June 2014 - Boost - lists.preview.boost.org

Moving utility/declval.hpp to type_traits
by Peter Dimov 05 Jun '14

05 Jun '14

I was going to move utility/declval.hpp to type_traits, but type_traits has many unmerged changes. Since the contents of declval.hpp are currently the same in master and develop, replaying its history on top of type_traits:master and type_traits:develop should not affect any later merges, but still, I always prefer to do this when master and develop are identical, so thought I'd ask first. John?

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[config] intel-linux with -fno-rtti doesn't set BOOST_NO_RTTI...
by Peter Dimov 05 Jun '14

05 Jun '14

... and BOOST_NO_TYPEID. I can see in the config_info output that __RTTI (without the option) is 1, so maybe the check belongs in common_edg.hpp.

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[core] Move underlying_type to type_traits?
by Andrey Semashev 04 Jun '14

04 Jun '14

While documenting and cleaning up scoped_enum.hpp I factored out the underlying_type trait to a separate header. Mostly, because I didn't want to #include <type_traits> in scoped_enum.hpp. boost::underlying_type should be equivalent to std::underlying_type, except that it also supports emulated scoped enums. Perhaps boost/core/underlying_type.hpp should be moved to Boost.TypeTraits?

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Looking for git help for Boost releases
by Marshall Clow 04 Jun '14

04 Jun '14

I’m trying to figure out tooling for making boost releases. One of the missing pieces that we had in SVN was “svn export”, which let you check out a particular branch/revision to a local folder, w/o any of the SVN infrastructure (such as .svn folders). It also let you set the line endings of the files, so I could make a release with Windows line endings on a non-windows computer. The command that I used was: svn export --non-interactive --native-eol XXX -r YYY, https://svn.boost.org/svn/boost/branches/release ZZZ where: XXX was line ending that I wanted (either CRLF for windows or LF for unix) YYY was the revision that I was interested in (usually HEAD) ZZZ was the destination for the export How can I do something like this for git? I’ve looked at “git archive”, and that’s something like what I want, but it doesn’t handle sub-projects. There are a few scripts around that claim to do “git archive over sub-projects”, but I haven’t found one that works with our set up, and none of them let you modify the line endings for (some of) the files as part of the process. Any ideas? Suggestions? Pointers? Thanks in advance. — Marshall

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[Predef] Splitting a version number into components
by Arindam Mukherjee 04 Jun '14

04 Jun '14

Given some vendor version number, is there any macro in Predef to split it into major, minor and patch components? I noticed the macros BOOST_PREDEF_MAKE_* macros. What do these macros help achieve which BOOST_VERSION cannot? Thanks, Arindam

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[atom]
by Christian Henning 04 Jun '14

04 Jun '14

There two compiler errors ( both x86 and x64 ) when building the current master. c:\boost\boost/atomic/detail/ops_msvc_x86.hpp(860) : error C2065: 'order' : undeclared identifier c:\boost\boost/asio/detail/impl/socket_ops.ipp(534) : error C2065: 'SO_UPDATE_CONNECT_CONTEXT' : undeclared identifier I'm using Visual Studio 2013 on Window. The complete output ( x86 release ) is here: http://pastebin.com/raw.php?i=KgnJgWGQ Regards, Christian

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[Modularization] Levels classification
by Vicente J. Botet Escriba 04 Jun '14

04 Jun '14

Hi, could we add a page listing the modules by levels following this rule * A module is in Level 0 if it doesn't depends on other modules * A module is in Level 1 if it depends only on modules at level 0 * A module is in Level N+1 if it depends only on modules at level N or lower levels We have now the following modules that satisfy the rule Moduler levels Level 0 : Config Predef Preprocessor Level 1 : Assert Static Assert Level 2 : Core Level 3 : Utility (After moving string_ref out (???), moving iterator to Core and generator_iterator to Iterator Peter, could you update the Dependency report? Could your report assign a level following this rule and show the modules with an assigned level? Best, Vicente

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[multiprecision] General/design query about which conversions should be implicit/explicit
by John Maddock 04 Jun '14

04 Jun '14

Folks, I have an open bug report https://svn.boost.org/trac/boost/ticket/10082 that requests that conversions from floating point to rational multiprecision-types be made implicit (currently they're explicit). Now on the one hand the bug report is correct: these are non-lossy conversions, so there's no harm in them being implicit. However, it still sort of feels wrong to me, the only arguments against I can come up with are: 1) An implicit conversion lets you assign values such as 0.1 to a rational (which actually leads to 3602879701896397/36028797018963968 not 1/10), where as making the conversion explicit at least forces you to use a cast (or an explicit construction). 2) Floating point values can result in arbitrarily large integer parts to the rational, effectively running the machine out of memory. Arguably the converting constructor should guard against that, though frankly exactly how is less clear :-( Does anyone else have any strong views or insights into this? Thanks in advance, John.

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[GSoC][MPL11] Post C++Now update
by Louis Dionne 04 Jun '14

04 Jun '14

Dear Boost, A lot happened during the past week in Aspen; the goal of this message is to summarize insights, changes and feedback received wrt MPL11. The slides of the presentation are available at [1]. The second part of the presentation is especially relevant to get an overview of the designs considered so far. Merging the MPL and Fusion -------------------------- After discussing the issue several times during the week, I (and others) think it might be possible to merge Fusion and the MPL into a single library. I am currently trying to write a library that does that. Since this constitutes a large reorientation, I created a new repository which is available at [2]. Those with interest should consider subscribing to the repository to be updated as I make progress. Iterator-free design -------------------- I was a bit anxious that people would complain about this, but the contrary happened. Nobody complained and some people expressed support. This design aspect will stay as-is. Request for guinea pigs ----------------------- I am looking for people with hardcore C++1y metaprogramming needs who will be willing to test the library I come up with (MPL11 or MPL + Fusion merge). I also need to see use cases for the library, so please reply even if you are not willing to test. Roadmap ------- Finish exploring the design space. If it turns out that we can merge the MPL and Fusion, then I'll be working on that for a while. If I find that this is not possible or not a good idea, I'll go back to my initial GSoC planning. In both cases, I hope to have a library in the incubator by the end of the summer. Also, this new roadmap is approved by my mentor. Feel free to reply with questions and/or comments. Regards, Louis [1]: http://ldionne.com/mpl11-cppnow-2014 [2]: http://github.com/ldionne/hana

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[master] Building boost 1.56 - only 4 libs are built
by Christian Henning 04 Jun '14

04 Jun '14

When I execute the following command usually all libs are built: bjam -j8 --toolset=msvc --without-mpi variant=debug link=static runtime-link=shared define=_CRT_NONSTDC_NO_DEPRECATE define=_CRT_SECURE_NO_DEPRECATE define=_SCL_SECURE_NO_DEPRECATE define=BOOST_REGEX_MATCH_EXTRA stage > log_x86_debug.txt But on the current master only three libs are built or copied into my stage folder. libboost_container-vc120-mt-gd-1_56.lib libboost_context-vc120-mt-gd-1_56.lib libboost_exception-vc120-mt-gd-1_56.lib libboost_prg_exec_monitor-vc120-mt-gd-1_56.lib Is my command incorrect? I have been using it for many years. Regards, Christian

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