- Boost - lists.preview.boost.org

Final Notice: BinTray is shutting down 1-May (that's SATURDAY)
by Marshall Clow 07 May '21

07 May '21

Bintray is “sunsetting” on the 1st of May. At that time, you will be unable to download boost releases from there. Before that time, their service will be occasionally interrupted. The web site has been updated, all the download links now refer to https://boostorg.jfrog.io/artifactory/main/release/ <https://boostorg.jfrog.io/artifactory/main/release/> Example: Instead of downloading from: https://dl.bintray.com/boostorg/release/1.76.0/source/boost_1_76_0.tar.gz <https://dl.bintray.com/boostorg/release/1.76.0/source/boost_1_76_0.tar.gz> You should download from: https://boostorg.jfrog.io/artifactory/main/release/1.76.0/source/boost_1_76… <https://boostorg.jfrog.io/artifactory/main/release/1.76.0/source/boost_1_76…> This applies to all releases from 1.63.0 onward (The pre-1.63 releases are still hosted at SourceForge) — Marshall

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[GSoC] - Boost.Multiprecision Quad Double
by Γιάννης Γονιδέλης 07 May '21

07 May '21

Hello! Christopher, Unfortunately, due to some urgent issues I won't be able to contribute during the summer. Thus, in case you have been considering picking me I would ask you to make a new choice. Apologies, Giannis

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Google Summer of Code 2021
by David Bellot 05 May '21

05 May '21

Hi Boost community, The mentors are now finalizing their selection of the students. Google has been very generous this year with the number of slots we were allocated and we are happy to say that we will again have a nice (and large) team of incredible students developing with us this summer (or winter if you're down under like me). Stay tuned because we will announce the list of projects very soon. Best regards, David

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[Math] Standalone beta release
by John Maddock 05 May '21

05 May '21

Just a heads up that Boost.Math now has a (beta) standalone release at https://github.com/boostorg/math/releases/tag/v1.76-standalone-beta We would very much appreciate any interested parties giving it a whirl and reporting back. With many thanks to Matt Borland and Nick Thompson for making this possible! Best, John Maddock. -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

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wrong result in complex pow
by Gero Peterhoff 03 May '21

03 May '21

Hello, the pow-function pow(scalar, complex) in boost/math/cstdfloat/cstdfloat_complex_std.hpp get wrong result. Current implementation: inline complex<BOOST_CSTDFLOAT_EXTENDED_COMPLEX_FLOAT_TYPE> pow(const BOOST_CSTDFLOAT_EXTENDED_COMPLEX_FLOAT_TYPE& x, const complex<BOOST_CSTDFLOAT_EXTENDED_COMPLEX_FLOAT_TYPE>& a) { return std::exp(a * std::log(x)); } I think that's correct: inline complex<BOOST_CSTDFLOAT_EXTENDED_COMPLEX_FLOAT_TYPE> pow(const BOOST_CSTDFLOAT_EXTENDED_COMPLEX_FLOAT_TYPE& x, const complex<BOOST_CSTDFLOAT_EXTENDED_COMPLEX_FLOAT_TYPE>& a) { return std::exp(a * std::log(complex<BOOST_CSTDFLOAT_EXTENDED_COMPLEX_FLOAT_TYPE>(x))); } regards Gero

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Cannot build 1.76.0 for Windows (wrong path to compiler)
by Andreas Tscharner 03 May '21

03 May '21

Hello World, I try, according to the "Get started guide" >bootstrap.bat in the main boost directory. I get an error, because "C:\Program Files(x86)" ... contains a space and is not double quoted. So I replace all set "B2_CXX=%CXX% ..." with set "B2_CXX="%CXX%" ..." in tools\build\src\engine\config_toolset.bat After that I have the following problem: D:\Projects\development\QUARTIS-related\boost>.\bootstrap.bat Building Boost.Build engine LOCALAPPDATA=C:\Users\ATs\AppData\Local Found with vswhere C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise Found with vswhere C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise Call_If_Exists "C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\Common7\Tools\..\..\VC\Auxiliary\Build\vcvarsall.bat" AMD64 ********************************************************************** ** Visual Studio 2019 Developer Command Prompt v16.9.4 ** Copyright (c) 2021 Microsoft Corporation ********************************************************************** [vcvarsall.bat] Environment initialized for: 'x64' ### ### Using 'vc142' toolset. ### D:\Projects\development\QUARTIS-related\boost\tools\build\src\engine>"C:/Program Files (x86)/Microsoft Visual Studio/2019/Enterprise/VC/Tools/MSVC/14.27.29110/bin/Hostx64/x64/cl.exe" /nologo /MP /MT /TP /Feb2 /wd4996 /O2 /GL /EHsc -DNDEBUG builtins.cpp class.cpp command.cpp compile.cpp constants.cpp cwd.cpp debug.cpp debugger.cpp execcmd.cpp execnt.cpp filent.cpp filesys.cpp frames.cpp function.cpp glob.cpp hash.cpp hcache.cpp hdrmacro.cpp headers.cpp jam.cpp jamgram.cpp lists.cpp make.cpp make1.cpp md5.cpp mem.cpp modules.cpp native.cpp object.cpp option.cpp output.cpp parse.cpp pathnt.cpp pathsys.cpp regexp.cpp rules.cpp scan.cpp search.cpp jam_strings.cpp startup.cpp subst.cpp sysinfo.cpp timestamp.cpp variable.cpp w32_getreg.cpp modules/order.cpp modules/path.cpp modules/property-set.cpp modules/regex.cpp modules/sequence.cpp modules/set.cpp /link kernel32.lib advapi32.lib user32.lib Das System kann den angegebenen Pfad nicht finden. It tries to start "C:/Program Files (x86)/Microsoft Visual Studio/2019/Enterprise/VC/Tools/MSVC/14.27.29110/bin/Hostx64/x64/cl.exe". Unfortunately at my system, I don't have this path. I have C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise\VC\Tools\MSVC\14.28.29910... Please note the different number after "MSVC" What is the problem? How can I fix this? TIA and best regards Andreas -- ("`-''-/").___..--''"`-._ `o_ o ) `-. ( ).`-.__.`) (_Y_.)' ._ ) `._ `. ``-..-' _..`--'_..-_/ /--'_.' .' (il).-'' (li).' ((!.-' Andreas Tscharner andy(a)stupidmail.ch ICQ-No. 14356454

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Persistent CI failures for old compilers
by Jeff Garland 02 May '21

02 May '21

On at least the clang 3.8 and gcc4.8 I'm seeing python errors block the CI from running correctly. Downloading/unpacking pip==20.3.4 Cannot fetch index base URL https://pypi.python.org/simple/ Could not find any downloads that satisfy the requirement pip==20.3.4 Which of course has nothing to do with the compiler. Here's an active change where the CI is running. https://github.com/boostorg/date_time/pull/192 So the question is -- are these two old and now unsupported? Is there some CI setup change I need? I'd like to stop having to override the CI obviously. Thanks, Jeff

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Re: [boost] C++Now 2021 -- Library in a Week: Boosting Boost
by Bjorn Reese 02 May '21

02 May '21

On 2021-05-01 00:55, Jeff Garland via Boost wrote: > Every year at the end of the session, I solicit ideas from the community > about what 'library' we should work on in the following year. One Boost.Tokenizer could do with a modernization. It generates a lot of code for even simple tokenizations, which makes it unsuitable for embedded devices. Some issues to consider: * Separate the browsing API from the conversion API. ** The browsing API should use string_view. ** The conversion API should use output buffers instead of returing a string. * Provide an API with narrow contracts * Provide a constexpr API.

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C++Now 2021 -- Library in a Week: Boosting Boost
by Jeff Garland 01 May '21

01 May '21

C++Now 2021 is next week. For those that have never been, every year we have a workshop session called Library in a Week. While the goal of the session might be obvious from the title, needless to say, final Boost libraries don't happen in a week. So, actually, the real underlying goal is to build boost community and discuss c++ library design with projects that don't conflict with attendees day jobs. Every year at the end of the session, I solicit ideas from the community about what 'library' we should work on in the following year. One consistent suggestion has been to work on boost community maintenance. With the conference all virtual this year, I think this is the year to do it. The goal will be to generate pull requests from new or even old boost participants to improve our code base. While I'm sure we could wander around the various libraries and find issues that need some work to generate pull requests, I'm posting this looking for suggestions from the bigger community. Note that this doesn't need to be exclusive to new code -- it can be documentation or tests. Are there particular libraries we should look at? Are there particular issues that someone would like a hand tackling? Are there some upgrades to newer c++ features that someone could jump in on? Thanks, Jeff

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Boost N-Dimensional Array Library
by pencilcaseman＠gmail.com 28 Apr '21

28 Apr '21

Hi All, Would there be any interest in an n-dimensional array library for boost? There is Boost.MultiArray library, but as far as I can tell, this only supports containing the arrays, not performing arithmetic on them. It would provide an interface similar to what Numpy provides, would be fully templated and might, if possible, support BLAS routines to accelerate the functions. Thanks, Toby

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[ci][security] Codecov security breach
by Andrey Semashev 27 Apr '21

27 Apr '21

Hi, I found this in my news feed today: The codecov-bash script that is used to upload codecov reports from CI to codecov.io was maliciously modified to collect sensitive information and send to a third party server. Things like private keys, credentials, auth tokens used in the CI might be compromised. https://discuss.hashicorp.com/t/hcsec-2021-12-codecov-security-event-and-ha… https://about.codecov.io/security-update/ I'm not using codecov, and I have vague understanding how it works, but I've seen it used in Boost libraries' CI. I don't know if they are affected, this is an FYI to the maintainers.

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Fwd: [BOOST][GIL][Histogram]Ordered Maps in place of unordered maps
by sayan chaudhuri 26 Apr '21

26 Apr '21

---------- Forwarded message --------- From: sayan chaudhuri <sayanchaudhuri758(a)gmail.com> Date: Sat, Apr 24, 2021 at 3:08 PM Subject: [BOOST][GIL][Histogram]Ordered Maps in place of unordered maps To: <boost-gil(a)lists.boost.org> Dear Matseuz, The histogram implemented in boost gil uses an unordered map.Wont it have been better with an ordered map? Because the worst case time complexity is better in case of ordered maps. Regards, Yours sincerely, Sayan Chaudhuri

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[Boost][Multiarray]Move for_each.hpp from examples to boost/multi_array
by sayan chaudhuri 25 Apr '21

25 Apr '21

Hello Everyone, I wish to draw attention to the fact that the for_each header file for multiarrays in boost is not present in the include/boost section of the boost multiarray repository. Also, the header file does not have a namespace defined inside it and so the compiler becomes confused as to which for_each function to follow, the one from stl or this one. The for_each is a great utility for boost multiarrays reducing code size and increasing readability. I would like to what others would like to say about these changes. Making these changes allows contributors to other boost libraries to use that functionality in a proper manner. Thanking everyone, Yours sincerely, Sayan Chaudhuri

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[iostreams] [build] Why do iostream tests link against static libraries ?
by Brian Kuhl 22 Apr '21

22 Apr '21

Cross-posting since boost-build is quiet these days. I’m trying to get iostreams working with shared libraries on VxWorks The tests will compile with clang 11 if I comment out the forced dependency on static libraries But I’d like to understand the reason for forcing a link of static libraries with a dynamic executable? https://github.com/boostorg/iostreams/blob/4d2e763ba8b88f3350fbea29b54507a3… rule test-iostreams ( sources * : requirements * : target-name ? ) { return [ run $(sources) /boost/test//boost_unit_test_framework # /<link>static /boost/filesystem//boost_filesystem # /<link>static : # command : # input files : # build requirements <toolset>msvc:<define>_CRT_SECURE_NO_DEPRECATE <toolset>msvc:<define>_SCL_SECURE_NO_DEPRECATE <toolset>cw-9.3,<os>darwin:<runtime-link>static <define>BOOST_IOSTREAMS_NO_LIB <link>shared:<define>BOOST_IOSTREAMS_DYN_LINK=1 $(requirements) : $(target-name) ] ; } If I don’t comment, I get a link error. VxWorks only supports -fpic vs -fPIC clang-vxworks.compile.c++ ../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/unit_test_parameters.o "wr-c++" -x c++ -Wno-c99-extensions -Wno-variadic-macros -O3 -finline-functions -Wno-inline -Wall -pedantic -g -Wno-inline -DBOOST_ALL_NO_LIB=1 -DBOOST_BEAST_ALLOW_DEPRECATED -DBOOST_BEAST_SEPARATE_COMPILATION -I".." -c -o "../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/unit_test_parameters.o" "../libs/test/src/unit_test_parameters.cpp" clang-vxworks.archive ../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/libboost_unit_test_framework.a "wr-ar" rcu "../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/libboost_unit_test_framework.a" "../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/compiler_log_formatter.o" "../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/debug.o" "../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/decorator.o" "../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/execution_monitor.o" "../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/framework.o" "../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/plain_report_formatter.o" "../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/progress_monitor.o" "../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/results_collector.o" "../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/results_reporter.o" "../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/test_framework_init_observer.o" "../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/test_tools.o" "../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/test_tree.o" "../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/unit_test_log.o" "../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/unit_test_main.o" "../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/unit_test_monitor.o" "../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/unit_test_parameters.o" "../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/junit_log_formatter.o" "../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/xml_log_formatter.o" "../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/xml_report_formatter.o" clang-vxworks.link ../bin.v2/libs/iostreams/test/array_test.test/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/array_test.vxe "wr-c++" -o "../bin.v2/libs/iostreams/test/array_test.test/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/array_test.vxe" "../bin.v2/libs/iostreams/test/array_test.test/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/array_test.o" "../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/libboost_unit_test_framework.a" "../bin.v2/libs/filesystem/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/libboost_filesystem.a" -shared --start-group --end-group -fpic /opt/git/vx7/compilers/llvm-11.0.0.1/LINUX64/bin/ldarm: ../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/libboost_unit_test_framework.a(test_tools.o): relocation R_ARM_MOVW_ABS_NC against `a local symbol' can not be used when making a shared object; recompile with -fPIC /opt/git/vx7/compilers/llvm-11.0.0.1/LINUX64/bin/ldarm: ../bin.v2/libs/test/build/clang-vxworks-11.0.0.1/debug/cross-compile-vxworks/link-static/libboost_unit_test_framework.a(test_tree.o): relocation R_ARM_MOVW_ABS_NC against `a local symbol' can not be used when making a shared object; recompile with -fPIC

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Reminder: BinTray is shutting down 1-May
by Marshall Clow 21 Apr '21

21 Apr '21

Bintray is “sunsetting” on the 1st of May. At that time, you will be unable to download boost releases from there. Before that time, their service will be occasionally interrupted. We will be updating the web site before then, but the new location is: https://boostorg.jfrog.io/artifactory/main/release/ <https://boostorg.jfrog.io/artifactory/main/release/> So instead of downloading from: https://dl.bintray.com/boostorg/release/1.76.0/source/boost_1_76_0.tar.gz You should download from: https://boostorg.jfrog.io/artifactory/main/release/1.76.0/source/boost_1_76… This applies to all releases from 1.63.0 onward — Marshall

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Master branch now open for merging
by Marshall Clow 19 Apr '21

19 Apr '21

No restrictions; the release calendar is up to date. https://boost.org/development <https://boost.org/development> Next milestone: 23-Jun Boost 1.77.0 closed for new libraries and breaking changes — Marshall

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Re: [boost] [Boost-users] [release] Boost 1.76.0
by Glen Fernandes 17 Apr '21

17 Apr '21

On Fri, Apr 16, 2021 at 7:28 PM Edward Diener wrote: > I noticed on the main web page where it has under > "News" the "Version 1.76.0" that "Updated Libraries:" list nothing even > though there are plenty of updates for libraries at > https://www.boost.org/users/history/version_1_76_0.html. The fix for this has been committed; it should take effect automatically in about an hour or so. Glen

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[release] Boost 1.76.0
by Marshall Clow 16 Apr '21

16 Apr '21

Release 1.76.0 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 no new libraries and numerous enhancements and bug fixes for existing libraries. For details, including download links, see <http://www.boost.org/users/news/version_1.76.0> You can also download directly from: <https://boostorg.jfrog.io/artifactory/main/release/1.76.0/> To install this release on your system, see <http://www.boost.org/doc/libs/release/more/getting_started/index.html> Thanks to everyone who participated in this release. Thanks, -- The Boost Release Team Marshall Clow, Michael Caisse, Glen Fernandes

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[release] Boost 1.76.0 Release Candidate 12
by Marshall Clow 14 Apr '21

14 Apr '21

The second release candidates for the 1.76.0 release are now available at: <https://boostorg.jfrog.io/artifactory/main/release/1.76.0/source/ <https://dl.bintray.com/boostorg/release/1.76.0/source/>> The SHA256 checksums are as follows: 7bd7ddceec1a1dfdcbdb3e609b60d01739c38390a5f956385a12f3122049f0ca boost_1_76_0_rc2.tar.gz 0fd43bb53580ca54afc7221683dfe8c6e3855b351cd6dce53b1a24a7d7fbeedd boost_1_76_0_rc2.zip 88782714f8701b6965f3fce087a66a1262601dd5ccd5b2e5305021beb53042a1 boost_1_76_0_rc2.7z f0397ba6e982c4450f27bf32a2a83292aba035b827a5623a14636ea583318c41 boost_1_76_0_rc2.tar.bz2 Changes from RC1: * A missing include was added to a Boost.Regex header. This fixes compilation on gcc 11. As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. -- The Release managers

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[gsoc21][boost.multiprecision] Realisation of Quad Double
by Abhishek Kujur 13 Apr '21

13 Apr '21

Greetings, My name is Abhishek Kujur, I am CSE student at Kalinga Institute of Technology. I have used c++ for like 6 years and I have understanding of C++ Stl, object orientation and template metaprogramming. I would love to be selected at GSOC 2021 by contributing to C++'s well known library, Boost Library. I would be interested in feedback and suggestions. The link to my proposal is: https://docs.google.com/document/d/1NnrBhA4Hu0JYwjSSQJgCTlgYZaYl2FrVinp6h-Z…

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Unable to utilize Boost C++ libraries in VS Code 2021.
by Sidhaant Gupta 13 Apr '21

13 Apr '21

I added the boost root directory to my workspace, it didn't work. I have also installed the boost using bootstrap.bat but it still doesn't work.

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[gsoc2021]Proposal: Image Processing Algorithms
by ansh grover 13 Apr '21

13 Apr '21

------------------------------ Hi, I am Ansh Grover, a GSoC applicant. I am interested in contributing to the Boost C++ library on the project "*Generic Image Library. I have been coding in C++ for over 6 months, with no prior experience working with Boost libraries. But I am interested in start working with boost libraries and I am willing to put effort into this project by proposing to work for over 30+ hours per week. I have read the problem statement and under GIL there's a project 2 about implementing image processing algorithms and in that list, I would like to work on implementing the k-means clustering algorithm. It would be very helpful if you can guide me through this project. Honestly, I don't expect to be selected for the project with my experience as I am aware of how much work and experience is required, I am just applying with a positive attitude. I am open to any suggestions and I shall proceed with the task upon your acknowledgment. Regards, Ansh Grover

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I will be uploading my GSoC 2021 proposal today
by Sidhaant Gupta 13 Apr '21

13 Apr '21

I have been working on my proposal for a week now, but didn't draft it for review yet as I was making it on MS Word and wasn't aware of the review feature on the official GSoC application portal. Kindly pardon me if it falls short of your expectations but rest assured that I will be in touch with all of you from now on. So please do not end the judgement on the proposal and give me a chance to prove my mettle in the coming month before finalising the selections. Kind regards, Sidhaant Gupta

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[gsoc21] - Provide quad-double precision for Boost.Multiprecision
by Γιάννης Γονιδέλης 13 Apr '21

13 Apr '21

Hello, My name is Giannis Gonidelis. I am an Electrical & Computer Engineering student from Greece and a regular open-source contributor on HPX developed by STE||AR Group. The past year I have been working on trying to adapt the HPX Parallel Algorithms to C++20 by providing the interface dictated by Ranges-TS (by Niebler). HPX, being a C++ Standards library for Concurrency and Parallelization, has its roots on Boost and widely adopts template meta-programming (our project leader is also the founder of Boost.Spirit). I recognize that I might kick in a little late for a GSoC application, but before sharing my proposal, I would like to know if you plan on mentoring the project about providing the "Quad-Double Backend Type". If so, I would be glad to share my initial thoughts on the project with the mentor, along with my Programming competency test script, in order to submit a cohesive and thorough proposal. Please inform me on the project availability. Regards, Giannis Gonidelis GitHub: gonidelis<https://github.com/gonidelis>

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select_stdlib_config.hpp including <version> vs <VERSION> on OS X
by Allen Sanderson 12 Apr '21

12 Apr '21

Hello, A casual boost user and abuser here. Some specifics on my OS OS X Big Sur 11.2 Xcode 12.4 Compiler clang : Apple land version 12.0.0 Boost 1.73 - forward When select_stdlib_config.hpp is included it gets to this initial code to include <version> ... #if defined(__cplusplus) && defined(__has_include) # if __has_include(<version>) // It should be safe to include `<version>` when it is present without checking // the actual C++ language version as it consists solely of macro definitions. // [version.syn] p1: The header <version> supplies implementation-dependent // information about the C++ standard library (e.g., version number and release date). # include <version> ... The issue is that many projects (gnuplot, builtbot, and others) have a VERSION file in their top level src directory. On a traditional Linux system the case sensitivity would make sure the right file is included. However, many/most OS X file systems are case insensitive. As such, the project's VERSION file gets included instead. And does not compile. I have no solution to the issue other than I renamed our project’s VERSION file for the time being. However, I wanted to raise the issue as I noticed it when moving to 1.75 and backtracked out that it was a recent changed starting with boost 1.73 Cheers, Allen Sanderson SCI Institute University of Utah

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A new home for Boost releases
by Marshall Clow 12 Apr '21

12 Apr '21

We’ve been using BinTray to host our releases for a few years, and it’s worked well for us However, JFrog is shutting down BinTray soon (at the end of this month). We have moved all the releases that were hosted on BinTray over to JFrog Artifactory. They are at https://boostorg.jfrog.io/artifactory/main/release <https://boostorg.jfrog.io/artifactory/main/release> For example, instead of: https://dl.bintray.com/boostorg/release/1.74.0/source/boost_1_74_0.tar.gz <https://dl.bintray.com/boostorg/release/1.74.0/source/boost_1_74_0.tar.gz> You should now use: https://boostorg.jfrog.io/artifactory/main/release/1.74.0/source/boost_1_74… <https://boostorg.jfrog.io/artifactory/main/release/1.74.0/source/boost_1_74…> I’ll be updating the web site soon, but if you have automation that relies on BinTray, you should update it to use the new home. — Marshall P.S. The “nightly” snapshots will live there too, as soon as we get that set up.

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[GSoC][GSoC21] Proposal for new quad-double type in Boost.Multiprecision
by Fahad Syed 12 Apr '21

12 Apr '21

Greetings, My name is Syed Fahad, and I am a Electrical Engineering undergraduate student at National Institute of Technology, Srinagar. I have outlined a proposal for implementation of a new quad-double type based on David Bailey’s QD package. So the plan outline is to initially implement quad-double and double-double types as a wrapper around the QD packages qd_real and dd_real classes, and write the testing and benchmarking routines. Eventually, write a generic multiple-double class from scratch using the same algorithms as QD, and remove dependency on external libraries wherever possible. I would be very interested in feedback, questions, and comments. I am looking for supervisors/mentors to undertake this project as part of GSoC 2021. Apologies for the apparently late proposal submission. The link to my proposal is: https://docs.google.com/document/d/10_y6bMk8YkBXXZk5iZr4zJafBwsmJI910Tl K8mDYa80/edit?usp=sharing Best, Syed Fahad.

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Multiprecision
by shady mohamed 12 Apr '21

12 Apr '21

I need to understand the competency test of multiprecision project

2 1

boost root include folder
by Alexander Grund 12 Apr '21

12 Apr '21

Hi all, I wanted to propose moving the top-level include folder "boost" (basically a symlink to all libs/*/include/boost headers) into a subfolder "include" and add (only) that to `-I` by the root Jamfile. See https://github.com/boostorg/boost/issues/501 In short: The current practice of adding the project root folder to the include paths leads to compilers picking up non-header files, like <version>, which has led to trouble in other projects already. (Not a problem with Boost yet AFAIK, so this is a general observation) Boost should be a good example, and NOT do that too. There might be some fallout outside of Boost for users not using an installed or staged Boost version but rely on the root boost folder, but the fix is trivial and IMO well reasoned. And e.g. CMake (very likely) would already handle that change just fine without modifications. Regards, Alex

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Re: [boost] Vector with compile-time polymorphism
by Ivica B 11 Apr '21

11 Apr '21

Yes, I guess it is very similar (if not the same) to polly_collection, or more specifically to: boost::any_collection. Is there a data structure that is similar to polly_collection but can be sorted? On Fri, Apr 9, 2021 at 2:47 PM Ivica B via Boost <boost(a)lists.boost.org> wrote: > multivector<rectangle, circle, triangle> mvect; > Each type is held in a separate std::vector for that type. So in the above > case, multivector<rectangle, circle, triangle> consists of three > std::vectors: std::vector<rectangle>, std::vector<circle> and > std::vector<triangle>. > Sounds a bit like https://www.boost.org/doc/libs/1_75_0/doc/html/poly_collection.html no? --DD

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[GSOC2021][Boost.uBLAS][Draft Proposal]Create new matrix and vector types
by Mr. Cell 11 Apr '21

11 Apr '21

Create new matrix and vector types This is with reference to the communication and as advised by my mentor (Mr. Amit Singh). I am hereby attaching my draft project proposal for boost::uBlas for review and suggestions if any. https://docs.google.com/document/d/1SXB9r_3dbgD0kT5xNmFzQ5mD0FuvTO0Y5TOkdyr… Thanks & Regards.

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[release] Boost 1.76.0 Release Candidate 1
by Marshall Clow 11 Apr '21

11 Apr '21

IMPORTANT NOTE: This will be the last RC posted on BinTray! The first release candidates for the 1.76.0 release are now available at: <https://dl.bintray.com/boostorg/release/1.76.0/source/> The SHA256 checksums are as follows: aaf920e31ae815ff6b55d70a28bb614a6aa6f5cd2f6e4543461d20a4fe39df4e boost_1_76_0_rc1.7z 5dd0c91e1f0f18d452fcaa772d9c30815e449dd4fe99fadf224cca180d98cee3 boost_1_76_0_rc1.zip 5b9844335bc327272030b8050cf417178d26c8abbc64ed7aefc4d818facc1c10 boost_1_76_0_rc1.tar.gz cea1cf7609daf5bb285a625530e8d660dca51816007da7f5eb3f577b685a888d boost_1_76_0_rc1.tar.bz2 As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. -- The Release managers

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The descriptor does not fit into the select call's fd_set
by George Nistor 10 Apr '21

10 Apr '21

Hi all, I am having a problem with the following error message '' The descriptor does not fit into the select call's fd_set" The setup I have is QNX , VSomeIP lib (socket abstractisation lib) , lib Boost 1.61 (a very old version) I get the error in this lib VSomeIp from the bellow boost call. The call to boost::asio::async_write(3 params) gives the above error message. I have tried to see also on QNX with > pidin -p vsomeip fds How many open file descriptor do I have and I got value 123. As far as I know there is a limitation 1024 of open file descriptors. Could you provide some help? Does the latest boost lib solve this particular case? I appreciate any suggestion, Also please say if any info is missing Thanks George Nistor

2 1

Vector with compile-time polymorphism
by Ivica B 09 Apr '21

09 Apr '21

Hi! I am doing a performance C++ work and there is a data structure that we use and I think it is very useful even for the general public. Here is the description: Currently, I call it *multivector* (I know there is a data structure with the same name, this is a temporary name). It works like this: You specify all the types you want to hold in your multivector: multivector<rectangle, circle, triangle> mvect; Each type is held in a separate std::vector for that type. So in the above case, multivector<rectangle, circle, triangle> consists of three std::vectors: std::vector<rectangle>, std::vector<circle> and std::vector<triangle>. Now, the magic happens when we use templates to process all three vectors at once. Imagine there is a function *draw* for all three types. We can do something like this: mvect.for_each([&](auto& shape) { shape.draw(bitmap); }); The above code generates three for_each loops, for rectangle, circle and triangle. Inside the loops it calls the draw method for each type. There is no dispatching inside the loops, and the loops are really easy for the compiler to optimize (due to their simplicity). Prototype implementation: https://github.com/ibogosavljevic/johnysswlab/blob/master/2021-02-virtualfu… Advantages over std::vector<std::variant>>: * Uses less memory (std::variant uses the amount of memory per element that is big enough to store the biggest type) * Is more optimal: each type generates its own processing loop, there is no dispatching code inside the loop. The compilers vectorized these loops easier. Downsides: * You cannot sort the elements in the whole vectors (even though you can sort them in individual containers) * Code bloat (many types can create a lot of code, this is the case with std::vector<std::variant>> too) Please let me know what you think. Ivica

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GSoC proposal review
by Aditya Tiwari 09 Apr '21

09 Apr '21

Hello all, I'm Aditya Tiwari, a GSoC aspirant. I've submitted my proposal for Boost GIL (generic image library) on GSoC's website under boost. I would be grateful if someone review's my proposal and give me suggestions if needed. I've shared the doc link of my proposal with commenter rights. Thanks and Regards, Aditya Tiwari

1 0

Request to review my proposal
by Pratik Awasthi 08 Apr '21

08 Apr '21

Hello Mentor, I Pratik Awasthi request you to review my GSOC 2021 proposal and do suggest updates https://docs.google.com/document/d/1eeuXx4x2birJXxQChEUnBrLbWTzKd8oc9UspeYU…

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[GSoC'21]Seeking Review of draft Proposal for Project 3: Finalize DataFrame Implementation
by Kowndinya Renduchintala 08 Apr '21

