May 2015 - Boost - lists.preview.boost.org

[test] Fwd: [Boost-testing] All test runners (windows and linux) crashing
by Rene Rivera 29 May '15

29 May '15

Boost Test developers please fix ASAP. ---------- Forwarded message ---------- From: Tom Kent <lists(a)teeks99.com> Date: Thu, May 28, 2015 at 8:26 PM Subject: Re: [Boost-testing] All test runners (windows and linux) crashing To: Running Boost regression tests <boost-testing(a)lists.boost.org>, Boost Developers List <boost(a)lists.boost.org> On Thu, May 28, 2015 at 6:24 PM, Tom Kent <lists(a)teeks99.com> wrote: > All my test runners are quickly crashing during each run...here's the end > of the output in my results/bjam.log file: > > boost-test(RUN) "test/doc_boost_test_macro1" : > "libs/test/doc/examples/boost_test_macro1.cpp" > boost-test(RUN_FAIL) "test/doc_boost_test_macro2" : > "libs/test/doc/examples/boost_test_macro2.cpp" > boost-test(RUN_FAIL) "test/doc_boost_test_macro3" : > "libs/test/doc/examples/boost_test_macro3.cpp" > error: at D:/t08/c/boost_bb/src/kernel\modules.jam:107 > error: Unable to find file or target named > error: '../doc/examples/test_float_01.cpp' > error: referred to from project at > error: '../libs/test/test' > > Any thoughts? > Tom > I should have specified, that is on the develop branch. Master seems fine. _______________________________________________ Boost-Testing mailing list Boost-Testing(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-testing -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

2 2

All test runners (windows and linux) crashing
by Tom Kent 29 May '15

29 May '15

All my test runners are quickly crashing during each run...here's the end of the output in my results/bjam.log file: boost-test(RUN) "test/doc_boost_test_macro1" : "libs/test/doc/examples/boost_test_macro1.cpp" boost-test(RUN_FAIL) "test/doc_boost_test_macro2" : "libs/test/doc/examples/boost_test_macro2.cpp" boost-test(RUN_FAIL) "test/doc_boost_test_macro3" : "libs/test/doc/examples/boost_test_macro3.cpp" error: at D:/t08/c/boost_bb/src/kernel\modules.jam:107 error: Unable to find file or target named error: '../doc/examples/test_float_01.cpp' error: referred to from project at error: '../libs/test/test' Any thoughts? Tom

1 1

[type_traits][units] migrating from ice_and
by Jürgen Hunold 28 May '15

28 May '15

Hi! I've noticed that boost/type_traits/detail/ice_or.hpp and boost/type_traits/detail/ice_and.hpp have been deprecated. Both headers are used as an implementation detail in boost/units/scaled_base_unit.hpp, now resulting in lots of warnings: In file included from .../boost/units/scaled_base_unit.hpp:20: .../boost/type_traits/detail/ice_or.hpp:17:10: warning: NOTE: Use of this header (ice_or.hpp) is deprecated [-W#pragma-messages] # pragma message("NOTE: Use of this header (ice_or.hpp) is deprecated") Question: Is there a known migration path from type_traits to what? MPL? Or am I better off copying both files to Boost.Units and be done? Yours, Jürgen -- * Dipl.-Math. Jürgen Hunold ! * voice: ++49 4257 300 ! Fährstraße 1 * fax : ++49 4257 300 ! 31609 Balge/Sebbenhausen * jhunold(a)gmx.eu ! Germany

3 4

[testing][teeks] MSVC-14 errors about MSPDB140.DLL
by Andrey Semashev 27 May '15

27 May '15

Hi, All tests for Boost.Log (and I suspect any other built libraries) on MSVC-14 are failing because of this error: LINK : fatal error LNK1101: incorrect MSPDB140.DLL version; recheck installation of this product See here for example: http://www.boost.org/development/tests/develop/developer/output/teeks99-08f… Could this be fixed?

