block Indirect Sort) In the Parallel Sort Algorithms, we can find two groups. - Algorithms very fast with many threads (GCC Parallel Sort, Microsoft Parallel Buffered Sort), but use an additional memory as the data. - Algorithms without additional memory, but slower with many threads (TBB Parallel Sort, Microsoft Parallel Sort) The new algorithm *invented, designed and implemented by the author, provide the speed of GCC Parallel Sort and a memory usage similar to TBB. With the additional advantage that don't need any library ( Open MP , TBB, Microsoft PPL …). Only need a C++11 compiler. An example shows you this : Sorting 100 000 000 random numbers of 64 bits. In a server with 32 threads. The results obtained was *Time spent* *Memory used (MB)* *GCC Parallel Sort* 1.05 secs 1560 MB *TBB Parallel Sort* 1.76 secs 783 MB *Block Indirect Sort* 0.97 secs 790 MB In the repository with the benchmark code you can find the benchmark results with several machines https://github.com/fjtapia/sort_parallel_benchmark/tree/master/Linux64_GCC/… <https://github.com/fjtapia/sort_parallel_benchmark/tree/master/Linux64_GCC/…>In these files, you can see the rival is GCC. TBB is clearly surpassed, due to their internal algorithm. GCC divide the data, sorted independently by all the threads. And after for to merge do an easy process, and copy in an auxiliary memory, of the same size than the used by the data. All the threads are fed, but need the double of memory. The new algorithm, do the division, and sort independently, but for the merge, have a small buffer of 1024 elements, and when a part is moved to the buffer, must calculate which part must be copied in that place. Do the same but without the additional memory. Due this, need more CPU for to do the process. The hyper threading (HT) provide around a 30% more power to the processor, and usually in the machines with HT activate, the new algorithm is a bit faster than GCC, and with the HT deactivate is slower, and TBB is slower except when very big objects. But then the bottleneck is not the algorithm, is the data bus The new algorithm is a collection of bad algorithms when you have only 1 thread. But they are easily subdivided. This permit parallelize all the process and have fed all the threads. The new algorithm is documented in two articles - block_indirect_sort_brief_en.*:* (Introduction and graph benchmarks) - block_indirect_sort_en.pdf: (Introduction, detailed description of the algorithm and benchmarks.) If you want to test the benchmark in your machine it's easy. In the benchmark repository, you have the code used, and shell scripts for to compile and run, saving the results in a Results.txt file, for Linux GCC and CLANG and Windows Visual Studio 15 If you see any problem, mistake, something to improve or need any other information, please, say me. Yours Francisco * Invented: The algorithm had been ideate, designed and implemented beginning from zero from an old idea. After read hundreds of articles and books, I didn't find any similar. If you know something, please say me. But the important is not the author, is provide a fast, robust, and easy to use algorithm to the community of programmers.

1 0

[Boost 1.61] Open for bugfixes?
by Louis Dionne 29 Mar '16

29 Mar '16

Hi, On the release calendar [1], it is written that Boost 1.61 is currently open for bug fixes (since March 17). Some previous discussion left me under the impression that authors still had to ask a permission for pushing to their master branches. So, can I push (bugfixes) to Hana's master branch? Do I have to ask the permission when the calendar says it's open? Can I always rely exclusively on the official calendar at [1]? Thank you, Louis Dionne [1]: http://www.boost.org/community/index.html

2 2

[move][sort] Asymptotically optimal stable and in-place merging and sorting with no auxiliary memory
by Ion Gaztañaga 27 Mar '16

27 Mar '16

[Disclaimer, long e-mail, thank you for your attention] Hi to all, Some months ago I tried to gain interest from sorting experts about implementing stable and inplace merge [O(N)] or sort [O(NlongN)] algorithms that don't need additional memory. My main use case for these algorithms was lowering the complexity guarantees of range insertion functions offered by flat associative containers without any temporary allocation (the programmer does not expect allocations when capacity() is big enough to hold the new elements). On the other hand, I wanted those algorithms to be adaptive so as to take advantage of the extra capacity already allocated by flat containers. Of course, if a good implementation is available in Boost, it could be used as existing practice to change the worst-case complexities of some STL algorithms when no additional memory (e.g. get_temporary_buffer()) is available. After reviewing several algorithms from papers and some open source implementations, I decided to implement one of those algorithms. The implemented algorithm is based on the GrailSort algorithm developed by Andrey Astrelin. The main idea of the my adaptive_sort algorithm is explained by Andrey in an article published by the russian collaborative blog Habrahabr (http://habrahabr.ru/post/205290/) The algorithm is based on ideas explained by Huang and Langston in their paper "Fast Stable Merging and Sorting in Constant Extra Space (1989-1992" (http://comjnl.oxfordjournals.org/content/35/6/643.full.pdf) Since the implementation from (https://github.com/Mrrl/GrailSort) is macro-based, does not support non-memcopyable types and has a MIT license (which seems to be problematic for Boost), I implemented the algorithm from scratch following the article and taking ideas from Andrey's implementation. I added some new ideas and optimizations in order to reduce comparisons and elements moves. I must say that the implementation was really hard for someone like me without experience in sorting algorithms, the complexity is huge when compared with a classic mergesort algorithm. The implementation is already in develop and master branches but the develop branch contains more tests and a refactored and more documented code. So please check the code from the develop branch if interested. The implementation is still experimental and not production ready. What about benchmarks? I've only experimented in the oldest Visual compilers to make sure it correctly supports Boost.Move emulation and complexity guarantees were correct. Note that the STL algorithms tested in the benchmark might not be as fast as current implementations. In general, the new algorithms need much more elements moves than algorithms that allocate O(n) memory, but they are still quite fast when data movement is cheap (e.g. when a move constructor just copies a couple of pointers). These are the numbers for A VERY LIGHTWEIGHT object (a struct holding two integers, one for the key, another one to test the stability, don't take times very seriously, just pay attention to the number of comparisons/moves). ////////////////////////// ////////////////////////// STABLE MERGING ////////////////////////// ////////////////////////// - N: number of elements - NK: number of keys (0 means all keys different) - InplaceMerge: std::inplace_merge - Sqrt2AdaptMerge: adaptive_merge with an auxiliary buffer of 2*sqrt(N) elements - SqrtAdaptMerge: adaptive_merge with an auxiliary buffer of sqrt(N) elements - AdaptMerge: adaptive_merge with no external buffer - Cmp: number of comparisons / N - Cpy: number of move constructor/assignments / N - (ratio): time of execution / time needed by InplaceMerge ---------------------------------------------- Numbers produced by the bench_merge.cpp test in Boost.Move: ---------------------------------------------- - - N: 100001, NK: 511 - - InplaceMerge Cmp: 0.9989 Cpy: 1.5000 633.65us ( 1.00) Sqrt2AdaptMerge Cmp: 1.2429 Cpy: 4.4209 910.16us ( 1.44) SqrtAdaptMerge Cmp: 4.2708 Cpy: 5.6712 1.63ms ( 2.57) AdaptMerge Cmp: 5.6014 Cpy: 8.7573 3.11ms ( 4.91) - - N: 100001, NK: 2047 - - InplaceMerge Cmp: 0.9998 Cpy: 1.5000 604.77us ( 1.00) Sqrt2AdaptMerge Cmp: 1.2449 Cpy: 4.4483 934.83us ( 1.55) SqrtAdaptMerge Cmp: 2.0131 Cpy: 4.7609 1.12ms ( 1.85) AdaptMerge Cmp: 2.7608 Cpy: 11.1419 2.83ms ( 4.67) - - N: 100001, NK: 8191 - - InplaceMerge Cmp: 0.9999 Cpy: 1.5000 653.51us ( 1.00) Sqrt2AdaptMerge Cmp: 1.2443 Cpy: 4.3179 943.86us ( 1.44) SqrtAdaptMerge Cmp: 1.4661 Cpy: 4.4348 998.62us ( 1.53) AdaptMerge Cmp: 1.7692 Cpy: 10.6292 2.54ms ( 3.89) - - N: 100001, NK: 32767 - - InplaceMerge Cmp: 1.0000 Cpy: 1.5000 772.06us ( 1.00) Sqrt2AdaptMerge Cmp: 1.2417 Cpy: 4.4317 1.03ms ( 1.33) SqrtAdaptMerge Cmp: 1.3320 Cpy: 4.4758 1.06ms ( 1.38) AdaptMerge Cmp: 1.5295 Cpy: 10.1233 2.44ms ( 3.16) - - N: 100001, NK: 0 - - InplaceMerge Cmp: 1.0000 Cpy: 1.5000 881.88us ( 1.00) Sqrt2AdaptMerge Cmp: 1.2387 Cpy: 4.4124 1.16ms ( 1.31) SqrtAdaptMerge Cmp: 1.2933 Cpy: 4.4412 1.20ms ( 1.36) AdaptMerge Cmp: 1.4110 Cpy: 7.5794 1.93ms ( 2.19) In general, with no memory and enough keys, the algorithm needs 7,5*N data moves and 1,5*N comparisons. Data locality is quite high and with cheap-moving types the overall time can be just two-three times slower. With fewer keys, the algorithm might need upt to 5xN comparisons and 11xN moves. Number are improved if an auxiliary buffer of sqrt(N) elements is available. The number of comparisons and moves are even better than those shown in experimental results from several papers, but I still find them quite high. The algorithm needs some initial steps (e.g. unique key extraction) that are not amortized during the merge (adaptive_sort amortizes the initial steps much better ). I've derived the merge algorithm from the sorting algorithm so maybe there is room for improvement (I've invested much more time in the sorting algorithm). ////////////////////////// ////////////////////////// STABLE SORTING ////////////////////////// ////////////////////////// Numbers when sorting: - N: number of elements - NK: number of keys (0 means all keys different) - MergeSort: A half-copying mergesort (it only needs N/2 auxiliary memory) implemented in boost/move/algo/detail/merge_sort.hpp. Based on the paper "Fast mergesort implementation based on half-copying merge algorithm" by Cezary Juszczak (http://kicia.ift.uni.wroc.pl/algorytmy/mergesortpaper.pdf) Usually faster than std implementations with less auxiliary memory. - StableSort: std::stable_sort - HeapSort: std::heap_sort - QuartAdaptSort: adaptive_sort with N/4 auxiliary memory - Sqrt2AdaptSort: adaptive_sort with 2*sqrt(N) auxiliary memory - SqrtAdaptSort: adaptive_sort with sqrt(N) auxiliary memory - SqrtHAdaptSor: adaptive_sort with sqrt(N)/2 auxiliary memory - AdaptSort: adaptive_sort with no auxiliary memory - Cmp: number of comparisons / N - Cpy: number of move constructor/assignments / N - (ratio): time of execution / time needed by MergeSort [numbers produced by the bench_sort.cpp test in Boost.Move] - - N: 100001, NK: 511 - - MergeSort Cmp: 16.379 Cpy: 16.707 6.49ms ( 1.00) StableSort Cmp: 20.594 Cpy: 22.978 10.85ms ( 1.67) HeapSort Cmp: 16.992 Cpy: 22.098 10.98ms ( 1.69) QuartAdaptSort Cmp: 17.659 Cpy: 26.314 8.34ms ( 1.29) Sqrt2AdaptSort Cmp: 17.829 Cpy: 35.340 9.90ms ( 1.53) SqrtAdaptSort Cmp: 27.805 Cpy: 56.059 19.48ms ( 3.00) SqrtHAdaptSort Cmp: 27.356 Cpy: 60.375 20.35ms ( 3.14) AdaptSort Cmp: 27.352 Cpy: 67.889 21.83ms ( 3.36) - - N: 100001, NK: 8191 - - MergeSort Cmp: 16.394 Cpy: 16.725 7.47ms ( 1.00) StableSort Cmp: 20.578 Cpy: 22.978 11.92ms ( 1.60) HeapSort Cmp: 16.992 Cpy: 22.099 11.91ms ( 1.59) QuartAdaptSort Cmp: 17.676 Cpy: 26.362 9.26ms ( 1.24) Sqrt2AdaptSort Cmp: 17.847 Cpy: 35.747 10.93ms ( 1.46) SqrtAdaptSort Cmp: 18.977 Cpy: 41.641 12.19ms ( 1.63) SqrtHAdaptSort Cmp: 17.076 Cpy: 57.799 15.47ms ( 2.07) AdaptSort Cmp: 17.090 Cpy: 67.179 17.37ms ( 2.33) - - N: 100001, NK: 32767 - - MergeSort Cmp: 16.395 Cpy: 16.727 7.66ms ( 1.00) StableSort Cmp: 20.581 Cpy: 22.986 12.16ms ( 1.59) HeapSort Cmp: 16.994 Cpy: 22.099 11.96ms ( 1.56) QuartAdaptSort Cmp: 17.674 Cpy: 26.319 9.47ms ( 1.24) Sqrt2AdaptSort Cmp: 17.833 Cpy: 35.792 11.16ms ( 1.46) SqrtAdaptSort Cmp: 18.967 Cpy: 41.604 12.42ms ( 1.62) SqrtHAdaptSort Cmp: 17.065 Cpy: 57.756 15.71ms ( 2.05) AdaptSort Cmp: 17.081 Cpy: 67.131 18.32ms ( 2.39) - - N: 100001, NK: 0 - - MergeSort Cmp: 16.399 Cpy: 16.731 7.76ms ( 1.00) StableSort Cmp: 20.521 Cpy: 22.920 12.23ms ( 1.58) HeapSort Cmp: 16.991 Cpy: 22.094 11.85ms ( 1.53) QuartAdaptSort Cmp: 17.671 Cpy: 26.380 9.50ms ( 1.22) Sqrt2AdaptSort Cmp: 17.825 Cpy: 35.653 11.17ms ( 1.44) SqrtAdaptSort Cmp: 18.954 Cpy: 41.545 12.42ms ( 1.60) SqrtHAdaptSort Cmp: 17.058 Cpy: 57.694 15.66ms ( 2.02) AdaptSort Cmp: 17.072 Cpy: 67.072 17.57ms ( 2.26) In general, with no memory and enough keys, the algorithm needs nearly optimal comparisons and significantly more (4x) data movements. Data locality is quite high and with cheap-moving types the overall time can be just two-three times slower. With fewer keys, the algorithm performs worse but it's quite competitive. When extra memory (e.g. sqrt(N)) is available, the algorithm is quite fast with cheap-moving types. //////////////////////////////////////////// Final words: The effort to implement the algorithms was big and I couldn't fix many open bugs in my libraries, so in the following months I don't expect to invest much time on this. At least I wanted to publicly share the committed implementation so that it can be improved by sorting experts. I don't claim these algorithms are groundbreaking or even useful for many programmers, but they might be a good starting point. I'm not happy with the implementation as the algorithm is complicated and I' haven't found a way to simplify it further without noticeable slowdowns. For those interested in the implementation and the algorithm: please contribute correct benchmarks and testing, as there are very few open source implementations of similar algorithms. Any optimization, patch or bug report is welcome. Best, Ion

4 9

Boost 1.61.0 Beta 1 Release Candidate 2
by Vladimir Prus 26 Mar '16

26 Mar '16

Second set of release candidates for 1.61.0 beta 1 are now available: http://boost.cowic.de/rc/boost_1_61_0_b1_rc2.zip http://boost.cowic.de/rc/boost_1_61_0_b1_rc2.tar.bz2 http://boost.cowic.de/rc/boost_1_61_0_b1_rc2.tar.gz http://boost.cowic.de/rc/boost_1_61_0_b1_rc2.7z As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. The changes from RC1 are: * Top-level directory in the archive matches the name * Zip and 7z archives use CRLF line endings The known issues are: * Documentation build has some wrong-location, extra-files and broken-links issues. * There was a report of Boost.Context issue on OSX Release managers believe these issues are not blocking beta 1. The SHA1 checksums are as follows: 4d3c83d3a802d3dd12d4f2d516b3fcf076f6f6ba boost_1_61_0_b1_rc2.7z 8c6ac7326a3cabcabf6c7876052b73e0d41fc36d boost_1_61_0_b1_rc2.tar.bz2 e82b8ff7c3ad5b08c7dbeac1ea85fcf707a1cd4d boost_1_61_0_b1_rc2.tar.gz 7292e8fdac0566fe098a60a197a5722d381842d3 boost_1_61_0_b1_rc2.zip The SHA256 checksums are as follows: bc8341bfb8c6621319ad9eb732179fc7ec4da35c3cefc31b613f83ec3df10361 boost_1_61_0_b1_rc2.7z c0f06c78c195af9079773a2b250674244f1899ec81e84d5455f0761f1d888a16 boost_1_61_0_b1_rc2.tar.bz2 400fa0949aa201d993bf116461365e5d44904a3f8db6412f4f40f2b4ab490405 boost_1_61_0_b1_rc2.tar.gz d75688ecad601303dda2658e9a3d06f406dd4dc8e2c13c36bdadcac0a11dcffa boost_1_61_0_b1_rc2.zip Thanks! -- The release managers

9 15

[Root Pointer] Partial documentation
by Phil Bouchard 26 Mar '16

26 Mar '16

The documentation is not completed yet but an updated overview, a basic tutorial and the rationale are available here: https://htmlpreview.github.io/?https://raw.githubusercontent.com/philippeb8… https://htmlpreview.github.io/?https://raw.githubusercontent.com/philippeb8… https://htmlpreview.github.io/?https://raw.githubusercontent.com/philippeb8… Thanks, -Phil