08 Apr '21

Hello everyone! I am Kowndinya Renduchintala, a second Year Undergrad in Computer Science and Engineering Department at Indian Institute of Technology Bombay(IIT Bombay). TO THE COMMUNITY: In short, this project’s end goal is to add to the dataframe implementation of GSoC’19, inspired from R, Python and others. This already has features like constructing a column of data frame, the data frame itself in a couple of ways and also supports operations like select, join etc. My main focus is on adding features that are most desired by a data scientist working with REAL WORLD data and I have added some such possible features in the draft linked below. I have never been into Open Source Software Development before. I would like to make this first attempt of mine a success and I hence seek for advice from anyone willing to spare time, to improve upon my list of deliverables, for establishing the foundation of Boost.uBlas as a new data science library. TO THE MENTOR(David): My progress so far: I have glanced through the GSoC’19 implementation, and referred to some pandas docs to make this draft. I am actually a bit worried because I was too late at completing my Competency test and contacting you, the main reason being a very hectic coursework of mine. The only remaining things are – Modifying the README.md for GitHub Actions Usage and some basic error handling in the code. I have shared the draft in the Google’s portal which also contains a link to my forked repository of ublas, containing my solutions to the competency test. I will also be completing the remaining things(possibly also improve small parts like updating naïve matrix multiplication to Strassen’s) in about 2 days. Also, I want to have a little chat with you as I found out that you were the mentor for this project in 2019 and you might be having some pre-conceived ideas on improving the current implementation, from your previous interaction. Please let me know what you think… Here is the link to my proposal draft : https://drive.google.com/file/d/1cnSrrOWfbteJKlmGxiIY9R5H_-YSkb-n/view? usp=sharing Cheers, Kowndinya

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regarding submission of my first proposal
by amit kumar 08 Apr '21

08 Apr '21

Hello i am Amit kumar. I am currently in third year of undergraduate bachelor's degree program , my field of study is Information Technology.I really curious about open source development and i always support open source software , but i have never contributed to any open source project . I have intermediate level command on c++ and i am doing competitive programming from my first year two and half year from now this is my codeforces <https://codeforces.com/profile/stream_cipher> and codechef <https://www.codechef.com/users/ammitkumar> profile link. I am very beginner to the field of software development but i know some website development . I really want to contribute to the Boost C++ library but i don't have any idea about how to submit the first proposal and how to select the topic on which i should work on please suggest me the path way. waiting for your reply. Thaks :)

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[Boost] [Lambda2] Review starts Monday March 22, 2021 to March 31, 2021
by Joel de Guzman 08 Apr '21

08 Apr '21

The Boost formal review of the Lambda2, authored by Peter Dimov, starts Monday, March 22, 2021 to March 31, 2021 (inclusive). Documentation: https://pdimov.github.io/lambda2/doc/html/lambda2.html Source: https://github.com/pdimov/lambda2/ Lambda2 is a simple, but functional, C++14 lambda library. It takes advantage of the fact that the standard <functional> header already provides placeholders _1, _2, _3, and so on, for use with std::bind, and function objects such as std::plus, std::greater, std::logical_not, and std::bit_xor, corresponding to arithmetic, relational, logical and bitwise operators. Please provide in your review information you think is valuable to understand your choice to ACCEPT or REJECT including Lambda2 as a Boost library. Please be explicit about your decision (ACCEPT or REJECT). Some other questions you might want to consider answering: - What is your evaluation of the design? - What is your evaluation of the implementation? - What is your evaluation of the documentation? - What is your evaluation of the potential usefulness of the library? - Did you try to use the library? With which compiler(s)? Did you have any problems? - How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? - Are you knowledgeable about the problem domain? More information about the Boost Formal Review Process can be found at: http://www.boost.org/community/reviews.html The review is open to anyone who is prepared to put in the work of evaluating and reviewing the library. Prior experience in contributing to Boost reviews is not a requirement. Thank you for your efforts in the Boost community. They are very much appreciated. Peter is often available in the CppLang Slack #boost channel should you require any clarification not covered by the documentation. I am not frequently available in the Slack channel, but I'll certainly pay attention to the discussions. Please don't hesitate to ping me if needed. Cheers, --Joel de Guzman

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FFT proposal for gsoc 2021
by Eduardo Quintana 08 Apr '21

08 Apr '21

Hi Boost community, I've been working on a C++ templated library for Fast Fourier Transforms, https://github.com/Lagrang3/fftx. Templated because some FFT algorithms are algebraic-field independent, eg. you could FFT an array of N matrices provided a Nth matrix-root-of-unity is given. As a result you could have a single algorithm for a variety of underlying, eg. `std::complex<float>`, `std::complex<double>`, `std::complex<long double>`, `boost::math::quaternion`, finite field types (this would yield the "Number theoretic transform" https://cp-algorithms.com/algebra/fft.html#toc-tgt-6) I would like to improve this library during the GSOC 2021, as a proposal for inclusion inside Boost.Math or Boost.Algorithms. Is there anyone interested in supervising this project? Any opinions? Best regards, Eduardo Quintana

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[GSoC 2021] Proposal for Boost.xml
by qiqi tang 07 Apr '21

07 Apr '21

Hello, My name is Fuqi Tang who is a graduate student in China. I am majoring in Software engineering. I want to take part in GSoC 2021 for the Boost.xml project and I will really appreciate it if the community can watch my proposal and give me some advice to improve it. Below is my proposal link https://docs.google.com/document/d/1GYuiVqU8ChaTG2RO2qhQbpF9QSuK5uGRRNDx0M2… Thanks a lot! Regards, Fuqi

2 1

Review and Feedback for Boost.XML proposal
by YAGNIK VAGHELA 07 Apr '21

07 Apr '21

Hello, I am Yagnik Vaghela. I live in India. I am a 3rd year undergraduate student pursuing B.tech in ICT(Information and communication Technology) at DA-IICT. I would like to participate in GSoC this year. I would like to work on a project Boost.XML library. Here's my draft proposal. Please kindly review it and give feedback. any suggestions would be appreciated. https://docs.google.com/document/d/14rzb_3W_5lNM5_qfYpV4zVOh3QmOwuQgWLfeem_…

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[GSoC] Boost.Real GSoC Proposal Feedback
by Divyam Singal 07 Apr '21

07 Apr '21

Hi all, This is Divyam, a 2nd year CSE student at IIT Guwahati. I have shared my draft proposal through GSoC website. I have shared the drive link to the pdf, as docs don't support rendering of LaTeX maths and graphs. You can comment to provide review by right-clicking that portion in the pdf. Do have a look at it and provide the feedback so that I can make the necessary changes. Thanks and Regards, Divyam Singal

1 0

boost mailing list archive stopped updating
by Janek Kozicki 07 Apr '21

07 Apr '21

Just a heads-up, boost mailing list archive stopped updating 3 days ago: https://lists.boost.org/Archives/boost/ best regards Janek -- Janek Kozicki, PhD. DSc. Arch. Assoc. Prof. Gdańsk University of Technology Faculty of Applied Physics and Mathematics Department of Theoretical Physics and Quantum Information -- http://yade-dem.org/ http://pg.edu.pl/jkozicki (click English flag on top right)

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[Boost][GIL][GSOC21]Review and Feedback for Boost GIL project proposal
by sayan chaudhuri 07 Apr '21

07 Apr '21

Hello Everyone, My name is Sayan Chaudhuri. I am a final year,undergraduate student,in the Computer Science and Engineering department of IEM,India . I am eager to participate in the GSOC 2021 and willing to contribute to the Boost GIL library. I am looking to implement the ORB feature descriptor for BOOST GIL . Currently the only keypoint detector present is Harris Corner. And no separate descriptors are present. ORB comes with both a keypoint detector and descriptor bundled and it is suitable for real time systems and also license free. Feature descriptors are important for tasks like object recognition, structure from motion, image stitching etc. And ORB is a good choice for real time systems. I am attaching the link of my project proposal for the same below. I would request anyone who is interested to mentor me or co-mentor to kindly have a look at my proposal. I would really appreciate any feedback from your side and I am looking to continue the discussion of the project further. Proposal link : https://docs.google.com/document/d/1ARL57qRdNWPGe3GlqY1n8E31LyUCvyIyvBk_agz… Thank you.

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[release] 1.76.0 post-beta merges
by Marshall Clow 06 Apr '21

06 Apr '21

The master branch is is now open for post-beta merges, but only as described in the Post-Beta Merge Policy. See <https://github.com/boostorg/boost/wiki/Releases%3A-Beta-Merge-Policy> Reminder: The master branch closes for the release on Wednesday, Apr 7. Full calendar here: https://www.boost.org/development/ <https://www.boost.org/development/> — Marshall P.S Doc changes and test changes do NOT require release manager approval to be merged.

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[gsoc21] Feedback and advice on proposal
by Haoran Xu 04 Apr '21

04 Apr '21

Hi, I'm really interested in applying for GSoC 2021 and implementing the Boost.XML library. I have completed the competency test and have drafted by proposal. https://docs.google.com/document/d/1KP-g1zMXQdqUzSFMtsURcSpZisjjspvX8lRkdRj… Please tell me what you think this proposal is missing and what I should add on. It's my first time applying for GSoC so I'm not very familiar with the process. Thank you!

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Re: [boost] [Boost][GIL][GSOC21] Draft Proposal for Boost GIL
by sayan chaudhuri 04 Apr '21

04 Apr '21

Hello Everyone, My name is Sayan Chaudhuri. I am a final year,undergraduate student,in the Computer Science and Engineering department of IEM,India . I am eager to participate in the GSOC 2021 and willing to contribute to the Boost GIL library. I am looking to implement the ORB feature descriptor for BOOST GIL . Currently the only keypoint detector present is Harris Corner. And no separate descriptors are present. ORB comes with both a keypoint detector and descriptor bundled and it is suitable for real time systems and also license free. Feature descriptors are important for tasks like object recognition, structure from motion, image stitching etc. And ORB is a good choice for real time systems. I am attaching the link of my project proposal for the same below. I would request anyone who is interested to mentor me or co-mentor to kindly have a look at my proposal. I would really appreciate any feedback from your side and I am looking to continue the discussion of the project further. Proposal link : https://docs.google.com/document/d/1ARL57qRdNWPGe3GlqY1n8E31LyUCvyIyvBk_agz… . Thank you.

1 0

Re: [boost] FFT proposal for gsoc 2021
by Eduardo Quintana 03 Apr '21

03 Apr '21

Hi Kostas, Good critics are necessary for the sake of improvement. All of your comments are welcome. > 1) The discussion of NTT. While boost.multiprecision can potentially be used > to implement the Zp ring, it currently does not contain any such construct. > Reading further, there is nothing about NTT in the deliverables. If the idea > is peripheral to the GSOC project, then it does not need to be mentioned at > all. Note that even the PARI library does not yet have NTT implemented and > for them I think it is a high priority (must be a very hard problem). 1) I mentioned the NTT because is part of the motivation for having a general DFT instead just complex-DFT. Maybe the text it is not clear. You'll get the NTT for free. See these two examples https://github.com/Lagrang3/fftx/blob/master/examples/ex02.cpp https://github.com/Lagrang3/fftx/blob/master/examples/ex03.cpp Unfortunately I haven't produced a convolution routine yet, hence in ex03 I had to compute it explicitely. There is also a small implementation of Zp https://github.com/Lagrang3/fftx/blob/master/examples/modulo.h if there was one in Boost I would gladly use it. > 2) Section 2.2. Most people know the Convolution Theorem, but at least myself > do not know anything about the Rader algorithm. Since you propose to > implement it, why not describe it in that Section, maybe instead of the > Convolution Theorem. 2) The Convolution Theorem is very well known yes. I wanted just to make a small subsection in order to clarify which flavour of the Convolution I am using: the Circular Discrete Convolution (CDC) which fits naturally into the DFT scheme. The other Discrete Convolution is the one that you write as c_i = \sum_{j} a_j b_{i-j} produces, in my opinion, many questions to the reader for instance: what do we do with the negative indexes? Zero-pad them or wrap around from the end? I think writing proofs and detailed algorithms is not necessary for the text of the proposal. Last year when I started the fftx experiment I came to the conclusion at some point that I needed, besides Cooley-Tukey and mixed-radix, another algorithm to compute the DFT for prime sizes. Then I found the description of Rader's algorithm in Wikipedia. FFTW uses it, by the way. > 3) Section 2.3. You say: "FFTW was designed to compute DFT for complex > numbers, like in Example 1. There is no support for DFT in the broader sense > of Definition 1. For example, we cannot use FFTW to compute the NTTs described > in the Example 2." Since you are not going to be able to solve this problem in > this GSOC project, it is better to not make such comments. 3) Yes I will solve that problem. There will be two back-ends: mine for general purposes DFTs and FFTW for complex DFTs. My back-end is half-way through I have implemented: - two versions of the mixed-radix Cooley-Tukes (aka Good-Thomas) recursively and not, - a pure Cooley-Tukey in-place which is the one in the blue line shown here: https://github.com/Lagrang3/fftx/blob/master/assets/powers-2.png That makes the back-end functional for any DFT size, with the inconvenience of the O(n^2) slow-down for prime numbers. The work to be done from now on will include the Rader algorithm (for the prime case) and further performance improvements. A funny thing about this general purpose DFT back-end is that I can test its performance against other complex-DFT (eg. FFTW). If some knows of a NTT library or the implementation of weirder DFTs to compare with, please raise your hand. > 4) Section 2.3. "scalability of the parallel MPI routines for computing > 3-dimensional DFT" , "domain decomposition" - here again I think it is worth > to remember that if the project is not going to address domain decomposition, > then it is better to not talk about it. 4) That's true. But that's a very urgent problem that we could very well solve originally within Boost. However it cannot be done until we produce a Boost FFT. Hence you get an extra motivation for doing the Boost FFT. > 5) Since this project is done under Boost, it seems logical to make sure the > proposed code work with Boost.Math complex types. Is this not part of the > plan? Why no word about it in the deliverables? 5) It did cross my mind, but I clearly forgot to talk about it. Thanks for alerting me. Thanks for the feedback. Eduardo

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[lambda2] Andrzej's review
by Andrzej Krzemienski 02 Apr '21

02 Apr '21

Hi Everyone, I recommend to REJECT Boost.Lambda2 library in its current form. My opinion is not very strong, and it is based on the perceived trade-off between usefulness and technical problems. I acknowledge that there are practical use cases that the library can address, that are not provided in documentation. (I recommend that examples with pointers, and maybe a complex one with column-oriented design be added). I consider the ADL issue that Barry pointed out a serious one. This will be an additional place where users would suddenly be caught by a magical problem that they will spend hours understanding. I think that the main problem here is that Boost.Lambda2 defines the operators that should belong to namespace std::placeholders. I also note that if this was added to the Standard Library, the problem would be nonexistent, because they would reside in namespace std. Could I propose an alternative design. Add placeholders _1, _2, ... into namespace `boost::lambda2::placeholders` specialize std::is_placeholder` for them, so that `std::bind` can recognize them. Add operators in the same namespace. Then, recommend the following usage of the library: ``` using namespace boost::lambda2::placeholders; void fun() { auto pred = std::bind(_1, &Employee::name) == std::bind(_2, &Employee::name); } ``` This single using directive would make both `std::bind` and Boost.Lambda2 operators work. I would find such a library acceptable. And in fact I could make it a condition for a conditional acceptance. Now, the standard questions: > - What is your evaluation of the design? > I object to the choice to add operators for placeholders from one namespace (std::placeholders) into another namespace (boost::lambda2). Save for that, I find anything else good. - What is your evaluation of the implementation? > Very sweet and clean. I only expect other operators to also work. But Peter already explained that this is his plan. - What is your evaluation of the documentation? > This library doesn't require much documentation of the interface. But I fill it is missing the Motivation section. I would expect to see practical examples: not long ones, but ones that I will find in real programs, like dealing with pointers. - What is your evaluation of the potential usefulness of the library? > Others have convinced me that it will find sufficient application in real programs. - Did you try to use the library? With which compiler(s)? Did you > have any problems? > I tried to reimplement it, and played with some toy examples in Wandbox. (newest GCC). It worked fine. - How much effort did you put into your evaluation? A glance? A quick > reading? In-depth study? > I was able to reimplement it, read the entire implementation (which was not difficult: it is like seventy lines). I spent like three hours in total studying it. - Are you knowledgeable about the problem domain? > I used Boost.Lambda and Boost.Bind in the past. Finally, I would like to thank Peter for writing and sharing this library. Regards, &rzej;

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Idea Suggestion for GsOC'21
by Sanyam Bhaskar 01 Apr '21

01 Apr '21

Hey! This is Sanyam Bhaskar. I read over the default Ideas provided to us and XML Parser really caught my eye. I would like to contribute to the same but don’t know where to start. Also, as per my understanding, XML is relatively outdated , when compared to data languages like JSON. So in addition to this being an XML Parser, I think adding a JSON parser alongside it would boost the library’s utility in the modern day industry. I Would appreciate it if someone could tell me how to get started and some feedback on the suggestion. Looking forward to contributing to the project. Yours, Sanyam Bhaskar

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[range] the strange behavior of adjacent_filter
by Andrzej Krzemienski 31 Mar '21

31 Mar '21

Hi everyone, Boost.Range has two GitHub issues on the strange behavior of adjacent_find that have been sitting there for more than two years: https://github.com/boostorg/range/issues/80 https://github.com/boostorg/range/issues/81 The behavior of the algorithm is not well described, but the intuitive expectation would be that it returns for every pair of adjacent elements that match the predicate the second of the pair. However, the unexpected behavior of the algorithm is that for a non-empty range it literally always returns the first element. I do not think that this is by accident, because Ranges V3 also expose the same behavior: https://godbolt.org/z/P33j1qvT6 Does anyone happen to know the reasoning or motivation behind this behavior? Regards, &rzej;

1 0

Interested in creating new matrix and vector types
by Gagandeep Bhatia 31 Mar '21

31 Mar '21

Hey, I'm Gagandeep Bhatia, currently pursuing the 2nd year in Christ University, Bangalore, India. You can reach me at gagandeepbhatia2303(a)gmail.com or +919466935025. I went through your upcoming projects on Google Summer of Code, your idea on creating new matrix and vector types is really impressive. The best part about your project is It supports all matrix sizes, from small fixed-size matrices to arbitrarily large dense matrices, and even sparse matrices. It supports all standard numeric types, including std::complex, integers, and is easily extensible to custom numeric types. It supports various matrix decompositions and geometry features I truly want to become part of this project for a better mutual achievement, in the past I have done a few projects, which will help me to contribute my best in this project. It will be really kind if you can share some more details about your project, so I learn more about your project. with regards.

2 2

Boost.Lambda2 usage
by Barry Revzin 31 Mar '21

31 Mar '21

Hey all, I spent this morning implementing views::zip using Boost.Lambda2 (because views::zip requires writing lots of single-operator lambdas, so it fits the problem quite well). You can see the implementation here: https://godbolt.org/z/jcjdd3xeo I ran into a few issues I wanted to point out. First, several operators are missing. This is the standard library's fault (it's weird that not even dereference is there). But if the standard library isn't going to provide them, I figure Boost.Lambda2 should, since these are probably going to come up so may as well just add a few more lines of code and call it a day. I needed to define five: * (unary), ++ and -- (prefix), +=, and -=. Second, this library has name lookup issues. Here's a reduced example ( https://godbolt.org/z/z8oEqnTnG) #include < https://raw.githubusercontent.com/pdimov/lambda2/develop/include/boost/lamb… > namespace N { struct Irrelevant { }; void operator+(Irrelevant, Irrelevant); int plus_one(int i) { using namespace boost::lambda2; return (_1 + 1)(i); } } This doesn't compile. _1 + 1 finds the appropriately-named irrelevant operator+ and stops there, and we never get to the operator+ in namespace boost::lambda2. Either the operators need to be put in namespace std::placeholders for ADL (which seems naughty, but also seems like something the standard library could potentially do?) or the library should provide its own placeholders. That would lose the nice _1 name, but gain the ability to provide both [] and (). Thanks for the library, Barry

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Re: [boost] [Boost][GIL][GSOC21]Wish to know about code review process
by sayan chaudhuri 30 Mar '21

30 Mar '21

Hello Everyone, I am a bit new to the world of open source and so I would like to know how the code review of pull requests is actually done. I have come to know that when I add a new feature to the library, I have to submit a test file along with my pull request. After that,what happens is unknown to me.Understanding this would help me to realize the entire process from pull requests to merging and therefore increase the quality of my contribution. I shall be highly thankful to anyone who may take time out of his/her busy schedule to explain this a bit to me. Thank you all.

2 1

gsoc21: Boost.Multiprecision: New Quad-Double Backend Type: Project 1: Implement a Feasible Realization of Quad-Double
by Orlando Nkengafac 29 Mar '21

29 Mar '21

Hello, My Name is Orlando. I am a nursing student at the Faculty of Health Sciences at the University of Buea, Cameroon. However, I have had in-depth private studies in C++. What is my next step for the test and submission of a proposal, for gsoc21: “Project 1: Implement a Feasible Realization of Quad-Double”. I would like to have a mentor? Sincerely, Orlando

1 0

gsoc21: Boost.uBlas: Matrix and Tensor Computations: Project 3: Finalize Dataframe Implementation
by Fatima Zifac 29 Mar '21

29 Mar '21

Hello, My name is Fatima. I study accounting in the University of Buea, Cameroon. However, I am very good in C++. I want to do the test and submit a proposal for gsoc21: “Project 3: Finalize Dataframe Implementation”. I would like to have a mentor? Sincerely, Fatima

1 0

gsoc21: Boost.uBlas: Matrix and Tensor Computations: Project 2: Create New Matrix and Vector Types
by Forcha Pearl 29 Mar '21

29 Mar '21

Hello, My name is Pearl. I am a student at the Faculty of Engineering, in University of Buea, Cameroon. I am enrolled for a Master’s Degree in Network Engineering and Security. I would like to do gsoc21: “Project 2: Create new matrix and vector types”. I would like to have a mentor? Regards, Pearl

1 0

gsoc21: Boost.uBlas: Matrix and Tensor Computations: Project 1: Finalize and Improve the Subtensor Type
by Glen forcha 29 Mar '21

29 Mar '21

Hello, I am Glen. I am doing my Phd in Software Engineering, at the University of Buea, Cameroon. I am interested in gsoc21: “Project 1: Finalize and Improve the Subtensor Type”. I would like to have a mentor? Regards, Glen

1 0

Re: [boost] [Boost][GIL][GSOC 2021] Contribute to the library
by sayan chaudhuri 28 Mar '21

28 Mar '21

Hello Everyone, I wish to convey my thanks to Matseuz Loskot and Pranam Lashkari, maintainers of Boost GIL for taking out time to go through my mail posting and also my pull request for KMeans Clustering. I have made the changes as suggested by Pranam Lashkari by replacing the .cpp file in example folder with .hpp file in the image_processing folder. I would request to kindly have a look at the submitted changes. Here is the link for the pull request : https://github.com/boostorg/gil/pull/587.. I shall soon be posting my project proposal in the mailing list.

1 0

[Boost][GIL][GSOC 2021] Contribute to the library
by sayan chaudhuri 28 Mar '21

28 Mar '21

Hello Everyone, My name is Sayan Chaudhuri. I am a final year,undergraduate student,in the Computer Science and Engineering department of IEM,India . I am eager to participate in the GSOC 2021 and willing to contribute to the Boost GIL library. I have already gone through the wiki list of Boost GIL listing the various image processing and computer vision algorithms that have not been implemented yet. I have also gone through the Contributing documents for BOOST GIL. . While going through the Boost Mailing List Archives, I found that Igor Antropov had suggested to develop ORB descriptor during his GSOC tenure but it has not been implemented yet.. I am therefore eager to develop the ORB descriptor for Boost GIL during GSOC 2021. ORB is useful in many situations like object recognition and structure for motion and also it is suitable for real time applications unlike SIFT and SURF. I also found out that while using Boost , everytime I need to see the output , I need to save the output in order to view it,thereby unnecessarily wasting memory when I do not wish to save the output. So, the functionality of imshow() for OPENCV is missing for Boost GIL. I am also eager to work on that functionality as well during GSOC 2021. Would therefore anyone is interested in mentoring me? As my programming competency test for Boost GIL, I have implemented the KMeans algorithm from scratch using Boost GIL and I have raised a pull request- https://github.com/boostorg/gil/pull/587. I would kindly request if someone can kindly review it. Also, I would like to know whether there are any similar issues that I can work on currently.

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Re: [boost] 14 to contact for introduction and guidance with gsoc mentor.
by Chandana Gubba 28 Mar '21

