November 2012 - Boost - lists.preview.boost.org

[boost::context] reusing stacks
by Valentin Milea 27 Nov '12

27 Nov '12

Hi, I'm working on a tiny coroutine library based on boost::context. For performance reasons I'd rather keep a pool of stacks instead allocating/deallocating every time. Is it legal to reuse a stack for a different context? namespace ctx = boost::context; ctx::fcontext_t fcm, *fc; void f1(intptr_t) { std::cout << "f1" << std::endl; ctx::jump_fcontext(fc, &fcm, 0); } void f2(intptr_t) { std::cout << "f2" << std::endl; ctx::jump_fcontext(fc, &fcm, 0); } int main(int argc, char * argv[]) { ctx::guarded_stack_allocator alloc; std::size_t size = ctx::guarded_stack_allocator::default_stacksize(); void *sp = alloc.allocate(size); fc = ctx::make_fcontext(sp, size, f1); std::cout << "main: jump 1" << std::endl; ctx::jump_fcontext(&fcm, fc, 0); fc = ctx::make_fcontext(sp, size, f2); // legal? std::cout << "main: jump 2" << std::endl; ctx::jump_fcontext(&fcm, fc, 0); std::cout << "main: done" << std::endl; return 0; }

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[boost-mpl] -Wall -Werror issue
by Belcourt, Kenneth 27 Nov '12

27 Nov '12

Hi, This code generates sign / unsigned compare warning with -Wall, could this please be cleaned up? enum { n = # if defined(__EDG_VERSION__) aux::dependent_unsigned<T>::value > -1 # else sizeof(T) > -1 # endif }; It appears that sizeof(T) > -1 yields zero for EDG, Gcc and Clang so perhaps this is just older (unused) code? -- Noel Belcourt

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[math] boost::math::isfinite fails with --fast-math
by Gaetano Mendola 26 Nov '12

26 Nov '12

Hi all, I'm wandering if this is to be expected, the following code fails if compiled with --fast-math: //==================================================== #include <boost/math/special_functions/fpclassify.hpp> int main() { const float a = 0.0f/0.0f; assert(not boost::math::isfinite(a)); } //==================================================== Regards Gaetano Mendola

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gcc 4.4.3 + boost optional 1.40 crash
by Gaetano Mendola 26 Nov '12

26 Nov '12

Hi all, after banging my head for an entire day I come out with this test case showing a possible bug in gcc 4.4.3 or in boost optional, the test crashes with a pure virtual method called only if compiled only with -O1, -O2, -O3. The same code in another machine with gcc 4.7.2 and boost 1.49 works fine. Regards Gaetano Mendola #include <boost/optional.hpp> #include <boost/noncopyable.hpp> class B : boost::noncopyable { //if the noncopyable is removed works public: virtual size_t bar() const = 0; }; class D : public B { public: D() :theBar(foo(10)) { } virtual size_t bar() const { return theBar; } private: static size_t foo(const boost::optional<size_t> a) { if (a) { //if this is a.is_initialized() then it works return a.get(); } return 2; } const size_t theBar; }; class Foo { public: Foo(const B& b) :theBar(b.bar() * b.bar()) { } private: const size_t theBar; }; int main() { { //if this section is removed works D d; try { Foo myCompound(d); } catch(...) {} } { D d; try { Foo myCompound(d); } catch(...) {} } }

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[mpi] New dedicated mailing list for Boost.MPI discussions
by Matthias Troyer 25 Nov '12

25 Nov '12

Dear all, We have created a new sub list boost-mpi(a)lists.boost.org for discussion of Boost.MPI development. Those interested can visit http://lists.boost.org/mailman/listinfo.cgi/boost-mpi to sign up. Best regards Matthias

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[Numeric Conversion] Documentation Notes/Questions
by Dave Abrahams 25 Nov '12

25 Nov '12

* First thing to note: the documentation makes this library less approachable than it could be. In order to even begin, one has to bury onesself in terminology (the "Definitions" section). A super-quick "hello, world" example and a very short tutorial at the beginning would help a *lot*. numeric_cast is arguably the most generally-useful interface of the whole library and yet it's not even discussed until the end of the docs. * It's not clear what the purpose of abt(x) is. In expressions, "x" usually means its value. When you introduce a mechanism like this, it would be a good idea to explain why it's needed. Most places, the use of "abstract" just seems to complicate things: "A ulp is a quantity whose abstract magnitude" what's wrong with "A ulp is a quantity whose magnitude" ?? The end of the section on "Range and Precision" begins to explain why you want "abstract," but it takes the reader a long time to get to it. * are next() and prev() always well-defined? Seems to me that an unlimited precision rational number type might not have them. Is that type not numeric? * How do size, width, and density relate to unlimited precision rationals? I imagine: size = infinity width = infinity density = ? * This is slightly ambiguous: "This definition allows for a concise definition of subranged as given in the last section." "final section" would be clearer. A link would help too. * This is unclear: "Abstract intervals are easier to compare and overlap since only boundary values need to be considered." an example would help. How can one kind of thing be "easier to overlap" than another? * Precision has a very non-generic description, being different for types with density 1 and other types. It's hard to see what use such a concept has, and as far as Google can tell it is not used anywhere outside the Definitions section * Description of unsigned types, I think, is wrong: Notice that a numeric type, such as a C++ unsigned type, can define that any V does not overflow by always representing not V itself but the abstract value U = [ V % (abt(h)+1) ], which is always in range. Seems to me that the abstract values represented by an unsigned integer type are not the set of whole numbers, but the set of whole numbers modulo whatever-the-max+1-is. That's a well-defined mathematical abstraction, isn't it? Is there a problem with that, such as multiplication not working properly (I don't think so)? * There seems to be a contradiction here: If V >= abt(l) and V <= abt(h), V is representable (can be represented) in the type T ... Given an abstract value V represented in the type T as v, the roundoff error of the representation is the abstract difference: ( abt(v)-V). If V is not representable in type T, can you write formulae using its representation in type T? Given what I read later, maybe you should have just said "exactly representable" in the first phrase. * s/at most/less than/?: Because a correctly rounded representation is always one of adjacents of the abstract value being represented, the roundoff is guaranteed to be at most 1ulp. * s/cannot be represented/cannot be exactly represented/ ?: The integer number -1 can be exactly represented in Int, Real and Whole, but cannot be represented in Cardinal, yielding negative overflow. * Uh-oh: Floating to Floating conversions are defined only if N is representable; if it is not, the conversion has undefined behavior. in many places you've used "representable" to mean "exactly representable," but I can't believe you mean that here; it would imply most double=>float conversions have undefined behavior. What does this mean, anyway? If an abstract value can be "inexactly representable," aren't all abstract values representable if there's at least one abstract value that's exactly representable? Just convert to that and you're done. I think you need to give some serious thought to the definition of "representable." * s/then/so/: R(X) & R(Y) == R(X), then X->Y is not subranged. Thus, all values of type X are representable in the type Y. (b) Y->X: R(Y) & R(X) == R(Y), then Y->X is not subranged. Thus, all * What's the difference between a policy and a "parameter that defines the conversion" in It can optionally take some policies which can be used to customize its behavior. The Traits parameter is not a policy but the parameter that defines the conversion. ?? -- Dave Abrahams BoostPro Computing Software Development Training http://www.boostpro.com Clang/LLVM/EDG Compilers C++ Boost

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[Review] Review results for Coroutines
by Hartmut Kaiser 24 Nov '12

24 Nov '12

All, The review for the Coroutines library written by Oliver Kowalke started September 3rd 2012, and ended on September 12th 2012. I counted 7 votes, none of which were NO. All authors votes YES, some made additional requests. Overall, the verdict of the community was clear: Oliver Kowalke's Coroutines library is ACCEPTED The discussion was lively and it touched on several points. Design ------ The Coroutines library offers enormous potential for programming regimes such as communications software and embedded systems design. Oliver selected a sensible granularity for his design. This granularity allows for fine-tuning the implementations of cooperative scheduling mechanisms while avoiding the prohibitively heavy weight of preemptive scheduling that is found in POSIX and often in implementations of the C++11 thread support library. In particular, the separation of Coroutines from Context allows for porting to other systems with minimal effort and maximum reliability and code re-use. Some suggestion related to the API have been made during the review, most of which (if not all) have already been addressed. Oliver has a full list of things and works on integrating the suggestions. Here is a short list: - allow to specify the allocator to use for memory allocations inside the library - remove 'self' pointer and replace with TLS - add symmetric coroutines API - better support for generator functionality Naming ------ Some of the people participating in the discussions suggested not to use the abbreviated 'namespace coro', but to use the full 'namespace coroutines' instead. This again is not a precondition for acceptance. Documentation ------------- The consensus of almost everybody referring to the documentation was that it is terse but readable and sufficient. People suggested to integrate the docs of the old Coroutines library (written as an GSoC project by Giovanni P. Deretta) into the documentation of the reviewed library. I would like to thank all who participated in the discussions. Regards Hartmut --------------- http://www.cct.lsu.edu/~hkaiser http://stellar.cct.lsu.edu http://boost-spirit.com

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Re: [boost] Countertree
by Leo Goodstadt 23 Nov '12