1 0

[Root Pointer] Ultimate test - Neural Network
by Phil Bouchard 25 Mar '16

25 Mar '16

Hi, I wrote a small utility that reads PDFs over the Internet and converts the text into a tree of regular expressions. The goal here is to test root_ptr<> and see if it will stand up to this complexity. The code is very simple for the moment as you can see: https://github.com/philippeb8/root_ptr/blob/master/example/t100_test1.cpp Because it makes use of Bash utilities. I am also using libpstreams and "indent_facet.hpp". So anyway apparently it works fine and please let me know if you do not think the code is clean enough. Regards, -Phil

3 14

Boost libraries cannot yet be trusted
by Michael Witten 23 Mar '16

23 Mar '16

In short, I request that the maintainers start publishing cryptographically signed, strong hashes of: * downloadable files. * git objects (tags, and even commits). A cryptographic signature should probably be a personal signature of a relevant maintainer (rather than some generic project-level signature for which nobody has a sufficiently strong incentive to maintain the trustworthiness). Perhaps, each repository should include a collection of relevant public keys, so as to compound trustworthiness and ease dissemination. ------------------------------------------------------------------------ I'm new to this community, so forgive my ignorance if I've missed an existing solution. With each release, there should be included conspicuously (and widely) published means by which to check the authenticity of the relevant content. As far as I can tell, this is not yet the case. At the very least, within an email that announces a release, there should be a list of suitably safe (e.g., SHA-256) hashes for the downloadable files in question, including the hash of the relevant git commit object[s]. Now, SourceForge does indeed list SHA-1 and MD5 hashes of each file it offers for download, but they are not conspicuous; the user must know to click on an `i' symbol that sits next to each link (the `i' presumably stands for `information', but I wouldn't be surprised if it actually stood for `ignore me'). To make matters worse, that very icon and its associated functionality is only available when JavaScript is enabled, which is absurd. Furthermore, it's important that this list of hashes appear in as many independent places as possible, so that it becomes increasingly difficult to alter the association; for instance, if Gmane picks up an announcement email that includes such hashes, then an attacker will also have to compromise Gmane's servers in order to forge a new record of the intended payload. That is, widely published integrity information strongly suggests a [reasonable] means by which to calculate authenticity; certainly, the converse is true: Authenticity implies integrity. Of course, it's irritating (and unlikely) for a user to take the time to check multiple publishers for such integrity information every time a new release is made. Thus, it makes more sense to abstract away this process into a one-time dissemination of integrity information with which a user may determine the authenticity of other, related data that is provided by any publisher. Such an abstraction is provided by cryptographic signatures. By widely publishing a public key, a maintainer provides a [reasonable] means by which a user may calculate the authenticity (and thus also the integrity) of any other data that is signed by the associated private key. Now, that calculation is only as trustworthy as the private key itself, so it's important that there be a strong incentive to keep that private key trustworthy; this possibly implies that the private key in question should be intimately associated with the individual who uses it; this suggests that, as a matter of explicit policy, there should not be some generic project-level private key shared by multiple individuals across space or time. The easiest solution is to require that some *individual* maintainer of data be responsible for signing that data with his own personal signature. Of course, not every user has the machinery or desire to work with cryptographic signatures; some people are satisifed with merely checking that the hash of data matches the result provided by a trusted publisher. Fortunately, all parties can be satisfied simultaneously and cheaply: Provide the list of hashes as a cryptographically signed message. Furthermore, the source-control management tool `git' (which this project already uses) provides support for integrating cryptographic signatures; not only can a tag object be cryptographically signed, but every commit object can also be cryptographically signed. It's probably enough just to sign tags (those of releases, at the very least), but perhaps it would be worthwhile to sign a commit object that sits some sufficient number of commits ahead of the object last signed, so as to give users a kind of checkpoint of authenticity. It might be worthwhile to include in every repository the public key of each relevant maintainer (say, one file for each maintainer); this kind of publication would allow for compounding a key's trustworthiness with each new commit, and it would make dissemination of that information both easier and more specialized to its purpose. In any case, something must be done; this project sits at the core of much critical software, and its integrity should be ensured with greater zeal. Sincerely, Michael Witten

10 18

[Fit] formal review ends 20th March.
by Vicente J. Botet Escriba 23 Mar '16

23 Mar '16

Hi, There have been some that would be able to write a review next week-end. Others said that they had not enough time. Maybe having an additional week can help. I have not received confirmation from the review withards, but as there is no planned reviews for this week, I propose to continue with the review until 20th. Please take the time to do a review and share your point of view. Best, Vicente Fit is a header-only C++11/C++14 library that provides utilities for functions and function objects. Fit is: - Modern: Fit takes advantages of modern C++11/C++14 features. It support both `constexpr` initialization and `constexpr` evaluation of functions. It takes advantage of type deduction, varidiac templates, and perfect forwarding to provide a simple and modern interface. - Relevant: Fit provides utilities for functions and does not try to implement a functional language in C++. As such, Fit solves many problems relevant to C++ programmers, including initialization of function objects and lambdas, overloading with ordering, improved return type deduction, and much more. - Lightweight: Fit builds simple lightweight abstraction on top of function objects. It does not require subscribing to an entire framework. Just use the parts you need. Fit is divided into three components: * Function Adaptors and Decorators: These enhance functions with additional capability. * Functions: These return functions that achieve a specific purpose. * Utilities: These are general utilities that are useful when defining or using functions Fit has been tested on gcc 4.6-4.9, clang 3.4-3.7, and Visual Studio 2015. For more information see: Github:https://github.com/pfultz2/Fit/tree/boost Documentation:http://pfultz2.github.io/Fit/doc/html/ We encourage your participation in this review. At a minimum, kindly state: - Whether you believe the library should be accepted into Boost * Conditions for acceptance - Your name - Your knowledge of the problem domain. You are strongly encouraged to also provide additional information: - What is your evaluation of the library's: * Design * Implementation * Documentation * Tests * Usefulness - Did you attempt to use the library? If so: * Which compiler(s) * What was the experience? Any problems? - How much effort did you put into your evaluation of the review? More information about the review process can be found here:http://www.boost.org/community/reviews.html

8 16

[http] Design ideas for a request router
by Vinícius dos Santos Oliveira 23 Mar '16

23 Mar '16

Hi list, I've been designing a HTTP library for Boost inclusion for the last two years. First it was funded as a GSoC 2014 project. Then I continued to polish the implemented bits on my own and the library was peer reviewed (and rejected) last year. I'm currently addressing the requests made during last year's review and one of the requested items was a higher-level interface built on top the current building blocks that would be easier to use. One of such abstractions would be an HTTP request router. I usually do my research and check what others have done (not only in C++), read a lot of spec and do a design on my own (sometimes I ask for feedback of a few chosen ones). I rarely ask for public feedback because I usually can solve the interface issues on my own. However, Boost.Http is a new thing and I'm exploring an unexplored ground. I've been facing an issue for the last months and I'd like to have "open" feedback of anyone interested in this topic. Maybe it'll speed me up. The issue I'm facing is that (1) I haven't found enough diversity of HTTP request routers and (2) Boost.Http is a new thing and problems must be approached differently (what other HTTP library will let you do HTTP over uTP using Boost.Asio threading/async model?). Detailing the problem a little more: I categorize current HTTP request routers into two styles. The "tree style" is the style where you declare some paths to be handled and each request will be routed to at most one handler. You'll find this style usually when the author advertise a ReST support library (e.g.crow[1]). The "chained style" is the style where you declare a chain of <rule,handler> pairs (or anything in these lines) and one handler can "give up" and pass the route to the next in line. Rules in the "chained side" can overlap and an order exists (and must be explicit). You can find this style being used frequently in the Node.JS frameworks (e.g. connectjs[2]). You could reimplement these NodeJS APIs in C++ keeping a lot of the same look'n'feel. For instance, take a look at node.native[3]. I thought I could combine and allow both styles. Actually, Boost.Http don't force you to use any style and both could be used. However I wanted to implement both allowing some kind of interoperability and communication between them. There are a lot of open questions right now and I decided to implement both individually and only then come back trying to unify them. So, for now, my problem is designing the "chained style". Even implementing only "one style" I had open questions and I decided to draft an implementation to maybe give some light to my own mind. One thing that I was trying to address would be the "next" function. If you take a look at the connectjs library[2], you'll see that the "next" function is an argument passed to the handler and, if the handler wants to give up and pass the route to the next handler, it only needs to call "next". This behaviour could be emulated in C++ using std::function<>. An alternative design would be to make the handler return a bool. This is actually the design I've chose in Tufão[4] and I regret this decision to this date. The bad thing about this approach is the too-much-sync minded. If you need to communicate with a database to know whether you'll be able to handle the route then you need to block the whole thread under this approach. Knowing this is Boost and Boost is about serious C++ users I know I must be concerned about performance. Therefore, many may not like the std::function<> approach. It can imply some hidden allocation that you pay even if the handler is not going to give up on the route. Another approach would be to turn the handlers into template functors. However, this would be too much burden on the user. And if I chose this route, what would be the type of "next"? The approach I've chose was to encode the "next" function into the "request object". In Boost.Http, there is no "request object" like you'd be used to when using other APIs. Boost.Http exposes a socket and the socket will fill a message object of your choice (let's call it the input message) and later you pass it another message object to execute the reply (let's call it the output message). So the "next" function is really encoded in the input message. Other APIs use a passive style and constantly check if there is network activity and schedule new socket reads. Boost.Asio is more explicit and Boost.Http follows along. An active style is useful because it'll allow you to defer new operations to later when your server is under heavy load. Anyway, I felt that maybe I'll need a "done" function and I've added an empty one for now. I'll see if I'll really need it later when I integrate everything together. For now, just know that the "done" function does nothing. Anyway, this is my draft and I'd like to know your opinion: https://github.com/vinipsmaker/asiohttpserver/blob/router/example/router.cp… You can see that I'm declaring a static router because most of the time you don't change the rules at runtime. This router is actually more difficult to design and it'll be easier to add a "dynamic router" later on. I also want to mention that I'm aware of another effort by another developer (Uisleandro) trying to add a router to Boost.Http: https://github.com/uisleandro/Router_for_Boost.Http I also want to mention that performance of the implementation isn't really something I care about for the draft. If it were at another place it could mean that I'm not interested in implementation feedback. However it doesn't mean that I know the best way to implement these APIs and I'm still interested in implementation feedback (even more because I don't remember if I ever implemented much TMP before). Some points that I'll tackle LATER will be: - A router is a handler too, then you can have nested routers. - The router doesn't take the rule, only the handler. Later, I'll make algorithms that adapts rules and conditionally call your handler or pass the route to the next handler. This design is more flexible and I wish I could also use it in "tree style too". - How to create Message types more easily? I've read about component-based architectures before, but I never really understood them. Is there any library that was proposed to Boost in these lines that I could take a look at? [1] https://github.com/ipkn/crow [2] https://github.com/senchalabs/connect#mount-middleware [3] https://github.com/d5/node.native [4] http://vinipsmaker.github.io/tufao/ref/1.x/class_tufao_1_1_http_server_requ… -- Vinícius dos Santos Oliveira https://vinipsmaker.github.io/

7 20

Sean Parent to Keynote C++Now 2016
by Jon Kalb 22 Mar '16

22 Mar '16

Boost Developers, C++Now is announcing that the keynote speaker for our tenth conference will be the keynote that started us off, Sean Parent. http://cppnow.org/2016-conference/announcements/2016/03/22/keynote-announced .html Jon

2 1

[Fit] Formal review / Kris
by Krzysztof Jusiak 22 Mar '16

22 Mar '16

Hi, Firstly, sorry for submitting my review so late. > - Whether you believe the library should be accepted into Boost Yes. Although the submission is not perfect, I prefer boolean logic, and, therefore Fit a 1 for me. > - Your name Krzysztof Jusiak > - Your knowledge of the problem domain. I have been implementing similar solutions myself when experimenting with lambdas. I have also checked out functional part of Hana library. > You are strongly encouraged to also provide additional information: > - What is your evaluation of the library's: > * Design IMHO design is decent. Functionality is loosely coupled and really easy to follow. There are a few inconsistencies here and there but there were pointed out already and they don't have a huge impact on the overall solution. > * Implementation Quite a lot of macros but most of these are due to lack of language features or compilers bugs. Besides that, it looks alright. Moreover, I do agree with most issues pointed out already. > * Documentation Motivation could have been much better. Examples showing how much pain might be saved using Fit in comparison to writing the same things by hand would be great. Moreover, ready to copy examples would simplify testing the library. Personally, I would also add disassembled code for these examples showing how well-optimized code Fit can produce. Maybe, it's worth to add try-it-online functionality too? > * Tests Tests are short and easy to follow. I can't see coverage but it seems like most things are tested. Travis addition with each push make me confident that the library is always in a good shape. I would like to see performance tests though for both compilation times and run times. > * Usefulness IMHO Fit is defo a library to have in Boost for modern C++ development. I find the solutions provided by Fit very useful as I have been writing similar functionality myself. Nevertheless, documentation needs improving (as it was stated already) in order to state the purpose more clearly with clean examples. I have been worrying that there will be a clash with Hana. Having 2 modern libraries providing similar functionality would be confusing, however, my concerns were already clarified by Louis. > - Did you attempt to use the library? If so: > * Which compiler(s) Clang 3.7/3.8/HEAD, MSVC 2015 > * What was the experience? Any problems? No issues. > - How much effort did you put into your evaluation of the review? A few hours for the review, however, I have been looking and trying Fit for a while. Cheers, Kris

4 8

[test] Not using Boost.Test for an official Boost library
by Vinícius dos Santos Oliveira 22 Mar '16

22 Mar '16

Hi list, I'd like to know if it's mandatory to use Boost.Test if you intend to contribute a library to Boost. After facing an issue trying to enable compiler santizers on my tests[1] for long enough, I'd like to use a different test library. According to a survey done by Niall concerning new libs[2], everybody avoids Boost.Test, favouring assert/static_assert. I've been interested in using Catch[3], which is header-only and can be embedded, posing no problem to users (it'd be transparent). I've seen Boost.AFIO (which is not an official Boost library) already uses it. I've seen lightweight_test is also used within Boost[4]. If Boost.Test ever fix its integration problem with compiler sanitizers[1], I'd have no problem migrating everything back again to Boost.Test. However, it's more important for me to have this issue solved now so I can jump to the next task (valgrind and fuzz testing). I've also seen that some header-only libraries use a different build system for the test target[5] and using a header-only test library would be a lesser demand that should be okay. [1] https://svn.boost.org/trac/boost/ticket/11425 [2] https://raw.githubusercontent.com/boostcon/cppnow_presentations_2015/master… [3] https://github.com/philsquared/Catch [4] http://www.boost.org/doc/libs/1_60_0/libs/core/doc/html/core/lightweight_te… [5] https://github.com/boostorg/hana/blob/63c5f87dfdadd07e496cefefc63c3ea9968d3… -- Vinícius dos Santos Oliveira https://vinipsmaker.github.io/

6 5

Boost 1.61.0 Beta 1 Release Candidate 1
by Vladimir Prus 22 Mar '16

22 Mar '16

Release candidates for 1.61.0 beta 1 are now available: http://boost.cowic.de/rc/boost_1_61_0_b1_rc1.zip http://boost.cowic.de/rc/boost_1_61_0_b1_rc1.tar.bz2 http://boost.cowic.de/rc/boost_1_61_0_b1_rc1.tar.gz http://boost.cowic.de/rc/boost_1_61_0_b1_rc1.7z As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. These packages were generated by the CI system that Rene has put together, and one user-visible change is that the directory inside archive is named after git commit hash. This will be changed for the final release. Otherwise, these were smoke-tested on Windows and Linux, and should be functionally identical to usual packages. The SHA1 checksums are as follows: b8314cff39908e6d6221bdad01ce1f1468546419 boost_1_61_0_b1_rc1.zip cd916da1aa5ed812e538975171069506ecc4560c boost_1_61_0_b1_rc1.tar.bz2 ca18da298d739ef70145b29e3bd2c8d903067075 boost_1_61_0_b1_rc1.tar.gz 2fb4b8cf9112f59aa1c4b61f2ea0c66cbbe3ffd0 boost_1_61_0_b1_rc1.7z The SHA256 checksums are as follows: 3668b868d3f883327e2ff1324e09899cbb033087147d4dd268424a7729791f94 boost_1_61_0_b1_rc1.zip e07784e9770193ff1e68cfe05c6fd08ca05913afedaedf1aca33f6da30d49b17 boost_1_61_0_b1_rc1.tar.bz2 2344369b6859ed151589286d05b38764a902884c10a4dac9c67b133c6c046130 boost_1_61_0_b1_rc1.tar.gz 9ab80608c9ec70ec7afee25f2213f803ed3d15a71ade2c6ae184c48f33fd9d29 boost_1_61_0_b1_rc1.7z Thanks! -- The release managers

10 18

[Fit] formal review starts today
by Vicente J. Botet Escriba 21 Mar '16

21 Mar '16

Dear Boost community, sorry for the late anounce The formal review of Paul Fultz II's Fit library starts today, 2nd March and ends on 13th March. Fit is a header-only C++11/C++14 library that provides utilities for functions and function objects. Fit is: - Modern: Fit takes advantages of modern C++11/C++14 features. It support both `constexpr` initialization and `constexpr` evaluation of functions. It takes advantage of type deduction, varidiac templates, and perfect forwarding to provide a simple and modern interface. - Relevant: Fit provides utilities for functions and does not try to implement a functional language in C++. As such, Fit solves many problems relevant to C++ programmers, including initialization of function objects and lambdas, overloading with ordering, improved return type deduction, and much more. - Lightweight: Fit builds simple lightweight abstraction on top of function objects. It does not require subscribing to an entire framework. Just use the parts you need. Fit is divided into three components: * Function Adaptors and Decorators: These enhance functions with additional capability. * Functions: These return functions that achieve a specific purpose. * Utilities: These are general utilities that are useful when defining or using functions Fit has been tested on gcc 4.6-4.9, clang 3.4-3.7, and Visual Studio 2015. For more information see: Github:https://github.com/pfultz2/Fit/tree/boost Documentation:http://pfultz2.github.io/Fit/doc/html/ We encourage your participation in this review. At a minimum, kindly state: - Whether you believe the library should be accepted into Boost * Conditions for acceptance - Your name - Your knowledge of the problem domain. You are strongly encouraged to also provide additional information: - What is your evaluation of the library's: * Design * Implementation * Documentation * Tests * Usefulness - Did you attempt to use the library? If so: * Which compiler(s) * What was the experience? Any problems? - How much effort did you put into your evaluation of the review? More information about the review process can be found here:http://www.boost.org/community/reviews.html We await your feedback! Best regards, Vicente J. Botet Escriba