28 Mar '21

Sir/madam I does not have that great idea regarding Gsoc ,so firstly I want to know what about it exactly and how to apply and do project,and even about the eligibility ,I am ok with c++ programming. Is it enough ,these are my queries regarding gsoc. On Sun, 28 Mar, 2021, 7:20 pm , <boost-request(a)lists.boost.org> wrote: > Send Boost mailing list submissions to > boost(a)lists.boost.org > > To subscribe or unsubscribe via the World Wide Web, visit > https://lists.boost.org/mailman/listinfo.cgi/boost > or, via email, send a message with subject or body 'help' to > boost-request(a)lists.boost.org > > You can reach the person managing the list at > boost-owner(a)lists.boost.org > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of Boost digest..." > > > The boost archives may be found at: http://lists.boost.org/Archives/boost/ > > > Today's Topics: > > 1. Re: [Boost] [Lambda2] Review starts Monday March 22, 2021 to > March 31, 2021 (Peter Dimov) > 2. Re: [Lambda2] Review starts Monday March 22, 2021 to March > 31, 2021 (Peter Dimov) > 3. To contact project's mentor for GSoC21 (prince raj) > 4. Re: To contact project's mentor for GSoC21 > (Vin?cius dos Santos Oliveira) > 5. Re: To contact project's mentor for GSoC21 (Mateusz Loskot) > 6. Re: [Lambda2] Review starts Monday March 22, 2021 to March > 31, 2021 (Christian Mazakas) > 7. Re: [Boost] [Lambda2] Review starts Monday March 22, 2021 to > March 31, 2021 (Emil Dotchevski) > 8. Re: [Lambda2] Review starts Monday March 22, 2021 to March > 31, 2021 (Phil Endecott) > 9. Re: [Lambda2] Review starts Monday March 22, 2021 to March > 31, 2021 (Peter Dimov) > 10. [Boost][GIL][GSOC 2021] Contribute to the library > (sayan chaudhuri) > 11. (no subject) (Suraj Nehra) > 12. [GSoC] Boost.Real: Introduction and Guidence (Suraj Nehra) > 13. Changelog for 1.76 is outdated (Antony Polukhin) > 14. Re: Changelog for 1.76 is outdated (Antony Polukhin) > 15. Re: Boost Digest, Vol 6566, Issue 1 (shady mohamed) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Fri, 26 Mar 2021 14:10:43 +0200 > From: "Peter Dimov" <pdimov(a)gmail.com> > To: <boost(a)lists.boost.org> > Subject: Re: [boost] [Boost] [Lambda2] Review starts Monday March 22, > 2021 to March 31, 2021 > Message-ID: <144201d72239$0c182c30$24488490$(a)gmail.com> > Content-Type: text/plain; charset="utf-8" > > Mathias Gaunard wrote: > > It is not clear from the documentation what the capture behaviour of > > terminals is. > > I assume it's capturing rvalues by value and lvalues by reference? > > The capture behavior is inherited from std::bind, which captures > everything by value by default unless overridden with std::ref. > > > > ------------------------------ > > Message: 2 > Date: Fri, 26 Mar 2021 14:19:24 +0200 > From: "Peter Dimov" <pdimov(a)gmail.com> > To: <boost(a)lists.boost.org> > Subject: Re: [boost] [Lambda2] Review starts Monday March 22, 2021 to > March 31, 2021 > Message-ID: <144401d7223a$42e76ef0$c8b64cd0$(a)gmail.com> > Content-Type: text/plain; charset="utf-8" > > Andrzej Krzemienski wrote: > > Is it not just that the library is missing some operators? If > Boost.Lambda2 > > overloaded all overloadable operators there would be no point in users > doing > > it. > > I'll add the shift operators and the unary * at minimum, will see about any > others. The current set is determined by the function objects in > <functional>. > > > > ------------------------------ > > Message: 3 > Date: Fri, 26 Mar 2021 20:50:52 +0530 > From: prince raj <sdavil318(a)gmail.com> > To: "boost(a)lists.boost.org" <boost(a)lists.boost.org> > Subject: [boost] To contact project's mentor for GSoC21 > Message-ID: <B9EC3FCE-61E8-47E7-8665-FFFE6088824F(a)hxcore.ol> > Content-Type: text/plain; charset="utf-8" > > > > Hello, > > > My self Anish Kumar Singh and I want to participate to in boost > organisation. > > But I have no idea how to contact mentor for project discussion and my > ideas with him. > > So please help me contacting to mentor so that I can make my proposal > good to summit. > > > Thankyou... > > > ------------------------------ > > Message: 4 > Date: Fri, 26 Mar 2021 12:46:26 -0300 > From: Vin?cius dos Santos Oliveira <vini.ipsmaker(a)gmail.com> > To: Boost <boost(a)lists.boost.org> > Cc: prince raj <sdavil318(a)gmail.com> > Subject: Re: [boost] To contact project's mentor for GSoC21 > Message-ID: > < > CAK9RveLeh66nHX-ZBRpPs4mP+fDZ5JjwN3beVVRd8X0dnHCvRA(a)mail.gmail.com> > Content-Type: text/plain; charset="UTF-8" > > Em sex., 26 de mar. de 2021 ?s 12:22, prince raj via Boost < > boost(a)lists.boost.org> escreveu: > > > But I have no idea how to contact mentor for project discussion and my > > ideas with him. > > > > What's the project you're interested in? > > > -- > Vin?cius dos Santos Oliveira > https://vinipsmaker.github.io/ > > > ------------------------------ > > Message: 5 > Date: Fri, 26 Mar 2021 17:32:14 +0100 > From: Mateusz Loskot <mateusz(a)loskot.net> > To: boost(a)lists.boost.org > Subject: Re: [boost] To contact project's mentor for GSoC21 > Message-ID: > < > CABUeae8fsFiX6CS6_HXH-u59_GQJscbEdEJEZ-W0naq_WJRHiA(a)mail.gmail.com> > Content-Type: text/plain; charset="UTF-8" > > On Fri, 26 Mar 2021 at 16:22, prince raj via Boost > <boost(a)lists.boost.org> wrote: > > > > But I have no idea how to contact mentor for project discussion and my > > ideas with him. > > > > So please help me contacting to mentor so that I can make my proposal > > good to summit. > > First, read this and the materials linked there > https://github.com/boostorg/wiki/wiki/Google-Summer-of-Code%3A-Overview > > Best regards, > -- > Mateusz Loskot, http://mateusz.loskot.net > > > ------------------------------ > > Message: 6 > Date: Fri, 26 Mar 2021 19:45:39 -0700 > From: Christian Mazakas <christian.mazakas(a)gmail.com> > To: "boost(a)lists.boost.org List" <boost(a)lists.boost.org> > Cc: Peter Dimov <pdimov(a)gmail.com> > Subject: Re: [boost] [Lambda2] Review starts Monday March 22, 2021 to > March 31, 2021 > Message-ID: > < > CAHf7xWsqNHEt8-nxBRFz1+BjNMiwXasoYsFOuFR+tpd2EWZkog(a)mail.gmail.com> > Content-Type: text/plain; charset="UTF-8" > > Hey everyone, > > I vote to *ACCEPT *Lambda2. > > I first heard of Lambda2 when Peter asked me how many lines I thought > it would take to recreate Boost.Lambda. > > Naturally, I should've seen this as a loaded question but I guessed a few > hundred. Maybe something just below a couple thousand by the time all > the dust settles. > > Peter told me it could be done in ~50 lines. Now I was intrigued. The > source code of > Lambda2 is wonderfully clever and short. Moreso, sufficiently clever that > it's worth > not repeating every time we want to use it. > > Higher-order functions are all the rage in C++ and writing lambdas is > cumbersome > and annoying. Lambda2 gives us a C++14 solution that relies on nothing else > but > simple language features and stdlib headers making it faster to compile > than older > solutions such as Phoenix or the original Lambda. > > Lambda2 also has the fortune of interop'ing greatly with existing > constructs like > Boost.HOF and the new `<ranges>` STL header. See: > https://godbolt.org/z/hfxfhfEqv > > Keeping this short, Lambda2 gives us fresh paint over an old technology > that we know > works and one that (while polarizing in its style) does its job well. I > think it ultimately > serves Boost and the larger C++ community to keep this Lambda-style of > coding alive > and well-maintained as C++ evolves. > > - Christian > > > ------------------------------ > > Message: 7 > Date: Fri, 26 Mar 2021 23:18:47 -0700 > From: Emil Dotchevski <emildotchevski(a)gmail.com> > To: Boost <boost(a)lists.boost.org> > Subject: Re: [boost] [Boost] [Lambda2] Review starts Monday March 22, > 2021 to March 31, 2021 > Message-ID: > <CAN5fK5HJmHeZOoQ-nYwrHxKnQMjcAX8bLR4KMKz3= > QsXwrM-Pw(a)mail.gmail.com> > Content-Type: text/plain; charset="UTF-8" > > Here is my review of lambda2: > > I remember when I first learned boost::bind, and realized how much more > useful STL is because of it. Even after C++11 I still find myself using > bind, it sometimes looks more readable to my eyes than a lambda. > > The lambda2 library is one more proof for the solid design behind > std::bind. That, or std::bind was designed with things like lambda2 in > mind. Either way, lambda2 is an elegant utility for writing elegant C++, > albeit only in the (rare?) cases when it is a perfect fit. Given this, and > the miniature size of the library, my vote is to ACCEPT. > > > ------------------------------ > > Message: 8 > Date: Sat, 27 Mar 2021 17:42:36 +0000 > From: "Phil Endecott" <spam_from_boost_dev(a)chezphil.org> > To: <boost(a)lists.boost.org> > Subject: Re: [boost] [Lambda2] Review starts Monday March 22, 2021 to > March 31, 2021 > Message-ID: <1616866956454(a)dmwebmail.dmwebmail.chezphil.org> > Content-Type: text/plain; format="flowed"; charset="UTF-8" > > Peter Dimov wrote: > > The goals of the library are > > [...] > > - Prepare a proposal to extend the standard with these same additions by > > gathering experience in Boost first. > > Am I correct in thinking that this functionality could have been > added to the standard library when std::bind was added in C++11, > except that it requires something in the core language that was not > added until C++14 ? > > If not, what is the reason why this was not added when std::bind > was added? (I've failed to locate any pre-C++11 WG21 papers about > std::bind.) > > > Regards, Phil. > > > > > > > ------------------------------ > > Message: 9 > Date: Sat, 27 Mar 2021 19:58:03 +0200 > From: "Peter Dimov" <pdimov(a)gmail.com> > To: <boost(a)lists.boost.org> > Subject: Re: [boost] [Lambda2] Review starts Monday March 22, 2021 to > March 31, 2021 > Message-ID: <14fe01d72332$bc76fad0$3564f070$(a)gmail.com> > Content-Type: text/plain; charset="utf-8" > > Phil Endecott wrote: > > Peter Dimov wrote: > > > The goals of the library are > > > [...] > > > - Prepare a proposal to extend the standard with these same additions > by > > > gathering experience in Boost first. > > > > Am I correct in thinking that this functionality could have been added > to the > > standard library when std::bind was added in C++11, except that it > requires > > something in the core language that was not added until C++14 ? > > Return type deduction makes it easier to write, and the function objects in > <functional> acquired their <void> forms in C++14, but it's possible to > make > this work in C++11 as well. > > > If not, what is the reason why this was not added when std::bind was > added? > > (I've failed to locate any pre-C++11 WG21 papers about std::bind.) > > I didn't propose it. :-) > > > > ------------------------------ > > Message: 10 > Date: Sat, 27 Mar 2021 22:38:36 +0530 > From: sayan chaudhuri <sayanchaudhuri758(a)gmail.com> > To: boost(a)lists.boost.org > Subject: [boost] [Boost][GIL][GSOC 2021] Contribute to the library > Message-ID: > <CAJH= > o2N_rOMqaPg+jt823+Nj9Z+fD+w-4LqQw8ZOOBkEUMAUzw(a)mail.gmail.com> > Content-Type: text/plain; charset="UTF-8" > > Hello Everyone, > My name is Sayan Chaudhuri. I am a final > year,undergraduate student,in the Computer Science and Engineering > department of IEM,India . I am eager to participate in the GSOC 2021 and > willing to contribute to the Boost GIL library. > I have already gone through the wiki list of Boost > GIL listing the various image processing and computer vision algorithms > that have not been implemented yet. I have also gone through the > Contributing documents for BOOST GIL. . While going through the Boost > Mailing List Archives, I found that Igor Antropov had suggested to develop > ORB descriptor during his GSOC tenure but it has not been implemented yet.. > I am therefore eager to develop the ORB descriptor for Boost GIL during > GSOC 2021. ORB is useful in many situations like object recognition and > structure for motion and also it is suitable for real time applications > unlike SIFT and SURF. I also found out that while using Boost , everytime I > need to see the output , I need to save the output in order to view > it,thereby unnecessarily wasting memory when I do not wish to save the > output. So, the functionality of imshow() for OPENCV is missing for Boost > GIL. I am also eager to work on that functionality as well during GSOC > 2021. Would therefore anyone is interested in mentoring me? > As my programming competency test for Boost GIL, I > have implemented the KMeans algorithm from scratch using Boost GIL and I > have raised a pull request- https://github.com/boostorg/gil/pull/587. I > would kindly request if someone can kindly review it. Also, I would like to > know whether there are any similar issues that I can work on currently. > > > ------------------------------ > > Message: 11 > Date: Sun, 28 Mar 2021 03:22:35 +0000 > From: Suraj Nehra <surajnehra112(a)gmail.com> > To: boost(a)lists.boost.org > Subject: [boost] (no subject) > Message-ID: > <CAJR02FfuUhWpDYveadts9Xd5QD5_tzV5z= > hgMmar1greSBmzSw(a)mail.gmail.com> > Content-Type: text/plain; charset="UTF-8" > > Hi, > I am Suraj Nehra, a pre-final year student at the National Institute of > Technology (NIT), Warangal, India. This mail is to introduce myself to the > boost community. Boost.Real is not added to boost project ideas page yet > but I was discussing ideas with Vikram(vikram2000b(a)gmail.com) and also > made > several contributions to the library. > > I wish to work on this library in this GSoC and will start drafting > the proposal. I received the competency task from Vikram and will start > working on those. I was informed of the following potential ideas by him: > 1. Library comparison and benchmarking with other similar libraries. > 2. DAG internal representation > 3. Propose and implement optimizations for trigonometric functions. > > I wish to work on ideas 1 and 3. I will start making the proposal for these > ideas and share the draft with you. > It will be a pleasure to hear any suggestions and guidance from you. > > Thanks & Regards > Suraj Nehra > > > ------------------------------ > > Message: 12 > Date: Sun, 28 Mar 2021 03:30:54 +0000 > From: Suraj Nehra <surajnehra112(a)gmail.com> > To: boost(a)lists.boost.org > Subject: [boost] [GSoC] Boost.Real: Introduction and Guidence > Message-ID: > < > CAJR02Fe4w-FfDcjDK4NfLs1LNqBwThi5uxF-nhefMo6NhrSSkw(a)mail.gmail.com> > Content-Type: text/plain; charset="UTF-8" > > Hi, > I am Suraj Nehra, a pre-final year student at the National Institute of > Technology (NIT), Warangal, India. This mail is to introduce myself to the > boost community. Boost.Real is not added to boost project ideas page yet > but I was discussing ideas with Vikram(vikram2000b(a)gmail.com) and also > made > several contributions to the library. > > I wish to work on this library in this GSoC and will start drafting > the proposal. I received the competency task from Vikram and will start > working on those. I was informed of the following potential ideas by him: > 1. Library comparison and benchmarking with other similar libraries. > 2. DAG internal representation > 3. Propose and implement optimizations for trigonometric functions. > > I wish to work on ideas 1 and 3. I will start making the proposal for these > ideas and share the draft with you. > It will be a pleasure to hear any suggestions and guidance from you. > > Thanks & Regards > Suraj Nehra > > > ------------------------------ > > Message: 13 > Date: Sun, 28 Mar 2021 09:54:11 +0300 > From: Antony Polukhin <antoshkka(a)gmail.com> > To: "boost(a)lists.boost.org List" <boost(a)lists.boost.org> > Subject: [boost] Changelog for 1.76 is outdated > Message-ID: > < > CAKqmYPazb_JKWwwy-DZGdpfseJ4wB0KXR3FsK22o-nZ0w6G+0Q(a)mail.gmail.com> > Content-Type: text/plain; charset="UTF-8" > > Hi, > > The https://www.boost.org/users/history/version_1_76_0.html seems quite > outdated. Please update > > Thanks in advance! > > > ------------------------------ > > Message: 14 > Date: Sun, 28 Mar 2021 09:56:43 +0300 > From: Antony Polukhin <antoshkka(a)gmail.com> > To: "boost(a)lists.boost.org List" <boost(a)lists.boost.org> > Subject: Re: [boost] Changelog for 1.76 is outdated > Message-ID: > <CAKqmYPaXN-c= > k45pCMWVDYAdHX+p916H2fjkfHXZ4pvVchRV6A(a)mail.gmail.com> > Content-Type: text/plain; charset="UTF-8" > > By "outdated" I mean that > > https://github.com/boostorg/website/blob/master/feed/history/boost_1_76_0.q… > has more info > > > ------------------------------ > > Message: 15 > Date: Sun, 28 Mar 2021 15:05:07 +0200 > From: shady mohamed <shadimabdrawy1999(a)gmail.com> > To: boost(a)lists.boost.org > Subject: Re: [boost] Boost Digest, Vol 6566, Issue 1 > Message-ID: > < > CAPwR5ipUjbt4R5E_W4qO3wvfkm7NfmiT1Q99AhMwWvGxTUyk2A(a)mail.gmail.com> > Content-Type: text/plain; charset="UTF-8" > > I want to talk with engineer david bellot and engineer cem bassoy > Thanks > > ?? ??????? ?? ????? ???? ??:?? ? <boost-request(a)lists.boost.org> ???: > > > Send Boost mailing list submissions to > > boost(a)lists.boost.org > > > > To subscribe or unsubscribe via the World Wide Web, visit > > https://lists.boost.org/mailman/listinfo.cgi/boost > > or, via email, send a message with subject or body 'help' to > > boost-request(a)lists.boost.org > > > > You can reach the person managing the list at > > boost-owner(a)lists.boost.org > > > > When replying, please edit your Subject line so it is more specific > > than "Re: Contents of Boost digest..." > > > > > > The boost archives may be found at: > http://lists.boost.org/Archives/boost/ > > > > > > Today's Topics: > > > > 1. Re: [Boost] [Lambda2] Review starts Monday March 22, 2021 to > > March 31, 2021 (Andrzej Krzemienski) > > 2. Re: [release] 1.76.0 post-beta merges (Niall Douglas) > > 3. Re: [Boost] [Lambda2] Review starts Monday March 22, 2021 to > > March 31, 2021 (Peter Dimov) > > 4. Re: [release] 1.76.0 post-beta merges (Marshall Clow) > > 5. Re: [release] 1.76.0 post-beta merges (Niall Douglas) > > 6. Re: [release] 1.76.0 post-beta merges (Glen Fernandes) > > 7. Re: [Lambda2] Review starts Monday March 22, 2021 to March > > 31, 2021 (Julien Blanc) > > 8. Re: [Lambda2] Review starts Monday March 22, 2021 to March > > 31, 2021 (Andrzej Krzemienski) > > 9. Re: [Lambda2] Review starts Monday March 22, 2021 to March > > 31, 2021 (Julien Blanc) > > 10. Re: [Boost] [Describe] Summary Review Summary (Emil Dotchevski) > > 11. Re: [Lambda2] Review starts Monday March 22, 2021 to March > > 31, 2021 (Mathias Gaunard) > > 12. Re: [Boost] [Lambda2] Review starts Monday March 22, 2021 to > > March 31, 2021 (Mathias Gaunard) > > > > > > ---------------------------------------------------------------------- > > > > Message: 1 > > Date: Thu, 25 Mar 2021 14:54:17 +0100 > > From: Andrzej Krzemienski <akrzemi1(a)gmail.com> > > To: Boost mailing list <boost(a)lists.boost.org> > > Cc: Peter Dimov <pdimov(a)gmail.com> > > Subject: Re: [boost] [Boost] [Lambda2] Review starts Monday March 22, > > 2021 to March 31, 2021 > > Message-ID: > > <CAOenAXhsJ1yCRRBYgJuPh8xws5MMVCks7p6GvfmBG+= > > 28QDNPg(a)mail.gmail.com> > > Content-Type: text/plain; charset="UTF-8" > > > > pon., 22 mar 2021 o 16:44 Peter Dimov via Boost <boost(a)lists.boost.org> > > napisa?(a): > > > > > Edward Diener wrote: > > > > My first reaction, after quickly looking at the submission, is what > > does > > > this > > > > library offer that the original lambda library, which appears to > have a > > > much > > > > larger amount of functionality than this lambda2 library, not offer ? > > > Also there > > > > is the Phoenix library, which also offers an even greater amount of > > > function > > > > object and lambda-like functionality, of which the review manager is > > the > > > main > > > > author I believe. > > > > > > Purely from a user perspective, what this library offers is being a > > > lightweight, > > > single header dependency, and... > > > > > > > Is it basically so that the programmer can easily interface with > > > > the std::bind/std::function classes with the lambda2 placeholders, > > > whereas the > > > > C++03 libraries don't have this possibility wit their placeholders ? > > > > > > ... indeed, a way to port boost::bind code that uses its operators to > > > std::bind, > > > something that comes up from time to time as projects are modernized. > > > > > > From a different perspective, another goal of the submission is to > gather > > > experience and provide a tested and widely available implementation for > > an > > > eventual proposal to add this functionality to the standard. (Better > late > > > than > > > never.) > > > > > > > My opinion so far is that there is not enough motivation to warrant the > > addition of this library into Boost. > > > > First, the design goals, or the purpose, of the library is not clearly > > defined. > > > > Is the goal that tandem std::bind + Boost.Lambda2 should be a replacement > > over boost::bind and Boost.Lambda? If so, in the current form of the > > library the goal will not be satisfied, because current Boost.Lambda > offers > > quite more things. Just look at the motivating examples of Boost.Lambda: > > https://www.boost.org/doc/libs/1_75_0/doc/html/lambda/using_library.html > > In particular, the usage of assignment or function constant(). > > Boost.Lambda2 will not work as a drop-in replacement for Boost.Lambda. > > > > For a moment I thought that the goal is to have a cooler syntax for the > > current standard arithmetic function objects, such as std::plus, > > std::multiplies. But the advantage is dubious. You gain a few characters, > > but you pay the cost of > > * employing a different library > > * messy error messages > > * no debugger support > > > > The suggestion that we would enable constructs like > > `std::bind(&Employee::name, e1) < std::bind(&Employee::name, e2)`also > > doesn't seem like a good motivation. std::bind only works well when it is > > used for binding arguments to functions. Overusing it for implementing > > lambdas made sense in C++03, because there was no other way. Now with > > generic lambdas it can only be considered a bad (or at least > controversial) > > practice. > > > > I am far from imposing my programming style on others. But promoting a > > programming style like this through the inclusion into Boost seems too > > much. My vision of Boost is that it should support certain programming > > styles that are considered good, but not any programming style. > > > > Regarding the implementation, on the other hand, it is as elegant as a > > library implementation could ever be. It is extremely short! (78 lines, > > including whitespace, header guards, and copyright notice). > > > > Regards, > > &rzej; > > > > > > ------------------------------ > > > > Message: 2 > > Date: Thu, 25 Mar 2021 15:06:02 +0000 > > From: Niall Douglas <s_sourceforge(a)nedprod.com> > > To: boost(a)lists.boost.org > > Subject: Re: [boost] [release] 1.76.0 post-beta merges > > Message-ID: <6efb04af-9f26-4d04-a187-8bc08369caf3(a)nedprod.com> > > Content-Type: text/plain; charset=utf-8 > > > > On 16/03/2021 20:24, Marshall Clow via Boost wrote: > > > The master branch is is now open for post-beta merges, but only as > > described in the Post-Beta Merge Policy. > > > See < > > https://github.com/boostorg/boost/wiki/Releases%3A-Beta-Merge-Policy> > > > > I would like to fix https://github.com/ned14/outcome/issues/249 by > > improving the logic at > > > > > https://github.com/ned14/outcome/blob/develop/include/outcome/convert.hpp#L… > > please. > > > > Niall > > > > > > ------------------------------ > > > > Message: 3 > > Date: Thu, 25 Mar 2021 17:24:15 +0200 > > From: "Peter Dimov" <pdimov(a)gmail.com> > > To: "'Andrzej Krzemienski'" <akrzemi1(a)gmail.com>, "'Boost mailing > > list'" <boost(a)lists.boost.org> > > Subject: Re: [boost] [Boost] [Lambda2] Review starts Monday March 22, > > 2021 to March 31, 2021 > > Message-ID: <131601d7218a$eb1033b0$c1309b10$(a)gmail.com> > > Content-Type: text/plain; charset="utf-8" > > > > Andrzej Krzemienski wrote: > > > First, the design goals, or the purpose, of the library is not clearly > > defined. > > > > The goals of the library are > > > > - Give people the choice of using an abbreviated lambda syntax that is > able > > to express simple operations in fewer characters; > > - Bring std::bind to parity with boost::bind feature-wise so that porting > > is > > easier; > > - Prepare a proposal to extend the standard with these same additions by > > gathering experience in Boost first. > > > > > Is the goal that tandem std::bind + Boost.Lambda2 should be a > replacement > > > over boost::bind and Boost.Lambda? If so, in the current form of the > > library > > > the goal will not be satisfied, because current Boost.Lambda offers > > quite more > > > things. > > > > This doesn't make it useless. When porting "operator-enhanced" > boost::bind, > > or Boost.Lambda, code, you need to go over all the uses and change them > > into language lambdas. This is routine mechanical work that as a result > is > > highly error-prone and without good test coverage, mistakes can easily > pass > > review because of the repetitive nature of the diff. It's much better if > > you > > could port at least some of the uses without making changes beyond > > replacing > > boost:: with std::, and adding/changing the using directive. > > > > It's not necessary to be able to port _all_ uses without any changes; a > > portion > > is enough to reduce the error rate significantly. > > > > And if you're going to ask what's the point of porting from one Boost > > library > > to another, the difference is that it's much easier to "vendor" a single > > short > > header. > > > > > For a moment I thought that the goal is to have a cooler syntax for the > > current > > > standard arithmetic function objects, such as std::plus, > > std::multiplies. But the > > > advantage is dubious. You gain a few characters, but you pay the cost > of > > > * employing a different library > > > * messy error messages > > > * no debugger support > > > > This could be true, but it has nothing to do with the library lacking > > clarity of > > purpose. > > > > > The suggestion that we would enable constructs like > > > `std::bind(&Employee::name, e1) < std::bind(&Employee::name, e2)`also > > > doesn't seem like a good motivation. > > > > As explained, this is only an issue when porting boost::bind code using > > these constructs. You obviously aren't going to use this in new code > > because > > the equivalent language lambda is shorter (not by much) and clearer. > > > > > > > > ------------------------------ > > > > Message: 4 > > Date: Thu, 25 Mar 2021 08:45:22 -0700 > > From: Marshall Clow <mclow.lists(a)gmail.com> > > To: Boost Developers List <boost(a)lists.boost.org> > > Subject: Re: [boost] [release] 1.76.0 post-beta merges > > Message-ID: <0EAF569D-A080-4217-BC77-D7CE4057EC0A(a)gmail.com> > > Content-Type: text/plain; charset=utf-8 > > > > On Mar 25, 2021, at 8:06 AM, Niall Douglas via Boost < > > boost(a)lists.boost.org> wrote: > > > > > > On 16/03/2021 20:24, Marshall Clow via Boost wrote: > > >> The master branch is is now open for post-beta merges, but only as > > described in the Post-Beta Merge Policy. > > >> See < > > https://github.com/boostorg/boost/wiki/Releases%3A-Beta-Merge-Policy> > > > > > > I would like to fix https://github.com/ned14/outcome/issues/249 by > > > improving the logic at > > > > > > https://github.com/ned14/outcome/blob/develop/include/outcome/convert.hpp#L… > > > please. > > > > Do you have a commit that fixes this? > > > > ? Marshall > > > > > > > > > > ------------------------------ > > > > Message: 5 > > Date: Thu, 25 Mar 2021 16:04:17 +0000 > > From: Niall Douglas <s_sourceforge(a)nedprod.com> > > To: Boost Developers List <boost(a)lists.boost.org> > > Subject: Re: [boost] [release] 1.76.0 post-beta merges > > Message-ID: <2dc9222a-592a-6b85-c76b-d62ef55611b3(a)nedprod.com> > > Content-Type: text/plain; charset=utf-8 > > > > On 25/03/2021 15:45, Marshall Clow wrote: > > > On Mar 25, 2021, at 8:06 AM, Niall Douglas via Boost < > > boost(a)lists.boost.org> wrote: > > >> > > >> On 16/03/2021 20:24, Marshall Clow via Boost wrote: > > >>> The master branch is is now open for post-beta merges, but only as > > described in the Post-Beta Merge Policy. > > >>> See < > > https://github.com/boostorg/boost/wiki/Releases%3A-Beta-Merge-Policy> > > >> > > >> I would like to fix https://github.com/ned14/outcome/issues/249 by > > >> improving the logic at > > >> > > > https://github.com/ned14/outcome/blob/develop/include/outcome/convert.hpp#L… > > >> please. > > > > > > Do you have a commit that fixes this? > > > > The change is trivial. Current: > > > > ```c++ > > #if !defined(_MSC_VER) && !defined(__clang__) && (__GNUC__ < 9 || > > __cpp_concepts < 201907L) > > #define OUTCOME_GCC6_CONCEPT_BOOL bool > > #else > > #define OUTCOME_GCC6_CONCEPT_BOOL > > #endif > > ``` > > > > To be replaced with: > > > > ```c++ > > #if (defined(_MSC_VER) || defined(__clang__) || (defined(__GNUC__) && > > __cpp_concepts >= 201707) || OUTCOME_FORCE_STD_CXX_CONCEPTS) && > > !OUTCOME_FORCE_LEGACY_GCC_CXX_CONCEPTS > > #define OUTCOME_GCC6_CONCEPT_BOOL > > #else > > #define OUTCOME_GCC6_CONCEPT_BOOL bool > > #endif > > ``` > > > > To explain, GCC expects bool with concept, or not, in varying > > configuration combinations which have evolved over GCC versions, > > including apparently point releases, which is deeply unhelpful. This has > > led to repeated bug reports for not just Outcome, but also for ASIO and > > many other C++ projects. > > > > If this above fix doesn't permanently shut this constant source of bug > > reports, I'll be permanently disabling legacy GCC concepts support in > > Outcome. I couldn't be arsed with supporting how unpredictably broken > > GCC is with this. > > > > Niall > > > > > > ------------------------------ > > > > Message: 6 > > Date: Thu, 25 Mar 2021 12:12:03 -0400 > > From: Glen Fernandes <glen.fernandes(a)gmail.com> > > To: boost(a)lists.boost.org > > Subject: Re: [boost] [release] 1.76.0 post-beta merges > > Message-ID: > > <CAHVPgznFdSVYJ9gR8LzP7qQV7w5+fcjBvKq95ReUKkFR-ct= > > Qg(a)mail.gmail.com> > > Content-Type: text/plain; charset="UTF-8" > > > > On Thu, Mar 25, 2021 at 12:04 PM Niall Douglas via Boost > > <boost(a)lists.boost.org> wrote: > > > > > > On 25/03/2021 15:45, Marshall Clow wrote: > > > > On Mar 25, 2021, at 8:06 AM, Niall Douglas via Boost < > > boost(a)lists.boost.org> wrote: > > > >> > > > >> I would like to fix https://github.com/ned14/outcome/issues/249 by > > > >> improving the logic at > > > >> > > > https://github.com/ned14/outcome/blob/develop/include/outcome/convert.hpp#L… > > > >> please. > > > > > > > > Do you have a commit that fixes this? > > > > > > The change is trivial. Current: > > > > If you're asking for permission to merge to master now, you should > > have a commit on outcome's develop branch that we can look at. You are > > free to commit to develop at any time. Only master is locked. > > > > Glen > > > > > > ------------------------------ > > > > Message: 7 > > Date: Thu, 25 Mar 2021 19:10:33 +0100 > > From: Julien Blanc <julien.blanc(a)tgcm.eu> > > To: boost(a)lists.boost.org > > Subject: Re: [boost] [Lambda2] Review starts Monday March 22, 2021 to > > March 31, 2021 > > Message-ID: <2773cbf43ec651fdf2b3a3262c8476d814047eb0.camel(a)tgcm.eu> > > Content-Type: text/plain; charset="UTF-8" > > > > Le lundi 22 mars 2021 ? 10:35 +0800, Joel de Guzman via Boost a ?crit?: > > > The Boost formal review of the Lambda2, authored by Peter Dimov, > > > starts Monday, March 22, 2021 to March 31, 2021 (inclusive). > > > > Here's my small review of the lambda 2 library. > > > > TLDR: ACCEPT > > > > > ?? - What is your evaluation of the design? > > > ?? - What is your evaluation of the implementation? > > > > The library is a really small piece of code, like other reviewers > > already noticed. During my tests, i came across two things that could > > be improved: > > * the internal macro BOOST_LAMBDA2_UNARY_LAMBDA and > > BOOST_LAMBDA2_BINARY_LAMBDA #undefed at the end of the file. While i > > undestand that it is an internal macro, it could be exposed to the user > > to allow implementation for other operators > > * that macro hardcode the std prefix, it could be part of its call, ie: > > > > BOOST_LAMBDA2_BINARY_LAMBDA(+, std::plus) // instead of > > BOOST_LAMBDA2_BINARY_LAMBDA(+, plus) > > > > This would allow the user of the library to get the building blocks to > > customize other operators to its needs (I have implemented unary > > operator* easily that way). > > > > > ?? - What is your evaluation of the documentation? > > > > The documentation is really good at telling what the library does, is > > clean, nice looking. > > > > > ?? - What is your evaluation of the potential usefulness of the > > > library? > > > > At first glance, i was thinking that this was the kind of library that > > i would never use. I find the count_if examples in the documentation > > not really convincing. > > > > Then, it happened that i made some experiments with c++20 ranges. And i > > find that, in this context, shortening the lambdas gives a real benefit > > to the code. It basically started from the need to feed a function that > > was needing a list of non owner references to T from a > > vector<unique_ptr<T>>. As I was not satisfied with the solution, I > > checked whether c++20 ranges could provide an elegant solution to this. > > Something like > > > > f(std::views::transform(vec, deref)); > > > > implementing deref is easy. Then, out of curiosity, i checked if i > > could use Peter's library to be able to write something like: > > > > f(std::views::transform(vec, *_1)); > > > > I actually find that this way of writing is more natural than the > > former. > > > > So, i wrote : > > > > namespace std // BAD, don't do that > > { > > template<typename T = void> > > struct deref > > { > > decltype(auto) operator()(T& v) { return *v; } > > }; > > template<> > > struct deref<void> > > { > > template<typename T> > > decltype(auto) operator()(T& v) { return *v; } > > }; > > } > > > > BOOST_LAMBDA2_UNARY_LAMBDA(*, deref); > > > > modified Peter's library to remove the #undef, and voila, it just > > works. > > > > I see a lot of potential for the short writing form for lambdas, in > > conjunction with the ranges library. I find convenient to write: > > > > f(std::views::transform(vec, _1 + 1)) // convert from 0-based to 1- > > based index > > > > > ?? - Did you try to use the library? With which compiler(s)? Did you > > > ???? have any problems? > > > > No specific issue encountered, with gcc-10. Error messages are a bit > > cryptic. > > > > > ?? - How much effort did you put into your evaluation? A glance? A > > > quick > > > ???? reading? In-depth study? > > > > A few hours playing with the library. > > > > > ?? - Are you knowledgeable about the problem domain? > > > > Not at all. > > > > My feeling is the following. At first glance, i was wondering what was > > the use case the library addressed. After playing a bit with it, i'm > > now convinced that people will want to use it, and, like me, will > > probably want to expand it to fit their need. I was not suspecting that > > it was possible to write code that way. I suspect most developers are > > not either. Now that it is known it's possible, people will come up > > with their own, probably inferior, solution. Having such a feature in > > boost would at least provide everyone with a correct implementation of > > it. Because people will want to write code like this, and i believe, > > especially with ranges. > > > > Thanks to Peter for writing this library, and proposing it to boost. > > Reviewing it has been very interesting and instructive. > > > > Regards, > > > > Julien > > > > > > > > ------------------------------ > > > > Message: 8 > > Date: Fri, 26 Mar 2021 05:54:36 +0100 > > From: Andrzej Krzemienski <akrzemi1(a)gmail.com> > > To: Boost mailing list <boost(a)lists.boost.org> > > Subject: Re: [boost] [Lambda2] Review starts Monday March 22, 2021 to > > March 31, 2021 > > Message-ID: > > <CAOenAXgEDx= > > kmKY5gVdST-oAeipoa2oG2s5j_y0brxs34r7ojw(a)mail.gmail.com> > > Content-Type: text/plain; charset="UTF-8" > > > > czw., 25 mar 2021 o 19:11 Julien Blanc via Boost <boost(a)lists.boost.org> > > napisa?(a): > > > > > Le lundi 22 mars 2021 ? 10:35 +0800, Joel de Guzman via Boost a ?crit : > > > > The Boost formal review of the Lambda2, authored by Peter Dimov, > > > > starts Monday, March 22, 2021 to March 31, 2021 (inclusive). > > > > > > Here's my small review of the lambda 2 library. > > > > > > TLDR: ACCEPT > > > > > > > - What is your evaluation of the design? > > > > - What is your evaluation of the implementation? > > > > > > The library is a really small piece of code, like other reviewers > > > already noticed. During my tests, i came across two things that could > > > be improved: > > > * the internal macro BOOST_LAMBDA2_UNARY_LAMBDA and > > > BOOST_LAMBDA2_BINARY_LAMBDA #undefed at the end of the file. While i > > > undestand that it is an internal macro, it could be exposed to the user > > > to allow implementation for other operators > > > * that macro hardcode the std prefix, it could be part of its call, ie: > > > > > > BOOST_LAMBDA2_BINARY_LAMBDA(+, std::plus) // instead of > > > BOOST_LAMBDA2_BINARY_LAMBDA(+, plus) > > > > > > This would allow the user of the library to get the building blocks to > > > customize other operators to its needs (I have implemented unary > > > operator* easily that way). > > > > > > > Is it not just that the library is missing some operators? If > Boost.Lambda2 > > overloaded all overloadable operators there would be no point in users > > doing it. > > > > > > > > - What is your evaluation of the documentation? > > > > > > The documentation is really good at telling what the library does, is > > > clean, nice looking. > > > > > > > - What is your evaluation of the potential usefulness of the > > > > library? > > > > > > At first glance, i was thinking that this was the kind of library that > > > i would never use. I find the count_if examples in the documentation > > > not really convincing. > > > > > > Then, it happened that i made some experiments with c++20 ranges. And i > > > find that, in this context, shortening the lambdas gives a real benefit > > > to the code. It basically started from the need to feed a function that > > > was needing a list of non owner references to T from a > > > vector<unique_ptr<T>>. As I was not satisfied with the solution, I > > > checked whether c++20 ranges could provide an elegant solution to this. > > > Something like > > > > > > f(std::views::transform(vec, deref)); > > > > > > implementing deref is easy. Then, out of curiosity, i checked if i > > > could use Peter's library to be able to write something like: > > > > > > f(std::views::transform(vec, *_1)); > > > > > > I actually find that this way of writing is more natural than the > > > former. > > > > > > > This is an interesting observation. In my experience, storing collections > > of ints is a rare case in production code (it is frequent in tests, > > tutorials, books, presentations), maybe this is why arithmetic operators > do > > not appear as something practical. However pointers (including smart > ones) > > to user-defined types is something that I see a lot. The following als > > looks as something I would see often in the code: > > > > assert(std::ranges::all_of(records, _1 != nullptr)); > > > > Regards, > > &rzej; > > > > > > > So, i wrote : > > > > > > namespace std // BAD, don't do that > > > { > > > template<typename T = void> > > > struct deref > > > { > > > decltype(auto) operator()(T& v) { return *v; } > > > }; > > > template<> > > > struct deref<void> > > > { > > > template<typename T> > > > decltype(auto) operator()(T& v) { return *v; } > > > }; > > > } > > > > > > BOOST_LAMBDA2_UNARY_LAMBDA(*, deref); > > > > > > modified Peter's library to remove the #undef, and voila, it just > > > works. > > > > > > I see a lot of potential for the short writing form for lambdas, in > > > conjunction with the ranges library. I find convenient to write: > > > > > > f(std::views::transform(vec, _1 + 1)) // convert from 0-based to 1- > > > based index > > > > > > > - Did you try to use the library? With which compiler(s)? Did you > > > > have any problems? > > > > > > No specific issue encountered, with gcc-10. Error messages are a bit > > > cryptic. > > > > > > > - How much effort did you put into your evaluation? A glance? A > > > > quick > > > > reading? In-depth study? > > > > > > A few hours playing with the library. > > > > > > > - Are you knowledgeable about the problem domain? > > > > > > Not at all. > > > > > > My feeling is the following. At first glance, i was wondering what was > > > the use case the library addressed. After playing a bit with it, i'm > > > now convinced that people will want to use it, and, like me, will > > > probably want to expand it to fit their need. I was not suspecting that > > > it was possible to write code that way. I suspect most developers are > > > not either. Now that it is known it's possible, people will come up > > > with their own, probably inferior, solution. Having such a feature in > > > boost would at least provide everyone with a correct implementation of > > > it. Because people will want to write code like this, and i believe, > > > especially with ranges. > > > > > > Thanks to Peter for writing this library, and proposing it to boost. > > > Reviewing it has been very interesting and instructive. > > > > > > Regards, > > > > > > Julien > > > > > > > > > _______________________________________________ > > > Unsubscribe & other changes: > > > http://lists.boost.org/mailman/listinfo.cgi/boost > > > > > > > > > ------------------------------ > > > > Message: 9 > > Date: Fri, 26 Mar 2021 07:44:43 +0100 > > From: Julien Blanc <julien.blanc(a)tgcm.eu> > > To: boost(a)lists.boost.org > > Subject: Re: [boost] [Lambda2] Review starts Monday March 22, 2021 to > > March 31, 2021 > > Message-ID: <54d581dd2987773250b0f822393ea819a03297bc.camel(a)tgcm.eu> > > Content-Type: text/plain; charset="UTF-8" > > > > Le vendredi 26 mars 2021 ? 05:54 +0100, Andrzej Krzemienski via Boost a > > ?crit?: > > > > This would allow the user of the library to get the building blocks > > > > to > > > > customize other operators to its needs (I have implemented unary > > > > operator* easily that way). > > > > > > > > > > Is it not just that the library is missing some operators? If > > > Boost.Lambda2 > > > overloaded all overloadable operators there would be no point in > > > users > > > doing it. > > > > Agreed. But I don't have a strong opinion on whether the library should > > implement everything, or just be more open to user extensions. > > > > > The following als looks as something I would see often in the code: > > > > > > assert(std::ranges::all_of(records, _1 != nullptr)); > > > > Definitely. That's the kind of motivating example that i think should > > appear in the documentation. > > > > Regards, > > > > Julien > > > > > > > > ------------------------------ > > > > Message: 10 > > Date: Fri, 26 Mar 2021 00:23:56 -0700 > > From: Emil Dotchevski <emildotchevski(a)gmail.com> > > To: Boost <boost(a)lists.boost.org> > > Subject: Re: [boost] [Boost] [Describe] Summary Review Summary > > Message-ID: > > < > > CAN5fK5H0Cr5OmaX2ryTjRcboLu8xqiv3eKuYdCaft6EZXKFh9Q(a)mail.gmail.com> > > Content-Type: text/plain; charset="UTF-8" > > > > On Wed, Mar 24, 2021 at 7:35 AM Jeff Garland via Boost < > > boost(a)lists.boost.org> wrote: > > > > The committee seems to be concerned more with internal and external > > > > politics than with serving the community. If that wasn't true there > > would > > > > be ZERO library additions that haven't been battle hardened by being > > > > deployed and established themselves as the defacto standard already. > > > > > > Unlike the boost review where there's 'a decider', the committee uses > > > consensus. It's a much higher bar, as frankly, it should be. > > > > A "much higher bar" can prevent a good library from being accepted or > > prevent a bad library from being rejected. That is, consensus cuts both > > ways. > > > > > As for battle hardened, sometimes it's not quite so simple as sometimes > > > language changes are needed or vendor support is needed. Every > proposal > > > gets vetted for usage experience and it's clear that without experience > > > it's unlikely to go forward. Is the process perfect -- no. Will it > make > > > everyone, even the members happy -- no. Can it be improved -- surely > -- > > > but like many things in life it's not as simple as we'd like. > > > > We can talk about the case when language changes are needed but let's > focus > > on libraries. > > > > > > The only thing they should be doing is rubber-stamping libraries that > > are > > > > already the standard for doing something. > > > > > > And if we 'just did that', things like generic programming wouldn't > exist > > > in c++. If the 'Roque Wave' container design was adopted in 1998 the > > world > > > would be very different now. > > > > There was no GitHub in 1998. Today it feels like some authors treat the > > standard library as a vehicle for making their library available > everywhere > > in hopes it'll get adopted. All I'm saying is that adoption should come > > before standardization. Git pull requests are better than Subversion > > commits. > > > > > And if you want one of those 'battle hardened' libraries > > > adopted, that's fine > > > > You see, I think it is problematic to "want" to standardize a library. > IMO > > the standardization process should be dull and boring, rather than driven > > by exciting innovation. > > > > > > ------------------------------ > > > > Message: 11 > > Date: Fri, 26 Mar 2021 10:11:43 +0000 > > From: Mathias Gaunard <mathias.gaunard(a)ens-lyon.org> > > To: Boost mailing list <boost(a)lists.boost.org> > > Subject: Re: [boost] [Lambda2] Review starts Monday March 22, 2021 to > > March 31, 2021 > > Message-ID: > > <CALnjya9TV+n=N-0_8zWsu_+zGTAW= > > xezCsQ4C3vnBU6wZ6LkNw(a)mail.gmail.com> > > Content-Type: text/plain; charset="UTF-8" > > > > On Fri, 26 Mar 2021 at 04:54, Andrzej Krzemienski via Boost > > <boost(a)lists.boost.org> wrote: > > > > > > This is an interesting observation. In my experience, storing > collections > > > of ints is a rare case in production code (it is frequent in tests, > > > tutorials, books, presentations), maybe this is why arithmetic > operators > > do > > > not appear as something practical. > > > > They do appear frequently if you use column-oriented data structures, > > which are generally better at dealing with large collections of data. > > > > > > ------------------------------ > > > > Message: 12 > > Date: Fri, 26 Mar 2021 10:16:17 +0000 > > From: Mathias Gaunard <mathias.gaunard(a)ens-lyon.org> > > To: Boost mailing list <boost(a)lists.boost.org> > > Subject: Re: [boost] [Boost] [Lambda2] Review starts Monday March 22, > > 2021 to March 31, 2021 > > Message-ID: > > < > > CALnjya8bbeFs1d4q2pSbr8azU3aELbXVDtyCDtj+xioUDdkaEw(a)mail.gmail.com> > > Content-Type: text/plain; charset="UTF-8" > > > > On Mon, 22 Mar 2021 at 02:35, Joel de Guzman via Boost > > <boost(a)lists.boost.org> wrote: > > > > > > The Boost formal review of the Lambda2, authored by Peter Dimov, > > > starts Monday, March 22, 2021 to March 31, 2021 (inclusive). > > > > > > Documentation: https://pdimov.github.io/lambda2/doc/html/lambda2.html > > > Source: https://github.com/pdimov/lambda2/ > > > > > > Lambda2 is a simple, but functional, C++14 lambda library. It takes > > advantage > > > of the fact that the standard <functional> header already provides > > placeholders > > > _1, _2, _3, and so on, for use with std::bind, and function objects > such > > > as std::plus, std::greater, std::logical_not, and std::bit_xor, > > corresponding to > > > arithmetic, relational, logical and bitwise operators. > > > > > > Please provide in your review information you think is valuable to > > > understand your choice to ACCEPT or REJECT including Lambda2 as a > > > Boost library. Please be explicit about your decision (ACCEPT or > REJECT). > > > > > > Some other questions you might want to consider answering: > > > > > > - What is your evaluation of the design? > > > - What is your evaluation of the implementation? > > > - What is your evaluation of the documentation? > > > > It is not clear from the documentation what the capture behaviour of > > terminals is. > > I assume it's capturing rvalues by value and lvalues by reference? > > > > What about the expression tree itself, is it fully by value, and > > therefore safely copyable? > > Boost.Proto for example by default is binding everything by reference, > > meaning that you couldn't even store the expression in a variable. Is > > it avoiding this issue? > > > > > > ------------------------------ > > > > Subject: Digest Footer > > > > _______________________________________________ > > Unsubscribe & other changes: > > http://lists.boost.org/mailman/listinfo.cgi/boost > > > > > > ------------------------------ > > > > End of Boost Digest, Vol 6566, Issue 1 > > ************************************** > > > > > ------------------------------ > > Subject: Digest Footer > > _______________________________________________ > Unsubscribe & other changes: > http://lists.boost.org/mailman/listinfo.cgi/boost > > > ------------------------------ > > End of Boost Digest, Vol 6567, Issue 1 > ************************************** >

