March 2017 - Boost - lists.boost.org

[gsoc2017] Apply for static_map
by Dobra Gábor 17 Mar '17

17 Mar '17

Hi all, I'm planning to participate to Boost GSOC, about static_map proposal. I'm Gábor Dobra, third-year student of Budapest University of Technology, Hungary, software engineering BSc. I've contributed to a few open-source libraries, I'm working as a C++ developer at a finance company. I'd like to contact a mentor of static_map (possibly Niall Douglas?) about my competency test. Thanks, Gábor

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[gsoc17] Apply for the ticket to Project static_map
by John Lee 17 Mar '17

17 Mar '17

Hello all, I’m John Lee from China, learning at BUPT, Beijing. I love coding, especially in C++. I am willing to contribute to Boost Community and applying for developing cool things with the community in GSOC 2017. As described in the requirement section, I suppose that I am well prepared :-) - I spent my 2016 in learning and practicing my Modern C++ (up to C++ 14, not 17 so far due to the poor support of compilers...) on both coursework and real products. - I’ve been contributing to some projects in C++ open-source communities in China, such as http://purecpp.org/ . - I’ve developed an open-source Header-Only, Strong-Typed, Compile-time Object Relation Mapping (ORM) in Modern C++, available at https://github.com/BOT-Man-JL/ORM-Lite (over-1000-line non-coursework library, first committed 5 months ago and iterated over time) (surprisingly meeting the requirements) lol - I also developed an toy Graphics Library on both Windows and X Window, but no longer maintain it. :-( It’s available at https://github.com/BOT-Man-JL/EggAche-GL/tree/x11 I’m a bit confused on some items on the main page of Boost GSOC 2017, and I will appreciate it very much if anyone could answer these questions: - I am very interested in generic/meta programming and willing to apply for Project static map. My question is should I still post a solution of the competency test of this project? - There are 3 suggested proposals on the main page. Are they the project we should do in GSOC 2017, or we can do other projects if applying for the ticket to a certain project of three? - How could I find a mentor if I have the ticket? Posting something like this or contact one on the email list? It’s my first year to attending GSOC, and the first time to work with the community internationally. Thanks for your help. ;-) Best Regards, John Lee Feel free to contact me :-) https://BOT-Man-JL.github.io/ -- View this message in context: http://boost.2283326.n4.nabble.com/gsoc17-Apply-for-the-ticket-to-Project-s… Sent from the Boost - Dev mailing list archive at Nabble.com.

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[release} 1.64.0 additional merge required
by Oliver Kowalke 17 Mar '17

17 Mar '17

Unforutnately I got an andditional pull reqeuest taht fixes an segmentation fault on ARM - https://github.com/boostorg/context/pull/47/files Do I get permission to merge to master? ty, Oliver

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Feedback request for Invariant Library idea
by Attila Szenczi 17 Mar '17

17 Mar '17

Hello! I am asking for some feedback if my library idea is good enough to be part of boost if it will meet the requirements. When i started this small utility lib i had 3 goals in my mind: - Write cleaner interfaces - Be safer with pre and post conditions - Eliminate redundant checks whenever possible at compile time The goal is to solve this problem for primitive types. *Example "bad" code:* void set_red_color(int red) { //Why the precondition is not visible on the interface? assert(red >= 0 && red <= 255); } *Example "good" code:* void set_red_color(bounded_i<0, 255> red) {} *Example "bad" code:* void foo(int bar) { assert(bar >= 0); } *Example "good" code:* void foo(positive_i bar) {} or void foo(lower_bounded_i<0> bar) {} Basically the main idea is to have an invariant_host class, which is customizable via policies: -* Invariant policy:* Define a static check() function which ensure the invariant. - *Fail policy: *Define a static trigger_assert function which is called when the invariant policy::check is failed. If the fail policy is disabled (constexpr bool flag), then the checks doesn't happen. Defining your own class looks like this: template<typename PrimitiveType> using my_type = invariant_host<PrimitiveType, default_fail, my_invariant<PrimitiveType>>; *Optimizations:* bounded_i<0, 50> bi (30); //trigger check bounded_i<0, 100> bi2(bi); //range check happens at compile time bounded_i<51, 52> bi3(bi1); //should be compile error bounded_i<0, 50> bi4(integral_constant<int, 10>); //check should happen compile time Things like operator+,-,*,/, bitwise operators etc can trigger checks. Tho alot of times it can be optimized away. For example adding 2 positive number should stay positive. C++20(?) contracts will be great, it will allow us to write cleaner interfaces, but i don't feel like it solve every issue i would like to solve. Do you think it would be a good addition to boost? I appreciate any feedback! Thank you very much! Attila Szenczi

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Advanced find() for associative containers
by Boris Rasin 16 Mar '17

16 Mar '17

I've written an improved version of find() for associative containers (in the form of a free function), and I need your help answering these two questions: 1. Will it be a useful addition to boost? 2. Where exactly should it fit in the boost? Public interface consists of a single free function template: template <typename C> auto find(C& c, const typename C::key_type& key); If element is found, return value evaluates to true and contains iterator to found element. If element is not found, return value evaluates to false and contains hint iterator for insert/emplace. Allowing one to do this: if (auto i = find(container, key)) { i->value_member(); container.erase(i); } And this: if (auto i = !find(container, key)) { container.insert(i, expensive_value_construction()); } The code is here: https://github.com/Boris-Rasin/find I've tested it with the following containers: std::map std::multimap std::unordered_map std::set std::multiset std::unordered_set boost::container::map boost::container::set boost::container::flat_map boost::container::flat_set boost::multi_index::ordered_unique boost::multi_index::ordered_non_unique boost::multi_index::hashed_unique boost::multi_index::hashed_non_unique boost::multi_index::ranked_unique boost::multi_index::ranked_non_unique Thanks for your comments and help.

