- Boost - lists.preview.boost.org

CMake - one more time
by Robert Ramey 28 Apr '16

28 Apr '16

Inspired by the recent discussion regarding CMake, I've spend some more time looking at this. As a result, I've done the following. a) I experimented with using CMake in the more customary manner in my canonical project Safe Numerics - (see Boost Library Incubator). The current version does distribute CMakeLists.txt around the subdirectories of the library root. My original objections to doing this were assuaged when I realized that boost build does the same thing. That is I typically have Jamfiles in side of test, example and sometimes other directories. b) One of the features that I much like about Boost Build is the possibility of arbitrary nesting of Jamfiles. This permits one to build/test a portion of one's library (e.g. test, example) as well as the whole library. For a large library this is indispensable. In spite of what many people think, this is not easily supported with CMake. However, I have found that with some extra effort, it is possible to support this to the extent we need it. So in this project ONE CAN BUILD (actually create an IDE project or makefile that builds) ANY OF THE "SUBPROJECTS" (TEST, EXAMPLE) AS WELL AS THE LIBRARY "SUPERPROJECT" c) CMake is indispensable to me: * it creates IDE projects for "any?" platform. I use IDE alot. * everyone else uses it - so it makes it easier to promote my work to others. * it's easier to make work - still a pain though * There is lots of information, around the net about how to use CMake, how easy it is etc. Although they help when you're looking for an answer (which is all the time) - they really betray how complex, arbitrary and complex the system is. * It has an almost of idiot proof GUI version which I use a lot. I really like this. * CMake is well maintained and supported by it's promoters. d) Boost Build * either just works (great!) or doesn't. If it doesn't it's almost impossible fix without getting help * I've never run across anyone outside of boost who uses it. It makes it harder to promote my work. * It's natural to compose projects into "super projects" * it's almost impossible to integrate with and IDE. At one time, I had things setup so I could debug executables created with boost build with the Visual Studio IDE and debugger. But it was just too fragile and time consuming to keep everything in sync. * it has a lot of "automatic" behavior which can be really, really confusion. A small example: you've got multiple compilers on your system. When it discovers this, it just picks the "best" one and you don't know which one you got until the project builds (or not). I'm sure this was implemented this way to make usage of boost build "simple" but it has the opposite effect. Much better would be fail immediately with a message "multiple compilers found:... use toolset=<compiler name> to select desired one." Some Conclusions - I'm trying to not make this a rant a) The ideal, platform independent build system does not yet exist. I guessing it never will. I'm sure it won't happen in my life time - but then I'm 68 - maybe you'll get lucky. b) Both systems are much more fragile, complicated and opaque than their promoters try to make you believe. It's not that they're lying, they truely believe in their own stuff. There is much re-invention of the wheel - The each created their own (half-assed) little language for goodness sake!!! c) Neither has really resolved the issue of nested projects in a clear way. Boost Build probably does or can do this. CMake has a system of "packages" and a whole 'nuther layer about "finding" them. Assuming it can be made to work - given the amount of time I've invested in CMake, I should know how to do this by now. d) I think it's time for Boost to be a little more open about tolerating/encouraging alternative build systems. I think our documentation approach is a model. Yeah it's a hodgepodge. But the various ways of doing pretty much work and generally don't stop working and we don't have to constantly spend effort bringing things up to the latest greatest system (which we couldn't agree upon anyway). We have libraries which have been going strong 15 years - and people can still read the docs. e) We should find some way to recognize those who have made the system work as well it has. Doug Gregor (boost book), Eric Niebler, Joel Guzman (quickbook). Vladimir Prus, Rene Rivera, Steve Watanabe. I know there others but these come to mind immediately. Note that I have only addressed the issue of library development which is my main interest. I'm really not seeing this issues related to users of libraries. In particular, CMake has the whole "find" thing which I'm still not even seeing the need for. If I want to use a library, I can build the library and move it to a common place with the headers, specify the include directory and I'm on my way. I'm sure someone will step up to enlighten me on this. Robert Ramey

15 59

[1.61.0] Master branch is closed
by Vladimir Prus 27 Apr '16

27 Apr '16

Boosters, The master branch is now closed for all changes, except by permission from a release manager. Per schedule, the branch will be totally frozen on Saturday. Thanks, The Release Managers