4 7

[typeof] Weird VC++ compiler bug
by Edward Diener 27 May '15

27 May '15

I discovered a strange VC++ bug using Boost.typeof. I am not posting this to rag VC++ but wondering if there is some known workaround in Boost or in Boost.config. #include <boost/typeof/typeof.hpp> template <class T> struct dereference { typedef BOOST_TYPEOF_TPL(*T()) type; }; int main() { } Compiling this with VC++12 gives: test_vc_type_of_indirection.cpp(6) : error C2100: illegal indirection test_vc_type_of_indirection.cpp(7) : see reference to class template instantiation 'dereference<T>' being compiled Notice that I am not even instantiating 'dereference'. But if I write: #include <boost/typeof/typeof.hpp> template <class T> struct dereference { void afunction() { typedef BOOST_TYPEOF_TPL(*T()) type; } }; int main() { } all is well, for all the good it does me. BOOST_TYPEOF_TPL(*T()) expands to: typename boost::type_of::msvc_typeid_wrapper<sizeof(*boost::type_of::encode_start(*T()))>::type and if I substitute this directly the same results occur. I can report this to the VC++ bug tracker but wanted to see if this is a known problem with VC++ in Boost, some weird error for which maybe Boost has some workaround syntax.

6 13

Fwd: Binary Region Differentials
by Kenneth Adam Miller 27 May '15

27 May '15

Suppose I have a rather huge binary region. Transferring it by any means is an expensive operation. But changes to it will only be some fraction at worst case as large as the binary region itself, but in practice will typically be regional byte blobs, mostly not more than a single kilobyte long.. Is there any data structure that already handles this, where I could say, have every instance start off from the original binary region, and calculate what any other instance of that data structure has by "applicating the deltas"?

3 4

svn.boost.org SSL cert errro
by Olaf van der Spek 26 May '15

26 May '15

Hi, The certificatie of svn.boost.org has expired (two weeks ago).. -- Olaf

10 19

[branch master] add library to regression tests
by Oliver Kowalke 26 May '15

26 May '15

Hello, could you please add boost.coroutine2 to the regression tests of branch master?! best regards, Oliver

1 0

Aho - Corasick String Search (for searching multiple patterns) Interface
by meghana madhyastha 26 May '15

26 May '15

Hi, In some of my previous mails I had suggested that the Rabin Karp and Aho - Corasick string search algorithms be implemented as a part of the Boost algorithm library. This is primarily because these algorithms perform well for searching for multiple patterns. The Aho - Corasick algorithm works by building a trie (a tree with each node corresponding to an ASCII character) of the patterns strings and traversing the trie to search for the pattern in a given text. Additionally, the Aho - Corasick introduced the concept of "failure pointer/failure node" which is the node to be traversed when there is a mismatch. For more information: http://en.wikipedia.org/wiki/Aho%E2%80%93Corasick_string_matching_algorithm The interface I propose is as follows. 1. The input of the patterns should be strings within a *container*. This is because these algorithms are primarily used for multiple pattern searching. The user can input pointers/iterators to the first and last pattern . The final output which is returned is a container with each pattern and a iterator/pointer to their occurrences (There are multiple patterns so just returning an iterator/pointer to where the patterns first occurs in the pattern will not suffice). 2. Just like the previous string searching algorithms that have been implemented in Boost, there can be an object based interface as well as a procedure based interface. In the object based interface, the trie is constructed and the failure nodes are computed in the constructor (while creating the object). The user can then search the text using the operator(). template <typename patIter> class aho_corasick { public: aho_corasick(patIter first, patIter last): pat_first(first), pat_last(last), head(std::shared_ptr<trie_node>(new trie_node)) { //first and last are pointers/iterators to the first and last patterns in the container gotoFn(head); failureFn(head); } ~aho_corasick () {}; template <typename corpusIter> corpusIter operator ()(corpusIter corpus_first, corpusIter corpus_last) //Note: using the same notation as used in the other search algorithms. Corpus- refers to the text to be searched. I've implemented this and would like to get feedback/suggestions on the code as well as the interface. Where should I put up the code for it to be reviewed ? Thanks, Meghana

1 0

boost [vmd]: configuration issue in Jamfile.v2 for Oracle Solaris Studio compiler
by Aparna Kumta 26 May '15