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Fwd: Google Summer of Code
by Georgios Samaras 16 Mar '17

16 Mar '17

Dear all, my name is Georgios Samaras, a Masters student from NKUA, Greece. I am interested in the distance predicates <https://svn.boost.org/trac/boost/wiki/SoC2017#PROJECT1.Filteringofcomparedi….> of Boost Geometry, but I am flexible. I am attaching my CV in case anyone is interested. Here is my GitHub <https://github.com/gsamaras>, which demonstrates that I have experience in C++. Good luck with all your projects, Georgios Samaras

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Issue Tracker for Boost organization?
by Olaf van der Spek 16 Mar '17

16 Mar '17

Hi, Do we have an issue tracker for Boost 'organization' itself? I know we've got mailing lists and the steering committee but it's hard to track issues like that. -- Olaf

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[gsoc17] boost.uBLAS
by Leandro Raffo 16 Mar '17

16 Mar '17

Hi My name is Leandro, I'm a CS student at the University of Buenos Aires, and I'm interested in the uBLAS projects. I've already done the competency test and I was wondering who I should talk/send it to and who could be a possible mentor. Thanks

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Libc++ failures on linux
by Tom Kent 16 Mar '17

16 Mar '17

So I tried to add my first linux regression runner using libc++ with clang, and I'm seeing the following error saying it can't find <cstddef>: http://www.boost.org/development/tests/develop/developer/output/teeks99-02-… "clang++-3.9" -c -x c++ -Wno-c99-extensions -std=c++1z -stdlib=libc++ -O0 -g -fno-inline -Wall -g -m64 -DBOOST_ALL_NO_LIB=1 -DBOOST_CHRONO_STATIC_LINK=1 -DBOOST_CHRONO_THREAD_DISABLED -DBOOST_SYSTEM_NO_DEPRECATED -DBOOST_SYSTEM_STATIC_LINK=1 -DBOOST_TEST_NO_AUTO_LINK=1 -DBOOST_TIMER_STATIC_LINK=1 -I".." -o "/var/boost/run/results/boost/bin.v2/libs/accumulators/test/count.test/clang-linux-3.9~c++1z~lc/debug/link-static/count.o" "../libs/accumulators/test/count.cpp" In file included from ../libs/accumulators/test/count.cpp:6: In file included from ../boost/test/unit_test.hpp:18: In file included from ../boost/test/test_tools.hpp:17: In file included from ../boost/config.hpp:44: ../boost/config/select_stdlib_config.hpp:18:12: fatal error: 'cstddef' file not found # include <cstddef> ^ 1 error generated. However when I try to compile the following program on the same docker image (teeks99/boost-build:clang-3.9) // basic.cpp #include <cstddef> int main(int argc, char* argv[]) { size_t three = 3; return three; } with: $ clang++-3.9 -stdlib=libc++ -std=c++1z basic.cpp It works fine $ ./a.out $ echo $? 3 I can build this sample file fine with the whole command line shown above, so it doesn't seem to be one of the other options conflicting. Any thoughts on why boost code wouldn't be able to find this but some basic stuff would? One relevant detail, I'm building with clang 3.9, however the libc++ version that I'm using (ubuntu default) is the one that shipped with clang 3.7. That shouldn't preclude including a file! I also found a couple old threads with the same error, but never any good resolution. http://lists.boost.org/boost-testing/2012/07/7075.php http://lists.boost.org/boost-users/2012/11/76659.php Tom

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Re: [boost] [release] 1.64.0 closed for Beta
by Rene Rivera 15 Mar '17

15 Mar '17

On Tue, Mar 14, 2017 at 9:50 PM, Tom Kent <lists(a)teeks99.com> wrote: > > > On Tue, Mar 14, 2017 at 9:23 PM, Rene Rivera <grafikrobot(a)gmail.com> > wrote: > >> On Tue, Mar 14, 2017 at 6:09 PM, Tom Kent via Boost < >> boost(a)lists.boost.org> wrote: >> >>> >>> I tried building the latest snapshot from bintray, but it doesn't find >>> any >>> compiler when running `bootstrap.bat`. However running `boootstrap.bat >>> vc14.0` works, so something in bootstrap's lookup logic? >>> >> >> Which VSs did you have installed when you tried that? >> > > Everything from VS 2005 to VS2017. > In my Win10 setup I have VS 11, 12, 14, and 14.10.. And it seems to work for me. -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

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