23 Nov '12

> On Tue, 20 Nov 2012, Vadim Stadnik <vadimstdk(a)gmail.com> wrote: > > On Mon, Nov 19, 2012 at 9:02 PM, Leo Goodstadt <leo.goodstadt(a)llew.org.uk>wrote: > > 1) For counter trees, the median is just the N/2-th value in the > > counter tree, where K is the size of the tree. > > The Nth-percentile can be calculated similarly. > > A rolling median with a fixed size window requires there to be an > > insertion and deletion for each (most!) new value, so I am guessing > > it should run in O(N log K) time, where N = size of data, K = size of > > window > > > > IIUC, it is better to avoid modifying original data (size N), the rolling > window of size K can be represented by a multiset based on an augmented > tree. This method guarantees complexity of obtaining 1st median value for > O(K log K) operations, which is the cost of construction of the rolling > window, every subsequent median value can be obtained for O(log K) > operations, when the window rolls. This approach should be more efficient. > Oops. Careless editing made me mix up my Ks and Ns, hopeless confusing everyone. So given a large data set of size N and we want to calculate medians across a rolling window of size K, we only need to create a counter tree of size K (the window size). The median is the K/2 value in the tree. As you point out, the entire operation runs in O(N log K) time. All sensible approaches to calculating medians I can think of take O(N log K) time. The question comes down to what the constants are. The great advantage of a counter tree is that we are not limited to medians (the 50%ile value). We can collect for example, the values at 25%, 50%, and, 75%, and so on, at only marginally extra cost. I presume that most of the cost lies in balancing the tree after insertions/deletions and updating the counters. The only shortcut is the trivial optimisation that if the value entering the window is the same as the one being removed at the other end, then the median obviously stays the same. Leo

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[coroutine] update for intel/clang
by Oliver Kowalke 23 Nov '12

23 Nov '12

The lib compiles with gcc, intel, clang (bug fixed), msvc and mingw (statically linked) on Windows. The fixed version of boost.coroutine is available at: http://ok73.funpic.de/boost-coroutine.zip. The documentation is updated too: http://ok73.funpic.de/boost/libs/coroutine/doc/html/index.html Oliver

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Re: [boost] [website] bcp link broken
by Brian Wood 22 Nov '12

22 Nov '12

>>> bcp. Get taken nowhere. Any clues? TIA, >> >> Some googling found the page[*]. There, I read this: >> >> Copyright ? 2209 John Maddock >> >> Year 2209?! Great scott!!! Doc Emmett just called. He wants his DeLorean >> back. ;-) > > DeLorean? Man that's so last millenium :) > Maybe some are noticing a back to the future element in C++? -- Brian Ebenezer Enterprises http://webEbenezer.net (651) 251-9384

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[preprocessor] Maybe a improvement of BOOST_PP_IS_EMPTY
by Zhenghui Zhou 22 Nov '12

22 Nov '12

As I known, the undocument interface BOOST_PP_IS_EMPTY is not a general implementation to condider emptiness. There is a undefined behaviours when token concatenation return a invalid preprocessing token. Particularly, gcc restriction reports error. For example: #include <boost/preprocessor/ facilities/is_empty.hpp> BOOST_PP_IS_EMPTY() /* result: 1 */ BOOST_PP_IS_EMPTY(a) /* result: 0 */ BOOST_PP_IS_EMPTY(+a) /* error report here, for '+' cannot be pasted */ Here is a work around, it hasnot been tested enough, but does do under gcc. #define MY_IS_EMPTY(a) BOOST_PP_EQUAL(BOOST_PP_SEQ_ SIZE(MY_IS_EMPTY_II(MY_IS_EMPTY_I(a))), 2) #define MY_IS_EMPTY_I(a) (BOOST_PP_CAT(MY_IS_EMPTY_I_, BOOST_PP_SEQ_SIZE(a))) ) #define MY_IS_EMPTY_I_0 MY_IS_EMPTY_I_HELPER BOOST_PP_LPAREN() #define MY_IS_EMPTY_I_HELPER(a) )a( /* when a is empty, my may get more sequence elements of boost proprocessor */ #define MY_IS_EMPTY_II(a) BOOST_PP_CAT(MY_IS_EMPTY_II_, BOOST_PP_SEQ_SIZE(a)) ) #define MY_IS_EMPTY_II_1 ( #define MY_IS_EMPTY_II_2 ()( It uses a intermadiate result of BOOST_PP_SEQ_SIZE with wrong parameters, as: BOOST_PP_SEQ_SIZE(a) => 0 a ... I think it maybe better to allow any concatenation tokens in the language itselft. It's hard to avoid such thing when taking the preprocessor as a MPL. I just reported it on comp.std.c, https://groups.google.com/forum/#!topic/comp.std.c/7rgt8k6ILMM. There are more things and problems I did and I met. Hope for more response.

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[website] bcp link broken
by Eric Niebler 22 Nov '12

22 Nov '12

Go here: <http://www.boost.org/doc/tools.html>. Click on the link to bcp. Get taken nowhere. Any clues? TIA, -- Eric Niebler BoostPro Computing http://www.boostpro.com

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[dynamic_bitset] expression template?
by Ben Coates 21 Nov '12

21 Nov '12

dynamic_bitset currently allocates temporary vectors for most operations, and all the allocating and deallocating can easily dominate the running time for a program that makes heavy use of them. You can work around some of it with careful use of named temporaries around loops but some operations like intersection of 3 sets ( (a & b & c).any() ) result in a lot of unwanted copies and allocations. I've had good results converting it to use expression templates for intermediary operations, with the outcome of being able to do arbitrary non-resizing operations without allocating. Is there any interest in changing the boost version to do this?

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Should the clang, c++11 and libstdc++ configuration supported?
by Vicente J. Botet Escriba 21 Nov '12

21 Nov '12

Hi, clang compiler is not delivered with a C++11 standard library. When compiling on c++11 mode, some boost libraries (in particular, Boost.Thread, Boost.SmartPtr, Boost.Test) are expecting to have a C++11 standard library. This mean that the user needs to install the latest version of libc++. Could we state clearly in the release notes if the combination clang+ -std=c++11 + libstdc++ is not supported. Otherwise these libraries should update their code so that the user can use this combination. Best, Vicente

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[stl_ext_adv] comparison with Boost.Container and string algorithms
by Vadim Stadnik 21 Nov '12

21 Nov '12

Hi all, In response to the previously made suggestion, I have added to the documentation the comparison of new proposed STL containers with Boost.Container. Please let me know if some of my statements concerning Boost.Container are incorrect, I will update the documentation. >From a user perspective an augmented array based B+ tree of the new library can be regarded as a segmented vector that offers several more efficient operations than std::vector: logarithmic time insertion, erasure, splice and split. One such data structure can support interfaces of all C++03 standard sequences and associative containers. This is why new containers offer a higher level of uniformity and generalization of the C++ standard containers. Unlike std::vector, the new array based containers do not have the problem of exponential storage growth and manual shrinking storage to the optimal capacity. The comparison section also includes simple tests of performance. One test shows the advantage of the wide set of efficient operations of new containers. None of the C++ standard and Boost containers can outperform new containers in the test with just two operations: move an iterator to a specified position and then insert a new element. The other test shows that new containers have good locality of reference. In sequential processing they perform much better than containers using dynamically allocated data structures. String algorithms The new sequence container that implements the union of interfaces of std::vector, std::list and std::deque is particularly beneficial for string algorithms. A container, such as std_ext_adv::sequence<char>, efficiently supports all main editing string operations: cut, copy, paste, delete, find, replace, etc. In terms of computational complexity this new container provides general and equally efficient support for both copy and move semantics operations. The move semantics functions splice() and split() can be used to replace inefficient copy semantics functions insert() and erase() to achieve significant performance improvements. The examples section and code shows how to concatenate two strings and extract a sub-string in logarithmic time using the move semantics functions. These operations do not require that user algorithms count moved characters. This functionality and efficiency are not possible with linked lists and basic search trees. The efficient calculation of statistical parameters and numerical integration in logarithmic time are the other practically important applications of the new containers. They are discussed in the examples section. Project (source code and documentation): https://github.com/vstadnik/stl_ext_adv_review Documentation: http://dl.dropbox.com/u/51041088/stl_ext_adv_review/doc/index.html Regards, Vadim Stadnik

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Re: [boost] [Boost-build] [VxWorks] Updating boost/config/platform/vxworks.hpp for VxWorks 6.9
by Vicente J. Botet Escriba 20 Nov '12

20 Nov '12

Le 20/11/12 15:30, Brockamp, Peter a écrit : > Hello everybody, > > I'm new to the Boost.Build mailing list, so please forgive me any newbie > mistakes. I hope this is the right place for my post, if not please > redirect me to where it belongs! > I'm replied to the boost dev ML as most of the patches concern Boost.Config. > OK, some time ago I had to realize that the platform configuration for > VxWorks boost/config/platform/vxworks.hpp appears to be badly outdated > and doesn't work with the actual version 6.9. I started to modify this > platform header and after a while managed to get Boost compile and run > under VxWorks 6.9, at least as far as we use it here today. I could > offer to the community to update the existing header if this is desired > (I suppose it is). If so should I post the source code here or how to > proceed? Yep, a newbie question. You can start by creating a ticket on the Trac system https://svn.boost.org/trac/boost/newticket. You could add a patch associated with the ticket. > > My modifications surely aren't perfect/complete but it might be a fresh > start for this OS: > > - I have only tested it under RTP (Real Time Process) of VxWorks, not > DKM (Downloadable Kernel Module), due to lack of time. DKM has many > limitations compared to RTP, so this might cause problems! > > - Equally, due to time constraints, I tested GCC only, not the > diab-compiler, as we don't use it here. Same as above applies here, > problems might arise and I could not guarantee I might be able to fix > them. > > - And I tested x86 only, as we actually don't develop for ARM, etc. > > - I could test with V6.9 only, as we are not using the prior versions, > so maybe there will be other problems yet unknown. But at least I could > confirm that it is impossible to get Boost running under early versions > of VxWorks (V5.x and older). These versions are lacking a couple of > library functions required by Boost, they come with a library which is > partially non-ANSI-conforming (especially the STL) and the compiler (GCC > 2.96) is outdated beyond believe and lacks some functionality (mainly > template stuff) needed by Boost. So some OS-version checking scheme > would have to be added to vxworks.hpp, bailing out in case of obsolete, > unsupported versions. > > - A support guy from WRS (Wind River System) mentioned that they are > thinking of including Boost into their OS, so they might do some > adaption work in the future. But until now it doesn't appear to me > there's much activity from WRS, that's why I decided to offer what I > have done so far. > > - When compiling Boost for VxWorks I didn't use the build-system, as > VxWorks does a cross compile for the destination platform and I didn't > manage to figure out how to auto build this. Instead I manually pulled > all of Boost's files into a Workbench Project (Workbench is the eclipse > based IDE of VxWorks). So there would be some work left to get this up & > running as well. > > - My work is based mainly on modifying and supplementing most parts of > vxworks.hpp. Anyway, during the tests I did I stumbled upon some > problems in other files, e. g. caused by missing #ifdef's for VxWorks, > and even errors in a few of Boost's files, which I fixed as well. Should > all these fixes be posted here, or what's the right way to do it? > > > So, if you see some potential use in what I have done, despite the > incompleteness pictured above, please someone responsible mail me with > further instructions. > Best, Vicente