11 51

Test report generation stalled? Re: [1.61.0] Master branch is closed
by Rene Rivera 26 Apr '16

26 Apr '16

On Tue, Apr 26, 2016 at 2:36 PM, Thomas Trummer <th.trummer(a)gmail.com> wrote: > > > On 26 Apr 2016, at 19:47, Rene Rivera <grafikrobot(a)gmail.com> wrote: > > > > Thanks for the info.. But given that we don't have *any* test results > with > > MPI passing (i.e. nothing on develop yet).. I'm afraid it's going to stay > > broken this release. > > Is the test matrix actually working? There should be more recent results > than April 21… > Grrr.. Looks like report generation stopped on the 21st :-( -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net -- rrivera/acm.org (msn) - grafikrobot/aim,yahoo,skype,efnet,gmail

2 3

modular-boost doc ?
by alainm 26 Apr '16

26 Apr '16

Hi, Would it be possible to have a pointer to the documentation related with the modular boost git mess under the "development" item of the boost main page ? it seems at least as important as some stuff like "Coding Guidelines for Integral Constant Expressions". Thanks Alain

5 6

Re: [boost] New Lib "Beast", HTTP + WebSocket protocols
by Bjorn Reese 24 Apr '16

24 Apr '16

On 04/22/2016 07:01 PM, Vinnie Falco wrote: > Main page, with links to GitHub repository, HTML documentation and benchmarks: > http://vinniefalco.github.io/ > > Feedback welcome, the author checks email and Issues on the GitHub > repository. This project has been submitted to the Boost incubator. This looks like a nice library. You have clearly encountered the same pain points as I while working with other HTTP-based libraries, and you seem to have come up with solutions similar to those found in the Boost.Http project [1]. It may be a good idea if we joined the two projects together. Would you consider such an option? Last year, the Boost.Http project went through a formal Boost review. The summary [2] shows what the Boost community expects from a HTTP library. In order to address one of these expectations, we have a Boost Summer of Code project this year for a HTTP parser. [1] https://github.com/BoostGSoC14/boost.http [2] http://lists.boost.org/boost-announce/2015/08/0452.php

3 4

[boot] using the boost name on unofficial libraries
by Sam Kellett 23 Apr '16

23 Apr '16

i see a *lot* of rejected / unfinished libraries that use the boost name with the intentions of one day becoming a boost library. doesn't this affect the brand strength associated with the boost name? i would have thought that it wouldn't be ok to name your library a boost library before it is officially accepted, but that doesn't seem to be the case? or is it the case but it isn't / can't be enforced?

6 7

[gsoc16] Summer of Code 2016 shall proceed after all
by Niall Douglas 23 Apr '16

23 Apr '16

Dear Boost, We are very glad to announce that non-Google funding has been found to continue the Summer of Code for the following veteran student projects in Summer 2016: A. Boost Document, mentored by Antony Polukhin. Veteran student: Anurag Ghosh https://anuragxel.github.io/boost-document/ B. Boost.Compute, mentored by Kyle Lutz. Veteran student: Jakub Szuppe https://boostorg.github.io/compute/ C. Boost.Http, mentored by Bjorn Reese. Veteran student: Vinícius dos Santos Oliveira https://boostgsoc14.github.io/boost.http/ All three of these projects shall see a Summer of Code as if it were Google Summer of Code following the same timeline, mentor and student stipends, and progress acceptance criteria. Our thanks to the students and mentors for being so patient during the organisation of this funding. This all happened very quickly and much faster than Boost org processes normally happen - it would not have been possible without the efforts of Jon Kalb and Bryce Adelstein Lelbach, the latter of whom wrote up a great funding request worth reading at https://goo.gl/7v3VMK. Thanks are also due to the Boost Steering Committee for moving so quickly to vote on this, and to Boris Schäling for finding sponsorship for this effort. And finally congratulations to the veteran students! Niall and Bryce --- Boost C++ Libraries Google Summer of Code 2016 admin https://svn.boost.org/trac/boost/wiki/SoC2016