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Changelog for 1.76 is outdated
by Antony Polukhin 28 Mar '21

28 Mar '21

Hi, The https://www.boost.org/users/history/version_1_76_0.html seems quite outdated. Please update Thanks in advance!

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Re: [boost] Boost Digest, Vol 6566, Issue 1
by shady mohamed 28 Mar '21

28 Mar '21

I want to talk with engineer david bellot and engineer cem bassoy Thanks في الجمعة، ٢٦ مارس، ٢٠٢١ ١٢:٢٣ م <boost-request(a)lists.boost.org> كتب: > Send Boost mailing list submissions to > boost(a)lists.boost.org > > To subscribe or unsubscribe via the World Wide Web, visit > https://lists.boost.org/mailman/listinfo.cgi/boost > or, via email, send a message with subject or body 'help' to > boost-request(a)lists.boost.org > > You can reach the person managing the list at > boost-owner(a)lists.boost.org > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of Boost digest..." > > > The boost archives may be found at: http://lists.boost.org/Archives/boost/ > > > Today's Topics: > > 1. Re: [Boost] [Lambda2] Review starts Monday March 22, 2021 to > March 31, 2021 (Andrzej Krzemienski) > 2. Re: [release] 1.76.0 post-beta merges (Niall Douglas) > 3. Re: [Boost] [Lambda2] Review starts Monday March 22, 2021 to > March 31, 2021 (Peter Dimov) > 4. Re: [release] 1.76.0 post-beta merges (Marshall Clow) > 5. Re: [release] 1.76.0 post-beta merges (Niall Douglas) > 6. Re: [release] 1.76.0 post-beta merges (Glen Fernandes) > 7. Re: [Lambda2] Review starts Monday March 22, 2021 to March > 31, 2021 (Julien Blanc) > 8. Re: [Lambda2] Review starts Monday March 22, 2021 to March > 31, 2021 (Andrzej Krzemienski) > 9. Re: [Lambda2] Review starts Monday March 22, 2021 to March > 31, 2021 (Julien Blanc) > 10. Re: [Boost] [Describe] Summary Review Summary (Emil Dotchevski) > 11. Re: [Lambda2] Review starts Monday March 22, 2021 to March > 31, 2021 (Mathias Gaunard) > 12. Re: [Boost] [Lambda2] Review starts Monday March 22, 2021 to > March 31, 2021 (Mathias Gaunard) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Thu, 25 Mar 2021 14:54:17 +0100 > From: Andrzej Krzemienski <akrzemi1(a)gmail.com> > To: Boost mailing list <boost(a)lists.boost.org> > Cc: Peter Dimov <pdimov(a)gmail.com> > Subject: Re: [boost] [Boost] [Lambda2] Review starts Monday March 22, > 2021 to March 31, 2021 > Message-ID: > <CAOenAXhsJ1yCRRBYgJuPh8xws5MMVCks7p6GvfmBG+= > 28QDNPg(a)mail.gmail.com> > Content-Type: text/plain; charset="UTF-8" > > pon., 22 mar 2021 o 16:44 Peter Dimov via Boost <boost(a)lists.boost.org> > napisa?(a): > > > Edward Diener wrote: > > > My first reaction, after quickly looking at the submission, is what > does > > this > > > library offer that the original lambda library, which appears to have a > > much > > > larger amount of functionality than this lambda2 library, not offer ? > > Also there > > > is the Phoenix library, which also offers an even greater amount of > > function > > > object and lambda-like functionality, of which the review manager is > the > > main > > > author I believe. > > > > Purely from a user perspective, what this library offers is being a > > lightweight, > > single header dependency, and... > > > > > Is it basically so that the programmer can easily interface with > > > the std::bind/std::function classes with the lambda2 placeholders, > > whereas the > > > C++03 libraries don't have this possibility wit their placeholders ? > > > > ... indeed, a way to port boost::bind code that uses its operators to > > std::bind, > > something that comes up from time to time as projects are modernized. > > > > From a different perspective, another goal of the submission is to gather > > experience and provide a tested and widely available implementation for > an > > eventual proposal to add this functionality to the standard. (Better late > > than > > never.) > > > > My opinion so far is that there is not enough motivation to warrant the > addition of this library into Boost. > > First, the design goals, or the purpose, of the library is not clearly > defined. > > Is the goal that tandem std::bind + Boost.Lambda2 should be a replacement > over boost::bind and Boost.Lambda? If so, in the current form of the > library the goal will not be satisfied, because current Boost.Lambda offers > quite more things. Just look at the motivating examples of Boost.Lambda: > https://www.boost.org/doc/libs/1_75_0/doc/html/lambda/using_library.html > In particular, the usage of assignment or function constant(). > Boost.Lambda2 will not work as a drop-in replacement for Boost.Lambda. > > For a moment I thought that the goal is to have a cooler syntax for the > current standard arithmetic function objects, such as std::plus, > std::multiplies. But the advantage is dubious. You gain a few characters, > but you pay the cost of > * employing a different library > * messy error messages > * no debugger support > > The suggestion that we would enable constructs like > `std::bind(&Employee::name, e1) < std::bind(&Employee::name, e2)`also > doesn't seem like a good motivation. std::bind only works well when it is > used for binding arguments to functions. Overusing it for implementing > lambdas made sense in C++03, because there was no other way. Now with > generic lambdas it can only be considered a bad (or at least controversial) > practice. > > I am far from imposing my programming style on others. But promoting a > programming style like this through the inclusion into Boost seems too > much. My vision of Boost is that it should support certain programming > styles that are considered good, but not any programming style. > > Regarding the implementation, on the other hand, it is as elegant as a > library implementation could ever be. It is extremely short! (78 lines, > including whitespace, header guards, and copyright notice). > > Regards, > &rzej; > > > ------------------------------ > > Message: 2 > Date: Thu, 25 Mar 2021 15:06:02 +0000 > From: Niall Douglas <s_sourceforge(a)nedprod.com> > To: boost(a)lists.boost.org > Subject: Re: [boost] [release] 1.76.0 post-beta merges > Message-ID: <6efb04af-9f26-4d04-a187-8bc08369caf3(a)nedprod.com> > Content-Type: text/plain; charset=utf-8 > > On 16/03/2021 20:24, Marshall Clow via Boost wrote: > > The master branch is is now open for post-beta merges, but only as > described in the Post-Beta Merge Policy. > > See < > https://github.com/boostorg/boost/wiki/Releases%3A-Beta-Merge-Policy> > > I would like to fix https://github.com/ned14/outcome/issues/249 by > improving the logic at > > https://github.com/ned14/outcome/blob/develop/include/outcome/convert.hpp#L… > please. > > Niall > > > ------------------------------ > > Message: 3 > Date: Thu, 25 Mar 2021 17:24:15 +0200 > From: "Peter Dimov" <pdimov(a)gmail.com> > To: "'Andrzej Krzemienski'" <akrzemi1(a)gmail.com>, "'Boost mailing > list'" <boost(a)lists.boost.org> > Subject: Re: [boost] [Boost] [Lambda2] Review starts Monday March 22, > 2021 to March 31, 2021 > Message-ID: <131601d7218a$eb1033b0$c1309b10$(a)gmail.com> > Content-Type: text/plain; charset="utf-8" > > Andrzej Krzemienski wrote: > > First, the design goals, or the purpose, of the library is not clearly > defined. > > The goals of the library are > > - Give people the choice of using an abbreviated lambda syntax that is able > to express simple operations in fewer characters; > - Bring std::bind to parity with boost::bind feature-wise so that porting > is > easier; > - Prepare a proposal to extend the standard with these same additions by > gathering experience in Boost first. > > > Is the goal that tandem std::bind + Boost.Lambda2 should be a replacement > > over boost::bind and Boost.Lambda? If so, in the current form of the > library > > the goal will not be satisfied, because current Boost.Lambda offers > quite more > > things. > > This doesn't make it useless. When porting "operator-enhanced" boost::bind, > or Boost.Lambda, code, you need to go over all the uses and change them > into language lambdas. This is routine mechanical work that as a result is > highly error-prone and without good test coverage, mistakes can easily pass > review because of the repetitive nature of the diff. It's much better if > you > could port at least some of the uses without making changes beyond > replacing > boost:: with std::, and adding/changing the using directive. > > It's not necessary to be able to port _all_ uses without any changes; a > portion > is enough to reduce the error rate significantly. > > And if you're going to ask what's the point of porting from one Boost > library > to another, the difference is that it's much easier to "vendor" a single > short > header. > > > For a moment I thought that the goal is to have a cooler syntax for the > current > > standard arithmetic function objects, such as std::plus, > std::multiplies. But the > > advantage is dubious. You gain a few characters, but you pay the cost of > > * employing a different library > > * messy error messages > > * no debugger support > > This could be true, but it has nothing to do with the library lacking > clarity of > purpose. > > > The suggestion that we would enable constructs like > > `std::bind(&Employee::name, e1) < std::bind(&Employee::name, e2)`also > > doesn't seem like a good motivation. > > As explained, this is only an issue when porting boost::bind code using > these constructs. You obviously aren't going to use this in new code > because > the equivalent language lambda is shorter (not by much) and clearer. > > > > ------------------------------ > > Message: 4 > Date: Thu, 25 Mar 2021 08:45:22 -0700 > From: Marshall Clow <mclow.lists(a)gmail.com> > To: Boost Developers List <boost(a)lists.boost.org> > Subject: Re: [boost] [release] 1.76.0 post-beta merges > Message-ID: <0EAF569D-A080-4217-BC77-D7CE4057EC0A(a)gmail.com> > Content-Type: text/plain; charset=utf-8 > > On Mar 25, 2021, at 8:06 AM, Niall Douglas via Boost < > boost(a)lists.boost.org> wrote: > > > > On 16/03/2021 20:24, Marshall Clow via Boost wrote: > >> The master branch is is now open for post-beta merges, but only as > described in the Post-Beta Merge Policy. > >> See < > https://github.com/boostorg/boost/wiki/Releases%3A-Beta-Merge-Policy> > > > > I would like to fix https://github.com/ned14/outcome/issues/249 by > > improving the logic at > > > https://github.com/ned14/outcome/blob/develop/include/outcome/convert.hpp#L… > > please. > > Do you have a commit that fixes this? > > ? Marshall > > > > > ------------------------------ > > Message: 5 > Date: Thu, 25 Mar 2021 16:04:17 +0000 > From: Niall Douglas <s_sourceforge(a)nedprod.com> > To: Boost Developers List <boost(a)lists.boost.org> > Subject: Re: [boost] [release] 1.76.0 post-beta merges > Message-ID: <2dc9222a-592a-6b85-c76b-d62ef55611b3(a)nedprod.com> > Content-Type: text/plain; charset=utf-8 > > On 25/03/2021 15:45, Marshall Clow wrote: > > On Mar 25, 2021, at 8:06 AM, Niall Douglas via Boost < > boost(a)lists.boost.org> wrote: > >> > >> On 16/03/2021 20:24, Marshall Clow via Boost wrote: > >>> The master branch is is now open for post-beta merges, but only as > described in the Post-Beta Merge Policy. > >>> See < > https://github.com/boostorg/boost/wiki/Releases%3A-Beta-Merge-Policy> > >> > >> I would like to fix https://github.com/ned14/outcome/issues/249 by > >> improving the logic at > >> > https://github.com/ned14/outcome/blob/develop/include/outcome/convert.hpp#L… > >> please. > > > > Do you have a commit that fixes this? > > The change is trivial. Current: > > ```c++ > #if !defined(_MSC_VER) && !defined(__clang__) && (__GNUC__ < 9 || > __cpp_concepts < 201907L) > #define OUTCOME_GCC6_CONCEPT_BOOL bool > #else > #define OUTCOME_GCC6_CONCEPT_BOOL > #endif > ``` > > To be replaced with: > > ```c++ > #if (defined(_MSC_VER) || defined(__clang__) || (defined(__GNUC__) && > __cpp_concepts >= 201707) || OUTCOME_FORCE_STD_CXX_CONCEPTS) && > !OUTCOME_FORCE_LEGACY_GCC_CXX_CONCEPTS > #define OUTCOME_GCC6_CONCEPT_BOOL > #else > #define OUTCOME_GCC6_CONCEPT_BOOL bool > #endif > ``` > > To explain, GCC expects bool with concept, or not, in varying > configuration combinations which have evolved over GCC versions, > including apparently point releases, which is deeply unhelpful. This has > led to repeated bug reports for not just Outcome, but also for ASIO and > many other C++ projects. > > If this above fix doesn't permanently shut this constant source of bug > reports, I'll be permanently disabling legacy GCC concepts support in > Outcome. I couldn't be arsed with supporting how unpredictably broken > GCC is with this. > > Niall > > > ------------------------------ > > Message: 6 > Date: Thu, 25 Mar 2021 12:12:03 -0400 > From: Glen Fernandes <glen.fernandes(a)gmail.com> > To: boost(a)lists.boost.org > Subject: Re: [boost] [release] 1.76.0 post-beta merges > Message-ID: > <CAHVPgznFdSVYJ9gR8LzP7qQV7w5+fcjBvKq95ReUKkFR-ct= > Qg(a)mail.gmail.com> > Content-Type: text/plain; charset="UTF-8" > > On Thu, Mar 25, 2021 at 12:04 PM Niall Douglas via Boost > <boost(a)lists.boost.org> wrote: > > > > On 25/03/2021 15:45, Marshall Clow wrote: > > > On Mar 25, 2021, at 8:06 AM, Niall Douglas via Boost < > boost(a)lists.boost.org> wrote: > > >> > > >> I would like to fix https://github.com/ned14/outcome/issues/249 by > > >> improving the logic at > > >> > https://github.com/ned14/outcome/blob/develop/include/outcome/convert.hpp#L… > > >> please. > > > > > > Do you have a commit that fixes this? > > > > The change is trivial. Current: > > If you're asking for permission to merge to master now, you should > have a commit on outcome's develop branch that we can look at. You are > free to commit to develop at any time. Only master is locked. > > Glen > > > ------------------------------ > > Message: 7 > Date: Thu, 25 Mar 2021 19:10:33 +0100 > From: Julien Blanc <julien.blanc(a)tgcm.eu> > To: boost(a)lists.boost.org > Subject: Re: [boost] [Lambda2] Review starts Monday March 22, 2021 to > March 31, 2021 > Message-ID: <2773cbf43ec651fdf2b3a3262c8476d814047eb0.camel(a)tgcm.eu> > Content-Type: text/plain; charset="UTF-8" > > Le lundi 22 mars 2021 ? 10:35 +0800, Joel de Guzman via Boost a ?crit?: > > The Boost formal review of the Lambda2, authored by Peter Dimov, > > starts Monday, March 22, 2021 to March 31, 2021 (inclusive). > > Here's my small review of the lambda 2 library. > > TLDR: ACCEPT > > > ?? - What is your evaluation of the design? > > ?? - What is your evaluation of the implementation? > > The library is a really small piece of code, like other reviewers > already noticed. During my tests, i came across two things that could > be improved: > * the internal macro BOOST_LAMBDA2_UNARY_LAMBDA and > BOOST_LAMBDA2_BINARY_LAMBDA #undefed at the end of the file. While i > undestand that it is an internal macro, it could be exposed to the user > to allow implementation for other operators > * that macro hardcode the std prefix, it could be part of its call, ie: > > BOOST_LAMBDA2_BINARY_LAMBDA(+, std::plus) // instead of > BOOST_LAMBDA2_BINARY_LAMBDA(+, plus) > > This would allow the user of the library to get the building blocks to > customize other operators to its needs (I have implemented unary > operator* easily that way). > > > ?? - What is your evaluation of the documentation? > > The documentation is really good at telling what the library does, is > clean, nice looking. > > > ?? - What is your evaluation of the potential usefulness of the > > library? > > At first glance, i was thinking that this was the kind of library that > i would never use. I find the count_if examples in the documentation > not really convincing. > > Then, it happened that i made some experiments with c++20 ranges. And i > find that, in this context, shortening the lambdas gives a real benefit > to the code. It basically started from the need to feed a function that > was needing a list of non owner references to T from a > vector<unique_ptr<T>>. As I was not satisfied with the solution, I > checked whether c++20 ranges could provide an elegant solution to this. > Something like > > f(std::views::transform(vec, deref)); > > implementing deref is easy. Then, out of curiosity, i checked if i > could use Peter's library to be able to write something like: > > f(std::views::transform(vec, *_1)); > > I actually find that this way of writing is more natural than the > former. > > So, i wrote : > > namespace std // BAD, don't do that > { > template<typename T = void> > struct deref > { > decltype(auto) operator()(T& v) { return *v; } > }; > template<> > struct deref<void> > { > template<typename T> > decltype(auto) operator()(T& v) { return *v; } > }; > } > > BOOST_LAMBDA2_UNARY_LAMBDA(*, deref); > > modified Peter's library to remove the #undef, and voila, it just > works. > > I see a lot of potential for the short writing form for lambdas, in > conjunction with the ranges library. I find convenient to write: > > f(std::views::transform(vec, _1 + 1)) // convert from 0-based to 1- > based index > > > ?? - Did you try to use the library? With which compiler(s)? Did you > > ???? have any problems? > > No specific issue encountered, with gcc-10. Error messages are a bit > cryptic. > > > ?? - How much effort did you put into your evaluation? A glance? A > > quick > > ???? reading? In-depth study? > > A few hours playing with the library. > > > ?? - Are you knowledgeable about the problem domain? > > Not at all. > > My feeling is the following. At first glance, i was wondering what was > the use case the library addressed. After playing a bit with it, i'm > now convinced that people will want to use it, and, like me, will > probably want to expand it to fit their need. I was not suspecting that > it was possible to write code that way. I suspect most developers are > not either. Now that it is known it's possible, people will come up > with their own, probably inferior, solution. Having such a feature in > boost would at least provide everyone with a correct implementation of > it. Because people will want to write code like this, and i believe, > especially with ranges. > > Thanks to Peter for writing this library, and proposing it to boost. > Reviewing it has been very interesting and instructive. > > Regards, > > Julien > > > > ------------------------------ > > Message: 8 > Date: Fri, 26 Mar 2021 05:54:36 +0100 > From: Andrzej Krzemienski <akrzemi1(a)gmail.com> > To: Boost mailing list <boost(a)lists.boost.org> > Subject: Re: [boost] [Lambda2] Review starts Monday March 22, 2021 to > March 31, 2021 > Message-ID: > <CAOenAXgEDx= > kmKY5gVdST-oAeipoa2oG2s5j_y0brxs34r7ojw(a)mail.gmail.com> > Content-Type: text/plain; charset="UTF-8" > > czw., 25 mar 2021 o 19:11 Julien Blanc via Boost <boost(a)lists.boost.org> > napisa?(a): > > > Le lundi 22 mars 2021 ? 10:35 +0800, Joel de Guzman via Boost a ?crit : > > > The Boost formal review of the Lambda2, authored by Peter Dimov, > > > starts Monday, March 22, 2021 to March 31, 2021 (inclusive). > > > > Here's my small review of the lambda 2 library. > > > > TLDR: ACCEPT > > > > > - What is your evaluation of the design? > > > - What is your evaluation of the implementation? > > > > The library is a really small piece of code, like other reviewers > > already noticed. During my tests, i came across two things that could > > be improved: > > * the internal macro BOOST_LAMBDA2_UNARY_LAMBDA and > > BOOST_LAMBDA2_BINARY_LAMBDA #undefed at the end of the file. While i > > undestand that it is an internal macro, it could be exposed to the user > > to allow implementation for other operators > > * that macro hardcode the std prefix, it could be part of its call, ie: > > > > BOOST_LAMBDA2_BINARY_LAMBDA(+, std::plus) // instead of > > BOOST_LAMBDA2_BINARY_LAMBDA(+, plus) > > > > This would allow the user of the library to get the building blocks to > > customize other operators to its needs (I have implemented unary > > operator* easily that way). > > > > Is it not just that the library is missing some operators? If Boost.Lambda2 > overloaded all overloadable operators there would be no point in users > doing it. > > > > > - What is your evaluation of the documentation? > > > > The documentation is really good at telling what the library does, is > > clean, nice looking. > > > > > - What is your evaluation of the potential usefulness of the > > > library? > > > > At first glance, i was thinking that this was the kind of library that > > i would never use. I find the count_if examples in the documentation > > not really convincing. > > > > Then, it happened that i made some experiments with c++20 ranges. And i > > find that, in this context, shortening the lambdas gives a real benefit > > to the code. It basically started from the need to feed a function that > > was needing a list of non owner references to T from a > > vector<unique_ptr<T>>. As I was not satisfied with the solution, I > > checked whether c++20 ranges could provide an elegant solution to this. > > Something like > > > > f(std::views::transform(vec, deref)); > > > > implementing deref is easy. Then, out of curiosity, i checked if i > > could use Peter's library to be able to write something like: > > > > f(std::views::transform(vec, *_1)); > > > > I actually find that this way of writing is more natural than the > > former. > > > > This is an interesting observation. In my experience, storing collections > of ints is a rare case in production code (it is frequent in tests, > tutorials, books, presentations), maybe this is why arithmetic operators do > not appear as something practical. However pointers (including smart ones) > to user-defined types is something that I see a lot. The following als > looks as something I would see often in the code: > > assert(std::ranges::all_of(records, _1 != nullptr)); > > Regards, > &rzej; > > > > So, i wrote : > > > > namespace std // BAD, don't do that > > { > > template<typename T = void> > > struct deref > > { > > decltype(auto) operator()(T& v) { return *v; } > > }; > > template<> > > struct deref<void> > > { > > template<typename T> > > decltype(auto) operator()(T& v) { return *v; } > > }; > > } > > > > BOOST_LAMBDA2_UNARY_LAMBDA(*, deref); > > > > modified Peter's library to remove the #undef, and voila, it just > > works. > > > > I see a lot of potential for the short writing form for lambdas, in > > conjunction with the ranges library. I find convenient to write: > > > > f(std::views::transform(vec, _1 + 1)) // convert from 0-based to 1- > > based index > > > > > - Did you try to use the library? With which compiler(s)? Did you > > > have any problems? > > > > No specific issue encountered, with gcc-10. Error messages are a bit > > cryptic. > > > > > - How much effort did you put into your evaluation? A glance? A > > > quick > > > reading? In-depth study? > > > > A few hours playing with the library. > > > > > - Are you knowledgeable about the problem domain? > > > > Not at all. > > > > My feeling is the following. At first glance, i was wondering what was > > the use case the library addressed. After playing a bit with it, i'm > > now convinced that people will want to use it, and, like me, will > > probably want to expand it to fit their need. I was not suspecting that > > it was possible to write code that way. I suspect most developers are > > not either. Now that it is known it's possible, people will come up > > with their own, probably inferior, solution. Having such a feature in > > boost would at least provide everyone with a correct implementation of > > it. Because people will want to write code like this, and i believe, > > especially with ranges. > > > > Thanks to Peter for writing this library, and proposing it to boost. > > Reviewing it has been very interesting and instructive. > > > > Regards, > > > > Julien > > > > > > _______________________________________________ > > Unsubscribe & other changes: > > http://lists.boost.org/mailman/listinfo.cgi/boost > > > > > ------------------------------ > > Message: 9 > Date: Fri, 26 Mar 2021 07:44:43 +0100 > From: Julien Blanc <julien.blanc(a)tgcm.eu> > To: boost(a)lists.boost.org > Subject: Re: [boost] [Lambda2] Review starts Monday March 22, 2021 to > March 31, 2021 > Message-ID: <54d581dd2987773250b0f822393ea819a03297bc.camel(a)tgcm.eu> > Content-Type: text/plain; charset="UTF-8" > > Le vendredi 26 mars 2021 ? 05:54 +0100, Andrzej Krzemienski via Boost a > ?crit?: > > > This would allow the user of the library to get the building blocks > > > to > > > customize other operators to its needs (I have implemented unary > > > operator* easily that way). > > > > > > > Is it not just that the library is missing some operators? If > > Boost.Lambda2 > > overloaded all overloadable operators there would be no point in > > users > > doing it. > > Agreed. But I don't have a strong opinion on whether the library should > implement everything, or just be more open to user extensions. > > > The following als looks as something I would see often in the code: > > > > assert(std::ranges::all_of(records, _1 != nullptr)); > > Definitely. That's the kind of motivating example that i think should > appear in the documentation. > > Regards, > > Julien > > > > ------------------------------ > > Message: 10 > Date: Fri, 26 Mar 2021 00:23:56 -0700 > From: Emil Dotchevski <emildotchevski(a)gmail.com> > To: Boost <boost(a)lists.boost.org> > Subject: Re: [boost] [Boost] [Describe] Summary Review Summary > Message-ID: > < > CAN5fK5H0Cr5OmaX2ryTjRcboLu8xqiv3eKuYdCaft6EZXKFh9Q(a)mail.gmail.com> > Content-Type: text/plain; charset="UTF-8" > > On Wed, Mar 24, 2021 at 7:35 AM Jeff Garland via Boost < > boost(a)lists.boost.org> wrote: > > > The committee seems to be concerned more with internal and external > > > politics than with serving the community. If that wasn't true there > would > > > be ZERO library additions that haven't been battle hardened by being > > > deployed and established themselves as the defacto standard already. > > > > Unlike the boost review where there's 'a decider', the committee uses > > consensus. It's a much higher bar, as frankly, it should be. > > A "much higher bar" can prevent a good library from being accepted or > prevent a bad library from being rejected. That is, consensus cuts both > ways. > > > As for battle hardened, sometimes it's not quite so simple as sometimes > > language changes are needed or vendor support is needed. Every proposal > > gets vetted for usage experience and it's clear that without experience > > it's unlikely to go forward. Is the process perfect -- no. Will it make > > everyone, even the members happy -- no. Can it be improved -- surely -- > > but like many things in life it's not as simple as we'd like. > > We can talk about the case when language changes are needed but let's focus > on libraries. > > > > The only thing they should be doing is rubber-stamping libraries that > are > > > already the standard for doing something. > > > > And if we 'just did that', things like generic programming wouldn't exist > > in c++. If the 'Roque Wave' container design was adopted in 1998 the > world > > would be very different now. > > There was no GitHub in 1998. Today it feels like some authors treat the > standard library as a vehicle for making their library available everywhere > in hopes it'll get adopted. All I'm saying is that adoption should come > before standardization. Git pull requests are better than Subversion > commits. > > > And if you want one of those 'battle hardened' libraries > > adopted, that's fine > > You see, I think it is problematic to "want" to standardize a library. IMO > the standardization process should be dull and boring, rather than driven > by exciting innovation. > > > ------------------------------ > > Message: 11 > Date: Fri, 26 Mar 2021 10:11:43 +0000 > From: Mathias Gaunard <mathias.gaunard(a)ens-lyon.org> > To: Boost mailing list <boost(a)lists.boost.org> > Subject: Re: [boost] [Lambda2] Review starts Monday March 22, 2021 to > March 31, 2021 > Message-ID: > <CALnjya9TV+n=N-0_8zWsu_+zGTAW= > xezCsQ4C3vnBU6wZ6LkNw(a)mail.gmail.com> > Content-Type: text/plain; charset="UTF-8" > > On Fri, 26 Mar 2021 at 04:54, Andrzej Krzemienski via Boost > <boost(a)lists.boost.org> wrote: > > > > This is an interesting observation. In my experience, storing collections > > of ints is a rare case in production code (it is frequent in tests, > > tutorials, books, presentations), maybe this is why arithmetic operators > do > > not appear as something practical. > > They do appear frequently if you use column-oriented data structures, > which are generally better at dealing with large collections of data. > > > ------------------------------ > > Message: 12 > Date: Fri, 26 Mar 2021 10:16:17 +0000 > From: Mathias Gaunard <mathias.gaunard(a)ens-lyon.org> > To: Boost mailing list <boost(a)lists.boost.org> > Subject: Re: [boost] [Boost] [Lambda2] Review starts Monday March 22, > 2021 to March 31, 2021 > Message-ID: > < > CALnjya8bbeFs1d4q2pSbr8azU3aELbXVDtyCDtj+xioUDdkaEw(a)mail.gmail.com> > Content-Type: text/plain; charset="UTF-8" > > On Mon, 22 Mar 2021 at 02:35, Joel de Guzman via Boost > <boost(a)lists.boost.org> wrote: > > > > The Boost formal review of the Lambda2, authored by Peter Dimov, > > starts Monday, March 22, 2021 to March 31, 2021 (inclusive). > > > > Documentation: https://pdimov.github.io/lambda2/doc/html/lambda2.html > > Source: https://github.com/pdimov/lambda2/ > > > > Lambda2 is a simple, but functional, C++14 lambda library. It takes > advantage > > of the fact that the standard <functional> header already provides > placeholders > > _1, _2, _3, and so on, for use with std::bind, and function objects such > > as std::plus, std::greater, std::logical_not, and std::bit_xor, > corresponding to > > arithmetic, relational, logical and bitwise operators. > > > > Please provide in your review information you think is valuable to > > understand your choice to ACCEPT or REJECT including Lambda2 as a > > Boost library. Please be explicit about your decision (ACCEPT or REJECT). > > > > Some other questions you might want to consider answering: > > > > - What is your evaluation of the design? > > - What is your evaluation of the implementation? > > - What is your evaluation of the documentation? > > It is not clear from the documentation what the capture behaviour of > terminals is. > I assume it's capturing rvalues by value and lvalues by reference? > > What about the expression tree itself, is it fully by value, and > therefore safely copyable? > Boost.Proto for example by default is binding everything by reference, > meaning that you couldn't even store the expression in a variable. Is > it avoiding this issue? > > > ------------------------------ > > Subject: Digest Footer > > _______________________________________________ > Unsubscribe & other changes: > http://lists.boost.org/mailman/listinfo.cgi/boost > > > ------------------------------ > > End of Boost Digest, Vol 6566, Issue 1 > ************************************** >