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Boost.Thread 1.52 vs 1.51 - g++ 4.7.2
by Jose 20 Nov '12

20 Nov '12

When including thread.hpp (1.52) I get the error below. Same setup but Boost 1.51 works ok. Does anybody know what is the issue ? thanks # g++ -c test.cpp In file included from /usr/include/boost/thread.hpp:24:0, from test.cpp:1: /usr/include/boost/thread/future.hpp:139:26: error: expected ‘;’ at end of member declaration /usr/include/boost/thread/future.hpp:139:32: error: ‘BOOST_THREAD_NOEXCEPT_OR_THROW’ does not name a type /usr/include/boost/thread/future.hpp:139:19: error: looser throw specifier for ‘virtual const char* boost::future_error::what() const’ In file included from /usr/include/boost/thread/exceptions.hpp:21:0, from /usr/include/boost/thread/pthread/thread_data.hpp:10, from /usr/include/boost/thread/thread.hpp:17, from /usr/include/boost/thread.hpp:13, from test.cpp:1: /usr/lib/gcc/x86_64-redhat-linux/4.7.2/../../../../include/c++/4.7.2/stdexcept:70:5: error: overriding ‘virtual const char* std::logic_error::what() const throw ()’

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Graph Algorithm Advice
by J Birch 20 Nov '12

20 Nov '12

This isn't a Boost Graph problem per se, just a graph algorithm question. Let's say I have the following graph: I want to represent this graph in a certain way. In the small legend box above, there are 2 versions of a correct answer. I want to print out each vertex followed by it's immediate adjacent vertex. If it has more than one, then each path from that point should be wrapped in a '()'. Currently, I am using the Ruby RGL package and have tried both a directed and an undirected graph using a depth first search traversal, and have yet to hit on an algorithm that takes every edge case. Anyone out there have some pointers on how to do this? Thanks! Birch

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Failing to build Boost.Test library using Clang 3.1 on Netbeans
by Paul A. Bristow 20 Nov '12

20 Nov '12

Target: i686-w64-mingw32 Thread model: posix) (This is Ruben's mingw64 build) on Netbeans 7.2 on Windows 7. The compilation stage goes OK (but with many warnings In file included from i:/boost-trunk/libs/test/src/test_tools.cpp:16: In file included from i:/boost-trunk\boost/test/impl/test_tools.ipp:23: i:/boost-trunk\boost/test/tree/test_unit.hpp:164:7: warning: 'dllexport' attribute only applies to variables and functions class BOOST_TEST_DECL master_test_suite_t : public test_suite { ^ i:/boost-trunk\boost/test/detail/config.hpp:106:29: note: expanded from macro 'BOOST_TEST_DECL' # define BOOST_TEST_DECL BOOST_SYMBOL_EXPORT ^ i:/boost-trunk\boost/config/platform/win32.hpp:30:42: note: expanded from macro 'BOOST_SYMBOL_EXPORT' # define BOOST_SYMBOL_EXPORT __declspec(dllexport) ^ <built-in>:150:38: note: expanded from macro '__declspec' #define __declspec(a) __attribute__((a)) but the link stage to build the library fails with many Cannot export boost::test_tools::tt_detail::check_impl(boost::test_tools::predicate_result const&, boost::unit_test::lazy_ostream const&, boost::unit_test::basic_cstring<char const>, unsigned int, boost::test_tools::tt_detail::tool_level, boost::test_tools::tt_detail::check_type, unsigned int, ...): symbol not found (full output window message attached). I have also failed to build using bjam (missing <cstddef> so missing the right stdlib?) and I wonder if both these are connected with lack of a suitable boost/config.hpp which caters for Clang *on this configuration*. Where would/should __clang__ be defined in order to select this compiler? My user-config.jam contains (in an attempt to cure ) # Clang compiler using mingw32 dw2 Ruben's release. using clang : 3.1 : "C:/mingw32-dw2/bin/clang++.exe" : <cxxflags>-v <cxxflags>-std="c++11" <cflags>-nostdinc # Do not include MSVC C headers. #<cflag>-c-include-dirs=??? <cxxflags>-nostdinc++ # Do not include MSVC C++ headers. # Use mingw-dw2 for includes <cxxflags>-cxx-include-arch="C:/mingw32-dw2/i686-w64-mingw32" <cxxflags>-cxx-include-32bit-dir=32 <cxxflags>-cxx-include-root="C:/mingw32-dw2/include/c++/4.6.3" <cxxflags>-stdlib=libc++ #<compileflags>-std=gnu++11 #<define>BOOST_STDLIB_CONFIG="i:/boost-trunk/boost/config/stdlib/libstdcpp3.hpp" <linkflags>-stdlib=libc++ ; Any views on my woes? Paul --- Paul A. Bristow, Prizet Farmhouse, Kendal LA8 8AB UK +44 1539 561830 07714330204 pbristow(a)hetp.u-net.com

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Re: [boost] Graph Algorithm Advice
by J Birch 19 Nov '12

19 Nov '12

Sorry, I had pasted it in the client. it is attached now. Thanks! Birch On Nov 19, 2012, at 5:03 PM, Jeremiah Willcock <jewillco(a)osl.iu.edu> wrote: > (off list) > > I don't see your attachment on there. > > -- Jeremiah Willcock > > On Mon, 19 Nov 2012, J Birch wrote: > >> This isn't a Boost Graph problem per se, just a graph algorithm question. Let's say I have the following graph: >> >> >> >> I want to represent this graph in a certain way. In the small legend box above, there are 2 versions of a correct answer. I want to print out each vertex followed by it's immediate adjacent vertex. If it has more than one, then each path from that point should be wrapped in a '()'. Currently, I am using the Ruby RGL package and have tried both a directed and an undirected graph using a depth first search traversal, and have yet to hit on an algorithm that takes every edge case. >> >> Anyone out there have some pointers on how to do this? >> >> Thanks! >> Birch >> >> _______________________________________________ >> Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost >>

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Re: [boost] Countertree
by Leo Goodstadt 19 Nov '12

19 Nov '12

On 17 November 2012 19:44, Francisco Jos? Tapia <fjtapia(a)gmail.com> wrote: > 2012/11/16 Vadim Stadnik <vadimstdk(a)gmail.com> > > On Sat, Nov 17, 2012 at 4:25 AM, Leo Goodstadt <leo.goodstadt(a)llew.org.uk wrote: > > > > > > Project location ( zip file with code and documentation) : > > > > https://dl.dropbox.com/u/8437476/works/countertree_code_doc.zip > > > > > > > > Quick view of documentation with code download : > > > > https://dl.dropbox.com/u/8437476/works/countertree/index.html > > > > > > > > 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 > > > > > > > > > Among other things, countertree would allow the boost Statistical > > > Accumulators Library to support rolling median and rolling quantiles > > > efficiently. This would be very useful. > > > > > > I had previously had to hack the tree class in the Policy-Based Data > > > Structures part of the gnu c++ library. > > > (see http://gcc.gnu.org/onlinedocs/libstdc++/ext/pb_ds/tree_order_statistics_nod… ) > > As far as I know, this support is not yet available in countertree project, > > although this is possible in principle. > > About the compatibility with the boost Statistical Accumulators Library, I > didn't thought about it, but it would be useful. I will try to implement, > but I need to examine in deep for to provide you a well founded opinion. > 1) For counter trees, the median is just the N/2-th value in the counter tree, where K is the size of the tree. The Nth-percentile can be calculated similarly. A rolling median with a fixed size window requires there to be an insertion and deletion for each (most!) new value, so I am guessing it should run in O(N log K) time, where N = size of data, K = size of window 2) The alternative is to use two multisets corresponding to values smaller and larger than the current median (or the Nth percentile). This should also have O(N log K) complexity. 3) With the special case where the data consists of integers in a fixed range, we can use a segment tree where the complexity would be O(N log R) where R = the size of the fixed range of data values. This can result in considerable speed ups. The best bit about counter trees are their flexibility, we can calculate multiple Nth-percentiles at the same time (e.g. all the quartiles). As to the actual rather than theoretical speed, I think we need bench-marking.... Leo

2 1

[boostcon12]Trouble with tuples very compiler dependent
by Larry Evans 19 Nov '12