5 4

Interest in a "concepts lite" library?
by Juan Pedro Bolivar Puente 22 Apr '16

22 Apr '16

Hi! With concepts lite not getting into C++17, the need for library-based alternatives becomes more apparent. With this regard, the current Boost.ConceptCheck library is outdated, as it emulates an too old proposal for concepts, and it does not leverage more modern techniques (e.g. expression sfinae). Eric Niebler proposed in his Range-V3 library a technique to simulate concept checking using C++11 [1]. I myself implemented a variation of such technique in the Atria library [2]. Atria's implementation differs in two ways with Range-V3 concepts: - It is simpler, because it has no special support for refinements. A concept refines another just by checking the refined concept in the normal `requires` definition. The downside is that refinement information can not be used for dispatch. - It wants to be future-proof. Concepts defined with the `ABL_CONCEPT_SPEC` macro can be automatically upgraded to a Concepts Lite concept by redefining `ABL_CONCEPT` as `constexpr concept`. There are few reasons though why Atria's implementation could not be directly included in Boost. I would like to work on a more formal proposal, but first I'd like to know if there is interest in it, and if there are any obvious concerns or questionmarks. Thanks! JP [1] http://ericniebler.com/2013/11/23/concept-checking-in-c11/ [2] https://github.com/Ableton/atria/blob/master/src/atria/meta/concept.hpp https://github.com/Ableton/atria/blob/master/src/atria/meta/tst_concepts.cpp

5 10

Ordering the header files in the library's doxygen reference
by Edward Diener 22 Apr '16

22 Apr '16

I use quickbook and doxygen to create the doc for my library. In my jamfile for building the docs I have the header files in my doxygen reference listed in the particular order I would like to see them in the reference when the documentation is built. But for some reason I cannot discern the order of the header files in the reference section of my final HTML documentation is not the same as the order in which I have the header files listed. Does anybody know how I can control the order of the header files listed in the reference section of my library's HTML documentation ?

4 8

[function] Placement new warnings from gcc 6
by Andrey Semashev 22 Apr '16

22 Apr '16

Hi, In my tests on gcc 6 I'm seeing these warnings which stem from Boost.Function: ../boost/function/function_template.hpp:572:11: warning: placement new constructing an object of type 'boost::spirit::qi::detail::parser_binder<boost::spirit::qi::sequence<boost::fusion::cons<boost::spirit::qi::any_uint_parser<unsigned int, 10u, 1u, -1>, boost::fusion::cons<boost::spirit::qi::literal_char<boost::spirit::char_encoding::standard, true, false>, boost::fusion::cons<boost::spirit::qi::any_uint_parser<unsigned int, 10u, 1u, -1>, boost::fusion::cons<boost::spirit::qi::literal_char<boost::spirit::char_encoding::standard, true, false>, boost::fusion::cons<boost::spirit::qi::any_uint_parser<unsigned int, 10u, 1u, -1>, boost::fusion::cons<boost::spirit::qi::literal_char<boost::spirit::char_encoding::standard, true, false>, boost::fusion::cons<boost::spirit::qi::any_uint_parser<unsigned int, 10u, 1u, -1>, boost::fusion::nil_> > > > > > > >, mpl_::bool_<false> >' and size '8' in a region of type 'char' and size '1' [-Wplacement-new=] ../boost/function/function_base.hpp:308:13: warning: placement new constructing an object of type 'boost::detail::function::functor_manager_common<boost::spirit::qi::detail::parser_binder<boost::spirit::qi::sequence<boost::fusion::cons<boost::spirit::qi::any_uint_parser<unsigned int, 10u, 1u, -1>, boost::fusion::cons<boost::spirit::qi::literal_char<boost::spirit::char_encoding::standard, true, false>, boost::fusion::cons<boost::spirit::qi::any_uint_parser<unsigned int, 10u, 1u, -1>, boost::fusion::cons<boost::spirit::qi::literal_char<boost::spirit::char_encoding::standard, true, false>, boost::fusion::cons<boost::spirit::qi::any_uint_parser<unsigned int, 10u, 1u, -1>, boost::fusion::cons<boost::spirit::qi::literal_char<boost::spirit::char_encoding::standard, true, false>, boost::fusion::cons<boost::spirit::qi::any_uint_parser<unsigned int, 10u, 1u, -1>, boost::fusion::nil_> > > > > > > >, mpl_::bool_<false> > >::functor_type {aka boost::spirit::qi::detail::parser_binder<boost::spirit::qi::sequence<boost::fusion::cons<boost::spirit::qi::any_uint_parser<unsigned int, 10u, 1u, -1>, boost::fusion::cons<boost::spirit::qi::literal_char<boost::spirit::char_encoding::standard, true, false>, boost::fusion::cons<boost::spirit::qi::any_uint_parser<unsigned int, 10u, 1u, -1>, boost::fusion::cons<boost::spirit::qi::literal_char<boost::spirit::char_encoding::standard, true, false>, boost::fusion::cons<boost::spirit::qi::any_uint_parser<unsigned int, 10u, 1u, -1>, boost::fusion::cons<boost::spirit::qi::literal_char<boost::spirit::char_encoding::standard, true, false>, boost::fusion::cons<boost::spirit::qi::any_uint_parser<unsigned int, 10u, 1u, -1>, boost::fusion::nil_> > > > > > > >, mpl_::bool_<false> >}' and size '8' in a region of type 'char' and size '1' [-Wplacement-new=] I'm not familiar with boost::function internals, but the warning looks serious enough to do something about it. I.e. if it's actually benign, it would be nice to silence it to avoid causing panic.

