- Boost - lists.preview.boost.org

[Container] 'to_pointer' problem since 1.52
by Rich E 18 Dec '12

18 Dec '12

Just wanted to point out that there's an outstanding bug report due to some changes in Boost.Container that seem to have occured somewhere in the 1.52 dev cycle, reported here <https://svn.boost.org/trac/boost/ticket/7650>. In a nutshell, there is a compile time error caused by boost::container::list::const_iterator is trying to use a method called 'to_pointer' that doesn't exist (there is a 'pointer_to' method defined). We're using a modified version of boost/container/list.hpp at the moment, but it would be nice to ditch that come 1.53. The patch is so trivial that I thought it best to leave it up to the maintainer, as I really have no idea how to work with the current svn setup. cheers, Rich

2 1

Another set of macros to deprecate (and then remove)?
by Marshall Clow 18 Dec '12

18 Dec '12

There are a set of macros in Boost.config that describe "features that are not required by the C++ standard" Some of these features have been incorporated into C++11. I propose that we retire these macros, and have people use the shiny C++11 versions. In particular: BOOST_HAS_STATIC_ASSERT should be ! BOOST_NO_CXX11_ASSERT BOOST_HAS_VARIADIC_TMPL should be ! BOOST_NO_CXX11_VARIADIC_TEMPLATES BOOST_HAS_RVALUE_REFS should be ! BOOST_NO_CXX11_RVALUE_REFERENCES BOOST_HAS_CHAR_16_T should be ! BOOST_NO_CXX11_CHAR_16_T BOOST_HAS_CHAR_32_T should be ! BOOST_NO_CXX11_CHAR_32_T I'm using "!" here generically; in code you would replace #ifdef OLD_MACRO with #ifndef NEW_MACRO etc. I don't think this will be very disruptive; very few boost libraries use these macros. Opinions? Other macros that fit into this group? -- Marshall Marshall Clow Idio Software <mailto:mclow.lists@gmail.com> A.D. 1517: Martin Luther nails his 95 Theses to the church door and is promptly moderated down to (-1, Flamebait). -- Yu Suzuki

8 12

compilation warning on HEAD
by Gaetano Mendola 18 Dec '12

18 Dec '12

The HEAD in trunk have some compilation warnings using gcc 4.7.2 the following will fix some of those. Another warning about unused result is in here: libs/serialization/src/basic_iarchive.cpp line 576, the value is used in a BOOST_ASSERT, I don't know how you manage those cases. Regards Gaetano Mendola Index: libs/serialization/src/basic_serializer_map.cpp =================================================================== --- libs/serialization/src/basic_serializer_map.cpp (revision 81900) +++ libs/serialization/src/basic_serializer_map.cpp (working copy) @@ -43,8 +43,7 @@ BOOST_ARCHIVE_DECL(bool) basic_serializer_map::insert(const basic_serializer * bs){ // attempt to insert serializer into it's map - const std::pair<map_type::iterator, bool> result = - m_map.insert(bs); + m_map.insert(bs); // the following is commented out - rather than being just // deleted as a reminder not to try this. Index: boost/archive/iterators/transform_width.hpp =================================================================== --- boost/archive/iterators/transform_width.hpp (revision 81900) +++ boost/archive/iterators/transform_width.hpp (working copy) @@ -112,6 +112,7 @@ transform_width(BOOST_PFTO_WRAPPER(T) start) : super_t(Base(BOOST_MAKE_PFTO_WRAPPER(static_cast< T >(start)))), m_buffer_out_full(false), + m_buffer_in(), m_remaining_bits(0), m_end_of_sequence(false) {} @@ -119,8 +120,8 @@ transform_width(const transform_width & rhs) : super_t(rhs.base_reference()), m_buffer_out_full(rhs.m_buffer_out_full), + m_buffer_in(rhs.m_buffer_in), m_remaining_bits(rhs.m_remaining_bits), - m_buffer_in(rhs.m_buffer_in), m_end_of_sequence(false) {} }; -- cpp-today.blogspot.it

4 4

[Git] Documentation for Git and Modular Boost conversion
by Beman Dawes 18 Dec '12

18 Dec '12

We are starting to pull together documentation for the Git and Modular Boost conversion. https://svn.boost.org/trac/boost/wiki/WikiStart#GitandModularBoost Comments and corrections welcome! I'm particularly interested in unanswered questions you have after reading these initial docs. --Beman