19 Nov '12

This thread is a continuation of that started here: http://article.gmane.org/gmane.comp.lib.boost.devel/235427 It's been renamed because the new name is more topical. The tree_builder benchmarks mentioned here: http://article.gmane.org/gmane.comp.lib.boost.devel/235386 were refactored into: tuple_benchmark.tree_builder.cpp tuple_impl.bcon12_horizontal.hpp tuple_impl.bcon12_vertical.hpp and various other .hpp files. The benchmark was run as shown in the attached filt.compilation. The output after line: :filt_dr= shows with compiler=gcc4_8, the bcon12_horizontal implementation is slower than the bcon12_vertical. This agrees, at least qualitatively, with the page 12 bar chart from Eric's boostcon12 pdf file: trouble_with_tuples.pdf downloadable from here: https://github.com/boostcon/cppnow_presentations_2012/zipball/master and in the mon directory. The variadic bar in the pag12 bar chart corresponds to the: tuple_impl.bcon12_horizontal.hpp tuple implementation in the sandbox slim/test directory. The unrolled bar in the pag12 bar chart corresponds to the: tuple_impl.bcon12_vertical.hpp In contrast to the gcc4_8 compiler, with the clangxx compiler, the relative qualitative performance, is just the opposite. IOW, the bcon12_horizontal implementation is faster than the bcon12_vertical implementation. In fact, the rate of change of the performance difference accelerates as tree depth goes from 2 to 4. The rate of change is so stark that it suggests, at least to me, there may be some bug in clang. Of course that conclusion is based on almost no knowledge, on my part, of the clang implementation. The tuple_benchmark_filt.py can be modified to filter out other parts of the benchmark run output, which is here: http://svn.boost.org/svn/boost/sandbox/variadic_templates/sandbox/slim/test… In conclusion, whether it's best to use vertical or horizontal tuple implementation depends on the compiler. -regards, Larry

2 3

Build errors with msvc/release/pdb
by Christoph Macheiner 19 Nov '12

19 Nov '12

The following libraries generate errors when using msvc, building for release and generating the program debug database: date_time, locale, math (all), thread, wave. Except for math, this seems to be caused by having at least one directory specified in the /Fd option. Also, there are 251 .pdb files in the boost root directory instead of their respective output directory (presumably from serialization, unit_test, math, and most probably others). The command-line is: bjam link=shared runtime-link=shared variant=release --layout=system --stagedir=.\stage stage debug-symbols=on debug-store=database I am at a loss on how to fix this. Can someone help? On a related note, the .pdb files are automatically generated when building for debug. Is there an easy switch somewhere in the sources, so that I can turn this on globally also for release as a work-around? For reference, below is the output for the first file for each library, plus contents of the corresponding .rsp file Thanks, Christoph. ======================================== compile-c-c++ bin.v2\libs\date_time\build\msvc-11.0\release\debug-store-database\debug-symbols-on\threading-multi\gregorian\greg_month.obj greg_month.cpp libs\date_time\src\gregorian\greg_month.cpp : fatal error C1033: cannot open program database 'd:\dev\boost_1_52_0\gregorian\greg_month.pdb' call "C:\Program Files (x86)\Microsoft Visual Studio 11.0\VC\vcvarsall.bat" x86 >nul cl /Zm800 -nologo @"bin.v2\libs\date_time\build\msvc-11.0\release\debug-store-database\debug-symbols-on\threading-multi\gregorian\greg_month.obj.rsp" ---------------------------------------- "libs\date_time\src\gregorian\greg_month.cpp" -Fo"bin.v2\libs\date_time\build\msvc-11.0\release\debug-store-database\debug-symbols-on\threading-multi\gregorian\greg_month.obj" /Fd"gregorian\greg_month.pdb" -TP /O2 /Zi /Ob2 /W3 /GR /MD /Zc:forScope /Zc:wchar_t /wd4675 /EHs -c -DBOOST_ALL_DYN_LINK=1 -DBOOST_ALL_NO_LIB=1 -DDATE_TIME_INLINE -DNDEBUG "-I." ======================================== compile-c-c++ bin.v2\libs\locale\build\msvc-11.0\release\debug-store-database\debug-symbols-on\threading-multi\encoding\codepage.obj codepage.cpp libs\locale\src\encoding\codepage.cpp : fatal error C1033: cannot open program database 'd:\dev\boost_1_52_0\encoding\codepage.pdb' call "C:\Program Files (x86)\Microsoft Visual Studio 11.0\VC\vcvarsall.bat" x86 >nul cl /Zm800 -nologo @"bin.v2\libs\locale\build\msvc-11.0\release\debug-store-database\debug-symbols-on\threading-multi\encoding\codepage.obj.rsp" ---------------------------------------- "libs\locale\src\encoding\codepage.cpp" -Fo"bin.v2\libs\locale\build\msvc-11.0\release\debug-store-database\debug-symbols-on\threading-multi\encoding\codepage.obj" /Fd"encoding\codepage.pdb" -TP /O2 /Zi /Ob2 /W3 /GR /MD /Zc:forScope /Zc:wchar_t /wd4675 /EHs -c -DBOOST_ALL_NO_LIB=1 -DBOOST_LOCALE_DYN_LINK=1 -DBOOST_LOCALE_NO_POSIX_BACKEND=1 -DBOOST_SYSTEM_DYN_LINK=1 -DBOOST_THREAD_NO_LIB=1 -DNDEBUG "-I." ======================================== compile-c-c++ bin.v2\libs\math\build\msvc-11.0\release\debug-store-database\debug-symbols-on\threading-multi\assoc_laguerre.obj assoc_laguerre.cpp libs\math\build\..\src\tr1\assoc_laguerre.cpp(6) : error C2858: command-line option 'program database name (/Fdd:\dev\boost_1_52_0\assoc_laguerre.pdb)' inconsistent with precompiled header, which used '/Fdd:\dev\boost_1_52_0\vc110.pdb' libs\math\build\..\src\tr1\assoc_laguerre.cpp(6) : error C2859: d:\dev\boost_1_52_0\assoc_laguerre.pdb is not the pdb file that was used when this precompiled header was created, recreate the precompiled header. call "C:\Program Files (x86)\Microsoft Visual Studio 11.0\VC\vcvarsall.bat" x86 >nul cl /Zm800 -nologo @"bin.v2\libs\math\build\msvc-11.0\release\debug-store-database\debug-symbols-on\threading-multi\assoc_laguerre.obj.rsp" ---------------------------------------- "libs\math\build\..\src\tr1\assoc_laguerre.cpp" -Fo"bin.v2\libs\math\build\msvc-11.0\release\debug-store-database\debug-symbols-on\threading-multi\assoc_laguerre.obj" /Fd"assoc_laguerre.pdb" -Yu"pch.hpp" -Fp"bin.v2\libs\math\build\msvc-11.0\release\debug-store-database\debug-symbols-on\threading-multi\pch.pch" -TP /O2 /Zi /Ob2 /W3 /GR /MD /Zc:forScope /Zc:wchar_t /wd4675 /EHs -c -DBOOST_ALL_NO_LIB=1 -DBOOST_BUILD_PCH_ENABLED -DBOOST_MATH_TR1_DYN_LINK=1 -DNDEBUG "-I." "-Ilibs\math\src\tr1" ======================================== compile-c-c++ bin.v2\libs\thread\build\msvc-11.0\release\debug-store-database\debug-symbols-on\threading-multi\win32\thread.obj thread.cpp libs\thread\src\win32\thread.cpp : fatal error C1033: cannot open program database 'd:\dev\boost_1_52_0\win32\thread.pdb' call "C:\Program Files (x86)\Microsoft Visual Studio 11.0\VC\vcvarsall.bat" x86 >nul cl /Zm800 -nologo @"bin.v2\libs\thread\build\msvc-11.0\release\debug-store-database\debug-symbols-on\threading-multi\win32\thread.obj.rsp" ---------------------------------------- "libs\thread\src\win32\thread.cpp" -Fo"bin.v2\libs\thread\build\msvc-11.0\release\debug-store-database\debug-symbols-on\threading-multi\win32\thread.obj" /Fd"win32\thread.pdb" -TP /O2 /Zi /Ob2 /W4 /GR /MD /Zc:forScope /Zc:wchar_t /wd4675 /EHs -c -DBOOST_ALL_NO_LIB=1 -DBOOST_SYSTEM_DYN_LINK=1 -DBOOST_SYSTEM_NO_DEPRECATED -DBOOST_THREAD_BUILD_DLL=1 -DBOOST_THREAD_DONT_USE_CHRONO -DBOOST_THREAD_THROW_IF_PRECONDITION_NOT_SATISFIED -DNDEBUG "-I." ======================================== compile-c-c++ bin.v2\libs\wave\build\msvc-11.0\release\debug-store-database\debug-symbols-on\threading-multi\cpplexer\re2clex\aq.obj aq.cpp libs\wave\src\cpplexer\re2clex\aq.cpp : fatal error C1033: cannot open program database 'd:\dev\boost_1_52_0\cpplexer\re2clex\aq.pdb' call "C:\Program Files (x86)\Microsoft Visual Studio 11.0\VC\vcvarsall.bat" x86 >nul cl /Zm800 -nologo @"bin.v2\libs\wave\build\msvc-11.0\release\debug-store-database\debug-symbols-on\threading-multi\cpplexer\re2clex\aq.obj.rsp" ---------------------------------------- "libs\wave\src\cpplexer\re2clex\aq.cpp" -Fo"bin.v2\libs\wave\build\msvc-11.0\release\debug-store-database\debug-symbols-on\threading-multi\cpplexer\re2clex\aq.obj" /Fd"cpplexer\re2clex\aq.pdb" -TP /O2 /Zi /Ob2 /W3 /GR /MD /Zc:forScope /Zc:wchar_t /wd4675 /EHs -c -DBOOST_ALL_DYN_LINK=1 -DBOOST_ALL_NO_LIB=1 -DNDEBUG -D_CRT_SECURE_NO_DEPRECATE -D_SCL_SECURE_NO_DEPRECATE "-I." ========================================

2 1

User config commands needed to find Clang tools ar and ranlib
by Paul A. Bristow 19 Nov '12