10 64

[Fit] formal review is over
by Vicente J. Botet Escriba 21 Mar '16

21 Mar '16

Hi, The review of the Fit library finished yesterday 20 March. Thanks to all the people who participated in the review, as a reviewer or commenting the threads. I hope to announce the result soon ;-) Best, Vicente P.S. Of course you/we can continue with the discussion and add issues in github that would help to improve the library. For more information see: Github:https://github.com/pfultz2/Fit/tree/boost Documentation:http://pfultz2.github.io/Fit/doc/html/

1 0

[fit] Mini Review (consider 1/2 or 1/4 weight)
by Artyom Beilis 21 Mar '16

21 Mar '16

Disclaimer: please consider my review as partial if at all because of the way I did it (see notes below) > - Whether you believe the library should be accepted into Boost No, I don't think so. I don't feel that library adds any real value to boost: being useful or in other words significantly simplifying rather straight forward tasks can't be done However I understand that there are some cases with template meta-programming that can make library useful shown there: http://article.gmane.org/gmane.comp.lib.boost.devel/265453 So I do think it another major review after significant redesign can be done. > - Your name Artyom Beilis > - Your knowledge of the problem domain. I worked a lot with lambda expressions and various callbacks also mostly in dynamic manner rather implementing functional programming. > - What is your evaluation of the library's: > * Design I did very brief analysis of design. What concerns me is wide use of static objects and declaration of "static functions". There is significant difference between static struct foo_class { void operator()() const;... } foo; and inline void foo() { } Of course two issues: 1. Inline functions are weak symbols and don't violate ODR 2. Static variables in C++ do violate ODR (btw in C they do not) so basically you COPY every instance of the functions across compilation unit. If you define some static function that does something by macro I'd rather expect to see stuff like inline void foo(...) { static foo_instance ... f = ...; f(...) } I don't know if it is implementable but it makes more scene or at least justify use of macro. On the other hand I don't see (with exception of some corner cases) why this is better than BOOST_FIT_STATIC_FUNCTION(foo) = fit:compose(bar1,bar2) // * calls bar1(bar2(...)) inline void foo(...) { bar1(bar2(...)) } or inlined auto foo = fit:compose(bar1,bar2); Is better than auto foo = [](...) { bar1(bar2(...) ) }; I understand (after getting this reply http://article.gmane.org/gmane.comp.lib.boost.devel/265453) That there are some meta-programming cases that the library is really helpful. But this isn't something I see in library documentation or it isn't the major library purpose. And for trivial cases I think direct approach is better as it is just clearer and easier to understand for an average code maintainer. > * Implementation Reviewed barely... no comment > * Documentation This is another major issue it does not clear what library does and how it is useful. This alone would make a condition on the acceptance. > * Tests Didn't reviewed > * Usefulness It is probably the major questions that the library need to ask. What is the purpose of the library and what problem it solves. I didn't find a complete answer to this question. > - Did you attempt to use the library? If so: No > - How much effort did you put into your evaluation of the review? Several hours - mostly reading docs and code. I can't say I reviewed most of the code or most of the docs. I stopped before as I couldn't find the satisfying answers regarding what library does. I understand that if somebody would submit the library regarding astrophysics or bio-modeling I'd had hard time to understand what library does. However regarding FIT I don't think it is the case. So if you (review manager/library designer) feel that I attempted to review a library in a field I don't get - feel free to ignore my review. Artyom Beilis

7 8

[release] New libraries documentation + release notes
by Daniel James 20 Mar '16

20 Mar '16

Hi, I'm starting to compile the release notes, so please add the info for your library. Easy way to do so is to click the pencil icon at the top right of the code at: https://github.com/boostorg/website/blob/master/feed/history/boost_1_61_0.q… Or you can just email me if you don't like quickbook. Also, the documentation for the new libraries in this release is now building okay and I've added links to the release notes, so please can the relevant people take a look: http://www.boost.org/users/history/version_1_61_0.html thanks, Daniel

3 4

[1.61] Two weeks remaining for new libraries and breaking changes
by Vladimir Prus 19 Mar '16

19 Mar '16

I wanted to remind that the master branch is closing for new libraries and breaking changes on Feb 24, about two weeks from now. We'll be closed for major changes on March 2. That's not a lot of time, please make sure any big work is completed. Thanks, -- Vladimir Prus http://vladimirprus.com

10 38

[Spirit X3] move_to
by Mikhail Strelnikov 18 Mar '16

18 Mar '16

Hi, I'm using Boost 1.60 with Spirit X3 from develop branch (because it has this fix <http://boost.2283326.n4.nabble.com/Single-element-attributes-in-X3-quot-sti…> ). If I change the rule from this: auto a2 = rule<class i2, ast::a2>{} = a1 >> a2_v2; to this: auto a2 = rule<class i2, ast::a2>{} = a1 >> '(' >> a2_v2 >> ')'; it stops compiling (both gcc and clang) with error "no matching function for call to 'move_to'". Here is full source code: #include <boost/spirit/home/x3.hpp> #include <boost/spirit/home/x3/support/ast/variant.hpp> #include <boost/fusion/include/define_struct_inline.hpp> #include <string> #include <vector> namespace ast { BOOST_FUSION_DEFINE_STRUCT_INLINE ( a1, (std::string, v) ) BOOST_FUSION_DEFINE_STRUCT_INLINE ( a2, (a1, v1) (std::vector<double>, v2) ) BOOST_FUSION_DEFINE_STRUCT_INLINE ( a3, (std::vector<a2>, v1) ) } using namespace boost::spirit::x3; auto a0 = rule<class i0, std::string>{} = lexeme[+alpha]; auto a1 = rule<class i1, ast::a1>{} = a0; auto a2_v2 = rule<class a2_v2, std::vector<double>>{} = -(double_ % ','); auto a2 = rule<class i2, ast::a2>{} = a1 >> '(' >> a2_v2 >> ')'; //auto a2 = rule<class i2, ast::a2>{} = a1 >> a2_v2; auto a3_v1 = rule<class a3_v1, std::vector<ast::a2>>{} = *(a2 >> ';'); auto a3 = rule<class i3, ast::a3>{} = a3_v1; using data = ast::a3; int main() { std::string script = ""; auto begin = script.begin(); auto end = script.end(); data v; bool ok = (boost::spirit::x3::phrase_parse(begin, end, a3, space, v) && begin == end); } Here is how it is compiled: #!/bin/bash wget --no-clobber http://netcologne.dl.sourceforge.net/project/boost/boost/1.60.0/boost_1_60_… tar -zxvf boost_1_60_0.tar.gz wget --no-clobber https://github.com/boostorg/spirit/archive/develop.zip unzip develop.zip mv ./boost_1_60_0/boost/spirit ./boost_1_60_0/boost/spirit_old g++ -std=c++14 test.cpp -I./spirit-develop/include/ -I./boost_1_60_0/ -o test

1 0

[Root Pointer] Benchmark
by Phil Bouchard 17 Mar '16

17 Mar '16

So I renamed block_ptr<> to root_ptr<> and the code is accessible from here: https://github.com/philippeb8/root_ptr I am sorry but I made a mistake in the benchmark again. root_ptr<> wasn't using the fast allocator. Now it does and the new benchmark is: unique_ptr (new): 42.3736 unique_ptr (make_unique): 59.6104 shared_ptr (new): 69.9175 shared_ptr (make_shared): 46.9994 shared_ptr (allocate_shared_noinit): 31.0648 root_ptr (new): 30.5549 Regards, -Phil

5 36

[ann][offtopic] GSoC with the STE||AR-Group
by Thomas Heller 17 Mar '16

17 Mar '16

Hi list, We are very sad that Boost didn't make it into GSoC this year. However, for students with enthusiasm for C++, Parallelism and Concurrency and looking for an interesting project for this summer, there are other opportunities. The STE||AR-Group (https://summerofcode.withgoogle.com/organizations/5183170693562368/) is looking for prospective students, we have a large variety of projects surrounding the HPX Parallel Runtime System (one of the reference implementations of the upcoming additions to the C++17 standard for parallelism and concurrency). You can find our project ideas list here: https://github.com/STEllAR-GROUP/hpx/wiki/GSoC-2016-Project-Ideas In addition, if you have a project idea you'd like to mentor that would fit into the scope of our organisation, we would be more than happy to welcome you! We are looking forward to your responses at hpx-users(a)stellar.cct.lsu.edu or on our IRC channel #ste||ar on Freenode! Best regards, Thomas -- Thomas Heller Friedrich-Alexander-Universität Erlangen-Nürnberg Department Informatik - Lehrstuhl Rechnerarchitektur Martensstr. 3 91058 Erlangen Tel.: 09131/85-27018 Fax: 09131/85-27912 Email: thomas.heller(a)cs.fau.de

1 0

[Fit] About supported C++ version
by Vicente J. Botet Escriba 16 Mar '16

16 Mar '16

Hi, I was wondering if Boost.Fit shouldn't be a library as Boost.Hana, a library that makes use of the last C++ version and avoids as much portability issues as possible. Which C++14 features will make the library simpler? Which adopted C++17 features will make the library simpler? Which other C++ features would be missing? Paul I guess that you are using a C++11 compiler and want to support this version, could you confirm? Best, Vicente

2 3

Providing means to verify integrity and authenticity for releases
by Daniel Hofmann 16 Mar '16

16 Mar '16

The current download page at > http://www.boost.org/users/download/ redirects the user to SourceForge for downloading sources and / or binary Boost distributions. SourceForge can no longer be trusted as a hosting platform, as you can for example see following this thread > http://lists.boost.org/boost-users/2016/02/85662.php where a user was tricked into downloading some arbitrary binary while downloading a Boost release. Unfortunately there does not seem to be a secure and convenient way to download Boost releases. Although Github's Boost "releases" can be found at > https://github.com/boostorg/boost/releases but those are only repository snapshots, from which you can not even build a Boost distribution. And whereas the Boost 1.60 rc1 announcement mail at least provides checksums > http://lists.boost.org/boost-users/2015/12/85435.php The official 1.60 release announcement mail does not > http://lists.boost.org/boost-users/2015/12/85467.php Correct me if I'm wrong, but there is no way for obtaining a Boost release and verifying its integrity and authenticity. The only option I'm seeing is recursively cloning all Boost repositories from Github and building a release by myself. Can we please change this situation? Here are some options that come to mind ordered by amount of effort: - Providing checksums - Educating users on the Downloads page - Signing releases with a trusted Release Team key - Changing the hosting platform Cheers, Daniel J H

7 8

[ann] C++ Archive Network
by Egor Pugin 16 Mar '16

16 Mar '16

Hi, I'd like to present my project - C++ Archive Network (or simply CPPAN). You can consider it as (yet another) C/C++ package manager. In the beginning it was targeting C++ Modules, but it seems it can handle many current C/C++ projects. You can read more information about idea and motivation from links below (see docs). This is an alpha release (0.1.2). I'm announcing it only here to get initial feedback (but still boost community is large enough). As always the general idea is to create programs faster, to reuse and share your or anyone's code. But specifically here: source only packages (no tools, no tests in distribution pkg - keep all your stuff in your repos), Modules-like paths (org.boost.algorithm), semantic versioning (semver.org) zero-conf. projects, all-or-nothing dependencies (no optional deps.) and some other convenient features. At the moment CPPAN works only with CMake. It generates files that you include to your project (see docs). To be closer to boost and modern C++ community I added some popular projects as demo versions: - boost 1.60.0 - all projects - some core parts work (filesystem, thread, log, asio etc.), did not tried less used libraries. - new boost libs: coroutine2 (added but not set up, so does not works), dll - boost incubator libs: fit, DI - you can try them faster during reviews - gsl, range-v3, mach7, sqlpp11 (and connectors) - some modern libs - concepts libs: cmcstl2, text_view - so users can try and adopt new C++ features faster - google's: gtest,gmock,protobuf, recent 'highwayhash' lib - sqlite3 (3.11.0) - zlib, bzip2 - libressl - image libs: libpng, tiff, gif, webp, some others - libpqxx Most of them just works. Almost all dependencies are met. In boost.* I do not untangle the core dependencies, so base dependency-ball is quite big. I believe that library authors can eliminate unneeded deps better. Links: https://cppan.org/ - website https://github.com/cppan/cppan - client, use issues for feedback https://github.com/cppan/cppan/wiki - docs https://github.com/cppan/demo_project - example project that uses cppan https://github.com/cppan/packages - example packages (config files) https://github.com/cppan/packages/blob/master/boost/boost.cppan - base boost config file (big list of deps, probably can be shorter) --- ps. I'm not writing about pros. and cons. Both are present. Just give CPPAN a try and we'll see how we can improve it. -- Egor Pugin

5 5

Re: [boost] [Block Pointer] Benchmarks
by Glen Fernandes 15 Mar '16

15 Mar '16

On Sun, Mar 13, 2016 at 1:02 PM, Phil Bouchard wrote: > Thanks for your help. > > So block_ptr<> wouldn't be a drop-in replacement for shared_ptr<> but an > add-on for: > - complex containers, > - neural networks, > - C# / Java / Javascript engines, > - etc. > No problem. Also renaming the thread to reflect the current benchmarks (since it doesn't appear that block_ptr is faster than shared_ptr where creation is involved). 1. Gathering these benchmarks is always useful, even if block_ptr was not designed to be a drop-in replacement for share_ptr. So you had the right idea, even if the execution needed some work. It's important to get the execution correct, though, otherwise the results are not meaningful - which is where I (and I believe Rob, also) was trying to steer you. 2. Looking at the numbers you obtained after modifying my benchmark example, they are close enough that at least you could say "Using block_ptr over shared_ptr won't be a significant performance loss": > unique_ptr (new): 47.7686 > unique_ptr (make_unique): 46.8545 > shared_ptr (new): 77.8261 > shared_ptr (make_shared): 50.8072 > shared_ptr (allocate_shared_noinit): 33.021 > block_ptr (new): 69.6554 3. There are more benchmarks beyond just creation (though creation is likely the most meaningfully expensive one). Copying overhead might be one: I haven't looked at what is involved in copying a block_ptr, but some work happens when you copy a shared_ptr. 4. shared_ptr by way of allocate_shared allows creation to not involve 'new' expressions, or even a call to '::operator new(std::size_t)' at all. i.e. For those C++ projects that have a requirement for all dynamic allocation in their project to involve some stateful custom allocator instances of some stateful custom allocator type, they can still use shared_ptr (with allocate_shared). Is this possible with block_ptr? I hope to take a look at the block_ptr motivation, design, and implementation when I have some time next week. The title of the thread caught my attention; "X is 600% faster than Y" always has a high excitement potential. Glen

8 16

[Block Pointer] Update
by Phil Bouchard 14 Mar '16

14 Mar '16

Hi, - So I've restructured all the code in the correct namespaces boost::smart_ptr & boost::smart_ptr::detail: https://github.com/philippeb8/block_ptr/tree/master/include/boost/smart_ptr - I am now using another smart pointer to refer to proxies because it is safer but the code is 15% slower than without it (now ~= shared_ptr<>): make: auto_ptr: 26211292 ns shared_ptr: 27291607 ns block_ptr: 61097868 ns new: auto_ptr: 23240569 ns shared_ptr: 48016207 ns block_ptr: 55554121 ns - Because of the removal of the proxy optimization there is a new caveat; if you assign an rvalue (temporary pointer on the stack) to a pointer on the heap (opposite of normal heap object assigned to stack pointer) then there the behavior will be undefined. I am looking to fix it or throw an exception but for now it's better not to use rvalues when assigning to pointer living on the heap as such: https://github.com/philippeb8/block_ptr/blob/master/example/t100_test1.cpp#… Regards, -Phil

2 13

[Fit] formal review ends today, 13th March.
by Vicente J. Botet Escriba 14 Mar '16

14 Mar '16

Hi, The formal review of Paul Fultz II's Fit library ends today, 13th March. If you had not time to do the review and you plan to do it, please let us know so that we see if the review can be extended. Up to now we had 3 formal review (2 for conditional acceptance and 1 against, not now). I have not done a review myself, but I have created a lot of issues on Github. Best regards, Vicente Fit is a header-only C++11/C++14 library that provides utilities for functions and function objects. Fit is: - Modern: Fit takes advantages of modern C++11/C++14 features. It support both `constexpr` initialization and `constexpr` evaluation of functions. It takes advantage of type deduction, varidiac templates, and perfect forwarding to provide a simple and modern interface. - Relevant: Fit provides utilities for functions and does not try to implement a functional language in C++. As such, Fit solves many problems relevant to C++ programmers, including initialization of function objects and lambdas, overloading with ordering, improved return type deduction, and much more. - Lightweight: Fit builds simple lightweight abstraction on top of function objects. It does not require subscribing to an entire framework. Just use the parts you need. Fit is divided into three components: * Function Adaptors and Decorators: These enhance functions with additional capability. * Functions: These return functions that achieve a specific purpose. * Utilities: These are general utilities that are useful when defining or using functions Fit has been tested on gcc 4.6-4.9, clang 3.4-3.7, and Visual Studio 2015. For more information see: Github:https://github.com/pfultz2/Fit/tree/boost Documentation:http://pfultz2.github.io/Fit/doc/html/ We encourage your participation in this review. At a minimum, kindly state: - Whether you believe the library should be accepted into Boost * Conditions for acceptance - Your name - Your knowledge of the problem domain. You are strongly encouraged to also provide additional information: - What is your evaluation of the library's: * Design * Implementation * Documentation * Tests * Usefulness - Did you attempt to use the library? If so: * Which compiler(s) * What was the experience? Any problems? - How much effort did you put into your evaluation of the review? More information about the review process can be found here:http://www.boost.org/community/reviews.html We await your feedback!