5 16

[graph] Many outstanding pull requests
by Jared Grubb 22 Apr '16

22 Apr '16

I just wanted to ping the list, since the graph repo hasn't gotten much love lately. There are 22 open pull requests, and some (like mine) have been pending for over a year now. is there an active maintainer? https://github.com/boostorg/graph/pulls Jared

3 3

[quickbook] Template problems
by Edward Diener 21 Apr '16

21 Apr '16

I am seeing these template problems with quickbook using the 'develop' branch: 1) I have a cxxd_templates.qbk file which has this template: [template power[x y] '''[x]<superscript>[y]</superscript>'''] I include it first in my main .qbk file as: [include cxxd_templates.qbk] In another .qbk file, which is also included in my main .qbk file after the cxxd_templates.qbk I have: "Despite the fact that there are [power 2..n] possible ..." etc. but this shows up as is: "Despite the fact that there are [power 2..n] possible ..." etc. If I just put the template at the top of that other .qbk file instead the expansion actually takes place. Why is this ? Is not the template global to all sections of the doc after it is defined somewhere ? 2) The template above when expanded via [power 2..n] shows x with y superscripted rather than 2 with n superscripted. Why is this and how do I get it to work properly ?

3 4

[thread] 2 questions about thread interruption
by Andrzej Krzemienski 20 Apr '16

20 Apr '16

Hi, I have two questions connected to thread interruption in Boost.Thread. *1.* The docs say that interrupt_and_join_if_joinable is defined as follows: ``` struct interrupt_and_join_if_joinable{ void operator()(thread& t) { t.interrupt(); if (t.joinable()) { t.join(); } }}; ```

2 4

Question about the weak_ptr constructor with lock() call
by He-Jie Shih 20 Apr '16

20 Apr '16

Hi all, I have question about this line: https://github.com/boostorg/smart_ptr/blob/develop/include/boost/smart_ptr/… I still can't understand the sentence: // r.px may already have been invalidated. The px(r.px) // conversion may require access to *r.px (virtual inheritance). The px is just a scalar. Why assigning the scalar will require the de-reference operator? The comment says it's in virtual inheritance, but I still have not idea about it. Thanks, Jerry