1 0

[GSoC] Boost.Real: Introduction and Guidence
by Suraj Nehra 28 Mar '21

28 Mar '21

Hi, I am Suraj Nehra, a pre-final year student at the National Institute of Technology (NIT), Warangal, India. This mail is to introduce myself to the boost community. Boost.Real is not added to boost project ideas page yet but I was discussing ideas with Vikram(vikram2000b(a)gmail.com) and also made several contributions to the library. I wish to work on this library in this GSoC and will start drafting the proposal. I received the competency task from Vikram and will start working on those. I was informed of the following potential ideas by him: 1. Library comparison and benchmarking with other similar libraries. 2. DAG internal representation 3. Propose and implement optimizations for trigonometric functions. I wish to work on ideas 1 and 3. I will start making the proposal for these ideas and share the draft with you. It will be a pleasure to hear any suggestions and guidance from you. Thanks & Regards Suraj Nehra

1 0

(no subject)
by Suraj Nehra 28 Mar '21

28 Mar '21

Hi, I am Suraj Nehra, a pre-final year student at the National Institute of Technology (NIT), Warangal, India. This mail is to introduce myself to the boost community. Boost.Real is not added to boost project ideas page yet but I was discussing ideas with Vikram(vikram2000b(a)gmail.com) and also made several contributions to the library. I wish to work on this library in this GSoC and will start drafting the proposal. I received the competency task from Vikram and will start working on those. I was informed of the following potential ideas by him: 1. Library comparison and benchmarking with other similar libraries. 2. DAG internal representation 3. Propose and implement optimizations for trigonometric functions. I wish to work on ideas 1 and 3. I will start making the proposal for these ideas and share the draft with you. It will be a pleasure to hear any suggestions and guidance from you. Thanks & Regards Suraj Nehra

1 0

To contact project's mentor for GSoC21
by prince raj 26 Mar '21

26 Mar '21

Hello, My self Anish Kumar Singh and I want to participate to in boost organisation. But I have no idea how to contact mentor for project discussion and my ideas with him. So please help me contacting to mentor so that I can make my proposal good to summit. Thankyou...

3 2

[Boost] [Describe] Summary Review Summary
by Richard Hodges 26 Mar '21

26 Mar '21

Boost Describe Review Summary Boost Describe was submitted by Peter Dimov. The review period lasted from 1st March 2021 until 10th March 2021, inclusive. Overall Verdict Boost.Describe has been accepted into Boost. Detailed Results In all, 13 people submitted reviews. Of these 13, 11 reviews were an unconditional ACCEPT. The remaining two reviews were marked CONDITIONAL ACCEPT. This seems to be common practice, as committing firmly to accept or reject can seem like a bold position either way. However the Boost review process has no provision for attaching conditions to library acceptance. The verdict must be either that the library is sufficiently well written and documented, as well as providing sufficient utility, to be included in the Boost offering, or it is not. Conditional Acceptances In this review I counted the two remaining conditional acceptances as ACCEPT, and decided to pass the conditions as comments/suggestions on to the author for consideration, as well as enumerate them in this report in the hope that further study/debate is stimulated. Libraries evolve over time, and the comments will no doubt be useful to Peter when making future decisions about Boost.Describe. I will deal with the conditions mentioned by Julain Blanc first. Julian’s concerns centered around the fact that the bitfield supplied to the describe_members macro is not additive. I will quote his example here. Given the following code: struct C { int a; std::string b; double c; void f(float a, int b) { } void g() { } static void s() {} private: int p_; void h_(std::string const& s) {} BOOST_DESCRIBE_CLASS(C, (), (a, b, c, f, g, s), (), (p_, h_)) }; I would expect the following: static_assert(mp_size<describe_members<C, mod_public>>::value == 6); static_assert(mp_size<describe_members<C, mod_private>>::value == 2); That's not the case. Instead, the results are resp 3 and 1. By default, only data members are returned, not member functions. So, let's try another one. I want all my member functions: static_assert(mp_size<describe_members<C, mod_function | mod_public | mod_protected | mod_private >>::value == 4) --> fails. By default, it only returns non-static functions. So, let's try to include static function as well: static_assert(mp_size<describe_members<C, mod_static | mod_function | mod_public | mod_protected | mod_private >>::value == 4) That also fails. The result is one, now i only get the static functions. It looks that there's a mix of apples and orange in this enum. Some values acts as they will include more data in the results, some on the contrary will filter, and some will change completely the type of the members enumerated. This concern resonates with me, as I raised a similar (but less well written) query with Peter in the same area. Barrett Adair was the author of the second conditional accept. His reasoning was along the same lines as Julian’s, quoted: I don't like that I need to call describe_members multiple times to get static, non-static, data, and functions. I would appreciate the addition of mod_data and mod_nonstatic to keep the flags consistent. This is my only acceptance condition. Peter took time to respond to this concern: The reason the static/nonstatic and data/function members are returned separately is that the type of `pointer` changes. For nonstatic data, it's M T::*. For static data, it's M*. For nonstatic function, it's R (T::*)(A...). For static function, it's R (*)(A...). Since one typically does things with `pointer` in the loop over members, it's rarely the case that you want all of these at once, because the syntactic form of the code manipulating them changes. So I've found it in practice more convenient to separate them by default. It is fair to say that in less recent variants of C++, iterating over different pointer types would be problematic, although arguably less so with later variants of C++ if some accessor function template overloads or CPOs were made available in the library. The decision on whether this should be explored rests with Peter. Documentation and Examples Reviewers almost universally commented on the quality and completeness of the documentation. Particular attention was drawn to the numerous examples that clearly represent common real-world use cases. Features Requested Rainer Deyke requested the ability to annotate members with further attributes. Peter responded that he would look into whether this was possible while retaining compatibility with likely future standards adoptions of reflection, which is a design goal of the library. Maximilian Riemensberger wondered whether it would be possible to support reference members and overloaded functions. Peter’s response was that alas, no. The language itself is a limiting factor there. Maximilian also requested the ability to annotate enums with associated data. For example, representing an enum value as text when the text cannot be reasonably computed from the value’s symbolic name. Peter agreed to consider this further. Maximilian also touched on the single-pass iteration issue, which brings the number of observers who feel there is good grounds for future evolution to four. Overall Usefulness of the Library The reviewers were unanimous in calling out the need for this kind of library. From reading the reviews it is apparent that a great deal of developer effort is duplicated in writing custom reflection mechanisms. It struck me that (any kind of) language-level compile-time reflection would be welcomed with open arms by the developer community. Perhaps we can hope that the acceptance of Describe into Boost and its subsequent use can inform and encourage the C++ language group to bring something to the community sooner than later. Please join me in extending gratitude to Peter, who has taken time and painstaking effort to present us with such a useful, succinct and well documented library. Please also join me in thanking the reviewers, who can be sure that the detailed analysis included has been read and in for the most part, already elicited a response/bug-fix from Peter. Sincerely, Richard Hodges -- Richard Hodges hodges.r(a)gmail.com office: +442032898513 mobile: +376380212

12 31

C++17 and "Alice in Wonderland"
by Edward Diener 24 Mar '21

24 Mar '21

I apologize for this non-Boost related post, but I ran into what I thought was a C++17 bug in clang ( also in vc++14.2 C++17 ), whose explanation to me of why it is not a bug really sounds like the non-logic of "Alice in Wonderland". I am not putting down the person who explains to me why it is not a bug in any way, as I know he is a C++ expert, but if this is really C++17 something must be wrong with my admittedly limited understanding of C++ and where it is going. My bug report is at https://bugs.llvm.org/show_bug.cgi?id=49684 and the explanation given there just eludes me as to what C++17 is doing, as my further comments makes apparent. Does anyone actually understand how this can possibly be ? How does C++17 apparently deduce a template argument different from what the actual type is and than declare therefore a mismatch ? This is really something from another world. My apologies for bringing this up in Boost, as it is purely a C++ issue, but my original problem comes from something I have been working on in the hopes it might eventually be a Boost library, so I decided to see if any of the expert Boost contributors might know what is going on in C++17. I realize that if everyone did as I have done here the mailing list would be a mass of irrelevant posts not Boost related.

9 11

Boost 1.76 beta - linking error when including Boost
by Luigi Ballabio 24 Mar '21

24 Mar '21

Hello, I'm afraid I don't have a minimal example yet, but I thought I'd give you a heads-up in case it rings a bell. I've been trying the Boost 1.76 beta to build a library I'm maintaining. The library builds, but when I link it to an executable I'm getting an "undefined reference to `bool boost::math::isnan<long double>(long double)". Everything works with 1.75 and earlier. My code is not using boost::math::isnan directly, so I'm guessing some other included boost component is forward-declaring it or doing something similar? The linking error disappears if I include <boost/math/special_functions/fpclassify.hpp> in a config file that is included by every file in the library. Today I'll try to pinpoint the problem by removing it there and including it before specific boost headers in the source files, but as I said, I'm posting this in case someone already has an idea about the underlying issue. Thanks, Luigi

3 4

Any Interest in a port of ZLib to C++?
by Vinnie Falco 24 Mar '21

24 Mar '21

Beast currently has its own port of ZLib to C++: <https://github.com/boostorg/beast/tree/develop/include/boost/beast/zlib> Is there any interest in having this proposed as its own separate Boost library (with a separate review, which has nothing to do with Beast)? The differences would be as follows: * Ported to use C++11 idioms * Same header-only / compiled source model as Boost.JSON * Better documentation and clear API * Improved tests Programs which use this C++ port of ZLib would get their zlib dependency from Boost instead of the official zlib distribution. And they can integrate it into their projects the same way that Boost libraries are integrated. Or they can include <boost/zlib/src.hpp> in any one translation unit (like JSON). The motivation for this is twofold: * Provide an easier way for users to access ZLib's functionality * To use this in some new libraries that I'm going to propose -- Regards, Vinnie Follow me on GitHub: https://github.com/vinniefalco

11 14

[Boost.JSON] Security Review
by Vinnie Falco 23 Mar '21

23 Mar '21

As part of our commitment to producing the very finest C++ libraries that application developers can trust, the C++ Alliance has commissioned Bishop Fox to perform a security audit of the Boost.JSON library. The report is linked here: <https://cppalliance.org/pdf/C%20Plus%20Plus%20Alliance%20-%20Boost%20JSON%2…> This will report will be published starting in Boost 1.76.0 -- Regards, Vinnie Follow me on GitHub: https://github.com/vinniefalco

1 0

boost library incubator planning shutdown
by Robert Ramey 22 Mar '21

22 Mar '21

I had high hopes for the boost library incubator when I made it. But I think it's pretty clear that those hopes haven't been realized. Maintaining and Enhancing this website required more effort than I had anticipated so it hasn't evolved. I do notice that people do use it from time to time (a couple hundred page hits/day), so it's not totally dead. But it would either have to go forward or be shut down. If someone wanted to take it over that would be fine. But I don't expect anyone to come forward so I'll be shutting it down probably in the next 30 days or so. Robert Ramey

1 0

Mentor application for Boost.Real
by Vikram Chundawat 21 Mar '21

21 Mar '21

Hello everyone, I am Vikram Singh Chundawat, I worked on Boost.Real previous GSoC and I am actively working on the library since. Now, one of the potential mentors Damian Vicino is not mentoring this year, I wish to mentor this project in GSoC 2021 with Laouen Belloli. We have some potential candidates who are working on the library and also some good ideas for the library. The aim last year was to bring Boost.Real to review ready state and some work is still remaining to make it review ready, we found some bugs in the review. Now, we are working on optimizations, bug fixes, and benchmarking. I went through the guidelines of Google and wish to know the procedure for mentor application. Thank You Regards Vikram Singh Chundawat

2 1

Proposing a library to include in Boost
by Mohit Saini 20 Mar '21

20 Mar '21

Hi, This is Mohit Saini. I developed a lazy_map library, whose interface is similar to std::unordered_map but lazy_map is O(1) copiable. Other operations like Deletion, Lookup, Insertion etc. continue to cost O(1).. which also implies that lazy_map is not a simple cow_wrapper<std::unordered_map> .. lazy_map is way more clever than that. Learn more at : https://github.com/tinytrashbin/lazy_map Specially, checkout the section which explains the "Fragment" tree. Lazy_map is heavily used in our codebase for taking snapshot of a very large state ( of size ~ 5 GBs), enabling "fork" of a snapshot in O(1) time for further modification in the forked snapshot, allowing a large number of threads to operate on different snapshots of very large size, concurrently without interfering with each other where each of the thread is even "writing" to their snapshot. I believe such a utility will be very helpful for others too. I'm looking for boost-maintainers who can review and suggest what all I need to do so that lazy_map can be accepted in Boost. Thanks -- Mohit Saini

1 0

Re: [boost] Feedback on GSoC'21 project proposal
by krushnalpatel11＠gmail.com 20 Mar '21

20 Mar '21

I have updated the proposal with the changes you proposed. Please check if all things are updated as per your feedback. https://docs.google.com/document/d/1Bvno6ifHjo8EdMRuzFqCk9AEB5IgAxf2ag4xdc4… Krushnal http://krushnal.me/ _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost </quote> Quoted from: http://boost.2283326.n4.nabble.com/Feedback-on-GSoC-21-project-proposal-tp4… _____________________________________ Sent from http://boost.2283326.n4.nabble.com

1 0

Re: [boost] Boost website changes and .'cxxstd'
by Donovan Dikaio 20 Mar '21

20 Mar '21

I can look into it. But needs to make the requirements clear. So, the task is to show *C++ standard minimum level: C++nn* for Standard attribute for each lib in this page: C++ standard minimum level: C++nn ? And we could replace nn with the actual number by checking the *cxxstd* key in a library's meta info json file. Please let me know if I got it right. On Fri, Dec 25, 2020 at 10:00 AM Louis Tatta <louis(a)cppalliance.org> wrote: > > > ---------- Forwarded message --------- > From: Edward Diener via Boost <boost(a)lists.boost.org> > Date: Wed, Dec 23, 2020 at 7:39 PM > Subject: [boost] Boost website changes and .'cxxstd' > To: <boost(a)lists.boost.org> > CC: Edward Diener <eldiener(a)tropicsoft.com> > > > Even though I have worked a little with PHP in the past I do not have > the talent to make the change to the website which would incorporate the > addition of the meta information json field 'cxxstd' to the Boost > documentation web page for each library. The idea is that if 'cxxstd' is > set to a value the documentation for that library would also show: > > C++ standard minimum level: C++nn > > where nn would be 11, 14, 17, or 20 depending on the value of 'cxxstd'. > Alternatively if there is no 'cxxstd' entry for a library or if the > value of 'cxxstd' is '03', we could either specify 'nn' as '03' or leave > off the line stating the 'C++ standard minimum level completely. > > On the face of it this should be doable in the website code but > evidently Daniel James is the only one who really understands how this > works in the code and he is no longer active in Boost. So if someone > else who understands the website code and PHP could do this it would be > appreciated, since I think it will be valuable telling end-users whether > a Boost library is usable at the C++ compiler level they are using. > > > _______________________________________________ > Unsubscribe & other changes: > http://lists.boost.org/mailman/listinfo.cgi/boost >

8 43

Providing a link to GitHub commit from documentation
by pbristow＠hetp.u-net.com 19 Mar '21

19 Mar '21

I've been considering adding commit hash info to some documentation made using the Quickbook/Boostbook/Docbook/b2/bjam toolchain Using git command line git log or ls-remote I can show the necessary hex digit string: commit 5609fa86e37e1b0eae6466065ba6c8eb3ac0ab2f (HEAD -> refactor1) (It would be useful to have the local commit (rather than remote) so that the generated documentation including this has can be pushed up to remote). Paul@hetpD MINGW64 /i/boost/libs/quan/doc (refactor1) $ git log -n1 HEAD > commit.txt That contains commit 5609fa86e37e1b0eae6466065ba6c8eb3ac0ab2f Author: pabristow <pbristow(a)hetp.u-net.com> Date: Fri Mar 19 15:46:45 2021 +0000 Generated super new version. So this gets this info into a file, but I have yet to see how to get this into the Quickbook or ? during the b2 build. I note that the Boost documentation headers provide this information in the form a link like displayed as d57d645009 with contents https://github.com/boostorg/boost/commit/d57d6450098300343c6fe3a22129791524… but I don't know how this works. Has anyone done anything like this? Suggestions most welcome. Paul

4 4

Feedback on GSoC'21 project proposal
by Krushnal Patel 19 Mar '21

19 Mar '21

Hi, I am applying for the project Boost.XML. I have completed the competency test and the next step being proposal feedback from mentors, I have made a draft proposal. https://docs.google.com/document/d/1Bvno6ifHjo8EdMRuzFqCk9AEB5IgAxf2ag4xdc4… As this is a new library, I have not been able to add much in the 'Project Proposal' details except the bare minimum details. Mentors please have a look at it and let me know what you think. Should I make additions, remove or edit some things? -- Awaiting your feedback, Krushnal Patel http://krushnal.me/

2 1

(no subject)
by Sakshi Singh 19 Mar '21

19 Mar '21

Hello Sir/Mam I'm Sakshi Singh Dangi from India l'm interested in one of your project bit I don't know what to do regarding application process please guide me.

1 0

[GSoC'21] Boost.Math : FFT Utilities PROJECT 1 Guidance
by Tushar k 19 Mar '21

19 Mar '21

Hello, I am Tushar Khandelwal from BITS Pilani 2019 batch, I am working with C++ for the past 2 years so I have a decent understanding of C++. In the past few days, I went through different boost libraries and different project ideas. So, I liked one of the projects of Boost.Math library: FFT Utilities, I have studied Fast Fourier Transform a few months back in my university course signals and system, also I have read many different articles and videos related to this beautiful concept. I have some doubts related to it like what exactly are your expectations from this project? how should I proceed? So I request a potential mentor of this project Christopher Kormanyos or others to please guide me. thanks! Looking forward to this open-source project in GSoC'21. With regards Tushar Khandelwal

3 2

Re: [boost] [release] 1.76.0 post-beta merges
by Glen Fernandes 18 Mar '21

18 Mar '21

John Maddock wrote: > I've had a request to merge these new Boost.Config feature > checks to release as Serialization depends on them: > https://github.com/boostorg/config/pull/369 > Also related to Serialization, this bugfix for BOOST_HAS_HASH should > probably go in: https://github.com/boostorg/config/pull/374. OK to merge both. Glen

1 0

[asio] [regex] 1.76.0 beta 1 compilation failure
by Scott Determan 18 Mar '21

18 Mar '21

There appears to be a problem compiling a program that includes both asio and regex in 1.76.0 beta 1. The following program fails to compile: ``` #include <boost/asio.hpp> #include <boost/regex.hpp> int main(int argc, char** argv) { return 0; } ``` The error is: ``` /home/swd/projs/common/boost_1_76_0_b1/boost/regex/v5/match_flags.hpp:38:14: error: multiple definition of ‘enum boost::regex_constants::_match_flags’ 38 | typedef enum _match_flags | ^~~~~~~~~~~~ In file included from /home/swd/projs/common/boost_1_76_0_b1/boost/asio/detail/regex_fwd.hpp:21, from /home/swd/projs/common/boost_1_76_0_b1/boost/asio/read_until.hpp:23, from /home/swd/projs/common/boost_1_76_0_b1/boost/asio.hpp:146, from ../src/main.cpp:2: /home/swd/projs/common/boost_1_76_0_b1/boost/regex/v4/match_flags.hpp:38:14: note: previous definition here 38 | typedef enum _match_flags ```

4 4

(GSoC '21) uBlas Project 2/3 Guidance
by Laxman 18 Mar '21

18 Mar '21

Hi, I, Laxman Desai, am interested in ublas Project 2 and 3. I’ve built a few C++ libraries before (for personal use) and I am familiar with C++17, MATLAB, TensorFlow, NumPy and Pandas to a good extent. I am currently learning R. I also have a good mathematical background, especially in Linear Algebra. I have currently completed the Competency Test for uBlas, and would request the mentors: David Bellot, Cem Bassoy or Amit Singh to guide me further for Project 2: creating new matrix and vector types and Project 3: Finalize Dataframe Implementation. Project 2: I dont understand what experimental templates and ublas::experimental::matrix means. I although have a strong feeling that it just refers to the tensor implementation of the same. I haven’t used uBlas tensor_core before, so could a mentor explain further (a basic intuition of the improvement, and the workflow for this project)? I would also appreciate more information on submatrix, and its implementation! To my understanding, it is to solve the problem that C++ doesn’t allow overloading of the colon operator. Project 3: I also am interested in project 3 (Finalising the DataFrames Implementation), and am currently exploring the available features. I have been using Pandas for a while now, and recently learnt R. “Finalize and productionize” seemed a bit vague to me, could I get more information on what all the current implementation is lacking (except for documentation)? I would also like to know if the mentors have a shortlist of features to add in mind? Any feedback on this would be greatly appreciated. Kind Regards, Laxman Desai Mail: desai.laxman2001(a)gmail.com

1 0

SVN/Trac account settings not accessible
by Andrey Semashev 17 Mar '21

17 Mar '21

Hi, It looks like SVN/Trac manager is no longer working. Is there a way to change account password?