19 Nov '12

I am trying to use the Clang compiler to build a Boost.Test library and have now found the necessary user-config.jam to select the compiler (thanks Jurgen Hunold) , but the link stage tools are not being found. Can anyone suggest what bjam incantation is needed ? Thanks Paul clang-linux.archive i:\boost-trunk\boost\bin.v2\libs\test\build\clang-linux-3.1\debug\link-static\runtime-link-static\th reading-multi\libboost_prg_exec_monitor-clang31-mt-sd-1_53.lib '"ar"' is not recognized as an internal or external command, operable program or batch file. '"ranlib"' is not recognized as an internal or external command, operable program or batch file. "ar" rc "i:\boost-trunk\boost\bin.v2\libs\test\build\clang-linux-3.1\debug\link-static\runtime-link-static\t hreading-multi\libboost_prg_exec_monitor-clang31-mt-sd-1_53.lib" "i:\boost-trunk\boost\bin.v2\libs\test\build\clang-linux-3.1\debug\link-static\runtime-link-static\t hreading-multi\execution_monitor.obj" "i:\boost-trunk\boost\bin.v2\libs\test\build\clang-linux-3.1\debug\link-static\runtime-link-static\t hreading-multi\debug.obj" "i:\boost-trunk\boost\bin.v2\libs\test\build\clang-linux-3.1\debug\link-static\runtime-link-static\t hreading-multi\cpp_main.obj" "ranlib" "i:\boost-trunk\boost\bin.v2\libs\test\build\clang-linux-3.1\debug\link-static\runtime-link-static\t hreading-multi\libboost_prg_exec_monitor-clang31-mt-sd-1_53.lib" ...failed clang-linux.archive i:\boost-trunk\boost\bin.v2\libs\test\build\clang-linux-3.1\debug\link-static\runtime-link-static\th reading-multi\libboost_prg_exec_monitor-clang31-mt-sd-1_53.lib... My user-config.jam contains using clang : #version 3.1 : # compiler "C:/mingw32-dw2/bin/clang++.exe" #"C:/mingw32-dw2/bin/ar.exe" <<<< actual locations of tools #"C:/mingw32-dw2/bin/ranlib.exe" <<<< actual locations of tools : # options <cxxflags>-v # verbose for testing. <cxxflags>-IC:/mingw32-dw2/include/c++/4.6.3 # for stdlib? #e:/dev/apps/mingw64/include/c++/4.7.2 <cxxflags>-IC:/mingw32-dw2/i686-w64-mingw32/include #e:/dev/apps/mingw64/include/c++/4.7.2/x86_64-w64-mingw32 # <cxxflags>-std="c++11" <root>"C:/mingw32-dw2/bin" # attempt to find the link tools ; --- Paul A. Bristow, Prizet Farmhouse, Kendal LA8 8AB UK +44 1539 561830 07714330204 pbristow(a)hetp.u-net.com

1 0

[container] Missing image
by Klaim - Joël Lamotte 19 Nov '12

19 Nov '12

Hi, I thought I pointed it already last year but there is at least one missing important image in the boost container documentation: http://www.boost.org/doc/libs/1_52_0/doc/html/container/non_standard_contai… Joel Lamotte

1 0

[#pragma once]
by Sid Sacek 18 Nov '12

18 Nov '12

I've worked with the MSVC, Sun and GCC compilers. Each one of them supports #pragma once. Is there any reason to wrap this pragma within #ifdefs? Are there any compilers out there today that don't support this #pragma? #if defined( _MSC_VER ) && ( _MSC_VER >= 1020 ) # pragma once #endif Could we change this coding pattern so that it no longer looks like MSVC is being selfish? -Sid Sacek

17 20

Re: [boost] Countertree
by Leo Goodstadt 18 Nov '12

18 Nov '12

> Subject: Re: [boost] Review Wizard Report for November 2012 > Hi all, > I would like to request a formal review of the library ?Countertree + > Suballocator? [countertree] > > Project location ( zip file with code and documentation) : > https://dl.dropbox.com/u/8437476/works/countertree_code_doc.zip > > Quick view of documentation with code download : > https://dl.dropbox.com/u/8437476/works/countertree/index.html > > For the people who don't know this project, this is a description : > > *COUNTERTREE* > > 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 Among other things, countertree would allow the boost Statistical Accumulators Library to support rolling median and rolling quantiles efficiently. This would be very useful. I had previously had to hack the tree class in the Policy-Based Data Structures part of the gnu c++ library. (see http://gcc.gnu.org/onlinedocs/libstdc++/ext/pb_ds/tree_order_statistics_nod…) Leo Goodstadt

4 5

Review Wizard Report for November 2012
by Ronald Garcia 17 Nov '12

17 Nov '12

============================================== Review Wizard Status Report for November 2012 ============================================== News ==== 1. ODEInt Reviewed 2. Boost 1.52.0 Released. No New Libraries. 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: * Predef - reviewed February 2012; review manager: Joel Falcou. * Coroutine - reviewed September 2012; review manager: Hartmut Kaiser. The following libraries have been accepted to Boost, but have not yet been submitted to SVN: * Constrained Value - accepted September 2010; author: Robert Kawulak. * GIL.IO - accepted January 2011; author: Christian Henning. * Contract - accepted September 2012; author: Lorenzo Caminiti. The following libraries have been accepted and submitted to SVN, but have not yet appeared in a release: * Atomic - accepted July 2011; author Helge Bahmann. * Type Traits Introspection - accepted August 2011; author: Edward Diener. * Lockfree - accepted August 2011; author: Tim Blechmann. The following libraries have been accepted provisionally to Boost, but have not been submitted for mini-review and full acceptance: * Endian - accepted provisionally November 2011; author: Beman Dawes. * Log - accepted provisionally March 2010; author: Andrey Semashev. 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 cmu dot edu" and "phillips at pacific dot mps dot ohio-state dot edu" 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) * Pimpl (M) * Sorting (M) * Quaternions, Vectors, Matrices (M) * Variadic Macro Data (M) * Block Pointer (M) * Singularity (M) * Extended Complex Numbers (M) * Metaparse (M) * Polygon: Voronoi Extensions * Coroutine * Range Extensions * Nowide (M) * Array (M) * TypeIndex (M) * STL Extensions (M) ``(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. Pimpl ----- :Author: Vladimir Batov :Review Manager: Needed :Download: https://github.com/boost-vault/Miscellaneous/blob/master/Pimpl.zip :Description: The Pimpl idiom is a simple yet robust technique to minimize coupling via the separation of interface and implementation and then implementation hiding. This library provides a convenient yet flexible and generic deployment technique for the Pimpl idiom. It's seemingly complete and broadly applicable, yet minimal, simple and pleasant to use. Sorting ------- :Author: Steven Ross :Review Manager: Needed :Download: https://github.com/boost-vault/Sorting :Description: A grouping of 3 templated hybrid radix/comparison-based sorting algorithms that provide superior worst-case and average-case performance to std::sort: integer_sort, which sorts fixed-size data types that support a rightshift (default of >>) and a comparison (default of <) operator. float_sort, which sorts standard floating-point numbers by safely casting them to integers. string_sort, which sorts variable-length data types, and is optimized for 8-bit character strings. All 3 algorithms have O(n(k/s + s)) runtime where k is the number of bits in the data type and s is a constant, and limited memory overhead (in the kB for realistic inputs). In testing, integer_sort varies from 35% faster to 2X as fast as std::sort, depending on processor, compiler optimizations, and data distribution. float_sort is roughly 70% faster than std::sort. string_sort is roughly 2X as fast as std::sort. Quaternions, Vectors, Matrices ------------------------------ :Author: Emil Dotchevski :Review Manager: Needed :Download: http://www.revergestudios.com/boost-qvm/ :Description: QVM defines a set of generic functions and operator overloads for working with quaternions, vectors and matrices of static size. The library also defines vector and matrix data types, however it allows users to introduce their own types by specializing the q_traits, v_traits and m_traits templates. Variadic Macro Data ------------------- :Author: Edward Diener :Review Manager: Needed :Download: `Boost Sandbox <http://svn.boost.org/svn/boost/sandbox/variadic_macro_data/>`__ :Description: This library adds support and functionality for variadic macros to Boost as well as integrating variadic macros with the Boost PP library without changing the latter library in any way. 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) Metaparse --------- :Author: Abel Sinkovics :Review Manager: Needed :Download: http://abel.web.elte.hu/metaparse/metaparse.zip :Description: Metaparse is a library for constructing parsers parsing at compile-time based on template metaprogramming. The parsers built with the library take boost::mpl::strings as input and can produce - types - objects (types with public static members) - callable C++ functions (types with public static method) - template metafunction classes as output (based on the input being parsed). On compilers supporting constexpr the library provides the following syntactic sugar for writing the input of the parsers: BOOST_STRING("this is a string") The library can be used for implementing DSLs in C++, including DSLs making C++ template metaprogramming easier (see examples). Polygon: Voronoi Extensions --------------------------- :Author: Andril Sydorchuk :Review Manager: Lucanus Simonson :Download: http://svn.boost.org/svn/boost/sandbox/gtl/ :Description: This library extends Boost.Polygon with the following features: - Robust and efficient implementation of the sweepline algorithm that allows to construct Voronoi diagram, Delaunay triangulation and medial axis of a set of points and line segments. - Coordinates of the output geometries are computed within the 64 machine epsilon relative error (6 mantissa bits). - Voronoi diagram data structure that allows efficient traversal and data association with the output Voronoi graph. - No 3rd party dependencies (e.g. GMP, MPFR), all the required multiple precision types are implemented as part of the library. - The input and output coordinate type domains are configurable via coordinate type traits, thus allowing to compute coordinates of the Voronoi vertices within any required precision. - The full construction of the Voronoi diagram of 100 000 points takes only 0.27 seconds (see benchmarks). Coroutine --------- :Author: Oliver Kowalke :Review Manager: Hartmut Kaiser :Download: http://gitorious.org/boost-dev/boost-dev/archive-tarball/coroutine :Description: This library is an implementation of coroutines and generators using Boost.Context. 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. TypeIndex --------- :Author: Antony Polukhin :Review Manager: Needed :Download: https://github.com/apolukhin/type_index :Description: TypeIndex is an extended C++11 type_index library, that * works with disabled RTTI * can store const-volatile-reference info about types (if user requested it) * has all the functionality of std::type_index * has portable across compilers and platforms functionality for getting demangled type names * works across modules/shared libraries * does not require C++11 to work 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. Libraries under development =========================== See http://svn.boost.org/trac/boost/wiki/LibrariesUnderConstruction for a current listing of libraries under development.