26 May '15

I am looking at my test run for vmd in develop branch. http://www.boost.org/development/tests/develop/developer/vmd.html under SunOS. My tests are run with cxxflags="-compat=5 -library=stlport4" as configured in user-config.jam An example of a test, http://www.boost.org/development/tests/develop/developer/output/oracle-spar… The test fails as follows: "CC" -std=c++0x -std=c++11 -compat=5 -library=stlport4 -xO4 -mt -erroff=%none -m32 -KPIC -DBOOST_ALL_NO_LIB=1 -DNDEBUG -I".." -c -o "/export/home/sstrunk-tester/boost_regression/boost_sparc-S2_stlport4/results/boost/bin.v2/libs/vmd/test/test_after_identifier_elem.test/sun-stlport4/release/threading-multi/test_after_identifier_elem.o" "../libs/vmd/test/test_after_identifier_elem.cpp" CC: -compat=5 can not be used with -std CC: -library=stlport4 cannot be used with -std=c++11 If I compile the test manually without '-std=c++0x -std=c++11', the test compiles OK. %CC -compat=5 -library=stlport4 -xO4 -mt -erroff=%none -m64 -KPIC -DBOOST_AL0%L_NO_LIB=1 -DNDEBUG -I.. -c -o ./test_after_identifier_elem.o ../libs/vmd/test/test_after_identifier_elem.cpp % It looks like boost_root/libs/vmd/test/Jamfile.v2 needs to be modified for this compiler. Any ideas on how this can be done? Thanks, Aparna

2 3

boost::bind C2664 error with two non-const references
by Nicolas FRANCOIS 25 May '15

25 May '15

Hi, Relatively to this thread http://lists.boost.org/Archives/boost/2015/03/220930.php and this correcting commit 42b5cef177603328ead66bc6a98a3067aebc433d, I still have errors using boost::bind. #include <boost/bind.hpp> #include <boost/function.hpp> struct A { void f(int&, std::vector<int*>&); }; int main(){ A a; auto f = boost::bind(&A:f, &a, _1, _2); } results in error C2664: cannot convert from 'const std::vector<int*> &' to 'std::vector<int*> &' Defining BOOST_NO_CXX11_RVALUE_REFERENCES solves the issue for now. Nicolas FRANCOIS Software Department L-ACOUSTICS Tel : +33 (0) 1 69 63 23 90 Fax : +33 (0) 1 69 63 69 64 www.l-acoustics.com<http://www.l-acoustics.com/> Please consider the environment before printing this email.

2 7

Environment Variables Library?
by Michael Ainsworth 24 May '15

24 May '15

StackOverflow regarding the (non) standardisation of the "setenv" function, does Boost provide a library to interact with environment variables? http://stackoverflow.com/questions/30292642/c-standard-library-stdsetenv-vs… Michael

10 34

[testing][CrystaX.NET] Missing header
by Andrey Semashev 23 May '15

23 May '15

Hi, Many of the CrystaX.NET testers fail to compile tests because of this error: fatal error: crystax/google/sys/select.h: No such file or directory See here for example: http://www.boost.org/development/tests/develop/developer/CrystaX-NET-apilev… Could this be fixed?

2 1

boostdep documentation?
by Robert Ramey 22 May '15

22 May '15

I am interesting in taking a look at boostdep. I see the code in tools/... but I don't see any documentation. Is there any? will there be in the future? Robert Ramey

2 3

Re: [boost] [Better Enums] Interest in/feedback on C++11 enums library
by Anton Bachin 22 May '15

22 May '15

I've been keeping away because I am doing a ton of work on the library, and I don't want to attract too much attention until the work is ready, since there are lots of changes. But, I think I should reply, and I will also give a brief update of the progress at the end of the message. > I suspect this code: > > Depth depth = default_<Depth>(); > > could be made to look like this: > > Depth depth = _default; > > > ie all enums have a constructor that takes a default_t type. The > constructor then calls default_<T>(). > Or something like that. And then change the names to get > > Depth depth = default_; // calls default_impl<T>(); That’s a good idea. I hadn't thought of such a constructor. I will try it out, but I am not sure that it would belong directly in the library, if that's what you mean. It's not clear where one should stop. Should there also be an "invalid" constructor for projects that have such a notion? Are there other special values we can't predict? Perhaps this could be achieved with some kind of extension facility. I will eventually be adding either support for subclassing, or extra macros, or some kind of template-based extensibility. To the other commenters: thanks :) As for progress: there are substantial improvements. - The entire interface is now constexpr, including string functions and iterators. - I ported the interface to C++98, though it still requires __VA_ARGS__. This makes the topic of this message inaccurate. Should I start a new thread for the new version when it's up? - The C++98 conversion means that, in theory, the library should work on MSVC down to VS2005. I will be testing that when I get my new notebook in a few days. If successful, Better Enums will be compatible with the 3 major compiler families. - Eliminated all weak symbols, leaving only standard C++. Some may be brought back later for optimization, but they are no longer required. - When compiling for C++11, there are no more implicit conversions to integers. - The library is now a single header file, containing both the C++11 version and the C++98 port, and all helper macros. - The documentation is getting a major improvement, so please don't look now. The all-constexpr version is unfortunately noticeably slower to compile. The performance test that was previously two times faster than including iostream is now twice as slow, but I can mitigate this with some combination of opt-in and optimization. Anton