4 6

[Fit] Review
by Zach Laine 13 Mar '16

13 Mar '16

- Whether you believe the library should be accepted into Boost Yes, conditionally. * Conditions for acceptance I think the documentation and naming issues I raise below, and those filed on GitHub by me and others should be addressed before acceptance. Also, the ADL issues that Steven Watanabe alluded to previously need to be fixed. After that, I think it should be re-submitted. - Your name Zach Laine - Your knowledge of the problem domain. I do generic programming regularly, and have done for years. You are strongly encouraged to also provide additional information: - What is your evaluation of the library's: * Design I think it's good. I particularly like the fact that it attempts to keep everything constexpr- and SFINAE-friendly wherever possible. I *really* like reveal() and failure(). Too few TMP-heavy libraries pay attention to providing good error messages. I have no problem with the constness requirements on Callables used throughout Fit, as was discussed previously. I even consider this a feature, allowing me to detect non-const Callables, which are almost always an error on my part. This is especially true since std::ref() and mutable_() let me explicitly choose how to handle mutable Callables, in a way that is also explicit at the call site. There are a number of adaptors that I find have obscure names: by() is a projection; why not call it project()? compress() is defined in terms of "fold", with a link to the Wikipedia page for same; why not call it foldl()? Similarly, reverse_compress() should be foldr(). flow() is a super obscure name! Why is this not reverse_compose() or similar? indirect() could more easily be understood if it were called deref() or dereference(). I don't feel as strongly about partial(), but I think it might be clearer if it were called partial_apply() or curry(). conditional() should be called invoke_first(), call_first_of(), or similar. I find it too easy to confuse with if_(). * Implementation I only briefly looked at the implementation, and only a few adaptors at that. What I saw did not leave me any concerns in particular. However, I *am* concerned by Steven Watanabe's claim that the library is ADL-unsafe. He did not state exactly why that I could tell, but this needs to be addressed if so. * Documentation The Quick Start section is good at showing a compelling motivating case for using the library. The result at the end of the section looks like a very good start on a "Scrap Your Boilerplate" solution for simple, dump-style printing. It's relatively easy to read and write. The documentation is what needs the most work, from what I've seen. The Quick Start is quite nice, but then there are some things that are underexplained in the subsequent Overview and Basic Concepts sections. For instance, why are these macros used everywhere and what do they do? They should be used for the first time after showing what the expanded code looks like. This will justify their use for those users that want them, and show those that don't what they can write instead. Others have written during the review that they don't understand why this library is useful. I think this is simply a documentation failure. I find the printing example from the Quick Start compelling, but perhaps Paul could show how it would have to be done if hand-written (even if only partially). Also, Paul has told me offline that there are a small number of primitive operations on which everything else is built (pack, unpack, and apply, IIRC). Perhaps show how those can be used to implement the other adapters, and how hard they are to write yourself. Showing how at least some of the library can be used as fundamental building blocks would go a long way. Some specifics. I have read the online docs before, and I put several bugs into the GitHub page for what I consider insufficient examples or explanations. Some new points, though: I think alias() is in bad need of a motivating example. I don't understand the distinction between lazy() and protect() just from the descriptions. In particular, this is what protect()'s docs say: '' The protect function adaptor can be used to make a bind expression be treated as a normal function instead. Both bind and lazy eargerly evaluates nested bind expressions. The protect adaptor masks the type so bind or lazy no longer recognizes the function as bind expression and evaluates it. '' I don't know what "masks the type" means here. This really needs an example. * Tests I did not run the tests, and just sort of spot-checked them. They seem a bit thin. In particular, one of the ones I looked at was conditional(). This one seems like it is needs more coverage, including thorny ones that must be kept working when maintenance occurs. There are probably others adapters that need similar treatment. Also, consider this -- Steven pointed out this as a failure case: boost::fit::conditional(identity(), identity())(0); and Paul says that it is supposed to fail, and that this failure is a feature, not a bug. If so, a minimal use like this that fails to compile needs to be added as a fail-compile test (and of course this intention should be documented). * Usefulness I think the library is very useful. There seem to be some things in there that use of which might be deemed a bit clever (not the good kind), like infix(), but then there are things like conditional() that I can see being *extremely* useful. - Did you attempt to use the library? If so: Yes. * Which compiler(s) Clang 3.6 * What was the experience? Any problems? I found I could gin up quick uses of things like conditional() (the most interesting adaptor for my purposes) in a short period of time. It was quite straightforward. - How much effort did you put into your evaluation of the review? About 5 or 6 hours. Zach

9 23

Alternative names to Boost.Fit
by paul Fultz 13 Mar '16

13 Mar '16

Hello All, Boost.Fit is a function utility library, however, the name currently doesn't have anything with this. I originally chose the name because it started with F(for function) and it was short and sounded nice. However, there could be some names(or abbreviations) that more adequately describe the library. Here are some alternatives that are short: - Boost.FP - Boost.FPL - Boost.Fun - Boost.FN Of course, I prefer the Boost.FN name. Names like Boost.FP or Boost.FPL could imply that it provides full functional constructs whereas Boost.Fit does not and is mainly focused on functions. Either way, this is something reviewers could consider as they review the library as I am not strongly tied to the name Boost.Fit. Thanks, Paul

13 27

[Block Pointer] Up to 600% faster than Shared Pointer
by Phil Bouchard 13 Mar '16

13 Mar '16

- I made the proxy explicit. Now it can be used 3 different ways: 1) Clothesline style: block_proxy x; block_ptr<int> v = block_ptr<int>(x, new block<int>(11)); block_ptr<int> w = block_ptr<int>(x, new block<int>(12)); 2) Root style: proxy_ptr<char[9]> u = proxy_ptr<char[9]>(new block<char[9]>()); 3) Container style (very easy to write containers now): struct list : block_proxy { public: list() : root(*this) {} [...] private: block_ptr<node> root; }; - I removed the capacity to unify sets. Why? Because it's faster & cleaner without it. - If we use fastblock<>() then the speedup can go up to 600% compared to shared_ptr<>: new: auto_ptr: 23174753 ns shared_ptr: 49726615 ns block_ptr: 7812659 ns - Once again all the examples can be found here: https://github.com/philippeb8/block_ptr/tree/master/example - And the pointer itself here: https://github.com/philippeb8/block_ptr/blob/master/include/boost/smart_ptr… Regards, -Phil

3 18

32/64 library name conflict under Windows?
by Peter Dimov 12 Mar '16

12 Mar '16

I remember that we discussed this problem before: C:\Projects\boost-git\boost>b2 --with-system toolset=msvc-10.0 address-model=32,64 [...] error: Name clash for '<pstage\lib>libboost_system-vc100-mt-gd-1_61.lib' error: error: Tried to build the target twice, with property sets having error: these incompatible properties: error: error: - <address-model>32 error: - <address-model>64 error: error: Please make sure to have consistent requirements for these error: properties everywhere in your project, especially for install error: targets. but don't remember what we concluded. Will we support building both 32 and 64 bit libraries under Windows? At present if I want to have an IDE project that has both Win32 and x64 configurations I need to build the 32 bit libraries, move them out of stage/lib somewhere, then build the 64 bit libraries, then move them out of stage/lib to somewhere else, and set my library directories in the IDE accordingly. It would be much more convenient if 32/64 were encoded into the name, so that I can leave my library path to point at stage/lib and rely on autolink to choose the right .lib file automatically, like it works today for the other options (debug/release, static/dynamic runtime).

14 25

[Fit] Louis Dionne's formal review
by Louis Dionne 12 Mar '16

12 Mar '16

First of all, sorry for submitting my review so late. > - Whether you believe the library should be accepted into Boost Yes, conditionally. > - Your name Louis Dionne > - Your knowledge of the problem domain. Extensive. In fact, I have implemented something very similar to Fit in parallel to Paul, but in the Hana library. Hence, I understand what Fit can be useful for, and I know many of the challenges Paul must have faced in designing the library. > You are strongly encouraged to also provide additional information: > - What is your evaluation of the library's: > * Design Good. It is simple and quite lean, which is nice. However, - The issue about `capture`'s semantics (and `pack`'s semantics too) ought to be addressed. I created an issue for this: https://github.com/pfultz2/Fit/issues/141. - It would be nice to provide a master header: https://github.com/pfultz2/Fit/issues/143 - I am not sure that `alias` has its place as part of the public interface of the library. I have only looked at it quickly, but it seems to diverge pretty heavily from the purpose of the rest of the library. I know it's used to implement `fit::pack`, but is it necessary to make it part of the public interface? Zach Laine already opened a similar issue here: https://github.com/pfultz2/Fit/issues/95 - I'm not sure about `compress` and `reverse_compress`. I think `fold` and `reverse_fold` (or my favorite `fold_left` and `fold_right`) would be better suited. An issue was already filed by Vicente here: https://github.com/pfultz2/Fit/issues/62 > * Implementation I have not looked at the implementation intensively, but I have to say that the profusion of macros is a bit off-putting. That being said, it's probably difficult to do better while supporting archaic compilers such as GCC 4.6. Hats off to Paul on this one. Also, I think the `fit/detail/ref_tuple.hpp` is unused and should be removed. Finally, why do you use your own `move` function? Is it because it is not marked constexpr in pre-C++14? > * Documentation I submitted pull requests to fix typos, but these are not worth mentioning here. Comments that might be of interest for the purpose of this review were made in the form of GitHub issues: - https://github.com/pfultz2/Fit/issues/131 - https://github.com/pfultz2/Fit/issues/132 - https://github.com/pfultz2/Fit/issues/133 - https://github.com/pfultz2/Fit/issues/135 - https://github.com/pfultz2/Fit/issues/136 - https://github.com/pfultz2/Fit/issues/138 - https://github.com/pfultz2/Fit/issues/139 - https://github.com/pfultz2/Fit/issues/140 - https://github.com/pfultz2/Fit/issues/142 - https://github.com/pfultz2/Fit/issues/144 > * Tests I have looked quickly, and basically all the individual components seem to be tested. It's hard to evaluate the depth in which each component is tested, but it seems OK. Also, the fact that the library is tested on Travis CI on each commit is a blessing, and it makes me much more confident about its quality. > * Usefulness This, I think, is the biggest problem of the library. I personally know very well why the library is useful, but I can also understand that someone with a different background would not feel the same. In my view, the library is mostly useful as a replacement to shortcomings of lambdas in C++11/14. Not only this, but in large part yes. Indeed, let's say I have a function object `f`, and I'd like to get a function object that swaps the arguments and calls `f`. The obvious solution (simplified) is auto g = [f](auto x, auto y) { return f(y, x); }; In other words, the simplest way to express my intent is to use a lambda and to do exactly what I mean. Unfortunately, this has several limitations - The lambda above can't be constexpr - The lambda can't appear in an unevaluated context So I end up using `fit::flip`. In a different situation, I might want to capture many variables in a lambda, but moving them into the capture (not copying). So I write auto f = [x = std::move(x)...](auto const& param) { ... }; but unfortunately there's no way to capture a parameter pack by moving each of its elements in a lambda. So I resort to using `fit::capture`. Examples like this abound, and IMO these limitations are the main (but not the only) reason for using Fit. Actually, this is how I implemented a library similar to Fit inside Hana; I started by using lambdas everywhere and then I wanted to make everything constexpr, capturing by move and things like that. All of this is very useful, but I feel like the documentation completely misses the goal of explaining the problem solved by Fit (the problem I would use it for, at least). This failure of motivating its own existence is the main reason why I think Fit should be accepted conditionally. > - Did you attempt to use the library? If so: > * Which compiler(s) AppleClang 6.1.0.6020053 (shipped with Xcode 6.4) Clang 3.5, 3.6, 3.7 I used both the Makefile and the Ninja generators for CMake, and both worked. > * What was the experience? Any problems? Classic CMake setup, everything works well and the tests compile and run fast. No problem whatsoever, as expected. > - How much effort did you put into your evaluation of the review? A couple of hours for the formal review itself, but I have been looking at Fit's development for a while. Summary ------- Fit should be accepted conditionally and re-submitted for a mini-review before it can be accepted. My conditions are 1. Correctly justify the purpose of the library 2. Resolve the issues on `capture` and `pack`'s semantics I think all the other points I raised are important too, but they shouldn't refrain Fit from being accepted. I also trust that Paul would be willing to continue working on the issues that were raised during this review if Fit were to be accepted. Regards, Louis

4 5

Boost.ASIO SSL examples
by Umit Sami 11 Mar '16

11 Mar '16

Hi All, SSL examples in boost.asio is very limited and not that clear. How can I improve my knowledge of this great network/security library ? what are some of well known online websites and books I can read/buy to better write secure/encrypted client-server applications ? Thank you, U

2 1

[release] Need help to test new release archives.
by Rene Rivera 09 Mar '16

09 Mar '16

As part of my attempt to make the Boost release management less painful, for everyone, I've implemented building of the release archives in Travis-CI. As of yesterday archives of the "boost" super-project master branch are getting uploaded to the bintray.com service at < https://bintray.com/boostorg/snapshots/master/view>. There are still some kinks in how this works but it's automated enough at this point that it might serve the upcoming release needs. I would appreciate it if people download the archives available at the above link and test them out. In particular I'm looking to see if there's anything missing or generally incorrect. For reference the archives are named with the commit SHA that they correspond to. Thank you. -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

6 16

Re: [boost] [Boost-users] [Fit] formal review starts today
by paul Fultz 09 Mar '16