3 8

[1.53] request to merge lockfree (c++11 only)
by Tim Blechmann 17 Nov '12

17 Nov '12

hi all, i'm not sure about the state of atomic, as the original author hardly reacts on emails and atm, i don't have the time to adopt it ... i'd therefore request permission to merge boost.lockfree into release, depending on std::atomic<>. this means, that it will require gcc-4.8 or msvc 2012 in c++11 mode to compile it (not sure about clang++, as their c++11 support under linux is pretty broken). the architecture of boost.lockfree is modular, so once boost.atomic is merged, it is trivial to use it again and allow use of the library with pre-c++11 compilers ... this is far from ideal, but boost.atomic has been blocking the release of boost.lockfree for a long time and it doesn't look like that it will be available before std::atomic<> is widely supported ... thoughts? tim

5 13

1.53 schedule change
by Daniel James 17 Nov '12

17 Nov '12

Hello everyone, I just noticed that I forgot to account for Christmas when setting the schedule for 1.53. I've adjusted it so that the deadlines for new libraries and major changes are a week earlier (as specified on the release schedule page). Sorry about that. There's still 3 weeks before the new library deadline, but please let us know soon if you have a new library for 1.53. thanks, Daniel

3 6

Boost.Process 0.5: Another update/potential candidate for an official library
by Boris Schaeling 17 Nov '12

17 Nov '12

I've uploaded a new version of Boost.Process 0.5 to <http://www.highscore.de/boost/process0.5/>: - Made child movable and non-copyable on Windows (destructor closes handles) - Added cross-platform helpers in a new header file boost/process/mitigate.hpp - Updated and improved documentation (eg. FAQ is new) - Added the POSIX initializer notify_io_service (Boost.Asio helper) - Minor bug fixes and improvements (eg. in search_path() on Windows) At this point there is nothing left on my todo list. I got quite a lot of feedback so far and would appreciate if people can look at this new version again. If there are no major shortcomings found, I'll ask for a formal review. Boris

10 53

[container] container_detail::pair piecewise constructor
by László Szécsi 17 Nov '12

17 Nov '12

Hi everyone, boost::container::container_detail::pair's piecewise constructor is missing, as acknowledged in a comment. This makes container::flat_map::emplace less useful (perhaps useless) as the following will not work: boost::container::flat_multimap<TestKey, TestValue> testMap; testMap.emplace(boost::container::container_detail::piecewise_construct, boost::make_tuple(30), boost::make_tuple(50)); where both TestKey and TestValue are non-copyable, moveable classes with a constructor taking an int. The compilation error message will correctly say that boost::container::container_detail::pair does not have a constructor with three arguments. I tried to implement the missing piecewise constructor based on std::pair's in the g++ standard libraries. I failed at it, so I would like to request some assistance and education. This is where I got: // from the standard lib template<std::size_t _Num> struct _Build_index_tuple { typedef typename _Build_index_tuple<_Num-1>::__type::__next __type; }; // from the standard lib template<> struct _Build_index_tuple<0> { typedef _Index_tuple<> __type; }; template <class... Args1, class... Args2> pair(piecewise_construct_t, ::boost::tuple<Args1...> first_args, ::boost::tuple<Args2...> second_args) : pair(::boost::move(first_args), ::boost::move(second_args), typename _Build_index_tuple<sizeof...(Args1)>::__type(), typename _Build_index_tuple<sizeof...(Args2)>::__type()) {} template<typename... Args1, std::size_t... Indices1, typename... Args2, std::size_t... Indices2> explicit pair(tuple<Args1...> tuple1, tuple<Args2...> tuple2, _Index_tuple<Indices1...>, _Index_tuple<Indices2...>) : first(::boost::forward<Args1>(std::get<Indices1>(tuple1))...), second(::boost::forward<Args2>(std::get<Indices2>(tuple2))...) { } This gets me a recursive error message far too long to quote, starting with: error C2664: 'boost::container::container_detail::pair<Key,T>::pair(std::pair<Key,T> &&)' : cannot convert parameter 3 from 'boost::tuples::tuple<int,boost::tuples::null_type // lot of null_types omitted to 'boost::tuples::tuple<boost::tuples::null_type, // lot of null_types omitted I used the VS2012 Nov CTP compiler. I understand that variadic templates have not been very portable and boost::unordered, which has a piecewise constructor implementation, does it completely differently and much more painfully. But is there a reason for the approach I tried not to work with boost at all? Could you please help me fix this code? Thank you very much, Laszlo Szecsi

3 3

Updated serialization performance tests
by Brian Wood 16 Nov '12

16 Nov '12

Shalom I've updated this page -- http://webEbenezer.net/comparison.html with results from Boost 1.52. A few notes about the testing: I decided to use -O2 on the Linux/g++ tests. In previous tests I used -O3. I hadn't updated the Windows test results since the Boost 1.48 time-frame. Around Boost 1.51 I had to start building the serialization library in Boost with runtime-link=static in order to get the Windows tests to build. I haven't understood why that became necessary, but the results for the serialization library in Boost seem to have been adversely affected by this. On Windows, I now report that tests built with the serialization library in Boost are over 1.8 times slower than parallel Ebenezer tests. Previously I reported the tests built with the serialization library in Boost were between 1.7 and 1.8 times slower than the Ebenezer tests. -- Brian Ebenezer Enterprises -- making programming fun again. http://webEbenezer.net

1 0

Boost.Test and Xcode 4.5 in C++11 Mode
by Dean Michael Berris 16 Nov '12

16 Nov '12

Hi Everyone, I'm trying to build Boost.Test in trunk in C++11 mode with Apple's released Clang compiler with Xcode 4.5. Is this supported by Boost.Test? I keep getting this error somewhere deep in some preprocessor parts which is far outside my understanding. Here's my user-config.jam: using clang : : : <cxxflags>-Wall <cxxflags>-Wself-assign <cxxflags>-std=c++11 <cxxflags>-stdlib=libc++ <linkflags>-stdlib=libc++ ; I ask because I'm using Boost.Test as my current unit testing framework for cpp-netlib. I'm going to need to make a decision on whether I can continue using Boost.Test in C++11 mode as cpp-netlib is moving to C++11-only in its next version. Thanks in advance. -- Dean Michael Berris www.deanberris.com

5 13

[test] A new ERROR in trunk including C++11 features on C++98 mode
by Vicente J. Botet Escriba 16 Nov '12

16 Nov '12

Hi, there is yet an error including C++11 features. Please could you take care of it? Thanks, Vicente darwin.compile.c++ ../../../bin.v2/libs/test/build/darwin-4.2.1/debug/link-static/threading-multi/framework.o In file included from ../../../boost/test/tools/assertion.hpp:19, from ../../../boost/test/tools/impl.hpp:25, from ../../../boost/test/test_tools.hpp:373, from ../../../boost/test/impl/framework.ipp:27, from ../../../libs/test/src/framework.cpp:16: ../../../boost/test/utils/is_forward_iterable.hpp:58: error: ‘>>’ should be ‘> >’ within a nested template argument list ../../../boost/test/utils/is_forward_iterable.hpp:61: error: ‘>>’ should be ‘> >’ within a nested template argument list "g++" -ftemplate-depth-128 -O0 -fno-inline -Wall -pedantic -g -gdwarf-2 -fexceptions -DBOOST_ALL_NO_LIB=1 -I"../../.." -c -o "../../../bin.v2/libs/test/build/darwin-4.2.1/debug/link-static/threading-multi/framework.o" "../../../libs/test/src/framework.cpp" ...failed darwin.compile.c++ ../../../bin.v2/libs/test/build/darwin-4.2.1/debug/link-static/threading-multi/framework.o...

6 16

BOOST_FUSION_ADAPT_STRUCT - Printing Array Elements
by forums_mp 16 Nov '12

16 Nov '12

Given the snippet below. How do I print the contents within the array ? I'd expect to see a counting pattern when the array is encountered but that's not the case. Thanks in advance. [code] #include <boost/mpl/eval_if.hpp> #include <boost/mpl/identity.hpp> #include <boost/mpl/next_prior.hpp> #include <boost/fusion/mpl.hpp> #include <boost/fusion/adapted.hpp> // BOOST_FUSION_ADAPT_STRUCT // boost::fusion::result_of::value_at #include <boost/fusion/sequence/intrinsic/value_at.hpp> #include <boost/fusion/include/value_at.hpp> // boost::fusion::result_of::size #include <boost/fusion/sequence/intrinsic/size.hpp> #include <boost/fusion/include/size.hpp> // boost::fusion::at #include <boost/fusion/sequence/intrinsic/at.hpp> #include <boost/fusion/include/at.hpp> # include <iostream> # include <vector> typedef std::vector < int > INT_VEC ; // Your existing struct struct my_struct { int i; bool j; int arr1 [ 100 ]; // INT_VEC vv ; // my_struct() // : vv ( 100 ) // {} }; // Generate an adapter allowing to view "Foo" as a Boost.Fusion sequence BOOST_FUSION_ADAPT_STRUCT( my_struct, (int, i) (bool, j) (int, arr1[ 100 ] ) // (int, vv[100]) ) template <typename T2> struct parse_foo { static void parse(T2 & f); }; struct display { template <typename T> void operator()(T& t) const { std::printf(" --%s--%s-- \n", typeid(t).name(), boost::lexical_cast<std::string>(t).c_str()); if (typeid(t).name()[0] == 'c') std::printf(" --%s--%s-- \n", typeid(t).name(), t); parse_foo<T>::parse(t); } }; template <> void parse_foo<int >::parse(int & f) { std::cout << f << std::endl; } template <> void parse_foo<char>::parse(char & f) {}; template <> void parse_foo<bool>::parse(bool & f) { std::cout << f << std::endl; }; #include <boost/fusion/include/sequence.hpp> #include <boost/fusion/include/algorithm.hpp> #include <boost/fusion/include/vector.hpp> #include <boost/fusion/include/adapt_struct.hpp> #include <boost/lexical_cast.hpp> int main() { my_struct f; f.i = 33 ; f.j = false ;; for ( int odx ( 0 ); odx < 100; ++odx ) { f.arr1 [ odx ] = odx ; } boost::fusion::for_each(f, display()); } [/code] -- View this message in context: http://boost.2283326.n4.nabble.com/BOOST-FUSION-ADAPT-STRUCT-Printing-Array… Sent from the Boost - Dev mailing list archive at Nabble.com.