1 0

[build][test][gsoc] question about compiling tests with multiple compile params using b2
by Damian Vicino 22 May '15

22 May '15

Hi, I’m working in the safe_float library for the GSOC. For testing I’m using the boost.test library and for building I’m using b2. The implementation have several pieces that are implemented in two flavours, one for compilers supporting FLOAT_ENV and one for those not supporting it. (this is a C++11 feature missed in at least clang and gcc compilers) Right now, the implementation is selected with an #ifdef and I #define them with a -D parameter. My config file for test is: using testing ; lib boost_unit_test_framework ; unit-test test : main-test.cpp [ glob *_test.cpp ] boost_unit_test_framework ; I guess I can generate 2 different executables using 2 targets, duplicating last line and adding something to tell it to pass -DFENV_AVAILABLE, but I couldn’t find how to do that. Having 2 executables for the tests and running them both will provide testing for both compilation paths (when using a compiler supporting FENV). Also, I’m wondering if B2 has the inteligence detect and pass a parameter when using a compiler supporting FENV. Is there any common approach for these situations where conditionally compiling based on a c++ feature support? In the case a Boost.Build needs to define a test for detecting if the compiler supports the feature (autoconf-like) it can be tested compiling a one-liner file: test.fenv.cpp #pragma STDC FENV_ACCESS ON When compiled: clang++ -c test.fenv.cpp test.clang.cpp:1:14: warning: pragma STDC FENV_ACCESS ON is not supported, ignoring pragma [-Wunknown-pragmas] #pragma STDC FENV_ACCESS ON The warning means the feature is not supported. Thanks for any guidance in this area, I’m pretty newbie with the b2 system. Best regards, Damian

2 1

[Better Enums] Interest in/feedback on C++11 enums library
by Anton Bachin 21 May '15

21 May '15

Hello, I’ve just released an enum library that takes advantage of constexpr functions and literal types to provide a nice declaration syntax and decent feature set: https://github.com/aantron/better-enums <https://github.com/aantron/better-enums> I’d like to get feedback on it from the experienced developers here at Boost. Is this approach useful? Are any major features missing? Would this be an interesting candidate for enums in Boost? I am very willing to do further development on this project. The library's basic features are string conversions, value and name listing, some type safety, and a declaration syntax that is based on built-in enums and is easy to learn and use. A much more "advanced” feature is that the generated class is a literal type, and almost everything is constexpr. Here is a simple example, that takes advantage of this, of a compile-time encoding of project policy: https://github.com/aantron/better-enums/blob/master/example/6-traits.cc <https://github.com/aantron/better-enums/blob/master/example/6-traits.cc> . Once I make the iterators constexpr as well, by providing a way to increment them other than mutation (++), it will be easy to write rather involved compile-time algorithms that process Better Enums declarations. Here is an example of a whole bunch of simple compile-time processing already possible: https://github.com/aantron/better-enums/blob/master/example/4-constexpr.cc <https://github.com/aantron/better-enums/blob/master/example/4-constexpr.cc> . Some of that could be useful when C++ declarations are generated by script. The library is all standard C++11 (to the best of my knowledge), except for the usage of weak symbols for some generated constexpr static arrays. I have tested it successfully on clang and g++, but I would need help getting access to more compilers. I believe weak symbols are not a problem for MSVC, but I still don’t believe the library will compile on MSVC since I don’t think MSVC supports enough of C++11 yet. Performance is what I would call excellent. I compared compilation times of these two files to each other: https://github.com/aantron/better-enums/blob/master/test/performance/4-decl… <https://github.com/aantron/better-enums/blob/master/test/performance/4-decl…> https://github.com/aantron/better-enums/blob/master/test/performance/5-iost… <https://github.com/aantron/better-enums/blob/master/test/performance/5-iost…> The first file includes enum.h and declares a bunch of enums, and the second merely includes iostream. On my machine, clang compiled all those enums in about half the time it took to process iostream. g++ was faster on iostream, but only slightly. Using a lot of compile-time expressions would have additional cost, but it has been too small to measure for “realistic” examples from my own usage. I haven’t yet made an example that repeatedly deals with a very large enum at compile time to properly measure that impact. I’ve also explored an alternative interface where the constexpr properties provided by the library are in a traits class parametrized by a normal C++11 enum class, but the interface seemed too verbose. There is also a bitset type that has a very slightly nicer interface than std::bitset for usage with enums, but I didn’t think the improvement was worth the user’s learning effort. I can put these in branches if there is interest, however. Please let me know what you think. Best, Anton