1 1

Remove obsolete Coding Guidelines for Integral Constant Expressions
by Nikita Kniazev 17 Mar '21

17 Mar '21

Boost Library Requirements and Guidelines has a page https://www.boost.org/development/int_const_guidelines.html which contains highly outdated information. I think the guideline no longer applies and should be simply removed.

1 0

[GSoC'21] Seeking Further Guidance for Project3:Finalize Dataframe Implementation (Boost.uBlas: Matrix and Tensor Computations)
by Kowndinya Renduchintala 17 Mar '21

17 Mar '21

Hi Community! I am Kowndinya Renduchintala, a Second Year Undergraduate majoring in Computer Science and Engineering at Indian Institute of Technology Bombay. I am completely new to Open Source Software Development. Having worked on C++ extensively for the last two years of my Undergraduate studies, I consider myself a proficient C++ programmer. I also had a great amount of exposure in Math, specifically in Linear Algebra and Calculus. This led me to do more work related to them and I started working in the field Data Science where I have largely used Python’s numpy and pandas libraries, also MATLAB in some cases. I am very much interested in developing equivalent capabilities of above mentioned libraries in C++ too! I have gone through the Project Description on the GSoC’21 Ideas Page, and I am highly delighted to see that “Project:3 Finalize Dataframe Implementation” (in Matrix and Tensor Computation category), matches my interests to a very large extent. I am also ready to spend 40-50 hours per week for the completion of the project, thereby helping in productionizing the code by the end of the GSoC’21. But I have some questions left out in my mind after reading the “Project Description” and the “Competency Test” following it. The description says- “add a collection of free form functions, modern data analysis procedures (as found in R tidyverse, in Python pandas/numpy, and in many other packages)”. 1. Do the mentor(s) have some preconceived “list” of the sort of functions to be implemented, or am I expected to include the details of “my” ideas in the project proposal that I submit to Google starting from Mar29 to Apr13? 2. Is the Competency Test(providing matrix and vector C++17 implementation similar to MATLAB syntax) meant for giving us a taste for how the work in actual project is going to look like? If it is the case, then I am highly interested to work on such things/ similar things for that matter. I request David Bellot(The Potential Mentor as per the Wiki page) or any one else who is involved with the above project to please guide me further. After clarifying above two questions, I can straight away get into business and start the work, try to make a list of deliverables and probably ask more “technical” questions that I have in the code base, in my next mail. Looking forward to collaborate with Boost.uBlas and successfully complete my first Open Source Software Development project at GSoC’21 in my most favourite programming language!!! Regards Kowndinya Renduchintala rharisrikowndinya333(a)gmail.com Sent from [1]Mail for Windows 10 References 1. https://go.microsoft.com/fwlink/?LinkId=550986

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[sort] How does pdq-sort allocated memory?
by Viktor Sehr 17 Mar '21

17 Mar '21

According to the documentation boost::pdq_sort uses Log N additional memory. Assuming this memory is allocated via new, is it possible to pass an allocator, or even better, a pre-reserved std::vector<T> to the algorithm in order to avoid allocation? I could not find anything in the documentation about this. /VIktor

1 0

Confusion regarding projects
by Ameya Chawla 17 Mar '21

17 Mar '21

Respected sir/madam I want to contribute to Boost C++ libraries , but i am confused that do I have to contribute to all the 3 projects mentioned in Boost.uBlas <https://github.com/boostorg/ublas>: Matrix and Tensor Computations or I can contribute to any one of them .and competency test is for project 2 only or for all 3 projects ? https://github.com/CGAL/cgal/wiki/Project-Ideas Thank you

1 0

Confusion regarding projects
by Ameya Chawla 17 Mar '21

17 Mar '21

Respected sir/madam I want to contribute to Boost C++ libraries , but i am confused that do I have to contribute to all the 3 projects mentioned or I can contribute to any one of them .and competency test is for project 2 only or for all 3 projects ? https://github.com/CGAL/cgal/wiki/Project-Ideas Thank you

1 0

[release] Boost 1.76.0 beta 1 released
by Marshall Clow 16 Mar '21

16 Mar '21

Boost release 1.76.0 beta 1 is now available at: <https://dl.bintray.com/boostorg/beta/1.76.0.beta1/source/> The SHA256 checksums are as follows: 39eecd9672e78b95c8e3fdec1430a63788d528a66d3c8799c4639238e5d785bd boost_1_76_0_b1.7z c32edd34f767dd4bb67b86f76ebf58cf76822a5993a9b434c028b2dd08cfeefc boost_1_76_0_b1.zip 3ec1f92fa0a159b7073e39dd88f527a55d1f35e8986a3c560f202a75bdb8d584 boost_1_76_0_b1.tar.gz eb098d6d5352e10b17a3c49d2927ed61f09b6544f7c534627de35dfa2560fe20 boost_1_76_0_b1.tar.bz2 For details of what's in the release, see <https://www.boost.org/users/history/version_1_76_0.html>. Please download the beta, give it a try, and report any problems you encounter. Thanks, -- The Boost Release Team

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Introduction-Tushar Khandelwal
by Tushar k 16 Mar '21

16 Mar '21

Hi, I am Tushar Khandelwal from BITS Pilani 2019 Batch, I have a decent understanding of C++, I have been practicing C++ for the past 2 years, I am proficient in data structures and algorithms, I am new to open source and would love to contribute to this organization. How should I get started?

1 0

Headers only or .o
by Damian Vicino 15 Mar '21

15 Mar '21

Hi, I was reading the development section of the docs: https://www.boost.org/development/index.html And, I noticed there was nothing in the development guidelines about when to implement as headers-only vs built library. I got my own ideas of why most libraries are headers-only. But, I was wondering if someone with the historical context (someone who was here when those first libraries were developed) can share how boost got into the current shape and what new library developers should look into when deciding to go headers-only or not. I appreciate any anecdotes, guidelines, tradeoffs, thumb rules, comments on the topic. I would love to collect as much as possible here in this thread and write something to post in the development doc section in the website for future reference. Best, Damian

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[Describe] Review - Part 2: Class types
by Andrzej Krzemienski 15 Mar '21

15 Mar '21

Hi Everyone, Some feedback from playing with Boost.Describe for class types. 1. As others pointed out, it is confusing that BOOST_DESCRIBE_STRUCT() and BOOST_DESCRIBE_CLASS() have such close names, but their interface and requirements are so different. Maybe rename the latter to BOOST_DESCRIBE_THIS_CLASS()? 2. Base class subobjects are in some applications treated equivalently to member subobject; this is why I found it surprising that I cannot get the names of base class subobjects. But I guess there are implementation difficulties. Bases can be qualified names. 3. As with enums, _public_member_descriptor_fn in global namespace is UB or invalid program as per http://eel.is/c++draft/lex.name#3.2. 4. As others pointed out, the part of the interface that uses enum modifiers is not intuitive. I think that after a while it starts to make sense: you decide on your use case (like doing RPC), form your enum bitmask, and then pass it everywhere. It became more-less clear to me only after I had a look at the implementation of member_filter: https://github.com/pdimov/describe/blob/develop/include/boost/describe/memb… Maybe it makes sense to expose this in the docs. 5. Modifier mod_inherited is great for flattening the inheritance structure: struct X { int a; }; struct Y : X { int b; }; struct Z : Y { int c; }; BOOST_DESCRIBE_STRUCT(X, (), (a)); BOOST_DESCRIBE_STRUCT(Y, (X), (b)); BOOST_DESCRIBE_STRUCT(Z, (Y), (c)); int main() { namespace desc = boost::describe; using namespace std::literals::string_literals; constexpr auto mod = static_cast<desc::modifiers>(desc::mod_public | desc::mod_inherited); using L = desc::describe_members<Z, mod>; assert((boost::mp11::mp_at_c<L, 0>::name == "a"s)); assert((boost::mp11::mp_at_c<L, 1>::name == "b"s)); assert((boost::mp11::mp_at_c<L, 2>::name == "c"s)); } But it is not obvious at first. I recommend that the docs provide an example like this. It even works when base classes have members with same names: struct X { int a; }; struct Y { int a; }; struct Z : X, Y { int b; }; BOOST_DESCRIBE_STRUCT(X, (), (a)); BOOST_DESCRIBE_STRUCT(Y, (), (a)); BOOST_DESCRIBE_STRUCT(Z, (X, Y), (b)); int main() { constexpr auto mod = static_cast<describe::modifiers>(describe::mod_public | describe::mod_inherited); using L = describe::describe_members<Z, mod>; Z z = {{{3}}, {{6}}, {9}}; assert((z.*mp_at_c<L, 0>::pointer == 3)); assert((z.*mp_at_c<L, 1>::pointer == 6)); assert((z.*mp_at_c<L, 2>::pointer == 9)); } 5. What is the use case for modifier mod_hidden? I cannot think of any situation where I would need it. 6. Regarding the overloaded functions, I am no expert in preprocessor metaprogramming, but maybe if there was a way to provide function signatures along the name, you would have enough information to form the pointers. Something like: struct X { void f(int){} void f(void*){} }; BOOST_DESCRIBE_STRUCT(X, (), ( SIGNATURE(void f(int)), SIGNATURE(void f(void*)) ); 7. Modifier mod_virtual works unintuitively. It does not affect the filtering in describe_bases<>. It is only used for decorating the list elements. Maybe the docs should be more explicit about what it is used for. Again, is there a use case for this? Regards, &rzej;

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GSoC'21 boostorg timeline
by Krushnal Patel 15 Mar '21

15 Mar '21

Hi, I wanted to inquire about the GSoC'21 timeline specific to boostorg. I have gone over the GSoC'21 timeline but are there any specifics decided by boost regarding project selection, pre-proposal submission, proposal overview, programming competency test submission, etc? I am asking this question because as I was going over last years' mailing list I found a post where 'pre-proposal submission' was discussed so I started researching more about any timeline released specifically by boost but did not find any. Thanks in advance. Krushnal Patel, http://krushnal.me/

2 1

Requirement of mentorship for Generic Image Library project
by Aditya Tiwari 15 Mar '21

15 Mar '21

Hello there, I am Aditya Tiwari, a GSoC aspirant. I am interested in contributing to the Boost C++ library on the project "*Generic Image Library*". The knowledge requirement for this project is C++ and understanding of basic image processing algorithms, and I have a good knowledge of these two. I have been coding in C++ for over two years, with prior experience working with Boost libraries and working on projects related to image processing for over 1 year. I have read the problem statement and under GIL there's a project 2 about implementing image processing algorithms and in that list I know quite a bunch of algorithms. Also the project 1 under GIL, is quite a confusing task for me like do we have to add more and efficient algorithms here or something else? It would be very helpful if you can guide me through this project. I am open to any suggestions and I shall proceed with the task upon your acknowledgement. Regards, Aditya

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Re: [boost] [release] Boost 1.76.0 Beta 1 Release Candidate 1: fixed std::allocator deprecation-warning
by Löw, Tobias (STEAG Energy Services GmbH) 15 Mar '21

15 Mar '21

Hi, I've made a fix for the deprecation-warning: boost\unordered\detail\implementation.hpp(1452,7): warning C4996: 'std::allocator<T>::is_always_equal': warning STL4010: Various members of std::allocator are deprecated in C++17. Use std::allocator_traits instead of accessing these members directly. You can define _SILENCE_CXX17_OLD_ALLOCATOR_MEMBERS_DEPRECATION_WARNING or _SILENCE_ALL_CXX17_DEPRECATION_WARNINGS to acknowledge that you have received this warning. The PR is here: https://github.com/boostorg/unordered/pull/21 Tobias

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[release] Boost 1.76.0 Beta 1 Release Candidate 2
by Marshall Clow 13 Mar '21

13 Mar '21

The second release candidates for the 1.76.0 beta release are now available at: <https://dl.bintray.com/boostorg/beta/1.76.0.beta1/source/> The SHA256 checksums are as follows: c32edd34f767dd4bb67b86f76ebf58cf76822a5993a9b434c028b2dd08cfeefc boost_1_76_0_b1_rc2.zip eb098d6d5352e10b17a3c49d2927ed61f09b6544f7c534627de35dfa2560fe20 boost_1_76_0_b1_rc2.tar.bz2 39eecd9672e78b95c8e3fdec1430a63788d528a66d3c8799c4639238e5d785bd boost_1_76_0_b1_rc2.7z 3ec1f92fa0a159b7073e39dd88f527a55d1f35e8986a3c560f202a75bdb8d584 boost_1_76_0_b1_rc2.tar.gz The only changes from RC1 is an update to Boost.Interprocess, which was failing to compile on Mac OS X. As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. -- The Release managers

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Master branch now closed for 1.76.0 beta release
by Marshall Clow 13 Mar '21

13 Mar '21

Please do not make any commits to the master branch. — Marshall

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Re: [boost] FFT proposal for gsoc 2021
by Janek Kozicki 13 Mar '21

13 Mar '21

> Strongly and beneficially Influence that. But we still need > To adhere to all formal application Steps A note regarding these formal steps: https://github.com/boostorg/wiki/wiki/Google-Summer-of-Code%3A-2021 https://lists.boost.org/Archives/boost/2021/02/250876.php https://www.boost.org/users/faq.html > On the board. I can do 1 mentor of Either quad double or FFT. Yeah, both of them are very useful for me. If we make FFT this year, we can hope for quad-double next year :-) best regards Janek Christopher Kormanyos said: (by the date of Fri, 12 Mar 2021 16:00:38 +0100) > We still need to adhere to the > Formal application process > And we should have our dialog > On the board. I can do 1 mentor of > Either quad double or FFT. > > Having your own idea and a > Working model is a tremendous > Advantage in the application > Process and is likely to very > Strongly and beneficially > Influence that. But we still need > To adhere to all formal application > Steps > > Kindest regards, Chris > > Sent from my iPhone > > > On 12. Mar 2021, at 07:26, Eduardo Quintana <eduardo.quintana(a)pm.me> wrote: > > > > Dear Christopher, > > > > I am thrilled to hear from you! Thank you for offering mentorship for this > > project. I look forward to start working on it. > > > > Best regards, > > Eduardo > > > >> On Thu, Mar 11, 2021 at 06:55:37PM +0000, Christopher Kormanyos wrote: > >> > >> <html><head></head><body><div class="ydpad5c413ayahoo-style-wrap" style="font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:16px;"><div></div> > >> <div dir="ltr" data-setdir="false"><div>> Hi Boost community,<br><div>> I've been working on a C++ templated library</div><div>> for Fast Fourier Transforms</div><div><br></div><div>> ...<br></div></div><div dir="ltr" data-setdir="false"><span>> Is there anyone interested in supervising this</span></div><div dir="ltr" data-setdir="false"><span>> project? Any opinions?</span></div><div dir="ltr" data-setdir="false"><span><br></span></div><div dir="ltr" data-setdir="false"><span>Thank you for your interest and query.<br></span></div><div dir="ltr" data-setdir="false"><span><br></span></div><div dir="ltr" data-setdir="false"><span>Yes. I think I am interested and potentially qualified</span></div><div dir="ltr" data-setdir="false"><span>as 5 time GSoC mentor in Multiprecision and Math.</span></div><div dir="ltr" data-setdir="false"><span><br></span></div><div dir="ltr" data-setdir="false"><span>The plan seems good, start with header only</span></div><div dir="ltr" data-setdir="false"><span>simple implementation and increase complexity</span></div><div dir="ltr" data-setdir="false"><span>and efficiency as time allows.</span></div><div dir="ltr" data-setdir="false"><span><br></span></div><div dir="ltr" data-setdir="false"><span>This project would fill a present gap and wish list</span></div><div dir="ltr" data-setdir="false"><span>entry in Math/Multirpecision for those unable/unwilling</span></div><div dir="ltr" data-setdir="false"><span>to include FFTW.</span></div><div dir="ltr" data-setdir="false"><span><br></span></div><div dir="ltr" data-setdir="false"><span>I will write a little project description at rthe relevant</span></div><div dir="ltr" data-setdir="false"><span>page, link will follow...<br></span></div><div dir="ltr" data-setdir="false"><span><br></span></div><div dir="ltr" data-setdir="false"><span>Feel free to continue this thread, at the moment, i'm</span></div><div dir="ltr" data-setdir="false"><span>too busy to put down all my thoughts...<br></span></div><div dir="ltr" data-setdir="false"><span><br></span></div><div dir="ltr" data-setdir="false"><span>Kind regards, Christopher</span><br></div></div><div><br></div> > >> > >> </div><div id="yahoo_quoted_5520563993" class="yahoo_quoted"> > >> <div style="font-family:'Helvetica Neue', Helvetica, Arial, sans-serif;font-size:13px;color:#26282a;"> > >> > >> <div> > >> On Thursday, March 11, 2021, 10:55:29 AM GMT+1, Eduardo Quintana via Boost <boost(a)lists.boost.org> wrote: > >> </div> > >> <div><br></div> > >> <div><br></div> > >> <div>Hi Boost community,<br><br>I've been working on a C++ templated library for Fast Fourier Transforms,<br>https://github.com/Lagrang3/fftx.<br>Templated because some FFT algorithms are algebraic-field independent, eg. you<br>could FFT an array of N matrices provided a Nth matrix-root-of-unity is given.<br>As a result you could have a single algorithm for a variety of underlying, eg.<br>`std::complex<float>`, `std::complex<double>`, `std::complex<long double>`,<br>`boost::math::quaternion`, finite field types (this would yield the "Number<br>theoretic transform" <a href="https://cp-algorithms.com/algebra/fft.html#toc-tgt-6" target="_blank">https://cp-algorithms.com/algebra/fft.html#toc-tgt-6</a>).<br><br>I would like to improve this library during the GSOC 2021, as a proposal for<br>inclusion inside Boost.Math or Boost.Algorithms.<br><br>Is there anyone interested in supervising this project? Any opinions?<br><br>Best regards,<br>Eduardo Quintana<br><br>_______________________________________________<br>Unsubscribe & other changes: <a href="http://lists.boost.org/mailman/listinfo.cgi/boost" target="_blank">http://lists.boost.org/mailman/listinfo.cgi/boost</a><br></div> > >> </div> > >> </div></body></html> > > <publickey - eduardo.quintana(a)pm.me - 341e5416.asc> > -- -- Janek Kozicki, PhD. DSc. Arch. Assoc. Prof. Gdańsk University of Technology Faculty of Applied Physics and Mathematics Department of Theoretical Physics and Quantum Information -- http://yade-dem.org/ http://pg.edu.pl/jkozicki (click English flag on top right)

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[GIL] 2D Convolution/Correlation Proposal for gsoc 2021
by Gaurav kumar 12 Mar '21

12 Mar '21

Hi, I am Gaurav Kumar; I have been working on the Boost.GIL library for the past month. I would like to work on the 2D convolution/Correlation project. The ideas for the project are as follows: 1. Separable Kernels <http://www.dspguide.com/ch24/3.htm>: Most of the standard kernels (e.g. Gaussian, Sobel) can be separated into 2 or more 1D filters. For a N x N kernel, separating it into two 1D filters, the number of computations required would now be proportional to 2*N instead of N*N for the naive implementation. This implementation would also favor code reusability as this would only require a kernel separating function and driver code for a group of 1D filters. 2. Generic Implementation for 2D convolution: There are more generic kernels that are non-separable (e.g. Laplacian operator). In this case, the naive approach has already been implemented. The main task would be to provide the same set of functions as in the 1D convolution/correlation implementation. One potential idea for optimization of 2D convolution is to use the Im2col <https://www.programmersought.com/article/6306124604/> operation, in which the input image is converted into a row of column vectors, where each column vector represents an image block for which convolution/correlation operation is to be performed. The kernel can also be flattened out in a similar manner, resulting in a 1D array. This results in the convolution operation being reduced to matrix multiplication, which can be handled efficiently by BLAS libraries <https://en.wikipedia.org/wiki/Basic_Linear_Algebra_Subprograms> ( Boost.uBLAS ). Please share any suggestions you would have, related to the ideas presented above, or regarding 2D convolutions in general. I am looking for a mentor to guide me through this project. Best Regards, Gaurav Kumar Github handle: https://github.com/gkumar28

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[release] Boost 1.76.0 Beta 1 Release Candidate 1
by Marshall Clow 12 Mar '21

12 Mar '21

The first release candidates for the 1.76.0 beta release are now available at: <https://dl.bintray.com/boostorg/beta/1.76.0.beta1/source/> The SHA256 checksums are as follows: a222d325cd3c9f66951ec9026eca6ff6f48dd563c9a025911d598d2aca8770ce boost_1_76_0_b1_rc1.tar.bz2 6b90b510a3de38fc30a071ac798da37545fb60a1d6b21aed1130b47c9c598977 boost_1_76_0_b1_rc1.zip b01627bd9ce934b092037da81696bb4482a44e6a31c8791dbed82eafe04b69fa boost_1_76_0_b1_rc1.tar.gz dbef57adbab1d4395d14000f0a2420fc82f87476e10d48359ceff7125a74b77a boost_1_76_0_b1_rc1.7z As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. -- The Release managers

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Endorsement, review manager sought for Boost.Mysql
by Ruben Perez 12 Mar '21

12 Mar '21

Hi all, I would like to propose a MySQL client library for Boost (under the original name of Boost.Mysql). It is a full implementation of the MySQL client protocol, based on Boost.Asio. It requires C++11. The library is at https://github.com/anarthal/mysql and the documentation is at https://anarthal.github.io/mysql/. Examples under https://anarthal.github.io/mysql/mysql/examples.html. The purpose of this library is to provide a low-level building block for applications or other libraries to interact with MySQL, in the same way Boost.Beast provides a way to interact with HTTP. It complies with Boost.Asio universal asynchronous model, and provides the usual sync and async overloads for every network operation. Some notes: - The scope of this library is limited to MySQL. Its value proposition is implementing the client protocol in an Asio-compliant way. Supporting any database other than MySQL is not in scope of this library. - This library does NOT make use of MySQL libmysqlclient C API. It provides a from-the-ground-up implementation of the MySQL client protocol. Features: - Text queries and server-side prepared statements. - Sync and async functions, following Boost.Asio's universal async model. You may use callbacks, Boost coroutines, futures, C++20 coroutines, or any completion handler that Asio adds support for. - Can be used with any Stream including TCP sockets, UNIX sockets and Boost.Beast TCP streams. - Supports MySQL 5.x, MySQL 8.x and MariaDB.

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[Boost][Describe] Has been ACCEPTED into Boost
by Richard Hodges 12 Mar '21

12 Mar '21

Dear all, I am pleased to announce that we have received 13 high quality reviews. There has been no dissent, with every reviewer recommending that Describe be accepted. Reviews that were sent to me privately have been forward to Peter for consideration. If you have submitted a review and I have not responded privately to thank you, then please accept my apology for this oversight. Thank you everyone for taking some of your valuable time to contribute. -- Richard Hodges hodges.r(a)gmail.com office: +442032898513 home: +376841522 mobile: +376380212

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[interprocess][managed_shared_memory] Memory allocation of managed shared memories
by Grimm, Matthias 12 Mar '21

12 Mar '21

Hi, I have a question regarding the interprocess library and the use of shared memories. When creating a boost::interprocess::managed_shared_memory it seems to be necessary to take some additional space into account. In my case the following approach works well: managed_shm = new ip::managed_shared_memory(ip::create_only, "shm_id", (vec_elems + 110) * (number_of_samples + 1)); Following this it seems to be necessary to always have one additional element. If I remove the additional element (vec_elems + 110) * (number_of_samples) an exception is thrown: boost::interprocess::bad_alloc. This is also the case if I change to (vec_elems) * (number_of_samples + 1) Does anybody know why it is necessary to have this additional space allocated? What is the exact minimum size to avoid the exception? The additional memory may become a problem if the size of the vector elements is large. Attached you'll find some example code. Any help on this topic would be appreciated.

1 0

GSoC'21
by Manan Sharma 12 Mar '21

12 Mar '21

Hey, My name is Manan Sharma, I went through the project ideas for the GSoC'21 and the Multiprecision project really caught my eye. So I would like to contribute to this project but do not know where to start. I have basic knowledge of C++ like Template Programming. So I would appreciate it if anyone could tell me how to get started. Looking forward to contributing to the project. Yours sincerely, Manan Sharma Phone No.: +91 9711306818 Email Id.: manan180796(a)gmail.com

2 1

Queries regarding Contributing to boost open source library
by Tirtharaj Sen 12 Mar '21

12 Mar '21

Hello, I'm Tirtharaj Sen I wanted to know that I will start to contribute to boost open source library from today , so will can I make proposals for GSOC 2021 to the organisation or am I a bit late to start to contribute. I would also like to mention that I want to be associated with the organisation even after the GSOC is over. So does it require a 3 months of contribution history? Will be obliged if I get help from yours's side Thank you

2 1

Does anyone use mp11 with VS2013?
by Peter Dimov 11 Mar '21

11 Mar '21

Does anyone here use mp11 with Visual Studio 2013? (msvc-12.0) 2013 kind of supports C++11 but only barely, and I keep bumping into its bugs and limitations, so I'm considering dropping it and making 2015 the minimum requirement.