09 Mar '16

>> >> >> >> Quick Start:Function Objects >> >> >> >> "We can make it behave like a regular function if we > construct >> the class >> >> as a global variable." >> >> >> >> What about a non-global >> >> >> >> sum_f sum = sum_f(); >> >> >> >> makes 'sum' not behave like a regular function other > than the >> fact that >> >> the variable 'sum' may eventually go out of scope ? >> >> >> > >> > In C++, a regular function is always global, there is no such >> thing as local >> > function(sans gcc extensions). >> >> My point is that the non-global 'sum' in my example above > behaves just >> as much like a regular function as your global 'sum'. You may > want to >> promote the idea of global function objects but I think that this is >> personally a bad idea. IMO global variables of any kind are to be >> avoided. >> >> It is quite common in several modern C++ libraries to declare functions as >> global objects. There are many advantages to this. Why do you believe it >> should be avoided? Especially since it has the same effect as a free >> function. >> DO you believe free function should be avoided as well? > > Global objects, whether functions or data, increases the chances for > name clashes. Also accessing global data increases the chances for > errors in a multi-threaded environment. > > Free functions can be in a namespace, as the standard library functions > are in the 'std' namespace. This helps greatly in avoiding name > conflicts. By global variables, I mean defined at the namespace level, not solely at the global namespace level. So functions using BOOST_FIT_STATIC_FUNCTION can be defined within a namespace. Also, the function objects are `const` so there isn't an issue from multithreaded environments. > >> >> >> >> > >> > >> >> >> >> Quick Start:Lambdas >> >> >> >> Why do we need both BOOST_FIT_STATIC_LAMBDA and >> >> BOOST_FIT_STATIC_LAMBDA_FUNCTION ? I would seem that >> >> BOOST_FIT_STATIC_LAMBDA_FUNCTION would be adequate and >> >> BOOST_FIT_STATIC_LAMBDA is just redundant, mimicking lambda >> syntax to no >> >> purpose. >> >> >> > >> > BOOST_FIT_STATIC_LAMBDA_FUNCTION and BOOST_FIT_STATIC_FUNCTION >> both define a >> > function at global scope, and can only be used at global scope, >> whereas >> > BOOST_FIT_STATIC_LAMBDA can be used to constexpr initialize local >> variables >> > as >> > well. >> >> It might be good to add that when the end-user first encounters >> BOOST_FIT_STATIC_LAMBDA, because the name does not suggest >> initialization of local objects. Furthermore I cannot imagine why one >> would want to use it to initialize a local object, >> >> >> Really? You just said that you would prefer avoiding global functions. > > I mean that for local objects I do not see the reason why I would ever > use BOOST_FIT_STATIC_LAMBDA instead of initializing local objects in the > normal C++ way(s). If this is not the case you need to explain what > problem(s) BOOST_FIT_STATIC_LAMBDA solve in initializing local data > which ordinary C++ initialization of local data could encounter. If > there aren't any problems BOOST_FIT_STATIC_LAMBDA solves in initializing > local data I see no purpose for its existence. > Well, they can still be passed to constexpr functions, even if they are local, I probably shouldn't discuss BOOST_FIT_STATIC_LAMBDA in the Quick Start guide because its usage is not quite as a common. >> >> so you might want to >> explain the benefit of doing so as opposed to the normal syntax for >> creating a lambda function. >> >> >> Maybe the quick start guide isn't the place for this in the first > place. > > I would hope to convince you that a good Overview of your library should > come first and then all the Quick Start guides, tutorials, examples etc. > would make much more sense once your end-user understands what your > library really does in terms of at least the main general functionality. I usually start with the Quick Start guide with a library in order to get an understanding of what components are in the library and what they can do, then I start delving into the other components from there. Thats what I am showing in the Quick Start guide. I guess people have different ways of learning a library. I wonder what is needed to be explained better in a initial overview of the library. > >> >> >> > In fact, BOOST_FIT_LIFT uses this since it is not always clear > what >> > context the user might call BOOST_FIT_LIFT. >> > >> > >> >> >> >> Quick Start:Overloading >> >> >> >> The overloading adaptors show two or more lambda functions. > Can >> they >> >> also work with function objects ? Or a mix of lambda > functions and >> >> function objects ? In fact all the reamining Quick Start > topics >> show >> >> examples with lambda functions. Do they also work with > function >> objects ? >> >> >> > >> > Yes it can be used with function objects. I probably should show >> an example >> > of >> > that as well. I used the lambdas because of the terseness of > them. >> >> Evidently the adaptors can be used with any Callable. I think you >> should >> make that point very strongly and show that in examples also. >> >> >> Agreed. >> >> >> > >> > >> >> >> >> Quick Start:Variadic >> >> >> >> I do not understand what 'We can also make this print > function >> varidiac, >> >> so it prints every argument passed into it.' means ? >> >> >> > >> > I'll try to explain that better, but basically it will print > each >> argument, >> > so: >> > >> > print("hello", 5); // Will print "hello" and > 5 >> >> I wouldn't associate that with the word 'Variadic' but I do > think you >> need to explain that more clearly. >> >> >> I always understood variadic to mean taking a variable number of >> arguments. What do you understand variadic to mean? > > Your terminology is fine, but I always think of variadic in terms of > variadic templates or variadic macros. After all your not making the > print function variadic in the sense of taking a variable number of > arguments. Yes, I am, so I probably need to make that more clear in the documentation. > The simple_print functionality is any of 3 different lambda > functions, with 'conditional' picking the first one that is callable and > > 'fix' passing in the callable as the first parameter. So I really > don't > understand what 'by' does here in printing each argument irregardless of > > your 'Variadic' terminology. You need invoking examples and then show > what the output would be for each invocation, and then it would be > easier for me and others to understand what 'by' does in this situation. > Yep, that part needs to go into more in-depth. >> >> >> > >> > >> >> >> >> I do not think the Quick Start explains very much since it is >> dealing >> >> with adaptors of which we know almost nothing and the >> explanation for >> >> these adaptors and what they actually do is very terse. >> > >> > >> > Probably can expand the explanation of adaptors a little more. >> >> Good idea. What do adaptors create ? >> >> >> They create a function. >> >> Different function objects I would >> imagine ? In that case how about the explanation that adaptors take >> Callables as input and generate function object types that adapt the >> original functionality of one or more Callables to some other purpose. >> >> >> The examples are already show taking Callables. Are you suggesting I >> show an example taking a member function or something? > > Global/static function, member function, std::function, boost::function, > Boost Phoenix and/or Boost lambda function objects, instantiated > template functions. My point is that you should show your library > functionality working with as many types of Callables as possible. > Instead your doc suggests that function objects and lambda functions are > the only type which can be passed to your library's functionality and > you enforce this view by your examples. I'll try to do that. > >> >> > >> > >> >> >> >> In the 'Signatures' section of the Overview I read: >> >> >> >> "All the functions are global function objects except > where an >> explicit >> >> template parameter is required." I honestly don't > know what this is >> >> supposed to mean. Does this refer to when function objects > are >> referred >> >> to as parameters to the adaptors, functions, and utilities of >> the library >> >> ? >> >> >> > >> > I don't understand what you are asking. It means that the >> function is >> > written >> > like this in the documentation: >> > >> > template<class IntegralConstant> >> > constexpr auto if_(IntegralConstant); >> > >> > But its actually a function object like this in the code: >> > >> > struct if_f >> > { >> > template<class IntegralConstant> >> > constexpr auto operator()(IntegralConstant) const; >> > }; >> > const constexpr if_f if_ = {}; >> > >> > However, `if_c` is written like this in the documentation: >> > >> > template<bool B, class F> >> > constexpr auto if_c(F); >> > >> > It requires the bool `B` template parameter explicity. So in the >> code it is >> > written as a function and not as a function object. >> >> I don't understand to what you are referring when you say > 'function'. >> Are you talking about adaptors in your library, functions in your >> library, or what ? >> >> >> I am talking about all functions that are defined in the library, that >> includes adaptors as well. I am not sure how to make that clearer. >> >> Please try to understand that your use of the word >> 'function' is very broad but that the word 'function' > in C++ has a much >> narrower meaning. >> >> >> By function, I mean something like in the example: >> >> template<class IntegralConstant> >> constexpr auto if_(IntegralConstant); >> >> I think everyone agrees that is a function in C++. > > I call that a function template. Which is a family of functions. > My definition for 'function' is not the > > same as yours. I know you feel differently but please realize that the > term 'function', to mean any and every type of callable in C++, is not a > > universally agreed on terminology. I would bet that for the vast > majority of C++ programmers a function is: > > ReturnType FunctionName(ZeroOrMoreFunctionParameters); Yes, which can happen at class scope or namespace scope, and it can also be templated.

5 7

Re: [boost] 2 regression test failing at under 1.60 (John Maddock)
by Steven Kelso 09 Mar '16

09 Mar '16

On Tue, Mar 8, 2016 at 3:42 AM, <boost-request(a)lists.boost.org> wrote: > Date: Mon, 7 Mar 2016 19:21:26 +0000 > From: John Maddock <jz.maddock(a)googlemail.com> > To: boost(a)lists.boost.org > Subject: Re: [boost] 2 regression test failing at under 1.60 > Message-ID: <56DDD4B6.6030603(a)gmail.com> > Content-Type: text/plain; charset=windows-1252; format=flowed > > > > On 07/03/2016 17:04, Steven Kelso wrote: > > I've just started trying to install version 1.60 of boost using the gcc > > 5.3.0 compiler. With a vanilla download and no chnages it all seems to > > compile correctly, but I have a problem with 2 library regressions tests > > not terminating. They have both run for over 18 hours before I had to > kill > > them. I was using the options and configuration "out of the box" so > > optimization was -O3. > > I'm unable to reproduce on Ubuntu x64, all the Math lib tests pass fine > for me with gcc-5.3.0 in both C++03 and C++11 modes. > > So you'll need to debug and supply a patch if you're able, > > Thanks, John. > I'm trying to find out what exactly is causing the issue here. Would it be possible for you to show me the 'gcc -###' output so that I can compare to my version of gcc. Since the failure occurs only with optimization turned on i'm now leaning towards a compiler issue since I compiled gcc from source for this test. I'm hoping it's something obvious when I look closer. So far this has failed on a RHEL6.5 system running a locally compiler gcc 5.3.0 as well as a RHEL 7.2 based system compiled with the same gcc 5.3.0. Many thanks for your help, S

1 0

Re: [boost] [C++-sig] Trouble building boost with Visual Studio 2010
by Stefan Seefeld 09 Mar '16

09 Mar '16

Hi David, On 09.03.2016 05:04, David Aldrich wrote: > > Hi > > > > I am trying to build Boost 1.60 with Visual Studio 2010 Professional > on Windows 10. > > > > I use the command: > > > > b2 toolset=msvc-10.0 --with-python link=shared > > > > and get the following error: > > > > python34.lib(python34.dll) : fatal error LNK1112: module machine type > 'x64' conflicts with target machine type 'X86' > Just a quick guess: is it possible that your "libpython34.dll" file is a 64-bit binary, when the command really requires it to be a 32-bit binary ? > > > I guess this means I have a conflict of 32-bit and 64-bit libraries. > I want to target 32-bit (X86). > > > > Do I need to install a 32-bit version of Python? I wonder if that can > co-exist with the current version of Python? > I'm unfortunately unable to answer your question, as the question seems more about the build system than Boost.Python itself. Therefore I'm including the Boost mailing list in my reply, hoping that some Boost.Build expert may be able to help. Regards, Stefan > > > Best regards > > > > David > > > > > > _______________________________________________ > Cplusplus-sig mailing list > Cplusplus-sig(a)python.org > https://mail.python.org/mailman/listinfo/cplusplus-sig -- ...ich hab' noch einen Koffer in Berlin...

1 0

Re: [boost] [Boost-users] [Fit] formal review starts today
by paul Fultz 09 Mar '16

09 Mar '16

> On Tuesday, March 8, 2016 11:39 PM, Gavin Lambert <gavinl(a)compacsort.com> wrote: > > On 9/03/2016 10:43, paul Fultz wrote: >>> I would hope to convince you that a good Overview of your library > should >>> come first and then all the Quick Start guides, tutorials, examples > etc. >>> would make much more sense once your end-user understands what your >>> library really does in terms of at least the main general > functionality. >> >> I usually start with the Quick Start guide with a library in order to get > an >> understanding of what components are in the library and what they can do, > then >> I start delving into the other components from there. Thats what I am > showing >> in the Quick Start guide. >> >> I guess people have different ways of learning a library. I wonder what is >> needed to be explained better in a initial overview of the library. > > I suspect part of the problem is that the Introduction appears under the > ToC at the top level instead of on its own page above the Quick Start. > Thus someone not scrolling down is likely to miss the Introduction and > > start with the Quick Start. > > Still, even the Introduction is a little light on the things an Overview > generally needs to cover: "why should I consider using this library and > what types of problems does it solve?" (Sometimes some of this is split > to a separate Motivation section.) Yea, I think adding Motivation section will be helpful. > > Quick Starts / Tutorials are more for answering "now that I've already > decided to (probably) use this library, how do I do XXX?" > > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users >

2 1

Re: [boost] [Boost-users] [Fit] formal review - should we propose some parts to Boost.Config/Boost.Core
by paul Fultz 09 Mar '16

09 Mar '16

> On Tuesday, March 8, 2016 6:52 PM, Steven Watanabe <watanabesj(a)gmail.com> wrote: > > AMDG > > On 03/06/2016 09:39 PM, Paul Fultz II wrote: >> >> On Sunday, March 6, 2016 at 3:44:31 AM UTC-6, Vicente J. Botet Escriba >> wrote: >>> >>> Le 06/03/2016 06:16, paul Fultz a écrit : >>>> >>>>> On Saturday, March 5, 2016 10:50 PM, Steven Watanabe < >>> watan...(a)gmail.com <javascript:>> wrote: >>>>> >>>>> #ifndef BOOST_FIT_NO_EXPRESSION_SFINAE >>>>> #ifdef _MSC_VER >>>>> #define BOOST_FIT_NO_EXPRESSION_SFINAE 1 >>>>> #else >>>>> #define BOOST_FIT_NO_EXPRESSION_SFINAE 0 >>>>> #endif >>>>> #endif >>>> This is can be configurable, whereas Boost.Config it is not. >>> I'm not sure this is true. >>> >>> > http://www.boost.org/doc/libs/1_60_0/libs/config/doc/html/index.html#boost_… >> >> >> That doesn't seem easily configurable by the user. I think I would > prefer >> to make it configurable by the library and use Boost.Config for the default > >> value. >> > > Why does it need to be easily configurable? > No one is ever going to care about it except > when Boost.Config is wrong. Well, I guess its mainly only useful for development then. I like to use the "no expression sfinae" path on clang as I can get better diagnostics. It seems kind of complicated to change this with Boost.Config, so I would prefer to have it easily configurable, and then use Boost.Config for the default value.

1 0

[property_tree] Two pull requests removing rtti and exception dependencies
by Chris Glover 09 Mar '16

09 Mar '16

Hi, I have two pull requests against property tree that I haven't heard anything about.. The first replaces usage of typeid(Type).name() in exception messages with boost::typeindex::type_id<Type>().pretty_name(). The second uses macros from no_exception_support.hpp to replace try catch blocks. I was hoping these might get into 1.61 so I don't need to carry local changes for too long -- is there any chance of that? Links: https://github.com/boostorg/property_tree/pull/20 https://github.com/boostorg/property_tree/pull/21 Thanks, -- chris

1 0

[Fit] review - ends next 13th Mars
by Vicente J. Botet Escriba 08 Mar '16

08 Mar '16

Hi, we are on the middle of the Fit review stated on 2 Mars and that ends 13th Mars. We have not received a lot of comments, only 4 or 5 people have commented and only a formal review (reject now). I understand that the documentation needs a lot of improvements, nevertheless, this review is the occasion to give as much feedback as possible. If you want to improve this library, please take the time to do a review and share your point of view. Best, Vicente

1 0

[coroutine] Broken on all compilers.
by Rene Rivera 08 Mar '16

08 Mar '16

Coroutine on master branch seems broken across all the master tested compilers in the same way. Would be nice if it gets fixed. -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

2 1

[release] Reminders..
by Rene Rivera 07 Mar '16

07 Mar '16

Boost was closed for "major changes" last Wednesday. Boost will be closed for all change this Wednesday (9th). If all goes well.. Boost will reopen for bug fixes only on the 17th. Please consult the calendar, and subscribe, to the calendar for such dates < http://www.boost.org/development/index.html>. -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

4 6

[BGL] Multiple Start Vertices in Dijkstra Shortest Path
by Matthias Fuchs 07 Mar '16

07 Mar '16

Hi folks, I am interested in adding support for multiple start vertices for the Dijkstra Shortest Path Algorithm. Having such functionality would improve both performance and clarity of code I wrote. In a prove of concept I implemented such functionality using iterators for dijkstra_shortest_paths_no_color_map. Is there interest for such a feature? Or would it be a waste of my time working on that? If there is interest what should be the preferred way? * Using iterators (first_start_vertex, last_start_vertex) * Using ranges What about unit tests? AFAICT there are only few tests, which do not seem to be run automatically. What about documentation? Thanks for reading, Matthias

1 0

2 regression test failing at under 1.60
by Steven Kelso 07 Mar '16

07 Mar '16

I've just started trying to install version 1.60 of boost using the gcc 5.3.0 compiler. With a vanilla download and no chnages it all seems to compile correctly, but I have a problem with 2 library regressions tests not terminating. They have both run for over 18 hours before I had to kill them. I was using the options and configuration "out of the box" so optimization was -O3. I downloaded the regressions tests from https://github.com/boostorg/regression and installed in the boost source tree under 'tools' I then compiled and run them : B=$PWD cd tools/regressions-develop/build $B/b2 --boost-root=$B export PATH=$B:$B/tools/regression-develop/stage/bin:$PATH cd $B/lib/maths/test b2 threading=multi variant=release toolset=gcc-5.3.0 test_binomial_real_concept2 The last few lines of the output file are: test_binomial.cpp(671): error: in "test_main": check x == (RealType)floor(binomial_quantile_data[i][3]) has failed [60 != 61] test_binomial.cpp(673): error: in "test_main": check x == (RealType)floor(binomial_quantile_data[i][4]) has failed [61 != 64] test_binomial.cpp(673): error: in "test_main": check x == (RealType)floor(binomial_quantile_data[i][4]) has failed [60 != 59] test_binomial.cpp(673): error: in "test_main": check x == (RealType)floor(binomial_quantile_data[i][4]) has failed [60 != 59] the same looping forever occurs with test_binomial_real_concept4 as well. However, editing the Jamfile.v2 file to add an entry '<optimization>off' for the test, allows the test to complete successfully and the test_binomial_real_concept2.output having no errors. I've done the same test using gcc 5.2.0 and gcc 5.1.0 as well with the same results. However, boost 1.56 using gcc 5.3.0 completes all of it's tests successfully. Is this a known issue or, if not, is there any more information that I can supply to help diagnose why this isn't working? Many thanks, S

2 2

Recommended Boost file structure?
by Paul A. Bristow 07 Mar '16

07 Mar '16

I've been looking at the structure of Phil Bouchard's prototype block_ptr library and am wondering if the structure of the header files is optimal/Boost_Standard/wrong. http://www.boost.org/doc/libs/1_60_0/more/getting_started/windows.html describes the Boost structure, but looks well out of date to me. (Can/should anyone still update this to reflect Modular Boost?) And looking through libraries, there seems some variation. I'm asking for views on what the best structure should be, (or if it doesn't matter much?) Some libraries have a structure modular_boost/libs/algorithm/include/boost/algorithm which contains algorithm.hpp and string.hpp that one might use directly. Others like asio contain /asio and just a asio.hpp that includes (all?) other headers. Others like multiprecision contain just a single folder modular_boost/libs/algorithm/include/boost/multiprecision but no other header files, not even forwarding header(s). So should the structure be that all headers (except forwarding headers - or a single header) are within modular_boost/libs/some_library/include/boost/some_library/ so the user should include with #include <boost/some_library/some_header.hpp #include <boost/some_library/other_header.hpp ... or to get everything useful #include <boost/some_library/some_library_fwd.hpp> possibly with a /detail folder containing headers that should not be called by users. Just checking... Paul --- Paul A. Bristow Prizet Farmhouse Kendal UK LA8 8AB +44 (0) 1539 561830

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Re: [boost] [Boost-users] [Fit] formal review - should we propose some parts to Boost.Config/Boost.Core
by paul Fultz 07 Mar '16