5 4

[BOOST_FOREACH] Problem to iterate on a non-copyable container...
by nico 21 May '15

21 May '15

I'm not sure of the title, because I'm not sure the issue comes from the "copyablility" of my container. I tryied quite everything but I can't get rid of this error. Here is a simplified version of my code (please do not challenge the class design, I really would like to keep the end-used syntax in the BOOST_FOREACH): template <typename T> class MyContainer { public: typedef typename std::vector<T>::iterator iterator; typedef typename std::vector<T>::const_iterator const_iterator; MyContainer(std::vector<T>& vec, boost::mutex& mutex) : m_vector(vec), m_lock(mutex) { } iterator begin() { return m_vector.begin(); } const_iterator begin() const { return m_vector.begin(); } iterator end() { return m_vector.end(); } const_iterator end() const { return m_vector.end(); } private: std::vector<T>& m_vector; boost::lock_guard<boost::mutex> m_lock; }; template <typename T> struct GetContainer { GetContainer(std::vector<T>& vec, boost::mutex& mutex) : m_vector(vec), m_mutex(mutex) { } MyContainer<T> Get() { return MyContainer<T>(m_vector, m_mutex); } std::vector<T>& m_vector; boost::mutex& m_mutex; }; int main() { std::vector<int> v; v.push_back(1); v.push_back(2); boost::mutex m; GetContainer<int> getter(v, m); BOOST_FOREACH(int i, getter.Get()) { std::cout << i << std::endl; } return 0; } The compiler complains about not having a copy constructor for MyContainer<int>::MyContainer(const MyContainer<int>&) I also have : error: no matching function for call to ‘MyContainer<int>::MyContainer(boost::foreach_detail_::rvalue_probe<const MyContainer<int> >::value_type)’ I follow the extensibility tips: http://www.boost.org/doc/libs/1_58_0/doc/html/foreach/extensibility.html#fo… But, making MyContainer<T> : private boost::noncopyable doesn't solve the issue. Nor defining the function boost_foreach_is_noncopyable or specializing the template struct is_noncopyable for MyContainer<int> (in fact, how would I specialize this template for a template type ?) Last "tip": If I remove the mutex and the lock from everywhere (I just pass the vector to GetContainer and to MyContainer<T>, it works. But it doesn't work if I make MyContainer<T> : private boost::noncopyable (I expected it should, so I'm not sure my problem is with BOOST_FOREACH, but maybe because I return a copy of MyContainer with my getter ?) I thank you if you read me until here, and thanks in advance for help.

3 4

What does "xml this : this.qbk" do?
by Peter Dimov 21 May '15

21 May '15

Documentation Jamfiles often contain a line like xml core : core.qbk ; What does this line do? Is "xml" a rule? I haven't been able to find it anywhere.