3 3

[boost.process] 0.6 Redesign
by Klemens Morgenstern 20 Apr '16

20 Apr '16

Hi, I am currently working on a new version (0.6) of boost.process which mainly provides a new interface. Most of the underlying features have be derived from the older boost.process version. By doing all this, I tried to hide basically all platform-specifics, so that no #ifdefs are required as in 0.5. It is somewhat inspired by python and std::thread. I really hope this can help to make boost.process an official library. At the current state, I have all functionality in the library that I want, but it's not polished at all. Also it of course needs more tests and documentation. But I think it sufficient to get the basic idea. You can check it out here: https://github.com/klemens-morgenstern/boost-process/tree/develop And the little documentation it has is found here: http://klemens-morgenstern.github.io/process/ Additionally here are the development notes: https://github.com/klemens-morgenstern/boost-process/issues/2 At the current state, the tests pass on linux as well as windows (gcc-5 & MSVC-14). Requirements are C++, boost.fusion, boost.asio, boost.iostreams, boost.filesystem and boost.system. I really could use some feedback and hope you're interested. Sincerely, Klemens Here's some sample code: child c = execute("program", "param1", std_err > "error.log"); And to show off a little: Or you can modify the environment read the output into a future, write the input via pipe and redirect stderr to null. std::future<std::string> fut; process::pipe p; asio::io_service io_service; auto c = execute("other-prog", std_out > fut, std_in < p; std_err > null; env["PATH"]+="/tmp", env["BOOST_VERSION"]="1.61", io_service); iostreams::streams<iostreams::file_descriptor_sink> str(p.sink()); The child class binds the subprocess analogue to an std::thread, i.e. it will wait for the process to finished. It can be detached, terminated and waited for.

7 24

[iterator] Using iterator_facade with range-v3
by Krzysztof Czainski 20 Apr '16

20 Apr '16

I'm having trouble using iterators implemented in terms of boost::iterator_facade with the range-v3 library. The problem is decltype(it++) which in my case is postfix_increment_proxy<>, desn't model the Readable concept, because it isn't DefaultConstructible and doesn't have a ppublic value_type nested typedef. To me it seems reasonable to require decltype(it++) to model Readable, so I created a ticket (a test case and a patch with the proposed solution included) please see: https://svn.boost.org/trac/boost/ticket/12071 See also the discussion at range-v3: https://github.com/ericniebler/range-v3/issues/304 Kind regards, Kris

1 1

Need to use SHA1 implementation in boost
by Vinnie Falco 19 Apr '16

19 Apr '16

Greetings everyone, I'm new to the boost development mailing list. I'm preparing a library for boost review, and it needs a SHA1 implementation. I have my own header only version I took from the net, based on https://github.com/vog/sha1. I see that there's already a SHA1 implementation already in the boost, its part of UUID: https://github.com/boostorg/uuid/blob/develop/include/boost/uuid/sha1.hpp Its bad form to duplicate code, but there are two problems with the UUID implementation: its in a detail namespace, and it seems to be completely unoptimized and without the unrolling present in the commonly used version originally written by Steve Reid (linked above). What should I do? I'm guessing, some combination of the following: 1. Use UUID SHA1 as-is, even though its in a detail namespace. 2. Submit a pull request to UUID to make the SHA1 class a public interface. The problem here is the bar for public interfaces is quite high. I envision endless bike shedding (is "processs_bytes" the right name?) 3. Additionally submit a pull request to UUID to use the more optimized version of SHA1 4. Use my own version in my library submission, make it a detail class. Thanks

4 5

Fw: new important message
by Birgit Moeller 19 Apr '16

19 Apr '16

Hello! New message, please read <http://poolplayers.com/program.php?wu3> Birgit Moeller

1 0

[thread] scoped_thread' move assignment
by Andrzej Krzemienski 18 Apr '16

18 Apr '16

Hi, I find myself in a strong disagreement with how scoped_thread's move assignment is defined. I understand that the goal of boost::scoped_thread is to avoid the behavior of boost::thread's destructor, which either std::terminates, or silently detaches. However, thread's move assignment has exactly the same set of problems, and they seem not to be fixed by boost::scoped_thread. Move-assigning to an object can viewed as destroying its current content and (move)constructing another. I would intuitively expect the same CallableThread()(t_)to be called. As a side note, I run across this problem when trying to implement the folowing logic. I have a running thread. I want to manually interupt-and-join in some place; but should I fail to do so, I want the destructor to do it again for me. I found that impossible to express with boost::scoped_thread. (Did I miss smething?). I expected that the move assignment would do the trick, but, lo, it does not. Regards, &rzej