07 Mar '16

> On Saturday, March 5, 2016 10:50 PM, Steven Watanabe <watanabesj(a)gmail.com> wrote: > > AMDG > > On 03/05/2016 07:21 PM, Vicente J. Botet Escriba wrote: >> >> I want to start a new sub-thread about some of the concerns of Steven >> Watanabe about whether some of the contents of this library fits better >> in Boost.Config. In particular the file boost/fit/returns.hpp. >> > > When I mentioned Boost.Config, I was talking about > things like > > #ifndef BOOST_FIT_NO_EXPRESSION_SFINAE > #ifdef _MSC_VER > #define BOOST_FIT_NO_EXPRESSION_SFINAE 1 > #else > #define BOOST_FIT_NO_EXPRESSION_SFINAE 0 > #endif > #endif This is can be configurable, whereas Boost.Config it is not. > > or > > #ifndef BOOST_FIT_HAS_TEMPLATE_ALIAS > #if (defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 > && > __GNUC_MINOR__ < 7) > #define BOOST_FIT_HAS_TEMPLATE_ALIAS 0 > #else > #define BOOST_FIT_HAS_TEMPLATE_ALIAS 1 > #endif > #endif > This could be replaced with Boost.Config, however, I have ran into problems before with template aliases on gcc 4.7, so I wanted to make this configurable as well, although it could fallback onto Boost.Config right now. > In Christ, > > Steven Watanabe > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users >

3 2

[MMap/VM] RFC
by Domagoj Saric 06 Mar '16

06 Mar '16

Hello everyone, for quite some time I've been working on a portable mmap/virtual memory library and I've finally found enough time to bring it out of the 'my internal litle tool' state into something presentable: https://github.com/psiha/mmap (C++14 currently). I would now kindly ask fellow devs for opinions (on the good, the bad, the ugly and the future;) First let me answer the basic questions (i.e. on motivation and scope)... Q&A: (1) Why? Considering Boost already offers two related solutions * Interprocess: http://www.boost.org/doc/libs/release/doc/html/interprocess/sharedmemorybet… * Iostreams: http://www.boost.org/doc/libs/release/libs/iostreams/doc/classes/mapped_fil… why do we want a new one? Even if the two mentioned solutions were adequate, the problem domain would still merit a separate, dedicated library merely considering its complexity (which will become apparent in later points). (I suspect Ion would agree here considering he actually authored a related standardization proposal:) (2) Why a completely new library instead of a repackaging of existing functionality? I'm not satisfied with (a) the API semantics/design, (b) the API 'power'/library capabilities (c) and the implementation efficiency/overhead. a) Insistence on POSIX semantics: that shared memory objects have to be persistent (kernel lifetime) and resizable while not everyone wants or needs this (https://svn.boost.org/trac/boost/ticket/4827) This has implications both: - in the interface (requiring manual cleanup guards, additional platform specific shm types like windows_shared_memory) - and the overhead of the library (emulating shm with mapped files on major platforms that do not offer full POSIX compliance: Windows, OSX, iOS and Android) MMAP solves this with one class template 'named_memory' and policies: https://github.com/psiha/mmap/blob/master/include/boost/mmap/mappable_objec… so the user can choose: named_memory<scoped, resizable>, named_memory<persistent, fixed> or any other combination and the library chooses the best implementation. On POSIX, scoped semantics are achieved with a SEM_UNDO-enabled SysV semaphore acting as a kernel/system-global reference counter (which is then also used for automatic cleanup of shm zombies left by killed/crashed processes). On Windows the user can choose the Win32 backend (file emulation) or the NativeNT (not yet finished/commited) backend (with native persistence and resizability). b) - lack of a meta layer (e.g. so one can ask is_mappable<FILE *> or is_mappable<boost::filesystem::path>, is_mappable<HANDLE> etc...) - lack of related utility functions, for example: -- map_read_only_file( path ) which will open the file for reading, query its size, create a read only file mapping and map/return a read only view of the file -- guarded_operation( view, operation, error_handler ) - execute operation wrapped in SEH(Windows)/scoped signal handler(POSIX) guards that will catch access violations (e.g. when mmaping network files) and gracefully execute error_handler (with the faulting address as the parameter) https://github.com/psiha/mmap/blob/master/include/boost/mmap/mapped_view/gu… - in MMAP the mapped_view object (which should probably be renamed to just 'view' considering the enclosing mmap namespace) is just a RAII wrapper around an iterator_range therby providing the standard begin/end(), front/back(), operator[], etc. interface (as opposed to a get_data(), get_size() like interface) - general (not specific to mapping) virtual memory functionality (to be discussed in a separate point, MMAP also completely lacks this currently) - MMAP offers a comprehensive 'flags' system (e.g. https://github.com/psiha/mmap/blob/master/include/boost/mmap/flags/flags.hpp) for everything from object-level and system-level access privileges, over object parent-child inheritance to system life-time and access-pattern optimisation hints. Quite some time was invested in this area to produce a normalized interface that works for all objects (files, mappings...) while producing (near)zero adjustment codegen. Flags are 'packed'/grouped in structs (e.g. struct access_privileges with object_access, child_access and systen_access members) with public members so that, after flags are created with a factory function (a portable API) the flags can be further tweaked for a specific platform (e.g. adding some FreeBSD specific mmap hint which isn't covered by the portable/documented MMAP API) c) It is my view (if not a "self evident truth";D) that libraries that merely wrap existing low level functionality (such as OS or CRT APIs) should allow you to write code that is safe, portable and looks reasonably nice while at the same time incurs (near)zero overhead (i.e. with a reasonably intelligent compiler, produces codegen that looks nearly the same as it would had one used the underlying API directly) - and the existing solutions fail that. In the two related tickets I went into more detail on this so I'll avoid spaming this post by repeating those objections and analysis. Rather I'll present a trivial example that demonstrates what wannabeboost::mmap currently produces with a decent compiler, https://gist.github.com/psiha/c0823fefc01fa3b39662: #define BOOST_MMAP_HEADER_ONLY #include <boost/mmap/mapped_view/mapped_view.hpp> #include <boost/mmap/mappable_objects/file/utility.hpp> int main( int /*argc*/, char * /*argv*/[] ) noexcept { auto maybe_foo_view( boost::mmap::map_read_only_file( "foo" )() ); if ( !maybe_foo_view ) return static_cast<int>( maybe_foo_view.error() ); if ( maybe_foo_view->empty() ) return -1; return (*maybe_foo_view)[ 0 ]; } with Xcode 7.2.1 Clang -O3 build for x64 produces https://gist.github.com/psiha/f92a7b8a93c5ce1736ae (notice how the error handling is also correctly detected as such and placed at the end of the function, after the main return...) Besides not using shared_ptr pimpls or saving paths in std::strings as a 'nice to have' (YAGNI!:), part of the way this codegen is achieved is through the use of (also wannabe) Boost.Err (https://github.com/psiha/err) which makes it possible to avoid EH (in such simple/'localised' examples). It is also the reason for the somewhat awkward (optional<>-like) syntax: - map_read_only_file() returns a mmap::fallible_result<mmap::mapped_view> (an alias for err::fallible_result<mmap::mapped_view, mmap::error>, an "rvalue-only" type) - which is converted/'saved'/'pinned' into a result_or_error (the maybe_foo_view variable) with the additional operator() call - the !maybe_foo_view checks whether the call succeeded or the returned object contains an error - if error return the error (errno) code - else check if the view/file is empty (optional<>-like syntax for accessing the contained object through the -> and * operators) - else return the value of the first character in the file. Boost.Err was recently discussed on this list so I'll skip most of that now, let me just say that it also supports classic EH coding style (it auto adapts, no need for reconfiguration, macros or anything like that), i.e. the above code can be rewritten as: int main( int /*argc*/, char * /*argv*/[] ) noexcept { using namespace boost::mmap; try { read_only_mapped_view const foo_view( map_read_only_file( "foo" ) ); if ( foo_view.empty() ) return -1; return foo_view[ 0 ]; } catch ( std::runtime_error const & ) { return error::get(); } } ...now let me reverse the Q&A direction ;) 3. Library scope: currently the library covers the topic of memory mapping (of filesystem objects and virtual memory), however I think that 'the final' library should cover all resonably portable aspects of virtual memory (and be called something like vm with mmap as a nested namespace), tackling thingies such as: - process working set - portable low memory event handling, madvise, memfd... - prefetching, locking/unlocking virtual memory to/from physical memory (e.g. for realtime sensitive data) - allocators capable of contiguous resizing (for implementing realloc or vector.resize() that does no copying or moving, simply maps new pages at the end of the current allocation) - https://fgiesen.wordpress.com/2012/07/21/the-magic-ring-buffer ... does anyone have an objection/different approach to this? 4. Windows offers/has/uses the concept of an intermediate "mapping" object (i.e. you don't create a mapped view of a file, rather you create a 'mapping' of a file and then a view of the mapping). This of course complicates things but also gives more power, e.g. you can have a r/w file open and create a mapping (or several mappings) of it that only covers a part of its size and has stricter (e.g read only at object/process level) or wider access privileges (e.g. on the system level, only the parent process/user can access the file but the mapping is accesible by everyone). Boost.MMAP retains this distinction in its API (mapping vs mapped_view classes)...comments/thoughts on this please? 5. The above (Windows specific) 'mapping' concept makes it possible to create "named file mappings" (so that the object gets a system global name, like a shared memory object) which then another process can open by its name, erasing the difference between file mappings and vm mappings for client processes (kind of like the interface vs hidden implementation distinction). MMAP uses this on Windows for file-backed/'emulated' shared memory (e.g. that which needs persistence and/or resizabilty) - it is created named so that client processes can open and access it as 'normal'/native Windows shared memory. It might actually be possible to make this at least partially portable to POSIX systems that use virtual filesystems for implementing shared memory (e.g. Linux which uses /dev/shm) where we could symlink the file to the shm filesystem directory...(unfortunately I have no way of testing this as I have no Linux machine setup, I develop only for Windows, OSX, iOS and Android)...does this make any sense/would it be worth the hassle (i.e. ease any real world problems)? 6. The security part of the 'flags system' models the POSIX API: for named (system level) created objects you specify the permissions for the 'user', 'group' and 'world'. 'Behind the scenes', on Windows, 'user' maps to the user that created the process, 'group' maps to all groups that the 'user' belongs to and 'world' maps to the Everyone group..? When not using the predefined privilege/permission levels [e.g. process_default, unrestricted, nix_default (644)] things are currently pretty verbose here: namespace flags = boost::mmap::flags; using ap = flags::access_privileges; auto const default_privileges ( ap::system::user ( ap::all ) | ap::system::group( ap::read ) | ap::system::world( ap::read ) ); I have a prototype implementation that shortens this with user defined literals, so that one can write something like "rwxr-xr--"_perm...All in all, this thing looks like it merits a separate library in its own right... 7. Windows has another quirk up its sleeve: global vs local session objects - if you want to create a shared memory object visible across terminal sessions (this includes a server process running as a service, thereby in session 0, and client process created by a logged on user, or/also using the NativeNT backend/API to create a native persistent shared memory object which requires that it be created in the global session '0') you have to prefix its name with "Global\" (and have admin privileges)... I'm still pondering how to model this in the API or whether it should be automatically handled at all, e.g. whether to deduce if the Global\ prefix should be automatically added (based on the process privileges, type and access privileges of shm object being created etc) or leave it up to the user to know "if I'm running on Windows and want to do this and this I have to use the Global\ prefix"... There's more but the openning post is already too long so I'l stop...for now ;) -- "What Huxley teaches is that in the age of advanced technology, spiritual devastation is more likely to come from an enemy with a smiling face than from one whose countenance exudes suspicion and hate." Neil Postman --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

4 5

code naming conventions
by Michael Marcin 06 Mar '16

06 Mar '16

I've written a lot of code in the boost/standard library style. I've become increasingly annoyed at naming my variables when coding in this style. Looking to the standard library implementations for guidance isn't much help as they often use conventions like local variables are named with a leading double underscore and member variables are named with a leading underscore and capital letter. I.E. things I'm not allowed to do as I'm not a standard library implementer. Good names are generally taken by types leading to distress when trying to name objects and functions. Here's a concrete example: // type takes the most natural name enum class format { rgba, rgb, float // enum value wants reserved name }; class image { public: // getter wants the same name format format() const noexcept { return this->format; } // setter wants the same name void format( format format ) noexcept // parameter wants the same name { this->format = format; } private: // member variable wants the same name format format; }; format bits_to_format( int bits ) { // local variable wants the same name format format = format::rgba; if ( bits == 24 ) { format = format::rgb; } return format; } // unrestricted template parameter does *not* want the same name template< typename Format > std::ostream& print_format( std::ostream&, Format format ); // Concept template parameter *does* want the same name template< Format Format > std::ostream& print_format( std::ostream&, Format format ); What I end up doing right now is something like: // type takes the most natural name enum class format { rgba, rgb, float_ // add trailing underscore to reserved name }; class image { public: // prefix getter with get_ format get_format() const noexcept { return _format; } // prefix setter with get_ void set_format( format format_ ) noexcept // trailing underscore on parameter { _format = format_; } private: // leading underscore on member format _format; }; format bits_to_format( int bits ) { // cutesy abbreviation for local variable format fmt = format::rgba; if ( bits == 24 ) { fmt = format::rgb; } return fmt; } template< typename Format > std::ostream& print_format( std::ostream&, Format format_ ); // cutesy abbreviation for constrained template type template< Format Fmt > std::ostream& print_format( std::ostream&, Fmt format_ ); Having to come up with cutesy abbreviations for every local variable that are still meaningful is especially distracting. Surely enough code has been written that this has been solved. I looked through several boost library implementations but didn't see anything that stuck out as a clear convention. Adobe's ASL library seems to append _t postfix to type names and _m postfix to member variables. They also use very terse names for template parameter type names as well as parameter names and local variables. Like in: template <typename I, // I models ForwardIterator typename N, // N models IntegralType typename T, // T == result_type(P) typename C, // C models StrictWeakOrdering(T, T) typename P> // P models UnaryFunction(value_type(I)) -> T I lower_bound_n_(I f, N n, const T& x, C c, P p) { while (n != 0) { N h = n >> 1; I m = boost::next(f, h); if (c(p(*m), x)) { f = boost::next(m); n -= h + N(1); } else { n = h; } } return f; } What's your preferred convention? If possible please answer by modifying the initial concrete example and providing annotations.

3 2

[MSM] Surprising Entry Point behaviour
by Michael Caisse 06 Mar '16

06 Mar '16

Hi Christophe - I'm seeing some surprising behaviour when I have a sub-machine that can only be entered via an entry point. I have attached a diagram for quick reference. Code is below to demonstrate the "issue". Moving into the Sub state should only generate transitions into A with a 'none' event. The only way to get to B is via a transition from A with the 'event' event. MSM is trying to generate code into B for a transition with a 'none' event. This could be valid if the transition from Top::X wasn't via the entry point and just directly to Sub. I don't think there is a path to B with a 'none' event. Thoughts? Take care - michael ---------------- #include <boost/msm/front/state_machine_def.hpp> #include <boost/msm/front/functor_row.hpp> #include <boost/msm/back/state_machine.hpp> using boost::msm::front::none; using boost::msm::front::Row; namespace msm = boost::msm; struct event { int foo; }; struct Sub_ : public msm::front::state_machine_def<Sub_> { struct Enter : public msm::front::entry_pseudo_state<0> {}; struct A : msm::front::state<> {}; struct B : msm::front::state<> { template<class FSM> void on_entry(event const & evt, FSM &) {} }; using initial_state = A; struct transition_table : boost::mpl::vector< // Start Event Next Action Guard // +----------+---------+--------+-----------+-------- Row < Enter , none , A , none , none >, Row < A , event , B , none , none >, Row // +----------+---------+--------+-----------+-------- >{}; }; using Sub = msm::back::state_machine<Sub_>; struct Top_ : public msm::front::state_machine_def<Top_> { struct X : msm::front::state<> {}; using initial_state = X; struct transition_table : boost::mpl::vector< // S Event Next Action Guard // +----+-------+-----------------------------+-------+------- Row < X , none , Sub::entry_pt<Sub_::Enter> , none , none > // +----+-------+-----------------------------+-------+------- >{}; }; using Top = boost::msm::back::state_machine<Top_>; int main() { Top top; top.start(); } ------------------------- -- Michael Caisse Ciere Consulting ciere.com

2 1

Re: [boost] [Boost-users] [Fit] formal review - should we propose some parts to Boost.Config/Boost.Core
by Glen Fernandes 06 Mar '16

06 Mar '16

On Sat, Mar 5, 2016 at 9:21 PM, Vicente J. Botet Escriba wrote: > Others could be considered also as function.hpp, lambda.hpp and lift.hpp, as > the macros are there to workaround some missing language features, but those > are much more specialized (Boost.Core?) > Boost.Core is where we move code from existing Boost libraries that enables breaking cyclic dependencies between different Boost libraries. I'm not so sure new libraries will need to (or want to) put code there. Glen

2 1

[Fit] review
by Vicente J. Botet Escriba 06 Mar '16

06 Mar '16

Paul, could you send me a private mail, I don't reach to send you any private mail. I'm always getting Hallovicente.botet(a)wanadoo.fr, Sie erhalten diese E-Mail, weil die Gruppe, die Sie kontaktieren möchten (boost-devel-archive), möglicherweise nicht vorhanden ist bzw. Sie nicht die erforderlichen Berechtigungen haben, um der Gruppe Nachrichten zu posten. Nachstehend einige Detailinformationen zu den möglichen Gründen, warum Sie keine Nachricht posten konnten: ... :( Vicente

1 0

[Fit] review - github issuess
by Vicente J. Botet Escriba 06 Mar '16

06 Mar '16

Hi, we have started to create some issues in https://github.com/pfultz2/Fit/issues, and sometimes there are some interesting discussion. I will try to add post on the MLs the issues that are conflicting so that other are aware of the discussion. Anyway, if you are curious you can always take a look at and participate also. If you want to receive the updates I believe that you just need to click on watch (top right). Best, Vicente

1 0

[asio] Feature request: console IO
by Tatsuyuki Ishi 06 Mar '16

06 Mar '16

Hello everyone, here is a greeting for joining the list. I want to request console support in asio. Some reasons: 1. non-block stdin is useful for some applications. 2. Linux can do non-block IO on ttys. Implementation concept: 1. Linux: if using epoll, first check if target is a regular file. If not, fall back to threaded non-blocking IO. select(), poll() can be use on any valid fds. 2. Windows: this garbage doesn't support overlapped console IO. Create a separate thread for std{in,out,err}, then communicate with the thread. 3. Other *nix: I don't know. It could already be used through POSIX stream descriptor, but it is too limited and platform specific. A library can cover these gaps is great. I hope you like this idea.