2 1

Questions about upcoming review of Boost.AFIO
by Niall Douglas 21 May '15

21 May '15

Dear list, Ahmed has volunteered to review manage AFIO (thanks Ahmed!), however I wanted to get the list's feedback on some things first. 1. After collecting feedback at C++ Now from members of WG21 on the shape and preferred future of a race free Filesystem TS, the next iteration of AFIO will have a radically different API consisting of the form: std::vector<afio::future<T>> afio::batch(...) afio::future<T> afio::async_io_handle::operation(inputs) noexcept(is_nothrow_move_constructible<T>) T afio::io_handle::operation(inputs) T afio::io_handle::operation(error_code &ec, inputs) The internal engine is the same very well tested code, just the API is very different from before. The current API was forced by VS2010's limitations and the lack of constexpr in MSVC - now VS2015 RTM has C++ 11 constexpr, I can adopt the custom future based API I always originally wanted. This new API will require C++ 14 in the compiler. Question: Given the API will so radically change, is now the time for a community review? Do note that APIBind allows me to support the existing API and the new API concurrently without issue. 2. AFIO requires APIBind which is a separate library. APIBind is not yet in the review queue and it is pending me writing up its documentation and a more useful unit test suite. Is this a problem? Do note that you the user of AFIO will never need to know about APIBind, it is entirely an internal implementation detail. Comments appreciated. Niall -- ned Productions Limited Consulting http://www.nedproductions.biz/ http://ie.linkedin.com/in/nialldouglas/

8 10

More cool free github tooling: https://reviewable.io/
by Niall Douglas 21 May '15

21 May '15

Dear list, I'm not sure about other libraries, but in Boost.Thread Vicente the primary maintainer does the lion's share of dealing with pull requests but he occasionally needs someone else to review a patchset or a pull request before it can be merged. Github's facilities for this are okay - you can comment per line of a pull request, and overall. It works, though one wishes for something more gerrit like. So enter a new free tool with github integration: https://reviewable.io/. One click install into your github project. You now gain an alternative UI for pull requests, one which is much better than the default Github UI, specifically: * Per file review gating like gerrit * Can publish a group of per-line comments as a single thing (and just one email notification) * Doesn't hide deleted change history * Diffs are much better calculated and presented I've turned it on for AFIO. We'll see how it goes. Niall -- ned Productions Limited Consulting http://www.nedproductions.biz/ http://ie.linkedin.com/in/nialldouglas/

1 0

Some statistics about the C++ 11/14 mandatory Boost libraries
by Niall Douglas 21 May '15

21 May '15

Tomorrow at 11am after Eric's talk I'll be presenting at C++ Now a review of the upcoming C++ 11/14 mandatory Boost libraries. I looked at fifteen libraries and decided ten were worth further investigation. I'm sure you all remember my colour coded ranking of those ten libraries by "nearness" to entering Boost: https://goo.gl/6l1KiH I sadly only have time to review four of those libraries during my talk, but one (APIBind) enables an alternative Boost 2.0 approach and I will spend 45 mins on that library alone. And here is my alternative Boost 2.0 vision: Boost 2.0 is a alternative distro of modular standalone Boost libraries which can be each downloaded separately. Each has contemporary per commit CI testing and is nightly dashboarded by quality score by a web service under the 19 quality score headings listed at https://svn.boost.org/trac/boost/wiki/BestPracticeHandbook (still unfinished, but nearly there). APIBind allows the library end user to dependency inject what dependencies that library uses. This allows a Boost library, in a single codebase, to be part of both the monolithic Boost 1.x distro and to be modular and standalone and part of the Boost 2.x distro. Motivated library maintainers port their Boost 1.x library to the APIBind platform, and therefore can be part of both 1.x and 2.x distros if they want. Those libraries not ported to APIBind remain in the 1.x distro, which I would assume will gradually fade into obsolescence over time. This makes sense, as if a maintainer is not motivated to do the port then it seems proper that library should gracefully deprecate. There is some empirical data supporting the inevitability of this alternative vision of Boost 2.0. Of the ten libraries I examined in any detail: * Just 1.5 libraries have any dependencies on Boost headers at all (the 0.5 is because that library is currently removing its Boost dependencies). * Just 3 libraries can use Boost.Test. * Just 3 libraries use Boost Docs. * Just 2 libraries require using Boost.Build. The rest are header only, or use cmake. * Just 6 libraries use Travis/Appveyor for free CI testing on Linux, OS X and Windows. * Just 3 libraries use valgrind as part of their unit testing (two are mine!). * Just 3 libraries use coveralls for coverage reporting (two are mine!). Personally speaking, I think the new library authors are overwhelmingly voting for a complete break with Boost 1.x. It makes no sense to bundle these new libraries into a 1.x monolithic distro when they have no dependencies on Boost. I believe now is the time we start establishing the infrastructure to shape the new Boost 2.0 distro instead of wasting resources on trying to refactor the 1.x distro. APIBind is there for maintainers wanting to be part of both distros. Let's make a clean break. Niall -- ned Productions Limited Consulting http://www.nedproductions.biz/ http://ie.linkedin.com/in/nialldouglas/