1 0

[Boost] [Describe] library submission - last call for reviews from the community
by Richard Hodges 11 Mar '21

11 Mar '21

A friendly reminder that the review period for [Boost.Describe] will finish at the end of tomorrow - 10th March 2021 We've had some excellent feedback already, and would value more. If you can spare a few hours of your valuable time, please consider reviewing this neat little library and posing your results on this mailing list. The invitation is repeated below: The Boost formal review of the Describe starts Monday, taking place from March 1st, 2021 to March 10th, 2021 (inclusive). The library is authored by Peter Dimov. Documentation: https://pdimov.github.io/describe/doc/html/describe.html Source: https://github.com/pdimov/describe The library provides a simple means of providing reflection for structures and enums in C++. The documentation contains a number of common motivating examples, including: - A universal print function https://pdimov.github.io/describe/doc/html/describe.html#example_print_func… - JSON serialisation https://pdimov.github.io/describe/doc/html/describe.html#example_to_json Please provide in your review information you think is valuable to understand your choice to ACCEPT or REJECT including Describe as a Boost library. Please be explicit about your decision (ACCEPT or REJECT). Some other questions you might want to consider answering: - What is your evaluation of the design? - What is your evaluation of the implementation? - What is your evaluation of the documentation? - What is your evaluation of the potential usefulness of the library? - Did you try to use the library? With which compiler(s)? Did you have any problems? - How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? - Are you knowledgeable about the problem domain? More information about the Boost Formal Review Process can be found at: http://www.boost.org/community/reviews.html The review is open to anyone who is prepared to put in the work of evaluating and reviewing the library. Prior experience in contributing to Boost reviews is not a requirement. Thank you for your efforts in the Boost community. They are very much appreciated. Richard Hodges - review manager of the proposed Boost.Describe library Peter is often available in the CppLang Slack #boost channel should you require any clarification not covered by the documentation, as am I. Please submit your review to the Boost mailing list: boost(a)lists.boost.org -- Richard Hodges hodges.r(a)gmail.com office: +442032898513 home: +376841522 mobile: +376380212

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[release] Reminder about 1.75.0 release notes
by Marshall Clow 11 Mar '21

11 Mar '21

The master branch is closing on Wednesday for the 1.75.0 release. If you have information that should go into the release notes, now’s the time to add it. Create a PR against https://github.com/boostorg/website/blob/master/feed/history/boost_1_75_0.q… <https://github.com/boostorg/website/blob/master/feed/history/boost_1_75_0.q…> — Marshall

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[release] Release notes for 1.76.0
by Marshall Clow 11 Mar '21

11 Mar '21

If you have information that should go into the release notes, now’s a good time to add it. Create a PR against https://github.com/boostorg/website/blob/master/feed/history/boost_1_76_0.q… — Marshall

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[Geometry] Proposing a project idea for GSOC 2021
by Siddharth Kumar 11 Mar '21

11 Mar '21

Hey, This is Siddharth Kumar. I have been working on the Boost.Geometry library for the past 2-3 months. I would like to propose a project idea about adding features for 3d-geometries, especially polyhedral surfaces which includes:- 1. Defining a geometry for the polyhedral surfaces. 2. Read and write features for the polyhedral surfaces. 3. Defining functions for the properties of polyhedral surfaces like volume, surface area, etc. This implementation will help in the direct use of the geometry in such algorithms, which are not yet implemented for the 3d-geometries or don’t provide compatible results when working with 3d-shapes, as they give points as an output rather than taking a geometry. For example- The convex hull <https://github.com/boostorg/geometry/issues/683> doesn’t handle 3d geometries correctly, because there is no 3d geometry defined that can handle the result of the algorithm. I have already submitted a PR <https://github.com/boostorg/geometry/pull/789> (yet to be merged), which defines the geometry for polyhedral surfaces, and also includes wkt read and write features, I am willing to work on other properties of the polyhedral surfaces as a project for GSOC 2021. I am looking for a mentor who is willing to guide me in this project. Thanks

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[Describe] Andrzej's review.
by Andrzej Krzemienski 10 Mar '21

10 Mar '21

Hi Everyone, This is my review of the Boost.Describe library. I recommend that the library should be **ACCEPTED** into Boost. The goal of the library is clearly specified, and addresses real world needs. The examples (JSON serialization, printing) are convincing, and the number of reviews saying "I needed it for a while" reassure that it will be useful. The library is well designed. I mean the separation into macros declaring the "reflection lsts", and then functions operating on those lists. The documentation, in connection with the clear design, makes it easy to learn and use the library. The only issues I had was with the modifiers enum: I had to look into the implementation to understand how some values work. Regarding the implementation, I only had a superficial look. One thing I observed is that the implementation is very short! When I tried to combine all headers into one, in order to test it on WandBox, I discovered that it is less than 600 lines. You can see it here: https://wandbox.org/permlink/rkAtPCbAsqNzVRMV The only issue I have is the names that start with the underscore that can potentially end up in the global namespace, which by my reading of the C++ Standard is UB. I have spent a couple of hours testing toy examples, reading the docs, and looking at the implementation. I used GCC 9.2.0 on MinGW and GCC 10.1.0 on WandBox. All worked fine. Regarding my previous concerns about the "N+1" problem (an overlap with other libraries), I no longer have it. Boost.Describe is for class and enum authors to offer a reflection information for whoever wants it. A library like Boost.Fusion is for working with fusion sequences. Only as convenience, it provides a way to adapt a user defined class as a fusion sequence, but if it wants, it can use Boost.Describe lists as an alternative way of providing the adaptation. My two real-life use cases for a reflection like this was: 1. Adapting aggregates for Boost.Spirit. It looks like even Boost.FPR would do. 2. Printing and implementing swap() and hash() for my types. So far I had to do it manually, so I am looking forward to having this library in Boost. Finally, I would like to thank Peter for writing and sharing this library. Regards, &rzej;

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Boost accepted in Google Summer of Code 2021
by David Bellot 10 Mar '21

10 Mar '21

We're in again! https://github.com/boostorg/wiki/wiki/Google-Summer-of-Code%3A-2021 David

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[Boost] [Describe] Review Reminder
by Richard Hodges 10 Mar '21

10 Mar '21

A friendly reminder that the review period for [Boost.Describe] is half way through. We've had some excellent feedback already, and would value more. If you can spare a few hours of your valuable time, please consider reviewing this neat little library and posing your results on this mailing list. The invitation is repeated below: The Boost formal review of the Describe starts Monday, taking place from March 1st, 2021 to March 10th, 2021 (inclusive). The library is authored by Peter Dimov. Documentation: https://pdimov.github.io/describe/doc/html/describe.html Source: https://github.com/pdimov/describe The library provides a simple means of providing reflection for structures and enums in C++. The documentation contains a number of common motivating examples, including: - A universal print function https://pdimov.github.io/describe/doc/html/describe.html#example_print_func… - JSON serialisation https://pdimov.github.io/describe/doc/html/describe.html#example_to_json Please provide in your review information you think is valuable to understand your choice to ACCEPT or REJECT including Describe as a Boost library. Please be explicit about your decision (ACCEPT or REJECT). Some other questions you might want to consider answering: - What is your evaluation of the design? - What is your evaluation of the implementation? - What is your evaluation of the documentation? - What is your evaluation of the potential usefulness of the library? - Did you try to use the library? With which compiler(s)? Did you have any problems? - How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? - Are you knowledgeable about the problem domain? More information about the Boost Formal Review Process can be found at: http://www.boost.org/community/reviews.html The review is open to anyone who is prepared to put in the work of evaluating and reviewing the library. Prior experience in contributing to Boost reviews is not a requirement. Thank you for your efforts in the Boost community. They are very much appreciated. Richard Hodges - review manager of the proposed Boost.Describe library Peter is often available in the CppLang Slack #boost channel should you require any clarification not covered by the documentation, as am I. -- Richard Hodges hodges.r(a)gmail.com office: +442032898513 home: +376841522 mobile: +376380212

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[Describe] Review - Part 1: Enumerators
by Andrzej Krzemienski 10 Mar '21

10 Mar '21

Hi Everyone, This is part one of my review of Boost.Describe. I will focus only on dealing with enumerators. Working with C++ enumerations is harder than one might think, because they are not what many people believe. They are just a bunch of integral constants and an integral type. We can get things like this: enum Season { Spring = 1, Summer, Autumn, // British Fall = Autumn, // American Winter, }; struct Human { std::string name; Season born; }; int main() { Human h {}; inspect(h); } void inspect(Human h) { switch(h) { case Spring: case Summer: case Fall: case Winter: return; default: assert(false) } } I can trigger an assertion failure without even doing any cast, because enums can assume other values that those listed in the declaration. The low-level interface provided by Boost.Describe is able to manage all these aspects very nicely. If we call BOOST_DESCRIBE_ENUM on struct Season above, we will get a list of five elements and the user will have to decide what she wants to do with it. On the other hand, requesting that Boost.Describe should provide a higher level enum-to-string mapping seems to overlook the special rules of C++ enums. How do you want this function to behave if the input enum value is not found? What do you want the function to do if it finds more than one corresponding string? The interface of describe_enumerators<> is optimal. Macro BOOST_DESCRIBE_ENUM is redundant: BOOST_DESCRIBE_ENUM_CLASS can handle unscoped enumerations pretty well. Note that in C++11 you can use the qualified names of unscoped enumerators, like Season::Winter in the above example. After playing first with macros for describing structs, I was surprised that the syntax for describing enumerators doesn't use parentheses for the list of enumerators: BOOST_DESCRIBE_ENUM(X, (A, B, C)); // I somehow expected that to work. Describing enums from the global namespace introduces names starting with underscore (_enum_descriptor_fn) into global namespace. This is Undefined Behavior, and is likely to trigger some code sanitizers. Instead use an ugly name, like boost_describe_enum_descriptor_fn. I do not appreciate the BOOST_DEFINE_ macros for enumerations. We get as much as four of them, and neither is able to handle the use case that I consider basic, which I often have in my code: where I omit value zero and start from 1: struct Error { badSoething = 1, badSomethingElse, tooLongSomethng, ... }; So, I am not sure how many real life enums these macros cover. Regards, &rzej;

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[release] Reminder: Master branch closing WEDNESDAY 3/10 for 1.76.0 beta release
by Marshall Clow 10 Mar '21

10 Mar '21

Calendar here: https://www.boost.org/development/ <https://www.boost.org/development/> — Marshall

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Boost beast HTTP server
by Jupiter 09 Mar '21

09 Mar '21

Hi, I installed almost all boost libraries to a Ubuntu 18.04 machine to run services, but I could not find which Ubuntu boost package includes beast, I looked at Internet comments that the cmake seems only working for Windows, how can I build beast in Ubuntu if the beast is not available in any ubuntu boost packages? Also, appreciate links to download breast samples. Thank you very much. Kind regards, Jupiter

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Re: [boost] [Boost] [Describe] library submission - last call for reviews from the community
by Samuel DEBIONNE 09 Mar '21

09 Mar '21

> Please provide in your review information you think is valuable to > understand your choice to ACCEPT or REJECT including Describe as a > Boost library. Please be explicit about your decision (ACCEPT or REJECT). ACCEPT! Thank you Peter for submitting this library. > Some other questions you might want to consider answering: > - What is your evaluation of the implementation? TBH, I did not look at the code much, I expect a lot of preprocessor machinery to generate the metadata. > - What is your evaluation of the documentation? Clean and to the point. Maybe the section "Describing Class Types" could be split in "Describing Class Types" and "Reflecting Class Types" (usage of the description)? Nitpick: the code snippets are missing syntax highlighting. > - What is your evaluation of the potential usefulness of the library? Definitely useful. I see a bright future for this library especially if it makes it to the standard. I am not sure how compatible it is with the C++ Reflection TS though. Baby steps is probably the right approach for such a complex feature... > - Did you try to use the library? With which compiler(s)? Did you > have any problems? GCC 9.3 on Linux. I am not sure if the examples are integrated to the build system yet but compiling them was a no-brainer. > - How much effort did you put into your evaluation? A glance? A quick > reading? In-depth study? About two hours, playing with the examples and writing my owns. Like many previous reviewers, I got tricked with the modifiers of the class describer. The | operator might be a bit misleading because some modifiers (mod_function) actually reduce the scope of the description. Reflecting the name of the type would be a nice addition. I am not a big fan of the BOOST_DEFINE_*** macros -actually shouldn't they be BOOST_DESCRIBE_DEFINE_ENUM? But since we have definition macros for enums, for symmetry, how about definition macros for structures -Hana has BOOST_HANA_DEFINE_STRUCT? I wonder if "fixed enum" is a standard terminology? > - Are you knowledgeable about the problem domain? Just from a user perspective. I use Boost.Hana[1] to get some level of reflection on structures. This solution is more limited than the one proposed in Boost.Describe (e.g. does not support member functions out of the box). The scope of Boost.Hana is much larger though and reflection is more a side effect of the Struct concept than a goal of the library. I use Better Enums[2] to get reflection on enums. Magic Enum C++[3] is a more modern alternative. Both libraries offer more features out of the box (aka enum_to_string) but I understand that the purpose of Describe is to "establish a standard way of providing these reflection abilities" and the interface needs to remain minimal to be the common factor. I have a patched Boost.Serialization that supports generic serialization of Hana Struct, just to say that it's possible. Thanks, Samuel 1. https://www.boost.org/doc/libs/1_61_0/libs/hana/doc/html/group__group-Struc… 2. https://github.com/aantron/better-enums 3. https://github.com/Neargye/magic_enum

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[concept_check] Fix issue #31 for Boost 1.76?
by Mateusz Loskot 09 Mar '21

09 Mar '21

Hi. Since VS 2019 16.9.0 is out and rolling, can we put a priority on fixing this issue? https://github.com/boostorg/concept_check/issues/31 IOW, could the maintainers decide which of the discussed fixes they prefer and what PR has chance to be merged promptly for Boost 1.76? Best regards, -- Mateusz Loskot, http://mateusz.loskot.net

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New home for B2.
by René Ferdinand Rivera Morell 08 Mar '21

08 Mar '21

As some of you may have noticed, B2 has a new home outside the Boost organization at <https://www.bfgroup.xyz/b2/>. The goal of the move is to elevate B2 development above the constraints of the Boost structure. I.e. to make B2 not just the build system that Boost uses. The biggest change to make happen is that last week the B2 fork at < https://github.com/bfgroup/b2> became the base git repo of all existing B2 git repos. And hence it means that the git repo < https://github.com/boostorg/build> is now a fork. What does this mean going forward? This that will not change: * Boost will still get the build system from the same git repo as it does now. * The B2 documentation will still be included in the Boost releases. What will change (eventually), or has already changed: * Development has moved to the new B2 git repo. And hence PRs for B2 will need to be posted to the new repo. * The B2 mail list at < https://lists.boost.org/mailman/listinfo.cgi/boost-build> will be replaced by the GitHub discussion forums at < https://github.com/bfgroup/b2/discussions>. * The B2 version in Boost will be updated from the base git repo for releases of the B2 base only. I.e. a B2 release will get merged to the Boost develop branch. And from there to the master branch. * The Boost testing of B2 reported at < https://www.boost.org/development/tests/develop/developer/summary.html> will stop showing (and hence running) B2 tests.The testing has already moved to cloud CI. And expanded to cover more platforms than Boost usually tests. * The B2 web site at <https://boostorg.github.io/build/> will go away. * The issues at <https://github.com/boostorg/build/issues> will eventually go away (once I deal with enough of them). -- -- René Ferdinand Rivera Morell -- Don't Assume Anything -- No Supone Nada -- Robot Dreams - http://robot-dreams.net

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[Describe] Clarification on the library scope
by Andrzej Krzemienski 08 Mar '21

08 Mar '21

Hi Everyone, First of all, I wanted to thank Peter for writing and sharing this library. A number of people already indicated it is useful, and I also have use cases that would be addressed by this library. I would lie to clarify if my understanding of the scope of this library is correct. From the discussion so far, I understood that the goal is to provide a low-level minimum building block that enables writing more elaborate libraries for providing type introspection. The library gives me the following guarantee: if a user used macro BOOST_DESCRIBE_STRUCT for some type T (and there are no ODR violations) than I can use `boost::describe::members` to see what those members are: their name, their type, and a pointer. If I want to use this data in a convenient way, I have to use another library atop of Boost.Describe. For instance, when I need to observe struct X as a tuple of references, I will write my own library, which: 1. Checks if Boost.PFR can figure it out automagically. If so, use this magic 2. If not, resort to Boost.Describe, and based on its interface, form a tuple of references. Did I capture it correctly? In that case, requesting high-level features in Boost.Describe is against its design goals. It is a low-level piece, not necessarily to be used directly. Regard, &rzej;

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[Describe] Boost.Describe vs Boost.Fusion
by Andrzej Krzemienski 08 Mar '21

08 Mar '21

Hi Everyone (but mainly Peter), Boost.Spirit needs to have an index-based access to user defined types, as explained in the tutorial: https://www.boost.org/doc/libs/1_75_0/libs/spirit/doc/x3/html/spirit_x3/tut… Currently Boost.Spirit uses the interface of Boost.Fusion, and users are encouraged to use macros like BOOST_FUSION_ADAPT_STRUCT: https://www.boost.org/doc/libs/1_75_0/libs/fusion/doc/html/fusion/adapted/a… The first question is, can Boost.Describe's interface be plugged into Boost.Spirit? It is not that obvious to me for a couple of reasons. For instance, it would require an interface in Boost.Describe for answering the question, "has describe::members been specialized for type X"? The second question is, can is Boost.Describe capable of replacing the adapter macros in Boost.Fusion? For instance, Boost.Fusion allows the users to define and adapt a user defined type with one macro: https://www.boost.org/doc/libs/1_75_0/libs/fusion/doc/html/fusion/adapted/d… This is similar in concept to what macro BOOST_DEFINE_ENUM does for enums. What is the motivation behind allowing the definition of enums in this way but not classes (at least the aggregate classes). My general observation is that we have a number of libraries with overlapping goals: Boost.Describe, Boost.PFR, Boost.Fusion (the part for adapting UDTs) Maybe it is ok, but does it mean that there are so many incompatible use cases? Maybe there is a way to reduce this number. Regards, &rzej;

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[Boost] [Describe] Review starts Monday 1st March 2021 - 10th March 2021
by Richard Hodges 08 Mar '21

08 Mar '21

The Boost formal review of the Describe starts Monday, taking place from March 1st, 2021 to March 10th, 2021 (inclusive). The library is authored by Peter Dimov. Documentation: https://pdimov.github.io/describe/doc/html/describe.html Source: https://github.com/pdimov/describe The library provides a simple means of providing reflection for structures and enums in C++. The documentation contains a number of common motivating examples, including: - A universal print function https://pdimov.github.io/describe/doc/html/describe.html#example_print_func… - JSON serialisation https://pdimov.github.io/describe/doc/html/describe.html#example_to_json Please provide in your review information you think is valuable to understand your choice to ACCEPT or REJECT including Describe as a Boost library. Please be explicit about your decision (ACCEPT or REJECT). Some other questions you might want to consider answering: - What is your evaluation of the design? - What is your evaluation of the implementation? - What is your evaluation of the documentation? - What is your evaluation of the potential usefulness of the library? - Did you try to use the library? With which compiler(s)? Did you have any problems? - How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? - Are you knowledgeable about the problem domain? More information about the Boost Formal Review Process can be found at: http://www.boost.org/community/reviews.html The review is open to anyone who is prepared to put in the work of evaluating and reviewing the library. Prior experience in contributing to Boost reviews is not a requirement. Thank you for your efforts in the Boost community. They are very much appreciated. Richard Hodges - review manager of the proposed Boost.Describe library Peter is often available in the CppLang Slack #boost channel should you require any clarification not covered by the documentation, as am I. -- Richard Hodges hodges.r(a)gmail.com office: +442032898513 home: +376841522 mobile: +376380212

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[spirit] Custom error on rule level?
by Serguei TARASSOV 08 Mar '21

08 Mar '21

Hello, is it possible to have a custom error handler on the rule level (for every rule in the limit) ? Cannot find this point in docs/examples. I.e. when parsing following texts (// are inline comments): DO_JOB WITH not_a_opt1; // should raise "Option not_a_opt1 is unknown" DO_JOB WITH opt2 = 123; // should raise "Invalid value 123 for option opt2" Regards,

2 1

[build] Could not open a pull request
by Nikita Kniazev 05 Mar '21

05 Mar '21

It seems that forks of boostorg/build switched their parent automatically and I could not find a way to open a PR against boostorg/build. What is happening and how do I proceed?

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boost.log's text_multifile_backend is not performant on windows - perhaps it should be documented?
by Nicholas Neumann 05 Mar '21

05 Mar '21

I recently moved a project to boost.log from a homemade logger. I had something like text_multifile_backend, so finding that as a drop-in replacement was awesome. Unfortunately, the performance when using text_multifile_backend on windows is really bad, because the repeated file close operations (one per log record) are unusually slow on windows. Repeatedly logging a string to the same file via text_multifile_backend results in throughput of about 200 log entries per second. Just to quickly prove it is unique to windows, I made a simple program that just opens, appends a single line, and then closes, an ofstream in a loop. On a high-end windows machine with nvme ssd, 1000 iterations takes 2600ms. On an older linux box with a sata ssd, the same takes 16ms. What do others think about adding a note in the documentation about this performance issue? It's bad enough that I think anyone on windows would want to avoid the backend. It's not the backend's "fault" at all; I could see some options for improving performance of the backend on windows, but they definitely complicate the simplicity of the current approach. (Side note - in googling the issue, other projects have been bitten - notably mercurial on windows - https://gregoryszorc.com/blog/2015/10/22/append-i/o-performance-on-windows/ )

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[quickbook] Broken links generated in locally built docs
by Andrey Semashev 05 Mar '21

05 Mar '21

Hi, When I'm building QuickBook docs locally for Boost.Log, I'm seeing errors like the following in the end: Error: no ID for constraint linkend: "log.design". and so on for basically any section id that is used in the QuickBook [link] tag. In the resulting HTML documentation all such links point to the root directory where the HTML docs are located. Looking at the bin.v2/libs/log/doc/log_doc.xml file, for example, for the log.detailed.sink_frontends.sync is, it looks like <link> tags use the id that is specified in QuickBook: <link linkend="log.detailed.sink_frontends.sync"> but the actual section has a colon in front of the id: <section id=":log.detailed.sink_frontends.sync"> Is this a known issue and is there a workaround? I'm using DocBook XML from the Kubuntu package, which has version 4.5-9, and a freshly built QuickBook from develop. I used to build docs locally fine before, and did not change the configuration since, but I may have upgraded Kubuntu since I last built the docs. Thanks.

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[release] 1.76.0 closes for major changes TOMORROW
by Marshall Clow 04 Mar '21

04 Mar '21

When: Wednesday, Mar 3, 2021 Description: Release closed for major code changes. Still open for serious problem fixes and docs changes without release manager review. Full calendar at: https://www.boost.org/development/ <https://www.boost.org/development/> — Marshall

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Re: [boost] [Describe] Boost.Describe vs Boost.Fusion
by Nikita Kniazev 02 Mar '21

02 Mar '21

> Or have Spirit perform a check: if `describe::members` is found use it, otherwise fall back to Boost.Fusion. Spirit uses Fusion iterator_range internally, it will require to find/write a replacement that will work with both libraries.

1 0

AVL Databases and Boost Serialization in C++
by Benedict NNcNannara 02 Mar '21

02 Mar '21

AVL Databases were invented in C# and Java in 2016. More recently (2022) AVL Databases were invented in C++. They were a port of the C# code back to C++. In fact, the port was of a larger system - The Generic Language. Boost Serialization Library was used to serialize a general datatype t in set<t>. This applies to the C++ Variant of AVL Databases, The Generic Language Compiler uses AVL Databases to store its code. Execution occurs directly out of the code database, thus no loader is required. In fact the multithreaded, monolithic runtime is very fast compared to the C# version which is now obsolete. uuindouus.zip <https://drive.google.com/file/d/1NhEEmfZMf5yGbnsTAHH1N-XAjPCbczAy/view?usp=…>

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1.76 schedule?
by John Maddock 01 Mar '21

01 Mar '21

Just noticed that the calendar has master closed for breaking changes from yesterday... I was hoping to do a Math & Multiprecision release, but they drop C++03 and have some massive restructuring/changes as a result. On the plus side they're better tested than they probably ever have been. So... too late for 1.76 or not? Thanks, John. -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

4 4

feature for C++ standards compliance
by Robert Ramey 28 Feb '21

28 Feb '21

The serialization library is compatible with C++03 (and likely 98). And is tested regularly with C++ compilers with the -std switch set to this mode. The recent changes to the math library have broken about 5 tests in the serialization library. Since this breakage is in a few tests only and not in the library itself, I'd like to suppress these tests when the being tested with a C++03 compiler. I've suppressed tests which are conditional on C++ features which are not supported and this has worked well for my purposes. I'd like to do the same for a couple of tests which are conditional on usage of the math library and standards versions < C++11. Any B2/CMake experts want to help an old guy out?

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New PropertyTree maintainer
by Glen Fernandes 27 Feb '21

27 Feb '21

Richard Hodges has kindly agreed to become the new maintainer of Boost.PropertyTree. Many thanks, Richard. Please update meta/libraries.json accordingly. Glen

1 0

Google Summer of Code follow-up
by Radu Cosma 26 Feb '21

26 Feb '21

Dear all, A couple of weeks ago I wrote an email inquiring about how to approach applying to contribute to your project through the GSoC opportunity. I did not seem to get any responses, is this the right place to ask? If not, could you please point me to a contact person that I can talk to? I am very interesting in contributing to this project and would really like to know how I can help. I am extremely familiar with the entirety of the C++20 standard, besides some final template (and concepts) features that I am still learning about, and would love the challenge of using those skills in the context of contributing to the Boost libraries. Thank you in advance and have a nice day! Kind regards, Radu Cosma

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Introduction
by Samrat Patel 25 Feb '21

25 Feb '21

Hello Boost C++ Community, I am Samrat from Delhi Technology University and currently, I am pursuing my bachelor's in Computer Engineering(CoE). I have 3 years of experience in C++. I am extremely eager and excited about contributing to various projects of Boost C++. I am willing to participate in GSOC'21 with Boost C++. I would feel indebted if you could guide me in this regard. Regards Samrat Patel

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property_tree in need of a maintainer
by Richard Hodges 25 Feb '21

25 Feb '21

Dear all, I am offering to become the/a maintainer of property_tree as part of my work for the C++ Alliance. Sincerely, -- Richard Hodges hodges.r(a)gmail.com office: +442032898513 home: +376841522 mobile: +376380212

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Reminder: Describe needs a review manager
by Peter Dimov 25 Feb '21

25 Feb '21

This is a reminder that my library Describe https://github.com/pdimov/describe https://pdimov.github.io/describe/doc/html/describe.html needs a review manager. Describe is a library that allows programmers to annotate their classes (and enumerations) in order to enable simple reflection. It provides a very important fundament on which other libraries can build upon to provide automatic support for user-defined types. For example, given an annotated type, Boost.JSON can automatically provide conversions from/to json::value. Boost.ContainerHash can automatically provide a hash function hash_value for the type. Boost.Serialization can automatically provide serialization support. See the examples: https://pdimov.github.io/describe/doc/html/describe.html#example_to_json https://pdimov.github.io/describe/doc/html/describe.html#example_from_json https://pdimov.github.io/describe/doc/html/describe.html#example_serializat… Other JSON (and serialization) libraries already offer a similar mechanism, e.g. https://github.com/nlohmann/json#arbitrary-types-conversions. But since each library has its own private way to annotate types, a programmer needs to repeat the type annotations for every library he wants his type to be known to. This is unnecessary and undesirable, and a standard mechanism to describe types avoids it. Describe is intended to be this standard mechanism, and I believe that we need it in Boost sooner rather than later. Thanks in advance to whoever volunteers.

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Re: [boost] Reminder: Describe needs a review manager
by Bjorn Reese 25 Feb '21

25 Feb '21

On 2021-02-23 19:56, Peter Dimov via Boost wrote: > Describe is a library that allows programmers to annotate their classes > (and enumerations) in order to enable simple reflection. It provides a > very important fundament on which other libraries can build upon to > provide automatic support for user-defined types. How does it differ from Boost.Fusion?

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[boost-ext] Looking for Review Manager/s
by Krzysztof Jusiak 24 Feb '21

24 Feb '21

Hi, I just wanted to share, potentially useful for the Boost and C++ community, libraries and ask if anyone would be willing to become a Review Manager for any of them? [boost-ext] (https://github.com/boost-ext) is a collection of C++ libraries with aspirations to be included in Boost. Libraries can be characterized by: * Modern C++ (>= C++14) * Header/Single Module only * No dependencies ATM, [boost::ext] consists of four core libraries: * DI - Dependency Injection Library overview: standard: C++14 single header with no dependencies (neither STL nor Boost is required) release: 1.2.0 (first release - 2014) key features: - supports macro-free constructor injection - supports templates injection - quick compilation-times - highly optimized code generation try it online: https://godbolt.org/z/5qTKhf source code: https://github.com/boost-ext/di documentation: https://boost-ext.github.io/di/ * SML - State Machine Library overview: standard: C++14 single header with no dependencies (neither STL nor Boost is required) release: 1.1.4 (first release - 2016) key features: - much faster compilation-times than Boost.MSM (up to 60x faster) - highly optimized and customizable code generation - suitable for embedded systems try it online: https://godbolt.org/z/y99L50 source code: https://github.com/boost-ext/sml documentation: https://boost-ext.github.io/sml/ * UT - Unit Testing Framework overview: standard: C++20 single header with no dependencies (STL required) release: 1.1.8 (first release - 2019) key features: - macro-free - minimal boilerplate - fast compilation-times and execution try it online: https://godbolt.org/z/Jqb5Ye source code: https://github.com/boost-ext/ut documentation: https://boost-ext.github.io/ut * TE - Run-time polymorphism (type erasure) library overview: standard: C++17 single header with no dependencies (STL required) release: - key features: - simple interface - highly optimized code generation try it online: https://godbolt.org/z/xY9MEq source code: https://github.com/boost-ext/te documentation: https://github.com/boost-ext/te All libraries (except TE) were successfully deployed in the production systems. Some, such as DI and SML are used by well known/big IT companies as well. If anyone is interested in becoming a Review Manager for any of the libraries, I'd really appreciate it and I'll more than happy to address any issues/requests before the review as well as help with any process-related tasks. Thank you very much, -Kris

12 43

Getting stated with boost and CMake
by pbristow＠hetp.u-net.com 24 Feb '21

24 Feb '21

Having spent a decade watching the Cmake versus bjam/b2 battle, I had thought it wise to wait until the dust has settled. It would appear that the enthusiasm for CMake and Boost is much greater among consumers than producers ☹ But recently I have been working on a project that is possible Boost library and thought that I would dip my toe in the water. After some research, I am still puzzled how I should replace a simple b2/bjam program (say a classic “hello World”) that is run like this \example > b2 -a toolset=msvc,gcc,clang cxxstd=14 release > my_log.log The jamfile contains run hello_world.cpp ; # Simplest hello_world, no other includes apart from iostream. And the b2 run .log contains some outputs of "Hello world" and 3 nice **passed** lines and ...updated 3(?) targets..., one for each compiler (and version too, perhaps with some potentially using build info too), and return exit_success value. (I also would expect to get a simple setup to run a test using the /included version of unit_test_framework. Trying to walk before I fall over running, I have avoided any pre-compiler libraries, at least at first.) After some research (getting as far as generating a Visual Studio project, where I can intervene manually to build and run my hello_world program), I am still unclear how to replicate this b2 test to end with a .exe run and some log file with pass/fail indications. I am of course building on Windows 10 with three recent versions of MSVC, GCC and Clang compilers working, and in my bjam/b2 user-config.jam. Advice from less-than-novice CMakers most welcome. Thank you. Paul

1 0

GSoC 2021 new policies
by Pranam Lashkari 23 Feb '21

23 Feb '21

Hello, To all the potential mentors and students this year GSoC is different from all the previous seasons, so whenever you are planning/proposing/adding a project in GSoC this year, keep the following things in mind: *Smaller project size** - *all students participating in the 2021 program will be working on a 175 hour project (instead of a 350 hr project). *Shortened coding period* - the *coding period will be 10 weeks* with a lot more flexibility for the mentor and student to decide together how they want to spread the work out over the summer. *2 evaluations (instead of 3)* - There will be an evaluation after 5 weeks and the final evaluation will take place after the 10th week. -- Thank you, Pranam Lashkari, https://lpranam.github.io/

1 0

Releasing property_tree updates
by Jared McIntyre 20 Feb '21

20 Feb '21

I noticed there are several updates that have merged into the develop branch for property_tree, but it seems none of them have made it into master for release. Is there any chance that a new version with the fixes may be pushed out in a future release? Thanks, Jared

2 1

boost test: first test organization examples using deprecated init_unit_test_suite?
by Dennis Luehring 15 Feb '21

15 Feb '21

according to this example, i should use init_unit_test_suite https://www.boost.org/doc/libs/1_75_0/libs/test/doc/html/boost_test/tests_o… but it seems that init_unit_test_suite function is deprecated (starting with 1.59) https://www.boost.org/doc/libs/1_75_0/libs/test/doc/html/boost_test/adv_sce… so its unclear to me if i should (still) use this deprecated function or go witht BOOST_AUTO_TEST_SUITE/BOOST_AUTO_TEST_CASE

1 0

[build] "Unknown target type EXE"
by John Maddock 09 Feb '21

09 Feb '21

I've managed to get various architectures tested in qemu-emulation in this PR: https://github.com/boostorg/config/pull/366, with help from https://github.com/uraimo/run-on-arch-action However, for armv7 alone I see: /home/runner/work/config/boost-root/tools/build/src/build/type.jam:158: in type.validate from module type error: Unknown target type EXE (builtin):-1: in sequence.transform from module sequence /home/runner/work/config/boost-root/tools/build/src/build/generators.jam:239: in generator.__init__ from module object(installed-exe-generator)@4 /home/runner/work/config/boost-root/tools/build/src/tools/stage.jam:568: in class(a)installed-exe-generator.__init__ from module object(installed-exe-generator)@4 /home/runner/work/config/boost-root/tools/build/src/kernel/class.jam:90: in new from module class /home/runner/work/config/boost-root/tools/build/src/tools/stage.jam:596: in load from module stage /home/runner/work/config/boost-root/tools/build/src/kernel/modules.jam:295: in import from module modules /home/runner/work/config/boost-root/tools/build/src/tools/builtin.jam:27: in load from module builtin /home/runner/work/config/boost-root/tools/build/src/kernel/modules.jam:295: in import from module modules /home/runner/work/config/boost-root/tools/build/src/build-system.jam:12: in load from module build-system /home/runner/work/config/boost-root/tools/build/src/kernel/modules.jam:295: in import from module modules /home/runner/work/config/boost-root/tools/build/src/kernel/bootstrap.jam:139: in boost-build from module /home/runner/work/config/boost-root/boost-build.jam:17: in module scope from module This is while running ./b2 headers. The initialization/setup code is the same for each architecture as they're run in a GHA matrix so I don't think I've goofed in the CI script. Anyone any ideas what might cause this? Many thanks, John. -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