3 2

[Block Pointer][Container] Works - Take 2
by Phil Bouchard 06 Mar '16

06 Mar '16

Sorry for all the confusion but I was very confused myself. Now the block_ptr<> works in all cases with Linux x86: - I removed the usage of an allocator. Now there is no need for any allocator anymore. - I removed the usage of the strange pointer proxy optimization. Now the memory manager might take more memory but the class is clean and correctly abstracted. - I removed the usage of weak references. This is just too error-prone. But I need to tell whether an address is on the stack or on the heap. There is no portable way to do this except from marking the heap boundaries by overloading an allocator or write assembly code for each architecture / OS. I prefer the latter and I think this should eventually be part of the standards. Once again the working examples are here: https://github.com/philippeb8/block_ptr/blob/master/example/benchmark.cpp https://github.com/philippeb8/block_ptr/blob/master/example/block_ptr_test1… https://github.com/philippeb8/block_ptr/blob/master/example/block_ptr_test2… Regards, -Phil

3 6

merge to master?
by Robert Ramey 05 Mar '16

05 Mar '16

I've (finally!) got the latest version of the serialization library to pass all the tests on develop. I would like to merge develop to master. May I do this? Robert Ramey

2 4

[Block.Pointer][Container] Works!
by Phil Bouchard 05 Mar '16

05 Mar '16

Ok now everything works!! https://github.com/philippeb8/block_ptr/blob/master/example/block_ptr_test2… So now block_ptr<> is Boost.Container compliant! I still need to fix an issue but it's moving forward! Thanks, -Phil

3 7

[test] Boost.Test fails to build with gcc-4.6
by John Maddock 05 Mar '16

05 Mar '16

See http://www.boost.org/development/tests/develop/developer/output/igaztanaga-…

3 2

[Fit] pipable order of the arguments
by Vicente J. Botet Escriba 05 Mar '16

05 Mar '16

Hi, I would like to know what other think about the order of the pipe (See this issue https://github.com/pfultz2/Fit/issues/5) What would be the expected meaning of auto r1 =1 | pipable(f)(2); f(1,2) or f(2,1)? What would be the expected meaning of auto f2 = partial(f)(2); auto r1 =1 | pipable(f2); f(1,2) or f(2,1)? As the operator| has left-to-right associativity, we can not do auto x = 1 | 2 | pipable(f); We would need a way to pack the parameters auto x = forward_as_tuple(1, 2) | pipable(f); but this wouldn't compile as f has two parameters. or use parenthesis auto x = 1 | (2 | pipable(f)); and the result will be f(2, 1). Any ideas? Best, Vicente Vicente

1 1

[fusion] getting type of attribute_proxy for BOOST_FUSION_ADAPT_ADT
by Jens Weller 05 Mar '16

05 Mar '16

Hello, Code below, first what I'm trying to do is... assign a value to a adapted struct (BOOST_FUSION_ADAPT_ADT), which works fine if both are of the same type or convertible: template<int I, class Seq, class V> typename std::enable_if< std::is_convertible< typename fusion::result_of::at_c<Seq, I>::type, V>::value ,void>::type assign(Seq& s, V& v) { fusion::get(s) = v; } Some of my input is string, and the struct member is bool, unsigned int etc. In this case I'd need to know the type to convert from string. boost::fusion::get returns the attribute_proxy for the adapted struct, so does at_c<>::type. template<int I, class Seq, class V> typename std::enable_if< !std::is_convertible< typename fusion::result_of::at_c<Seq, I>::type, V>::value /*&& !std::is_same<typename std::decay<V>::type,std::string>::value*/ ,void>::type assign(Seq& s, V& v) { std::stringstream ss; ss << v; ss >> fusion::get(s); } Obviously this does not compile. Is there any trick to get to the type of the proxy? One idea I have is decltype(fusion::get(s).get()), but not sure if I can get this to work in an enable_if... thanks, Jens Weller

3 5

[operators] permission to merge develop to master
by Daniel Frey 05 Mar '16

05 Mar '16

May I merge the ADL protection from develop to master for utility/operators?

2 3

[optional] Why was optional<T>::reset() deprecated?
by Nevin Liber 04 Mar '16

04 Mar '16

Does anyone know? We are considering adding it to std::optional this week. Thanks, -- Nevin ":-)" Liber <mailto:nevin@cplusplusguy.com <nevin(a)eviloverlord.com>> +1-847-691-1404

7 15

[type_traits] is_base_of<B, D> should work when B is incomplete
by Andrzej Krzemienski 04 Mar '16

04 Mar '16

Hi, I have filed the following ticket: https://svn.boost.org/trac/boost/ticket/12027 The Standard ([meta.rel]) requires that in std::is_base_of<B, D> D must be a complete type, but it does not require the same of B. This makes sense, because if we compare a complete type D and an incomplete type B, the former is surely not derived from the latter. In contrast, boost::is_base_of imposes an additional constraint that B must also be complete. Could this restriction be lifted? Regards, &rzej

8 14

[range] merge to master?
by Jürgen Hunold 04 Mar '16

04 Mar '16

Hi Neil, could you please merge Boost.Range to master? There are some merged PRs fixing bugs in develop which I'd like to see in 1.61.0 Yours, Jürgen -- * Dipl.-Math. Jürgen Hunold ! * voice: ++49 4257 300 ! Fährstraße 1 * fax : ++49 4257 300 ! 31609 Balge/Sebbenhausen * jhunold(a)gmx.eu ! Germany

1 0

Re: [boost] [Fit] upcoming formal review for Boost.Fit
by Bjorn Reese 03 Mar '16

03 Mar '16

On 02/27/2016 05:16 PM, Vicente J. Botet Escriba wrote: > Documentation:http://pfultz2.github.io/Fit/doc/html/ In More Examples / Projections there is this example: std::sort(std::begin(people), std::end(people), by(&Person::year_of_birth, _ < _)); That strikes me as a very terse syntax, where the reader could easily miss the fact that two values are being compared. Have you considered the use of placeholders like _1 and _2 instead?

4 4

[Block.Pointer][Container] List node allocator
by Phil Bouchard 02 Mar '16

02 Mar '16

I've refactored most of the internal algorithms of block_ptr<> and now it is much more robust. The following example works pretty well: https://github.com/philippeb8/block_ptr/blob/master/example/block_ptr_test1… The next step is to support Boost.Containers: https://github.com/philippeb8/block_ptr/blob/master/example/block_ptr_test2… But after debugging the code it looks like the allocator is not used to instantiate the nodes and I do not see how it is used by looking at the code: template <class T, class VoidPointer> struct list_node : public list_hook<VoidPointer>::type { private: //list_node(); public: typedef T value_type; typedef typename list_hook<VoidPointer>::type hook_type; T m_data; T &get_data() { return this->m_data; } const T &get_data() const { return this->m_data; } }; Am I missing something? Thanks a lot for your help, -Phil

3 8

[gsoc16] Boost rejected as GSoC 2016 org
by Niall Douglas 02 Mar '16

02 Mar '16

Dear Boost, It is with a heavy heart I write to say that Boost was rejected as an org for Google Summer of Code 2016 by Google. We had our application submitted in time, it was reviewed by three members of the Boost leadership, our ideas list had six solid ideas with an especially solid seventh on the way, we were in very good standing with Google and there was no reason to expect rejection. We have asked for clarification as to why we were rejected, and we shall try to improve our application next year to improve our chances. We recognise that many students and mentors will be extremely disappointed by this news. We share in that disappointment, and all we can say is please try again next year. For those students and mentors who are continuing a previous GSoC on an existing Boost library, there may be a possibility that Boost may be able to fund those continuations this year. Each case will be approached by the steering committee on a case by case basis, and be aware that the standard required for funding by Boost is considerably above that of Google's with an accompanying high and detailed standard of funding application to the steering committee. Contact us privately if you want to know more. On other news we had been expecting to announce today that Bryce Adelstein Lelbach has generously agreed to take over as secondary GSoC admin from Boris Schäling who has served Boost GSoC for something like four years now, so he has definitely earned himself a rest! Our thanks to Boris for his service, and welcome Bryce to the team! Finally, I'd like to thank Jon Kalb who moved heaven and earth as he always does to get the GSoC application submitted in time. Yours, Niall Douglas -- ned Productions Limited Consulting http://www.nedproductions.biz/ http://ie.linkedin.com/in/nialldouglas/

18 24

Re: [boost] [gsoc16] An update on GSoC 2016 contingency plans
by Bjorn Reese 02 Mar '16

02 Mar '16

On 03/02/2016 05:17 PM, Niall Douglas wrote: > * Boost.Http, mentored by Bjorn Reese. > https://boostgsoc14.github.io/boost.http/ > > Student: Vinícius dos Santos Oliveira > > Status: One peer review held I have been preparing a proposal for GSoC 2016 which got delayed due to the usual excuses (work-load.) This is a draft of the proposal: Title: HTTP parser combinator. This proposal explores a more flexible HTTP parser framework based on ideas from parser combinators and pull parsers. The framework differentiates itself from the existing HTTP parser libraries for C/C++ on several accounts. With the help of parser combinators it offers the possibility of parsing an entire HTTP message or just a piece of it. The framework should consist of mini-parsers for the individual BNF rules in the HTTP grammar [1]. This is useful when integrating with existing HTTP transport libraries, such as libcurl, which may deliver one HTTP header at the time through a calllback mechanism. Pull parsers gives us the opportunity to replace the parser during the parsing process. This is useful for HTTP Upgrade requests, where the grammar may change "in-flight." For example, WebSockets starts off using the normal HTTP grammar, but then changes to its own binary protocol. Other examples are the differently formatted data that occurs in HTTP messages, such as x-www-form-urlencoded [2] or JSON [3]. Pull parsers also allows for smaller memory footprint. [1] https://tools.ietf.org/html/rfc7230 [2] https://www.w3.org/TR/html401/interact/forms.html#h-17.13.4.1 [3] https://tools.ietf.org/html/rfc7159

1 0

[gsoc16] An update on GSoC 2016 contingency plans
by Niall Douglas 02 Mar '16

02 Mar '16

Dear Boost, We've been collecting a list of veteran Summer of Code students where "veteran" means students whom have previously done a Google Summer of Code for Boost. It /may/ be possible for us to acquire enough funding from a number of contributors to tide over ongoing GSoC projects this summer during our year off from Google funding for veteran students only. The stipend to the student would be the same as with Google, $5,500. The mentor stipend would likely need to be waived under any substitute programme. We would therefore appreciate an update from student and/or mentor as to whether they were intending to submit a continuing GSoC this summer and would be willing to continue work on their Boost library under any funding we find. If we have forgotten any students or projects, please get in touch. Extant ongoing summer of code projects known to us are (please send corrections of any mistakes): * Boost Document, mentored by Antony Polukhin. https://anuragxel.github.io/boost-document/ Student: Anurag Ghosh Status: Not peer reviewed * Boost.Compute, mentored by Kyle Lutz. https://boostorg.github.io/compute/ Student: Jakub Szuppe Status: Official Boost library * Boost.Hana, mentored by Joel Falcou. https://boostorg.github.io/hana/ Student: Louis Dionne Status: Official Boost library * Boost.Http, mentored by Bjorn Reese. https://boostgsoc14.github.io/boost.http/ Student: Vinícius dos Santos Oliveira Status: One peer review held * Boost.Fixed-Point, mentored by Paul Bristow. https://github.com/BoostGSoC15/fixed_point Student: Nikhar Agrawal Status: Not peer reviewed We are aware of the following Boost libraries who have strong but new-to-Boost potential student candidates in the pipeline for summer of code 2016: * Boost.odeint, mentored by Karsten Ahnert and Mario Mulansky There is even less chance we can find funding for these, but if any of the veteran students or mentors has to suddenly pull out before the summer, we would substitute one of these projects instead. Therefore, if mentors had a really excellent student lined up for 2016, please let us know. None of the above should be read that summer of code 2016 is going ahead. We just need some hard numbers with which to lobby for funding. We will get back to the community as soon as we know more. We need all this information requested above back BEFORE this weekend as we will be making use of the Jacksonville ISO WG21 meeting currently happening to grab the right people to ask them for donations from their corporate bodies. If YOUR corporate org would be willing to help sponsor a summer of code student, either partially or in full, PLEASE get in touch. Donations to Boost are tax deductible for US taxpayers. Thank you all very much in advance! Niall --- Boost C++ Libraries Google Summer of Code 2016 admin https://svn.boost.org/trac/boost/wiki/SoC2016

3 2

[serialization] Back Versioning issue
by Janusz Zradomia 02 Mar '16

02 Mar '16

We want to use boost::serialization with boost::asio in one of our software, but we have a critical issue which prevents our further work. It refers to the "Back Versioning" known problem in TODO section: "It has been suggested that a useful feature of the library would be the ability to create "older versions" of archives. Currently, the library permits one to make programs that are guaranteed the ability to load archives with classes of a previous version. But there is no way to save classes in accordance with a previous version. At first I dismissed this as a huge project with small demand. A cursory examination of the code revealed that this would not be very difficult. It would require some small changes in code and some additional tests. Also it would require special treatment in the documentation - perhaps a case study. " *We want to ask what is status of this issue and can we expect to fix this in near future.* This is a networking project, our program compiled with e.g. boost 1.62 or some future version must create archives that can be (sent over the network and then) read on the program compiled with older version like 1.57 for example (as now available by default of Windows/cygwin). We would hope that we can do something like; Archive ar; ar.set_compatibility_boost_version(1, 55); ar << ... We would also need to backport the patch to older version of boost archive, so they also can write archives readable by (even older) versions. In the end we expect to run machines with: boost 1.55 (plus patch to set compatibility) boost 1.57 (plus patch to set compatibility) boost 1.58 (plus patch to set compatibility) boost 1.62 (perhaps by default with the set compatibility option) and each of this computers needs to write archive readable by all other versions (set they would all set compatibility to lowest common version). Without this functionality we can not use boost archive in this project. We would like to help you test/backport this fix and perhaps even try to code it, although we do not yet have any experience in writing code for boost library itself. Can we expect this functionality to be written in e.g. this year? Best regards

2 1

[doc] Liven up Boost Documentation with Java Script?
by Krzysztof Jusiak 01 Mar '16

01 Mar '16

Dear Boosters, I'm writing to ask about your opinion regarding more interactive documentation for Boost. I know already that some of you would like to see online documentation without Java Script and that's absolutely fine and I agree that documentation should be available for anyone and any configuration. Nevertheless, I would like to know what the Boost community thinks about having following features in the documentation... * Run the code online (allows to check library with one click) * Comments (allows commenting on the documentation) * Chats (allows discussing issues and solutions) Personally, I have found above features extremely useful when checking out other languages/libraries and therefore I have implemented solutions for C++ too. Please, check it out (JS is required)... http://boost-experimental.github.io/msm-lite http://boost-experimental.github.io/di If there is an interest I can provide generic solution to allow developers to write documentation using markdown (mkdocs) and simply integrate it with their libraries. Currently, theme is just slightly modified version of readthedocs, however Paul Fultz II has prepared a boost theme for Fit library ( https://github.com/pfultz2/mkdocs-boost) already and it might be easily integration with the JS facilities provided. Cheers, Kris

8 26

[ublas]Contribute about Toeplitz Matrix
by Shangtong Zhang 01 Mar '16

01 Mar '16

Hi David Bellot, It’s disappointed that boost was rejected by gsoc 2016. I was interested in ublas project, and have implemented parts of toeplitz matrix. Anyway I don’t want to abandon my implementation half way, so I’d like to continue on toeplitz matrix. Would you like to guide me to succeed in integrating toeplitz matrix into ublas? Thanks, Shangtong Zhang, Senior Student, School of Computer Science, Fudan University, PRC.