28 133

Deprecation Policy
by Rob Stewart 21 May '15

21 May '15

Some Boost libraries are unmaintained, some are under-maintained, and others have been replaced by newer libraries or by the Standard Library. Boost needs to decide whether to deprecate such libraries, and if so, how and when to do it. Please consider my initial thoughts below and provide ideas on such a policy. I will try to capture your ideas and create a policy statement for later review. It would seem obvious that unmaintained libraries should be deprecated, but a library that works, even if it has some known bugs, doesn't grow worse over time. Thus, if an unmaintained library was included in one Boost release, continuing to include it is no worse than before. That implies that deprecating Unmaintained libraries is not a given. Another issue is deciding when a library is unmaintained. Boost prefers that library authors and maintainers seek a replacement when no longer able to provide maintenance. Unfortunately, that doesn't always happen. Thus, establishing criteria by which to judge a library as unmaintained is warranted. Many continue to use C++03 and benefit from the presence of libraries that only support that language. I think it a non-starter to suggest that a library is unmaintained, or under-maintained, because it hasn't been updated to use C++11/14. Indeed, a replacement library may be the better way forward, while the old library might remain in Boost releases. Some have suggested that libraries with Standard Library equivalents be considered deprecated. Note that such libraries provide equivalent or similar functionality for older compilers, so I think that they should be treated the same as C++03-only libraries. Libraries that have superior replacements in Boost releases seem like obvious candidates for deprecation. There is precedent for that: Boost.Signals was deprecated in favor of Boost.Signals2. There are some likely libraries in this category, such as Boost.Lambda. Once we reach consensus on how to identify libraries to deprecate, we then must decide on the process. How long should a deprecated library be released before it is removed from Boost releases? How do we mark deprecated libraries? What do we do with deprecated libraries that have been removed from Boost releases? ___ Rob (Sent from my portable computation engine)

12 33

[preprocessor] Link to Boostpro site for introduction to preprocessor metaprogramming
by Edward Diener 20 May '15

20 May '15

The preprocessor documentation has a link to the Boostpro site which had an html version of the Appendix A of "C++ Template Metaprogramming" by Abrahams and Gurtovoy. Appendix A is "An Introduction to Preprocessor Metaprogramming", which is all about Boost PP. Alas Boostpro is no more and the link in the preprocessor documentation goes nowhere. I can remove the link and any notice of the introduction. But If either David Abrahams or Aleksey Gurtovoy are still around it would be nice to get the html pages which existed before and incorporate them into the Boost PP docs. Does anyone know how to contact either of them ? I can try their addresses in maintainers.txt but I do not want to directly encroach on their privacy if there is a better way.

2 4

Interest in non-intrusive signal/slot lib?
by Emil Dotchevski 20 May '15

20 May '15

Hello, I realize that Boost has Signals library already, but I've implemented a non-intrusive one which approaches the problem differently, and I'm pretty sure that there is no overlap between the two. It turned out more generic than I originally anticipated, so I thought I'd ask if others would find it useful as well. Specifically I was motivated by wanting to use Qt without MOCing. I asked the Qt community if that was possible which generated several rather annoyed negative responses. :) The issue is that while in Qt it's possible to use any function as a Slot, to define a new Qt signal for an existing Qt type one needs to derive from the Qt type, define the signal (as a member function) and do the MOC dance -- which I wanted to avoid. The result is a small, non-intrusive signals/slots library that allows objects of any type to be used as signal emitters, e.g. one of the included examples shows how signals can be emitted by a Windows HWND object. Documentation and source code released under the Boost license can be found here: http://www.revergestudios.com/boost-synapse/. Thanks, Emil P.S. Thanks to Peter Dimov for his feedback and for coming up with the name Synapse. :)

9 48