20 98

static_vector using aligned_storage
by Adam Wulkiewicz 18 Dec '12

18 Dec '12

Hi, I'm developing R-tree container for Boost.Geometry. To keep it short, there are containers of Values in leaf nodes. Those containers must have push_back() functionality. For static-size nodes I'm using a container based on boost::array. Unfortunately this means that default constructors of stored Values are called when the container is created. I'd like not to expect that Values have their default ctor implemented. I've implemented an alternative container using boost::aligned_storage. This is just a proof of concept. The code is available here: https://svn.boost.org/svn/boost/sandbox-branches/geometry/index/tests/stati… I've searched for this kind of container in Boost since I remember that someone proposed it some time ago but didn't find it anywhere. Is it released somewhere? Maby as a part of some library? If not, would you be so kind and see if my solution should work for any/most popular compiler/platform? I've tested it only on clang. To be specific, won't there be any problems with the memory aligmnent if I use this code for storage: boost::aligned_storage<sizeof(Value) * Capacity> m_storage; this for access: *(reinterpret_cast<Value*>(m_storage.address()) + i); and this for construction new (reinterpret_cast<Value*>(m_storage.address()) + i) Value(value); Regards, Adam

8 26

[range] Adapter to select class member
by Mark Snelling 17 Dec '12

17 Dec '12

Hi, I'm not sure if this has already been done but I have created a new Boost.Range adapter that will return a specified member variable of the class in the range, similar to the existing map_keys and map_values adapters. Would there be interest in this? For example consider the following code: #include <boost/range/adaptor/member.hpp> #include <boost/range/algorithm/copy.hpp> #include <boost/lexical_cast.hpp> #include <iostream> #include <vector> #include <string> struct A { int foo; std::string bar; }; int main(int argc, char* argv[]) { std::vector< A > input; for ( int i = 0; i < 10; ++i ) { A a; a.foo = i; a.bar = boost::lexical_cast< std::string >( i * 10 ); input.push_back( a ); } boost::copy( input | boost::adaptors::selected_member( &A::foo ), std::ostream_iterator< int >( std::cout, "," ) ); std::cout << std::endl; boost::copy( input | boost::adaptors::selected_member( &A::bar ), std::ostream_iterator< std::string >( std::cout, "," ) ); return 0; } Cheers, Mark

2 1

[crypto]not in https://github.com/boost-vault
by Jeff Flinn 16 Dec '12

16 Dec '12

It appears the crypto library that was in: http://www.boost-consulting.com/vault/index.php?action=downloadfile&filenam… Didn't get moved to https://github.com/boost-vault. Does anyone have access to the last vault incarnation? Thanks, Jeff

2 2

[release] permission to merge atomic and lockfree
by Tim Blechmann 16 Dec '12

16 Dec '12

hi all, apparently boost.atomic has been abandoned. i must admit, i'm very disappointed that the original author did hardly reacted neither on-list nor off-list. furthermore, it is blocking the release of boost.lockfree, so i'm volunteering to maintain this library. i'd rather see helge bahmann coming back and taking over responsibility for his code, but frankly, i lost all hopes that this is going to happen. iac, i'd like to get permission from the release managers to merge both atomic and lockfree to the release branch. thanks, tim

6 15

[GitHelp] Help desk support for developers moving to Git and modular Boost
by Beman Dawes 15 Dec '12

15 Dec '12

Documentation will aid developers moving to Git and modular Boost. See https://svn.boost.org/trac/boost/wiki/WikiStart#GitandModularBoost Beyond documentation, simply asking questions via a search engine works particularly well for Git. There is a vast amount of Git material available on the web, including some excellent YouTube videos. But documentation, web searches, and YouTube videos are not enough. Learning Git can be daunting - Git has more surface area than Subversion and it isn't obvious at first why some operations need to be done in a certain sequence or in a certain way or why they even need to be done at all. Two or three developers at C++Now mentioned that they became discouraged when they inadvertently got painted into a Git corner and couldn't find a way out. And even experienced git uses occasionally run into something they need human help with. This post proposes a virtual "Help Desk" to provide Boost specific answers to the inevitable questions that will come up during the transition to Git and modular Boost. The idea is that postings with at [GitHelp] subject tag will signal a request for help wrt Git or modular Boost. Anyone who can help should jump right in with a response. Comments? Suggestions? --Beman

3 2

[graph] A* search applied to knight's tour
by Dave Abrahams 15 Dec '12

15 Dec '12

Hi, I was just trying to work up an example for a class I'm teaching, to illustrate implicit graphs. The following shows how far I've gotten: https://gist.github.com/4153918 This is attempting to apply Warnsdorff's heuristic (choose the next move with the least out-degree) using A* search. I'm running into several problems having to do with the requirements of astar_search_no_init. In particular, the requirement that we can assign an index to every vertex is quite painful, since enumerating all the possible vertices in the search space is difficult. Any advice here? I suppose I could keep a real map and simply assign indices in the order vertices are encountered, but that seems pretty ugly to me. Any hints? -- Dave Abrahams BoostPro Computing Software Development Training http://www.boostpro.com Clang/LLVM/EDG Compilers C++ Boost

2 4