1 0

Re: [boost] [Boost-commit] svn:boost r81360 - in trunk: boost/algorithm libs/algorithm/test
by Steven Watanabe 15 Nov '12

15 Nov '12

AMDG On 11/15/2012 11:45 AM, marshall(a)idio.com wrote: > <snip> > + // construct/copy > + BOOST_CONSTEXPR basic_string_ref () > +#ifdef BOOST_NO_CXX11_NULLPTR > + : ptr_(NULL), len_(0) {} > +#else > + : ptr_(nullptr), len_(0) {} > +#endif Really? The two branches have exactly the same effect. The only reason to prefer nullptr is aesthetic and this is more than offset by the #ifdef. > + > + basic_string_ref(const charT* str) > + : ptr_(str), len_(std::strlen(str)) {} > + strlen only works for char. You need to use traits::length > +#ifndef BOOST_NO_CXX11_HDR_INITIALIZER_LIST > +// !! How do I do this? Look how initializer_lists work! > + basic_string_ref(std::initializer_list<charT> il); // TODO > +#endif > + Although this can be implemented, it's incredibly dangerous, because the string_ref will be left dangling when the initializer_list goes out of scope. > + > + // iterators > + BOOST_CONSTEXPR const_iterator begin() const { return ptr_; } > + BOOST_CONSTEXPR const_iterator cbegin() const { return ptr_; } > + BOOST_CONSTEXPR const_iterator end() const { return ptr_ + len_; } > + BOOST_CONSTEXPR const_iterator cend() const { return ptr_ + len_; } > + const_reverse_iterator rbegin() const { return const_reverse_iterator (end()); } > + const_reverse_iterator crbegin() const { return const_reverse_iterator (end()); } > + const_reverse_iterator rend() const { return const_reverse_iterator (begin()); } > + const_reverse_iterator crend() const { return const_reverse_iterator (begin()); } > + Check for tabs? > + // capacity > + BOOST_CONSTEXPR size_type max_size() const { return len_; } I'm not convinced that this definition is correct. Returns: the size of the largest possible string. Note that this does not say that it returns the maximum size that this particular string_ref object can hold without reassignment. > + > + int compare(basic_string_ref x) const { > + int cmp = std::memcmp ( ptr_, x.ptr_, std::min(len_, x.len_)); > + return cmp != 0 ? cmp : ( len_ == x.len_ ? 0 : len_ < x.len_ ? -1 : 1 ); > + } > + > + bool starts_with(charT c) const { return !empty() && front() == c; } > + bool starts_with(basic_string_ref x) const { > + return len_ >= x.len_ && std::memcmp ( ptr_, x.ptr_, x.len_ ) == 0; > + } > + > + bool ends_with(charT c) const { return !empty() && back() == c; } > + bool ends_with(basic_string_ref x) const { > + return len_ >= x.len_ && std::memcmp ( ptr_ + len_ - x.len_, x.ptr_, x.len_ ) == 0; > + } > + You can only use memcmp for char. You have to use traits::compare here. > + > +// Have to use traits here > + size_type find(basic_string_ref s) const { > + const_iterator iter = std::find_if ( this->cbegin (), this->cend (), > + s.cbegin (), s.cend (), traits::eq ); > + return iter = this->cend () ? npos : std::distance ( this->cbegin (), iter ); > + } > + I think you mean std::search, not std::find_if. > + size_type find(charT c) const { > +#ifdef BOOST_NO_CXX11_LAMBDAS > + const_iterator iter = std::find_if ( this->cbegin (), this->cend (), > + detail::string_ref_traits_eq<charT, traits> ( c )); > +#else > + const_iterator iter = std::find_if ( this->cbegin (), this->cend (), > + [c] ( charT val ) { return traits::eq ( c, val ); } ); > +#endif > + return iter == this->cend () ? npos : std::distance ( this->cbegin (), iter ); > + } > + As with NULL/nulptr, I don't see the point of using C++11 lambdas if you have to #ifdef it with a C++03 implementation. In Christ, Steven Watanabe

2 1

[multiprecision] OK to merge to Trunk?
by John Maddock 15 Nov '12

15 Nov '12

Folks, Unless there are any objections, I'd like to merge the multiprecision library to SVN Trunk pretty soon. Here are the main changes since the review, which have mostly concentrated on the interface changes: * Non-expression template operators further optimized with rvalue reference support. * Many functions made `constexp`. * Differentiate between explicit and implicit conversions in the number constructor. * Removed "mp_" prefix from types. * Allowed mixed precision arithmetic. * Changed ExpressionTemplates parameter to class `number` to use enumerated values rather than true/false. * Changed ExpressionTemplate parameter default value to use a traits class so that the default value depends on the backend used. * Added support for fused-multiply-add/subtract with GMP support. * Tweaked expression template unpacking to use fewer temporaries when the LHS also appears in the RHS. * Refactored `cpp_int_backend` based on review comments with new template parameter structure. * Added additional template parameter to `mpfr_float_backend` to allow stack-based allocation. * Added section on mixed precision arithmetic, and added support for operations yielding a higher precision result than either of the arguments. * Added overloads of integer-specific functions for built in integer types. Things requested in review, but not yet done: * We can reuse temporaries in multiple subtrees (temporary caching). Low priority for now. * cpp_dec_float should round to nearest. Chris currently has no time for this, and it's really hard to do *right*. * A 2's complement fixed precision int that uses exactly N bits and no more. Refactoring of cpp_int should make this easier to add as an option in future. There are also documentation updates pending (mostly relating to the new improved performance results), and more tests I want to add/run, bit basically I need to get things widely tested to move forward now. Release schedule wise, I think it'll be hard to get things ready for the next release, but the release after that really should be on the cards. So basically now is the last chance for folks to complain before the interface gets ossified ;-) As ever current code is in the sandbox under /big_number/ and docs can be viewed online here: http://svn.boost.org/svn/boost/sandbox/big_number/libs/multiprecision/doc/h… Regards, John.

7 10

boost filesystem path as utf-8 revisited
by Rush Manbert 15 Nov '12

15 Nov '12

In the original thread, I found this reply by Beman: ----------------- > > > How exactly do I imbue UTF-8 codecvt in a path? I Googled around and > couldn't find anything. There are two approaches: * If you always want all class path arguments and returned values with a value type of char to be treated as being UTF-8 encoded, and aren't worried about changing a potentially dangerous global, then do this: #include <boost/filesystem/detail/utf8_codecvt_facet.hpp> ... std::locale global_loc = std::locale(); std::locale loc(global_loc, new boost::filesystem::detail::utf8_codecvt_facet); boost::filesystem::path::imbue(loc); ----------------- I do want what is described and would like to use this approach, but we use boost::filesystem all over the place and in our code we never do any sort of "global initialization", so I'm trying to figure out how to get the code snippet executed. I can see two ways to approach this: 1) Add this code snippet to the boost::filesystem::path constructor. But is it too late then? 2) Define a class whose only purpose is to execute this code when it is constructed and arrange to have a static singleton instance of the class defined. In one of our libraries we need to be very careful about static class construction order, so this may be difficult. I haven't dealt with this sort of issue in quite a while and I may be a little rusty. Any suggestions? Are there new goodies in C++ that might help me? Thanks, Rush

3 3

program_options::store() interface extension
by ST 15 Nov '12

15 Nov '12

Hi, I need to supply to my app a config file with following entries: item1 = 123 item2 = 435 item3 = 345 ... itemN = 562 where N is not known in advance, so there is no way to register such options. The only way to deal with them is to pass them as unregistered options and then use collect_unrecognized(). But then dealing with a vector<string> is not quit convenient. My suggestion is to add an a storeUnregistered flag to the store() function which will be false by default, but if set to true, will store all unregistered options with their values as strings. It will be possible then to check whether an item was provided like this: vm.count("item1") and cast its value like this: vm["item1"].as<int>() . Or is there already a good way to do what I need? Thank you in advance, ST

2 1

Re: [boost] [container] container_detail::pair piecewise constructor
by László Szécsi 15 Nov '12

15 Nov '12

I did some more research and it turns out std-style piecewise construction fails with VS2012 Nov CTP compiler, just like my attempt at adding piecewise construction to boost::container_detail::pair. In particular, the following dummy code compiles under g++ 4.7.1 but not under VS2012 Nov CTP. class Foo { public: template <class... Args1, class... Args2> Foo( const ::std::piecewise_construct_t, ::std::tuple<Args1...> first_args, ::std::tuple<Args2...> second_args) { } }; int main(){ Foo s( std::piecewise_construct, std::move( std::make_tuple(30) ), std::move( std::make_tuple(50) )); } I guess the time is not ripe for the container implementation to use true variadic templates yet. Is there ongoing effort to implement container_detail::pair's piecewise constructor in the same way as it was implemented in boost::unordered? Best regards, Laszlo Szecsi