2 1

Re: [boost] [Boost-users] [Fit] upcoming formal review for Boost.Fit
by paul Fultz 29 Feb '16

29 Feb '16

On Sunday, February 28, 2016 12:23 PM, Edward Diener <eldiener(a)tropicsoft.com> wrote: > > >On 2/27/2016 11:16 AM, Vicente J. Botet Escriba wrote: >> Dear Boost community, >> >> The formal review of Paul Fultz II's Fit library starts on Wednesday, 2nd March and ends on 13th March. > >How do I generate the docs or run the tests for my local copy of Fit ? > You can build and run the tests by building the check target. For those unfamiliar with cmake, first configure the build directory with cmake: mkdir build cd build cmake .. cd .. Next build the check target using the native build system(such as make or msbuild). CMake can call the native build system to build the target 'check', like so: cmake --build build --config Release --target check Also, the library can be installed by invoking the 'install' target. The documentation needs to be built using mkdocs. You can install mkdocs and the boost theme with pip like this: pip install mkdocs mkdocs-boost Then to build the documentation, first `setup.py` must be run to extract the documentation and examples from the source code, then `mkdocs` can be invoked, like this: python setup.py mkdocs build -t boost And the documentation will be in the 'doc/html' directory. Paul

4 6

C++Now Student/Volunteers Call for Applications
by Jon Kalb 29 Feb '16

29 Feb '16

The Call for Applications for Student/Volunteers for C++Now 2016 (AKA BoostCon X) has been released: http://cppnow.org/2016-conference/announcements/2016/02/23/student-volunteer -program-accepting-applications.html The application submission deadline is March 16th. We are looking for students with a strong interest in C++. The opportunity is open to student of any level or any field of study. Jon Kalb Chair, C++Now 2016

1 0

[filesystem] cygwin paths
by Steven Watanabe 29 Feb '16

29 Feb '16

AMDG Does Boost.Filesystem have any support at all for cygwin paths? I know that you want to use Windows paths internally, but this creates problems for programs that get paths from an external source. In particular, it causes the regression tests to fail when running from cygwin. See https://github.com/boostorg/regression/issues/37. else if ( !locate_root.is_complete() ) { locate_root = ( fs::initial_path() / locate_root ).normalize(); } locate_root is created by locate_root = fs::path( *args_i ); i.e. it's taken directly from the command line. In Christ, Steven Watanabe

1 0

Version mismatch
by Neil Gatenby 29 Feb '16

29 Feb '16

As per http://lists.boost.org/Archives/boost/2015/05/222520.php, I'm seeing (on master) Jamroot version set to 1.60 and version.hpp calling the release 1.61.0 I can work around the problems it's causing, but I note it, FYI Cheers Neil

1 0

[Fit] upcoming formal review for Boost.Fit
by Vicente J. Botet Escriba 29 Feb '16

29 Feb '16

Dear Boost community, The formal review of Paul Fultz II's Fit library starts on Wednesday, 2nd March and ends on 13th March. Fit is a header-only C++11/C++14 library that provides utilities for functions and function objects. Fit is: - Modern: Fit takes advantages of modern C++11/C++14 features. It support both `constexpr` initialization and `constexpr` evaluation of functions. It takes advantage of type deduction, variadic templates, and perfect forwarding to provide a simple and modern interface. - Relevant: Fit provides utilities for functions and does not try to implement a functional language in C++. As such, Fit solves many problems relevant to C++ programmers, including initialization of function objects and lambdas, overloading with ordering, improved return type deduction, and much more. - Lightweight: Fit builds simple lightweight abstraction on top of function objects. It does not require subscribing to an entire framework. Just use the parts you need. Fit is divided into three components: * Function Adaptors and Decorators: These enhance functions with additional capability. * Functions: These return functions that achieve a specific purpose. * Utilities: These are general utilities that are useful when defining or using functions Fit has been tested on gcc 4.6-4.9, clang 3.4-3.7, and Visual Studio 2015. For more information see: Github:https://github.com/pfultz2/Fit/tree/boost Documentation:http://pfultz2.github.io/Fit/doc/html/ Note that, as Fit is a functional library, the semantic of the functions is given in the form of `equations` instead of the classic effects, returns schema. This is because most of the functions have no side effects. E.g. the semantic of the function flip is defined as |assert(flip(f)(x, y, xs...) == f(y, x, xs...));| and the semantic of compose as |assert(compose(f, g)(xs...) == f(g(xs...)));| We await your feedback! Best regards, Vicente J. Botet Escriba P.S. Paul, now it is time to freeze the version that will be reviewed. I suggest you to create a branch on which you could fix the review issues.

3 2

[gsoc16] Static Map Competency test
by Karim Tarabishy 28 Feb '16

28 Feb '16

Hello, I have some questions regarding the test: 1) You have asked why did I chose this constexpr hashing function, do you mean this for the hashing algorithm it self like its collision rate and speed relative to other hashing algorithms? 2) I wanted to check about the elegant and useful error for the case of using an array of different size or using non string literals, does the error message appearing here http://melpon.org/wandbox/permlink/TFEP1yUc7pjukowH suffice? 3) Can I have feedback on the code and the simple tests? http://melpon.org/wandbox/permlink/HiFu9KXClEWDS1Of Thanks in advance. Karim Amr, Seniors Class, Software Engineer -- View this message in context: http://boost.2283326.n4.nabble.com/gsoc16-Static-Map-Competency-test-tp4683… Sent from the Boost - Dev mailing list archive at Nabble.com.

2 3

[test-matrx] problem with testing expected compile-time failures.
by Andrzej Krzemienski 28 Feb '16

28 Feb '16

Hi Everyone, I need help trying to understand how the testing of desired compile-time failures work. I know the concept in general, but I observe something strange in test results for Optional in Master: http://www.boost.org/development/tests/master/developer/optional.html I have a test called optional_test_ref_convert_assign_const_int_prevented <https://github.com/boostorg/optional/blob/master/test/optional_test_ref_con…> It is marked (intentionally) "cf": "only try to compile and expect a failure".But on tester sun- 12.4_stlport4 the test results are marked as "comp" which indicates an *unexpected* compile-time failure. This confuses me: * I marked the test "expect compile-time failure". * Test results are marked as "unexpected compile-time failure". Am I missing something? Not to mention that there is no compiler output included: http://www.boost.org/development/tests/master/developer/output/oracle-intel… Thanks, &rzej

2 2

Test results marked as failure without errors
by Abel Sinkovics 28 Feb '16

28 Feb '16

Hi, Some of the Metaparse tests are marked as failures, however I see no errors in the output. Here are two examples (one for gcc and one for msvc) http://www.boost.org/development/tests/develop/developer/output/igaztanaga-… http://www.boost.org/development/tests/develop/developer/output/igaztanaga-… Both the compile and link steps succeed and there is nothing about the execution of the compiled code. Does someone know why these are marked as failures? Thanks, Ábel

4 5

[Container] Inner Smart Pointers
by Phil Bouchard 28 Feb '16

28 Feb '16

I have to admit MSVC 2015 got a clean STL... block_ptr_test2.cpp doesn't crash but some assertions are wrong (in my block_ptr tests). Is there any plans from Boost to make the Boost.Container work with inner smart pointers? I don't think there is any other alternative if people want to plugin memory management. Thanks, -Phil

4 16

Re: [boost] [Boost-users] [Fit] upcoming formal review for Boost.Fit
by Vicente J. Botet Escriba 27 Feb '16

27 Feb '16

Le 27/02/2016 20:18, Edward Diener a écrit : > On 2/27/2016 11:16 AM, Vicente J. Botet Escriba wrote: >> Dear Boost community, >> >> The formal review of Paul Fultz II's Fit library starts on Wednesday, >> 2nd March and ends on 13th March. > > What is the branch of Fit we are going to be reviewing ? The boost branch. The link https://github.com/pfultz2/Fit/tree/boost points directly to the repository that will be reviewed. Vicente

1 0

Maintainer of bimap
by Sebastien Loriot 27 Feb '16

27 Feb '16

Hi, Is there still somebody in charge of the bimap package? There are 2 trivial pull requests lying around since last summer. It would be nice to see them integrated. Thanks, Sebastien.

2 1

[config] config.requires and simple_run
by Steven Watanabe 27 Feb '16

27 Feb '16

AMDG I've just been trying to get MinGW working without requiring the compiler's bin directory to be in the PATH. It mostly works now, but unfortunately I ran into problems with simple_run_action. The problem essentially is that this rule ignores RUN_PATH, which may be set by some toolsets (a quick grep shows borland, cw, gcc, and intel) to indicate additional paths that must be added to PATH when running the executable. In addition, I'm wondering how this is supposed to work with a cross-compiler. We really shouldn't be requiring cross-compilers to have access to the target system for ordinary builds. In Christ, Steven Watanabe

2 4

Can't build in status?
by John Maddock 27 Feb '16

27 Feb '16

I can't seem to get building anything in the status directory working, I'm using: bjam --dump-tests msvc-14.0 -n But any combination of arguments seems to fail, the failures are: M:/data/boost/boost/tools/build/src/build\property.jam:743: in class(a)property-map.find from module object(property-map)@236 error: Ambiguous key M:/data/boost/boost/tools/build/src/build\type.jam:333: in generated-target-ps from module type M:/data/boost/boost/tools/build/src/build\type.jam:270: in type.generated-target-suffix from module type M:/data/boost/boost/tools/build/src/build\virtual-target.jam:509: in virtual-target.add-prefix-and-suffix from module virtual-target M:/data/boost/boost/tools/build/src/build\virtual-target.jam:468: in _adjust-name from module object(file-target)@149078 M:/data/boost/boost/tools/build/src/build\virtual-target.jam:253: in abstract-file-target.__init__ from module object(file-target)@149078 M:/data/boost/boost/tools/build/src/build\virtual-target.jam:561: in class(a)file-target.__init__ from module object(file-target)@149078 M:/data/boost/boost/tools/build/src/kernel\class.jam:90: in class.new from module class M:/data/boost/boost/tools/build/src/build\generators.jam:558: in generator.generated-targets from module object(gcc-linking-generator)@149065 M:/data/boost/boost/tools/build/src/tools\builtin.jam:886: in linking-generator.generated-targets from module object(gcc-linking-generator)@149065 M:/data/boost/boost/tools/build/src/tools\unix.jam:67: in generated-targets from module object(gcc-linking-generator)@149065 M:/data/boost/boost/tools/build/src/build\generators.jam:459: in construct-result from module object(gcc-linking-generator)@149065 M:/data/boost/boost/tools/build/src/build\generators.jam:412: in run-really from module object(gcc-linking-generator)@149065 M:/data/boost/boost/tools/build/src/build\generators.jam:386: in generator.run from module object(gcc-linking-generator)@149065 M:/data/boost/boost/tools/build/src/tools\builtin.jam:801: in linking-generator.run from module object(gcc-linking-generator)@149065 M:/data/boost/boost/tools/build/src/tools\unix.jam:41: in unix-linking-generator.run from module object(gcc-linking-generator)@149065 M:/data/boost/boost/tools/build/src/tools\gcc.jam:692: in class(a)gcc-linking-generator.run from module object(gcc-linking-generator)@149065 M:/data/boost/boost/tools/build/src/build\generators.jam:994: in try-one-generator-really from module generators M:/data/boost/boost/tools/build/src/build\generators.jam:1056: in try-one-generator from module generators M:/data/boost/boost/tools/build/src/build\generators.jam:1294: in construct-really from module generators M:/data/boost/boost/tools/build/src/build\generators.jam:1378: in generators.construct from module generators M:/data/boost/boost/tools/build/src/tools\python.jam:1160: in class(a)python-test-generator.run from module object(python-test-generator)@244 M:/data/boost/boost/tools/build/src/build\generators.jam:994: in try-one-generator-really from module generators M:/data/boost/boost/tools/build/src/build\generators.jam:1056: in try-one-generator from module generators M:/data/boost/boost/tools/build/src/build\generators.jam:1294: in construct-really from module generators M:/data/boost/boost/tools/build/src/build\generators.jam:1378: in construct from module generators M:/data/boost/boost/tools/build/src/build\generators.jam:1069: in generators.construct-types from module generators M:/data/boost/boost/tools/build/src/build\generators.jam:609: in convert-to-consumable-types from module object(generator)@245 M:/data/boost/boost/tools/build/src/build\generators.jam:405: in run-really from module object(generator)@245 M:/data/boost/boost/tools/build/src/build\generators.jam:386: in class(a)generator.run from module object(generator)@245 M:/data/boost/boost/tools/build/src/build\generators.jam:994: in try-one-generator-really from module generators M:/data/boost/boost/tools/build/src/build\generators.jam:1056: in try-one-generator from module generators M:/data/boost/boost/tools/build/src/build\generators.jam:1294: in construct-really from module generators M:/data/boost/boost/tools/build/src/build\generators.jam:1378: in generators.construct from module generators M:/data/boost/boost/tools/build/src/build\targets.jam:1553: in construct from module object(typed-target)@19839 M:/data/boost/boost/tools/build/src/build\targets.jam:1353: in class(a)basic-target.generate from module object(typed-target)@19839 M:/data/boost/boost/tools/build/src/build\targets.jam:774: in generate-really from module object(main-target)@148055 M:/data/boost/boost/tools/build/src/build\targets.jam:746: in class(a)main-target.generate from module object(main-target)@148055 M:/data/boost/boost/tools/build/src/build\targets.jam:895: in targets.generate-from-reference from module targets M:/data/boost/boost/tools/build/src/build\targets.jam:1266: in generate-dependencies from module object(alias-target-class)@19840 M:/data/boost/boost/tools/build/src/build\targets.jam:1323: in class(a)basic-target.generate from module object(alias-target-class)@19840 M:/data/boost/boost/tools/build/src/build\targets.jam:774: in generate-really from module object(main-target)@148056 M:/data/boost/boost/tools/build/src/build\targets.jam:746: in class(a)main-target.generate from module object(main-target)@148056 M:/data/boost/boost/tools/build/src/build\targets.jam:272: in class(a)project-target.generate from module object(project-target)@19754 M:/data/boost/boost/tools/build/src/build\targets.jam:272: in class(a)project-target.generate from module object(project-target)@2060 M:/data/boost/boost/tools/build/src\build-system.jam:710: in load from module build-system M:\data\boost\boost\tools\build\src/kernel\modules.jam:295: in import from module modules M:\data\boost\boost\tools\build\src/kernel/bootstrap.jam:139: in boost-build from module M:\data\boost\boost\boost-build.jam:17: in module scope from module Anyone any ideas? Thanks, John.

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[Experimental Boost.DI] [v1.0.0 released] [Looking for a Review Manager] Your C+14 Dependency Injection library with no overhead and compile time creation guarantee!
by Krzysztof Jusiak 27 Feb '16

27 Feb '16

Dear Boosters, I have just released version 1.0.0 of experimental Boost.DI library. Your C++14 header only Dependency Injection library with no dependencies. Library entered Boost Formal Review Queue some time ago and right now, IMHO, is ready to be reviewed. http://www.boost.org/community/review_schedule.html Therefore, I'm looking for a Review Manager, so if you think that Boost.DI is good enough to be reviewed and you would like to help with it, please let me know. Thank you! In the mean time check out the library yourself online! http://boost-experimental.github.io/di/examples/index.html Or read the interactive documentation... http://boost-experimental.github.io/di Or check out the source code... https://github.com/boost-experimental/di Why Boost.DI? * Boost.DI has none or minimal run-time overhead * Boost.DI compiles fast / Faster than Java-Dagger2! * Boost.DI gives short diagnostic messages * Boost.DI is non-intrusive * Boost.DI reduces boilerplate code * Boost.DI reduces testing effort * Boost.DI gives better control of what and how is created * Boost.DI gives better understanding about objects hierarchy Read more why here -> http://boost-experimental.github.io/di/index.html Any feedback is more than welcome! Cheers, Kris

9 34

GSOC-2016
by Abhimanyu Shekhawat 27 Feb '16

27 Feb '16

Hi there ! I am Abhimanyu Shekhawat, a sophomore perusing B.E(Hons)Computer Science, Birla Institute of Technology & Science, Pilani - Goa,India. I would like to take part in GSOC Programme 2016 with Boost Community. Actually I am very excited about contributing to open source projects and I already have experiences with some of the college based projects till now.I feel that being able to work in open source community will not only expose me to new learning avenues but will also give me a chance to contribute to the a much larger community. As far as my background is concerned,I have taken a course on Discreet Mathematics and currently perusing a rigorous Algorithm and Data structure course. Also I have got an intermediate level of skill set in C++,C,Java,Android and Mysql while a basic understanding of python. I hope that my skills and enthusiasm will prove an asset to the community.So I will be grateful if you can get me started Thank you :D

3 2

[hana] missing .gitattributes
by Steven Watanabe 26 Feb '16

26 Feb '16

AMDG I just noticed that all the files for hana had \n line endings in my working copy. To fix this I had to copy .gitattributes from the superproject. (Or am I just using git wrong) In Christ, Steven Watanabe

3 5

[log][thread][teeks][igaztanaga] Log & Thread tests failing on MSVC & MinGW
by Andrey Semashev 26 Feb '16

26 Feb '16

Hi, I can see lots of Boost.Log tests are failing on igaztanaga and teeks99-08 testers [1], while the error logs are non-descriptive (show a successful compilation). For some tests the links in the table refer to successful compilation of Boost.Thread, which I can see is failing on the same testers the same way [2]. What's interesting, teeks99-09 testers are green for both libraries. Is there a known problem with Boost.Thread on Windows? Or with these particular testers? If not, is it possible to see the actual failure logs? PS: Disregard the MSVC-7.1 and gcc 3.4 columns. These old compilers I don't expect to work. [1] http://www.boost.org/development/tests/develop/developer/log.html [2] http://www.boost.org/development/tests/develop/developer/thread.html

1 0

toml parser for boost::property_tree
by Auer, Jens 26 Feb '16

26 Feb '16

Hi, is somebody working (or has been) on a property_tree parser for toml (https://github.com/toml-lang/toml)? if not I would give it a try. It looks like a project with reasonable for a single person, but complex enough to involve some interesting components, e.g. boost::spirit. Cheers, Jens -- Jens Auer | CGI | Software-Engineer CGI (Germany) GmbH & Co. KG Rheinstraße 95 | 64295 Darmstadt | Germany T: +49 6151 36860 154 jens.auer(a)cgi.com<mailto:jens.auer@cgi.com> Unsere Pflichtangaben gemäß § 35a GmbHG / §§ 161, 125a HGB finden Sie unter de.cgi.com/pflichtangaben<http://de.cgi.com/pflichtangaben>. CONFIDENTIALITY NOTICE: Proprietary/Confidential information belonging to CGI Group Inc. and its affiliates may be contained in this message. If you are not a recipient indicated or intended in this message (or responsible for delivery of this message to such person), or you think for any reason that this message may have been addressed to you in error, you may not use or copy or deliver this message to anyone else. In such case, you should destroy this message and are asked to notify the sender by reply e-mail.

1 0