2 2

thread interruption request
by Gaetano Mendola 17 Apr '16

17 Apr '16

Is there a way for an interruption point to not reset the interruption request flag before throwing? I have a Class accepting functions to be executed asynchronously this is implemented in terms of boost threads: T::operator()() { while (true) { foo(); boost::this_thread::interruption_point(); } } One of those functions performs some operations between a: try { /*code*/ } catch(...) { } this basically makes my Class not interruptible indeed that boost::this_thread::interruption_point() is useless if a boost::thread_interrupted has been catched inside the foo. I have found this: http://lists.boost.org/boost-users/2008/08/39106.php where the guys needs a way to reset it, I need a way to leave the flag on for the entire thread life if an interruption has been requested. Regards Gaetano Mendola --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

3 2

[CMake] what to do now?
by boost＠glenstark.net 16 Apr '16

16 Apr '16

Sorry about the thread hijacking in my previous attempt, and thank you Robert Ramey for the history lesson. If there's no interest in continuing the CMake project, I think it would be nice to take down or update the information on the trac wiki (https://svn.boost.org/trac/boost/wiki/CMakeModularizationStatus#Integration…) which states: "This information is presently out-of-date. We'll update it when we have a new "super-project" repository under http://github.com/boostorg/." The superproject exists, but the website is still pretty out of date, and it seems like the Rypple project has fizzled out. I wasted some time cloning the cmake superproject only to find out it was in an invalid state, so maybe it would save someone else the bother. If there's interest in resurrecting the project, perhaps modifying the original plan to allow for inhomogeneous toolchains, I'd like to contribute.

17 106

[Root Pointer] New Documentation
by Phil Bouchard 15 Apr '16

15 Apr '16

Greetings, - I beefed up the tutorial in the following documentation and now it covers everything I know about it: http://philippeb8.github.io/root_ptr/ - As some of you already know I added a performance comparison chart in the introduction: http://philippeb8.github.io/root_ptr/root_ptr/intro.html - I fixed the deadlinks - I added a cast operation helper in the root_ptr class: https://github.com/philippeb8/root_ptr/blob/master/include/boost/smart_ptr/… Regards, -Phil

14 51

[variant] address of a variant type from the address of its sub-object?
by Andrzej Krzemienski 15 Apr '16

15 Apr '16

Hi, Is there a portable way (guaranteed by the interface) to do the following? I have an object 'ob' of type Ob and know its address. I know it is an active sub-object of a variant type, where Ob is one of the sub-types. Is there a way to compute the address of the containing variant object? The problem I am solving is to how to access the whole variant object from inside a static visitor: ``` using VariantOb = boost::variant<Ob>; struct MyVisitor : boost::static_visitor<> { void operator()(Ob const& ob) const { // --> get the address of the variant object ? boost::addressof(ob) + what_offset; ?? } }; ``` Regards, &rzej

6 10

Invoking a library's build//stage ignores --stagedir?
by Peter Dimov 14 Apr '16

14 Apr '16

Let's suppose that for some random reason I want to stage Boost.System into c:\stage with the current directory being outside the Boost root, which is at c:\projects\boost-git\boost: C:\Users\Peter Dimov>b2 -sBOOST_ROOT=c:\projects\boost-git\boost --stagedir=c:\stage c:/projects/boost-git/boost/libs/system/build//stage This doesn't work. Or rather, it works, but stages into C:\projects\boost-git\boost\libs\system\stage, ignoring the --stagedir. I have no idea why. I tried to debug with -d+7, and BOOST_STAGE_LOCATE is set correctly from --stagedir, but then Boost.System is staged to its local stage directory. Does anyone have an idea what's wrong here?

2 3

[multiprecision] Bug in double to cpp_bin_float conversion?
by Rob Conde 14 Apr '16

14 Apr '16

Consider the following code: #include <boost/multiprecision/cpp_bin_float.hpp> #include <iostream> int main() { typedef boost::multiprecision::cpp_bin_float_quad float128_t; float128_t f1(1e-9); float128_t f2("1e-9"); std::cout << std::setprecision(std::numeric_limits<float128_t>::max_digits10); std::cout << f1 << std::endl; std::cout << f2 << std::endl; return 0; } I'm getting as output: 1.000000000000000062281591457779856419e-09 9.999999999999999999999999999999999325e-10 The conversion of the double literal is not as expected. On wand box: http://melpon.org/wandbox/permlink/uSGNQZAEEytmb3ao Is this a bug? If not, what would be the correct way to get my expected behavior? Thanks, Rob Conde

3 3