1 0

[optional] Support for moving values
by Adam Badura 14 Nov '12

14 Nov '12

Are there any plans to add support for move constructors and assignment operators? I noticed that many Boost libraries miss that support. And it is especially "visible" in case of such utilities like boost::optional or boost::variant. Adam Badura

2 1

Boost 1.52.0 released!
by Marshall Clow 14 Nov '12

14 Nov '12

Release 1.52.0 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 numerous enhancements and bug fixes for existing libraries. For details, including download links, see http://www.boost.org/users/news/version_1_52_0 You can also download directly from SourceForge: http://sourceforge.net/projects/boost/files/boost/1.52.0/ 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 Beman Dawes Daniel James Eric Niebler Marshall Clow Rene Rivera Vladimir Prus

9 11

[optional] Types without assignment operator
by Adam Badura 14 Nov '12

14 Nov '12

I use boost::optional for deferred construction. Something similar to the idea described in "Bypassing expensive unnecessary default construction" in Boost.Optional documentation. Only in my case I do this because the mentioned construction requires virtual function calls and this cannot be done in owning object constructor and has to be postponed. So instead of accessing the object directly I always access it by a function. That function first checks if the object is already constructed (boost::optional is initialized) and if so just returns it. Otherwise it first constructs it. That approach requires only copy construction (or even move construction if boost::optional would support moving in the first place). Yet due to implementation details the embedded type has to be assignable as well. Even thou assignment operator will never be called (in this scenario). Is there a way to avoid this issue? If not then how about adding a function like "assign" (possibly named otherwise or with additional defaulting argument) which could assign by first destroying old object (if any) and then copy/move constructing a new one. This would obviously be bad from exception safety (guarantees) point of view, but well... don't call the function if you don't like that. And in scenarios like mine it would not be an issue since there would be no object to destroy anyway. (Also the function could assert/throw on that condition...) Now the Synopsis part of the Boost.Optional documentation does mention (Typed)InPlaceFactory assign operators which do look promising for solving this issue. But firstly they are not documented in following Detailed Semantics part. There is even no link in the Synopsis. (Is this docs bug? In which part? Missing docs or extra functions?) And secondly (Typed)InPlaceFactory support is "intrusive". I cannot add it to a class without changing the class itself. And in my case I cannot change the class (boost::program_options::options_description - why cannot it be copy assigned, that I don't know...). Maybe adding some extra wrapper would help but I don't think it would be a solution. Rather a somewhat ugly workaround. Adam Badura

3 8

Possible submission: Expanded std::bind compatible with std::move
by スマートアシュリー 14 Nov '12

14 Nov '12

I noticed that std::bind inst compatible with std::move.. I created a workaround for it in c++11 here. I would like to see it added to boost if thats ok. Please review my code... and let me know if its a viable candidate to be added to boost and what code changes are need before that. http://code-slim-jim.blogspot.jp/2012/11/perfect-forwarding-bind-compatable…

2 1

[type_erasure] issue when taking any<> by const ref
by Thomas Petit 13 Nov '12

13 Nov '12

Hi, I'm playing with the boost type erasure library (from the sandbox) and hit some issues. Imagine that I have an any accepting some concept : > typedef any<concept1<>, concept2<>> some_any_t; and a std::vector to put a few any in it : > std::vector<some_any_t> v; Then If I iterate over the vector by taking each element by reference >for(some_any_t& : v) >{ >} everything is fine and consistent with why I expect. However if I iterate by taking element by const ref >for(const some_any_t& : v) >{ >} then some issue appears. Here is an example showing the problems (with one any using a concept defined by BOOST_TYPE_ERASURE_FREE and one any using a concept defined by BOOST_TYPE_ERASURE_MEMBER) ................................................... #include <boost/type_erasure/any.hpp> #include <boost/type_erasure/operators.hpp> #include <boost/type_erasure/free.hpp> #include <boost/type_erasure/member.hpp> namespace mpl = boost::mpl; namespace te = boost::type_erasure; template <typename T> void free(const T& t) { std::cout << typeid(t).name() << std::endl; std::cout << "default free\n"; } void free(const int& i) { std::cout << typeid(i).name() << std::endl; std::cout << "int\n"; } BOOST_TYPE_ERASURE_FREE((has_free), free, 1); template<class T = te::_self> struct free_concept : mpl::vector<has_free<void(const T&)> > {}; typedef te::any<mpl::vector<te::copy_constructible<>, free_concept<>>> any_free_t; struct Base { virtual void member() const { std::cout << "Base member\n"; } }; struct Derived : public Base { virtual void member() const { std::cout << "Derived member\n"; } }; BOOST_TYPE_ERASURE_MEMBER((has_member), member, 0) struct member_concept : mpl::vector<has_member<void()> > {}; typedef te::any<mpl::vector<te::copy_constructible<>, member_concept>> any_member_t; int main() { any_free_t af1(5); any_free_t af2(5.0); std::vector<any_free_t> v; v.push_back(af1); v.push_back(af2); for(any_free_t& af : v) { free(af); } Base b; Derived d; std::vector<any_member_t> v2; v2.push_back(b); v2.push_back(d); for(any_member_t& am : v2) { am .member(); } } ....................................................... In the previous code, if add a const here : for(const any_free_t& af : v) { free(af); } then instead of calling the int overload of the free function and the template overload with a double type, the templated free function is called both time but, unfortunately the type of T is always the same as the any. Another point, if I add a const here : for(const any_member_t& am : v2) { am .member(); } then I get a compile error. (with visual 2012 and gcc 4.7) I'm a bit puzzled by this behavior. Are any<> types never supposed to be taken by const ref ? How can we iterate over anys while preserving constness ? Thanks. Thomas.

2 2

boost threads and linking boost statically into a DLL
by Carlos Empujon 13 Nov '12

13 Nov '12

Recently I had some trouble to linking boost statically into a DLL. After searching around I found that there has been a discussion on http://boost.2283326.n4.nabble.com/Fwd-Thread-Solution-to-conflict-with-MFC… However it seems that the patch proposed there (see below) did not make it into the trunk. Has there been a special reason why this has not been included into the normal distribution? Cheers, Carlos /** * tss.cpp * * This file is intended to correctly build a dll using boost::thread * It is taken from * * http://boost.2283326.n4.nabble.com/Fwd-Thread-Solution-to-conflict-with-MFC… * * $Id$ */ #include <windows.h> #include <boost/thread/detail/tss_hooks.hpp> extern "C" BOOL WINAPI RawDllMain(HINSTANCE hInstance, DWORD dwReason, LPVOID); namespace { BOOL WINAPI dll_callback(HANDLE h, DWORD dwReason, LPVOID p) { #ifdef _DLL if(!RawDllMain(static_cast<HINSTANCE>(h),dwReason,p)) return false; #endif // _DLL switch (dwReason) { case DLL_THREAD_DETACH: boost::on_thread_exit(); break; case DLL_PROCESS_DETACH: boost::on_process_exit(); break; } return true; } } extern "C" { extern BOOL (WINAPI * const _pRawDllMain)(HANDLE, DWORD, LPVOID)=&dll_callback; } namespace boost { void tss_cleanup_implemented() {} }

1 0

Release branch now open for merging
by Marshall Clow 12 Nov '12

12 Nov '12

The release branch (https://svn.boost.org/svn/boost/branches/release) is open for merging all stable changes from trunk, including bug fixes and major upgrades to existing libraries. Breaking changes should be coordinated via the mailing list with the developers of the other libraries affected. New libraries may be added, but require permission of a release manager. In other words, merging *does not* require permission from a release manager, except for new libraries. Boost Calendar with the release schedule: http://www.boost.org/development/index.html Release schedule explanation: http://svn.boost.org/trac/boost/wiki/ReleaseSchedule Release practices for developers: http://svn.boost.org/trac/boost/wiki/ImprovingPractices -- The Release Managers, Beman Dawes Daniel James Eric Niebler Marshall Clow Rene Rivera Vladimir Prus

1 0

[iostream] Bug in indirect_streambuf::seek_impl
by Jorge Lodos Vigil 12 Nov '12

12 Nov '12

Hi Currently indirect_streambuf::seek_impl always modifies input and output pointers with code: setg(0, 0, 0); setp(0, 0); See detail/indirect_streambuf.hpp. However, this is incorrect for dual seekable streams buffers which only modifies one set of pointers on each seek (in or out). As a consequence, dual seekable devices cannot be correctly seek. Those 2 lines should be replaced by: if (is_convertible<category, dual_seekable>::value) { if (which == BOOST_IOS::in) { setg(0, 0, 0); } if (which == BOOST_IOS::out) { setp(0, 0); } } else { setg(0, 0, 0); setp(0, 0); } I have created ticket https://svn.boost.org/trac/boost/ticket/7681 Thanks, Jorge

1 0

enable_if quirk? bug?
by Gennadiy Rozental 12 Nov '12

12 Nov '12

Hi, While working on some portability for Boost.Test I found this weird behavior. Abstracting out Boost.Test specific staff it goes like this: template<typename T> inline typename boost::enable_if_c<!boost::is_float<T>::value, int>::type foo( T&& v ); template<typename T> inline typename boost::enable_if_c<!boost::is_float<T>::value, int>::type foo( T&& v ) { return 1; } ... foo(1); MSVC 10 producing this error: error C2668: 'foo' : ambiguous call to overloaded function test.cpp(31): could be 'int foo<int>(T &&)' with [ T=int ] test.cpp(27): or 'int foo<int>(T &&)' with [ T=int ] while trying to match the argument list '(int)' Now change boost::enable_if_c with seemingly equivalent std::enable_if: template<typename T> inline typename std::enable_if<!boost::is_float<T>::value, int>::type foo( T&& v ); template<typename T> inline typename std::enable_if<!boost::is_float<T>::value, int>::type foo( T&& v ) { return 1; } and MSVC 10 is happy to accept this code. This is somewhat unfortunate since I hoped to use boost::enable_if across compilers. Gennadiy

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