2 1

New Boost.Build regression/failure
by John Maddock 08 Feb '21

08 Feb '21

This: https://ci.appveyor.com/project/jzmaddock/config/builds/37592647/job/l6ogy7… Has just started failing. Any ideas anyone? Thanks, John. -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

4 8

[Flyweight] Hidden symbol visibility
by Deniz Bahadir 08 Feb '21

08 Feb '21

Hi there, I recently made some interesting observation regarding Boost.Flyweight and (hidden) symbol visibility and have now some questions regarding this. Background story: ----------------- In our company's code base we have been using Boost.Flyweight for several years now, compiling it with GCC (and Clang) and it worked just fine. (Thanks for it!) However, lately we are trying to apply hidden symbol visibility to our code base and some of our unit-tests started failing mysteriously. After some intensive investigation I found out that it seems to be due to how we used Boost.Flyweight. We are instantiating it with some custom types, using the default `boost::flyweights::static_holder` class, and are compiling it into a shared library A. However, these Boost.Flyweight types are not only used within that shared library A but also in some other shared library B and in some unit-test executables which link against shared library A. (And these unit-tests started failing.) Observations: ------------- Reading the documentation of Boost.Flyweight and looking at the header `boost/flyweight/static_holder.hpp` I realized that we should have used `boost::flyweights::intermodule_holder` in the first place instead of `boost::flyweights::static_holder`, because we were using Boost.Flyweight from different shared libraries. Still, with non-hidden visibility applied everything always worked correctly even when using `boost::flyweights::static_holder`. Looking at the generated symbols in the different shared libraries I realized that these `static_holder` class types were marked as "unique global symbol" (an GNU extension to the standard set of ELF symbol bindings). So, all shared libraries and executables still used the same single instance of that `static_holder` class (which is the reason why everything worked). With hidden symbol visibility applied by default, these symbols are now marked as local symbols (from the BSS section). So, each shared library as well as the executables have their own version of the `static_holder` class types (which would explain why the equality-comparisions between different Boost.Flyweight variables in our unit-tests now started failing). If I understand it correctly, using `boost::flyweights::intermodule_holder` is the right thing to do, in particular with hidden symbol visibility. Questions: ---------- 1. However, apart from longer program startup times, what other disadvantages might it have to use the `intermodule_holder` instead of the `static_holder` (assuming it still would be marked as "unique global symbol")? 2. And if, as it seems, `static_holder` has some advantages in general, would it be possible to (maybe conditionally) mark the `static_holder` (and/or `static_holder_class`) class with `BOOST_SYMBOL_VISIBLE` or something similar to allow using it even with hidden symbol visibility from different shared libraries? - Only applying default visibility to the template instantiations is ignored by GCC (with warning: "type attributes ignored after type is already defined [-Wattributes]"). - Besides, the C++ standard does not allow applying C++ attributes to template instantiations. (There was a proposal for allowing it, wg21.link/p0537, but I do not know what happened to it.) 3. Would you have any other recommendations or suggestions I did not think about? Thanks for any help or opinion, Deniz -- BENOCS GmbH Dipl.-Inform. Deniz Bahadir Reuchlinstr. 10 D 10553 Berlin Germany Phone: +49 - 30 / 577 0004-22 Email: deniz.bahadir(a)benocs.com www.benocs.com Board of Management: Stephan Schroeder, Dr.-Ing. Ingmar Poese Commercial Register: Amtsgericht Bonn HRB 19378

2 2

BinTray is going away....
by Marshall Clow 06 Feb '21

06 Feb '21

My Friday morning email: > Thank you for supporting JFrog through your use of Bintray. We are and continue to be a community-focused company, and in the spirit of transparency we’re giving you advance notice that as of May 2021, we will be sunsetting Bintray. Just a heads up for now. — Marshall

2 1

Wrong class export/visibility setting for shared libs in many Boost libs
by Alexander Grund 02 Feb '21

02 Feb '21

Hi Boost maintainers, TLDR: Check your classes if they use BOOST_*_DECL and change that to BOOST_SYMBOL_VISIBLE In Boost.ProgramOptions I discovered an issue as a user, where I was unable to catch an exception thrown from the shared Boost library in an executable when both are build with hidden visibility. It turns out the exception class was marked with BOOST_PROGRAM_OPTIONS_DECL which evaluates to "visible" when building the DLL but to nothing when using it. This makes the linker (in theory) mark the typeinfo as hidden which means that the class thrown by Boost and the one tried to catch are unrelated. See https://gcc.gnu.org/wiki/Visibility > Symbol visibility is "default" by default but if the linker encounters just one definition with it hidden - just one - that typeinfo symbol becomes permanently hidden (remember the C++ standard's ODR - one definition rule). This is pretty clear that the current approach done by some Boost libraries doesn't/shouldn't work and BOOST_SYMBOL_VISIBLE should be used instead (or BOOST_SYMBOL_IMPORT should expand to BOOST_SYMBOL_VISIBLE. This depends on how MSCV/Win32 platforms handle class visibility as on Win32 BOOST_SYMBOL_VISIBLE expands to nothing. Maybe someone can clarify here.) As another datapoint: https://github.com/boostorg/config/blob/5bcaa933b55dd58797775d87605a6cdef4a… documents BOOST_SYMBOL_VISIBLE as the macro to be used for this. Libraries which are (very likely) affected by this (quick grep) include: Chrono Container Context Contract Coroutine Fiber Filesystem IOStreams JSON Locale MPI ProgramOptions Python Regex Test Thread Timer Seemingly Linux platforms are less strict in actually enforcing this, due to reason unknown to me. See my SO question: https://stackoverflow.com/questions/65951466/why-can-a-thrown-exception-wit… Reason why this went undetected so far are the above (works on some Linux, fails on e.g. OSX) and that user programs may often not be build with hidden visibility AND rely on the exact same typeinfo from the Boost library (most prominent: exceptions, dynamic_cast) Regards, Alex

5 40

Re: [boost] Wrong class export/visibility setting for shared libs in many Boost libs
by Peter Dimov 02 Feb '21

02 Feb '21

E.g. https://godbolt.org/z/vM6Gxd -----Original Message----- From: Peter Dimov Sent: Tuesday, February 02, 2021 17:01 To: boost(a)lists.boost.org Subject: Re: [boost] Wrong class export/visibility setting for shared libs in many Boost libs Niall Douglas wrote: > I seem to be having difficulty communicating this to anyone here, so > here's a godbolt: > > https://godbolt.org/z/jv5Y75 But you've provided a definition for thirdpartylib_nothidden. This is not the case under discussion. The case under discussion is making BOOST_SYMBOL_IMPORT imply _VISIBLE, which translates to a default visibility attribute on the _declaration_ of thirdpartylib_nothidden.

1 0

Google Summer of Code
by Radu Cosma 30 Jan '21

30 Jan '21

Good afternoon, My name is Radu Cosma and I would like to be a contributor to the Boost C++ Libraries in the context of Google Summer of Code 2021 (as a start :) ). I understand that the topics have yet to be posted and that there is a competency test involved. Could you please tell me the relevant information regarding this and the application process? Thank you in advance! Kind regards, Radu Cosma

1 0

What's the reason Boost.Asio tss_ptr doesn't use __declspec(thread) on Windows?
by Groke, Paul 29 Jan '21

29 Jan '21

Hi, I've noticed that Boost.Asio's tss_ptr implementation doesn't use __declspec(thread) on Windows, except when compiling for WinRT. Instead it uses the win_tss_ptr implementation - which will cause a crash when there's no free TLS index. (There are static tss_ptr instances and loading a DLL where a ctor of a static variables throws a C++ exception seems to cause a crash -- no surprise there). AFAIK using implicit TLS via __declspec(thread) should fix this so that loading a DLL either works or fails gracefully. One problem that I know of with implicit TLS is that it fails catastrophically on Windows versions before Vista. Since WinRT wasn't available on pre-Vista versions, this might be a reason to restrict it to WinRT. But I don't know if there are/were other reasons to restrict use of implicit TLS to WinRT. So... is there another reason? If there's no other reason, that would be great, because we don't have to support pre-Vista versions. Meaning we could simply patch Boost.Asio to use implicit TLS for MSVC in general. Regards, Paul Groke

1 0

Have we become too Intel x64 centered?
by John Maddock 28 Jan '21

28 Jan '21

I have no solution for this, but I note that neither do we have CI, nor tests on https://www.boost.org/development/tests/develop/developer/summary.html that aren't Intel x86. The compiler list has shrunk to msvc/clang/gcc as well. I note that at least in theory, other platforms/architectures could be integrated into Drone CI (either the CppAlliance one, or our own), but someone would have to offer to host the clients running the tests. Any thoughts/solutions? Cheers, John. -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

21 54

Introduction
by Aman Verma 28 Jan '21

28 Jan '21

Hello Boost C++ Community, I am Aman from Indian Institute of technology Kanpur and currently, I am pursuing my bachelor's in Electrical engineering. I have 3 years of experience in C++. I am extremely eager and excited about contributing to various projects of Boost C++. I am willing to participate in GSOC'21 with Boost C++. I have gone through the project proposals and I find myself interested in the following projects: 1. ublas 2. Multiprecision 3. Geometry I would great if I could connect with the respective mentors and move onto further steps. Regards Aman

2 1

boost.numpy functions are throwing unresolved extern symbol link errors
by Max Fetz 20 Jan '21

20 Jan '21

Hello Boost-Community I have asked the following question everywhere but nowhere has it been answered. I have now been advised to ask here. I really hope there is someone on this mail list who can help me. Unfortunately I don't have much time left and would be very grateful for an answer. With kind regards Max My Question: I'm using normal Boost.NumPy functions in C++ like ndarray::get_data(), and I get a "reference to unresolved external symbol" error. The .lib's are linked and I have no approach on how to solve the error. I am using Boost 1.74. Here is a Code example: #include<boost/python/numpy.hpp> using namespace boost; void func(python::object _obj) { python::numpy::ndarray my_ndarray = python::extract<boost::python::numpy::ndarray>(_obj.attr("Member_01")); char* data = my_ndarray.get_data(); } BOOST_PYTHON_MODULE(ogwa_acc) { python::def("func", func); } Thats the one of the unresolved symbols: ""__declspec(dllimport) public: char * __cdecl boost::python::numpy::ndarray::get_data(void)const " (_imp?get_data@ndarray@numpy@python@boost@@QEBAPEADXZ)" I am using the normal Visual Studio linker and this is my linker config: /OUT:"D:\OthelloGame_withAI\x64\Debug\ogwa_acc.pyd" /MANIFEST /NXCOMPAT /PDB:"D:\OthelloGame_withAI\x64\Debug\ogwa_acc.pdb" /DYNAMICBASE "boost_numpy38-vc142-mt-gd-x64-1_74.lib" "boost_numpy38-vc142-mt-x64-1_74.lib" "boost_python38-vc142-mt-gd-x64-1_74.lib" "boost_python38-vc142-mt-x64- 1_74.lib" "kernel32.lib" "user32.lib" "gdi32.lib" "winspool.lib" "comdlg32.lib" "advapi32.lib" "shell32.lib" "ole32.lib" "oleaut32.lib" "uuid.lib" "odbc32.lib" "odbccp32.lib" /IMPLIB:"D:\OthelloGame_withAI\x64\Debug\ogwa_acc.lib" /DEBUG /DLL /MACHINE:X64 /INCREMENTAL /PGD:"D:\OthelloGame_withAI\x64\Debug\ogwa_acc.pgd" /SUBSYSTEM:CONSOLE /MANIFESTUAC:"level='asInvoker' uiAccess='false'" /ManifestFile:"x64\Debug\ogwa_acc.pyd.intermediate.manifest" /ERRORREPORT:PROMPT /NOLOGO /LIBPATH:"C:\Program Files\Python38\libs" /LIBPATH:"D:\OthelloGame_withAI\Third-Party\boost_1_74_0\finished_libs" /TLBID:1 D:\OthelloGame_withAI\Third-Party\boost_1_74_0\finished_libs is the location of: boost_numpy38-vc142-mt-gd-x64-1_74.lib; boost_python38-vc142-mt-gd-x64- 1_74.lib; boost_numpy38-vc142-mt-x64-1_74.lib; boost_python38-vc142-mt-x64-1_74.lib

4 4

[build] b2 headers broken?
by John Maddock 16 Jan '21

16 Jan '21

Currently all CI seems to be failing during b2 headers, but with no obvious error message, see for example: https://drone.cpp.al/boostorg/multiprecision/23/1/2 Only possible thing I can see is: project-config.jam:10: syntax error at keyword in Anyone any ideas? Many thanks, John. -- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

3 5

Feedback desired for neural networks library
by Sergei Marchenko 11 Jan '21

11 Jan '21

Hi everyone, I have a template-based library with several common types of layers which can be assembled into various neural networks: https://github.com/svm-git/NeuralNet, and I would love to get community feedback on the overall design, any issues or missing features, and how interesting a library like that would be in general. I've been watching the trends and research reports in the AI/ML space, and I feel that the recent announcements of the successful models for image classification, computer vision or natural language processing, push the focus towards very complex and computationally intensive networks. However, I think that the idea behind multi-layer networks is very powerful, and is applicable in many domains, where even a small and lightweight model can be used successfully. I also think that if developers have an access to a library of building blocks that allows them to train and run NN anywhere a C++ code can run, it may encourage a lot of good applications. In the current state, the library is fairly small and should be easy to review. It was built with two main goals in mind: * Provide a collection of building blocks that share a common interface which allows plug'n'play construction of more complex NNs. * Compile-time verification of the internal consistency of the network. I.e. if a layer's output size does not match the next layer's input, it is caught at the very early stage. Once it seems like there is some consensus on the core design and usefulness of such library, I am willing to do the work necessary to make the library consistent with Boost requirements for naming convention, folder structure, unit tests etc. The library relies on the C++ 11 language features and has a dependency on just a few STL components, so I think it should be straightforward to merge into Boost. Best regards, Sergei Marchenko.

6 15

Can boost ASIO SSL run one way SSL?
by Jupiter 11 Jan '21

11 Jan '21

Hi, There is an example for running boost::asio::ssl for boost::asio::ip::tcp connection, it uses 2 way SSL which client uses the key and certificates to have two way SSL handshake. My boss asked me if it can be used for one way SSL similar to HTTPS, I don't think so, but I could be wrong. Appreciate your advice. Thank you. Kind regards, jupiter

2 3

Problem building Ceph 14.2.15 with libboost 1.74.0
by Thomas Goirand 07 Jan '21

07 Jan '21

Hi, I'm the Debian package maintainer for Ceph. Ceph currently fails to build with latest libbost. Here's the build log: /root/ceph/src/common/async/completion.h:194:29: error: 'boost::asio::executor_work_guard<boost::asio::execution::any_executor<boost::asio::execution::context_as_t<boost::asio::execution_context&>, boost::asio::execution::detail::blocking::never_t<0>, boost::asio::execution::prefer_only<boost::asio::execution::detail::blocking::possibly_t<0> >, boost::asio::execution::prefer_only<boost::asio::execution::detail::outstanding_work::tracked_t<0> >, boost::asio::execution::prefer_only<boost::asio::execution::detail::outstanding_work::untracked_t<0> >, boost::asio::execution::prefer_only<boost::asio::execution::detail::relationship::fork_t<0> >, boost::asio::execution::prefer_only<boost::asio::execution::detail::relationship::continuation_t<0> > >, void>::executor_type' {aka 'class boost::asio::execution::any_executor<boost::asio::execution::context_as_t<boost::asio::execution_context&>, boost::asio::execution::detail::blocking::never_t<0>, boost::asio::execution::prefer_only<boost::asio::execution::detail::blocking::possibly_t<0> >, boost::asio::execution::prefer_only<boost::asio::execution::detail::outstanding_work::tracked_t<0> >, boost::asio::execution::prefer_only<boost::asio::execution::detail::outstanding_work::untracked_t<0> >, boost::asio::execution::prefer_only<boost::asio::execution::detail::relationship::fork_t<0> >, boost::asio::execution::prefer_only<boost::asio::execution::detail::relationship::continuation_t<0> > >'} has no member named 'defer'; did you mean 'prefer'? 194 | w.second.get_executor().defer(std::move(f), alloc2); and 3 more like this. The code doing this is in src/common/async/completion.h: void destroy_defer(std::tuple<Args...>&& args) override { auto w = std::move(work); auto f = bind_and_forward(std::move(handler), std::move(args)); RebindAlloc2 alloc2 = boost::asio::get_associated_allocator(handler); RebindTraits2::destroy(alloc2, this); RebindTraits2::deallocate(alloc2, this, 1); w.second.get_executor().defer(std::move(f), alloc2); } void destroy_dispatch(std::tuple<Args...>&& args) override { auto w = std::move(work); auto f = bind_and_forward(std::move(handler), std::move(args)); RebindAlloc2 alloc2 = boost::asio::get_associated_allocator(handler); RebindTraits2::destroy(alloc2, this); RebindTraits2::deallocate(alloc2, this, 1); w.second.get_executor().dispatch(std::move(f), alloc2); } void destroy_post(std::tuple<Args...>&& args) override { auto w = std::move(work); auto f = bind_and_forward(std::move(handler), std::move(args)); RebindAlloc2 alloc2 = boost::asio::get_associated_allocator(handler); RebindTraits2::destroy(alloc2, this); RebindTraits2::deallocate(alloc2, this, 1); w.second.get_executor().post(std::move(f), alloc2); } Has the boost API changed? If so, how to fix the above code? Thanks a lot to anyone helping me fixing this, Cheers, Thomas Goirand (zigo)

2 2

[uBlas] [Tensor] multiprecision and FFT?
by Janek Kozicki 07 Jan '21

07 Jan '21

Cem Bassoy via Boost said: (by the date of Wed, 6 Jan 2021 10:32:15 +0100) > Please consider to use and contribute to *Boost.uBlas* Hi, Does it work with boost::multiprecision types? In particular I am interested in types listed here: http://yade-dem.org/doc/HighPrecisionReal.html Does it support FFT ? In particular I am interested in replacing my very crude NDimTable class with your code: https://gitlab.com/cosurgi/trunk/-/blob/addQuantumMechanics_FixEnum_FixReba… I am about to start refactoring this part of the code, when I noticed your post. best regards Janek -- Janek Kozicki, PhD. DSc. Arch. Assoc. Prof. Gdańsk University of Technology Faculty of Applied Physics and Mathematics Department of Theoretical Physics and Quantum Information -- http://yade-dem.org/ http://pg.edu.pl/jkozicki (click English flag on top right)

2 3

C++11 on up Boost libraries
by Edward Diener 04 Jan '21

04 Jan '21

In my effort to set the meta information of 'cxxstd' for the appropriate C++11 on up libraries, my PRs for these libraries have been kindly merged to 'develop' by the library maintainers: beast callable_traits context convert coroutine2 fiber geometry gil hana histogram hof json leaf mp11 nowide outcome pfr process safe_numerics static_string stl_interfaces variant2 yap If anyone knows of any other current library which is a C++11 on up library, please tell me. My testing showed that all other Boost libraries will work in C++03 mode, but maybe I missed some other library which is a C++11 on up library. Needless to say other libraries have noted their attention to move from C++03 to C++11 in the near future. If any library does change the C++ mode necessary to use that library, I hope the maintainer(s) of that library will update the 'cxxstd' meta information appropriately. If we can get the website to work properly using the 'cxxstd' meta information, end-users should be able to know immediately whether a Boost library is usable depending on the C++ standard mode their are using.

10 20

Develop is broken on MSVC (b2 issue?)
by Antony Polukhin 04 Jan '21

04 Jan '21

I see a bunch of CI failures https://apolukhin.github.io/en/developer.html for different versions of MSVC. There are some complains on 'cl': compile-c-c++ ..\..\..\bin.v2\libs\type_index\test\track_13621.test\msvc-9.0\release\threading-multi\track_13621.obj 'cl' is not recognized as an internal or external command, operable program or batch file. call "..\..\..\bin.v2\standalone\msvc\msvc-9.0\msvc-setup.bat" amd64 >nul cl /Zm800 -nologo "track_13621.cpp" -Fo"..\..\..\bin.v2\libs\type_index\test\track_13621.test\msvc-9.0\release\threading-multi\track_13621.obj" -TP -DBOOST_TRAVISCI_BUILD /wd4675 /EHs /GR /O2 /Ob2 /W3 /MD /Zc:forScope /Zc:wchar_t /favor:blend -c -DBOOST_ALL_NO_LIB=1 -DNDEBUG "-I..\..\.." ...failed compile-c-c++ ..\..\..\bin.v2\libs\type_index\test\track_13621.test\msvc-9.0\release\threading-multi\track_13621.obj... Is that a known issue?

3 3

Regression Test Failures On develop branch
by Tom Kent 02 Jan '21

02 Jan '21

I just noticed that the develop branch has started to fail to run the develop branch, crashing early on in the run. The failures started sometime between 2020-12-31_03:52:29 PST (2020-12-31_11:52:29 UTC) (last good run) and 2020-12-31_06:57:54 PST (2020-12-31_14:57:54 UTC) (first failing run). These are still continuing with the latest develop branch. It looks like there were only a couple commits to boostorg/boost/develop in this window, and update to multiprecision (only changing meta/libraries.json) and a few changes to build. The error looks fairly non-descript... D:\teeks99-09\run\boost_root\status>"D:\teeks99-09\run\boost_bb\src\engine\bjam.exe" "-sBOOST_BUILD_PATH=D:\teeks99-09\run;D:\teeks99-09\run\boost_bb\src" "-sBOOST_ROOT=D:\teeks99-09\run\boost_root" "--boost=D:\teeks99-09\run\boost_root" "--boost-root=D:\teeks99-09\run\boost_root" "--boost-build=D:\teeks99-09\run\boost_bb\src" "--debug-configuration" -l300 toolset=msvc-11.0 -d2 preserve-test-targets=off --dump-tests -j8 address-model=64 --remove-test-targets --abbreviate-paths debug-symbols=off -m64 "--build-dir=D:\teeks99-09\run\results" 1>>"D:\teeks99-09\run\results\bjam.log" 2>&1 # Running Boost.Build tests Traceback (most recent call last): File "run.py", line 71, in <module> runner(root) File "D:\teeks99-09\run\boost_regression_src\regression.py", line 286, in __init__ self.main() File "D:\teeks99-09\run\boost_regression_src\regression.py", line 623, in main getattr(self,action_m)() File "D:\teeks99-09\run\boost_regression_src\regression.py", line 588, in command_regression self.command_test() File "D:\teeks99-09\run\boost_regression_src\regression.py", line 367, in command_test self.command_test_boost_build() File "D:\teeks99-09\run\boost_regression_src\regression.py", line 409, in command_test_boost_build "boost/bin.v2/libs/any/test/any_test.test")); WindowsError: [Error 3] The system cannot find the path specified: 'D:\\teeks99-09\\run\\results\\boost/bin.v2/libs/any/test/any_test.test\\*.*' At the end of my result-bjam.log file, I get this, but not sure if it is related. Performing configuration checks - default architecture : x86 - default address-model : 64-bit - symlinks supported : no - junctions supported : yes - hardlinks supported : yes - BOOST_COMP_GNUC >= 4.3.0 : no - has_icu builds : no - compiler supports SSE2 : yes - compiler supports SSE4.1 : yes - has synchronization.lib : yes - cxx11_constexpr : no - cxx11_decltype : yes - cxx11_hdr_tuple : no - cxx11_template_aliases : no - cxx11_variadic_templates : no - OpenCL : no - C++11 mutex : yes - has BCrypt API : yes - has stat::st_mtim : no - has stat::st_mtimensec : no - has stat::st_mtimespec : no - has stat::st_birthtim : no - has stat::st_birthtimensec : no - has stat::st_birthtimespec : no - has statx : no - has statx syscall : no - cxx11_auto_declarations : yes - cxx11_defaulted_functions : no - cxx11_final : yes - cxx11_hdr_mutex : yes - cxx11_lambdas : yes - cxx11_noexcept : no - cxx11_nullptr : yes - cxx11_rvalue_references : yes - cxx11_thread_local : no - cxx11_trailing_result_types : no warning: Graph library does not contain MPI-based parallel components. note: to enable them, add "using mpi ;" to your user-config.jam. note: to suppress this message, pass "--without-graph_parallel" to bjam. - cxx14_constexpr : no - cxx14_decltype_auto : no - cxx14_generic_lambdas : no - cxx14_return_type_deduction : no - cxx11_user_defined_literals : no - cxx11_alignas : no - iconv (libc) : no - iconv (separate) : no - icu : no - icu (lib64) : no - native atomic int32 supported : yes - has message compiler : yes - native syslog supported : no - pthread supports robust mutexes : no - compiler supports SSSE3 : yes - compiler supports AVX2 : yes warning: skipping optional Message Passing Interface (MPI) library. note: to enable MPI support, add "using mpi ;" to user-config.jam. note: to suppress this message, pass "--without-mpi" to bjam. note: otherwise, you can safely ignore this message. - cxx11_static_assert : yes - std::fstream is moveable and swappable : yes - !BOOST_COMP_GNUC : yes - BOOST_COMP_GNUC >= 6.0 : no - !BOOST_COMP_CLANG : yes - BOOST_COMP_CLANG >= 4.0 : no - cxx14_variable_templates : no - BOOST_COMP_GNUC >= 4.7.4 : no error: No best alternative for ../libs/accumulators/test/accumulators_test_valarray next alternative: required properties: <link>static <target-os>linux <toolset>clang not matched next alternative: required properties: <link>static <target-os>darwin not matched next alternative: required properties: <link>static not matched error: No best alternative for ../libs/accumulators/test/accumulators_test_tail_variate_means next alternative: required properties: <link>static <toolset-msvc:version>14.0 <toolset>msvc not matched next alternative: required properties: <link>static not matched error: No best alternative for ../libs/accumulators/test/accumulators_tests_pot_quantile_and_weighted_tail next alternative: required properties: <link>static <target-os>linux <toolset-gcc:version>4.4.7 <toolset>gcc not matched next alternative: required properties: <link>static not matched error: No best alternative for ../libs/accumulators/test/accumulators_test_weighted_tail_variate_means next alternative: required properties: <link>static <target-os>linux <toolset-gcc:version>4.4.7 <toolset>gcc not matched next alternative: required properties: <link>static <toolset-msvc:version>14.0 <toolset>msvc not matched next alternative: required properties: <link>static not matched - cxx11_constexpr : no - cxx11_decltype : yes - cxx11_hdr_tuple : no - cxx11_template_aliases : no - cxx11_variadic_templates : no - OpenCL : no - has_atomic_lib builds : no - has_pthread_lib builds : no - has_rt_lib builds : no - Clang implicit fallthrough : no - int128 : no - cpp_lib_complex_udls : no - cpp_range_based_for_17 : no - cxx11_hdr_thread : yes - cxx11_variadic_macros : yes - cxx11_hdr_unordered_set : yes - mixed_cxxstd builds : yes - mixed_cxxstd builds : yes - cxx11_hdr_array : yes - cxx11_defaulted_functions : no - cxx11_trailing_result_types : no notice: [libjpeg] Using pre-installed library notice: [libjpeg] Condition notice: [zlib] zlib is already configured notice: [libpng] Using pre-installed library notice: [libpng] Condition notice: [libtiff] Using pre-installed library notice: [libtiff] Condition - cxx14_constexpr : no - cxx14_decltype_auto : no - cxx14_generic_lambdas : no - cxx14_return_type_deduction : no - cxx11_user_defined_literals : no - Checking for gmpxx.h : no - zlib : no - bzip2 : no - lzma : no - zstd : no - lzma : no (cached) - has_lzma_cputhreads builds : no - cxx11_alignas : no - message-compiler : yes - message-compiler : yes - cxx11_unified_initialization_syntax : no - cxx11_smart_ptr : yes - GCC libquadmath and __float128 support : no - cxx11_hdr_initializer_list : no - sfinae_expr : no - cxx11_inline_namespaces : no - cxx11_range_based_for : yes - libfftw3 : no - __float128 : no - has_ntl_rr builds : no - has_mpfr_class builds : no - has_mpreal builds : no - has_e_float builds : no - gcc visibility : no - long double support : yes - cxx17_if_constexpr : no - cxx17_std_apply : no - has_eigen builds : no - Intel _Quad datatype support : no - has_mpfr builds : no - cxx11_hdr_atomic : no - cxx11_hdr_future : yes - cxx11_hdr_chrono : yes - cxx11_hdr_random : yes - cxx11_allocator : no - 128-bit floatmax_t : no - cxx11_numeric_limits : yes - cxx11_explicit_conversion_operators : no - cxx11_function_template_default_args : no - BOOST_MULTI_INDEX_KEY_SUPPORTED defined : no - has_gmp builds : no - has_tommath builds : no - has_mpfi builds : no - has_float128 builds : no - has_intel_quad builds : no - has_mpc builds : no - has_is_constant_evaluated builds : no - has_constexpr_limits builds : no - has_gmp builds : no - has_mpfr builds : no - has_big_obj builds : no - has_f2c builds : no - cxx11_noexcept : no - cxx11_rvalue_references : yes - cxx11_static_assert : yes - std::fstream is moveable and swappable : yes - cxx11_hdr_chrono : yes - !BOOST_COMP_GNUC : yes - BOOST_COMP_GNUC >= 6.0 : no - !BOOST_COMP_CLANG : yes - BOOST_COMP_CLANG >= 4.0 : no - cxx14_variable_templates : no - cxx17_structured_bindings : no - cxx17_structured_bindings : no - compiler_supports_loophole builds : yes - compiler_supports_loophole builds : yes - cxx11_hdr_unordered_map : yes WARNING: Unable to construct ../libs/predef/test/info_as_objcpp of type RUN with these properties: <abi>ms <address-model>64 <architecture>x86 <asynch-exceptions>off <bc_hdr>lib <bc_no>all_yes <binary-format>pe <boost.beast.allow-deprecated>on <boost.beast.separate-compilation>on <context-impl>fcontext <coverage>off <debug-store>object <debug-symbols>off <deduced-address-model>64 <deduced-architecture>x86 <define>BOOST_ALL_NO_LIB=1 <define>BOOST_BEAST_ALLOW_DEPRECATED <define>BOOST_BEAST_SEPARATE_COMPILATION <dependency>object(file-target)@110440 <embed-manifest-via>linker <embed-manifest>on <exception-handling>on <extern-c-nothrow>off <hardcode-dll-paths>true <host-os>windows <implicit-dependency>object(notfile-target)@92787 <include>.. <include>/D:/teeks99-09/run/boost_root/libs/predef/include <inlining>off <install-dependencies>off <link>shared <local-visibility>hidden <location-prefix>info_as_objcpp.test <midl-robust>yes <midl-stubless-proxy>yes <optimization>off <os>NT <pch>on <preserve-test-targets>off <profiling>off <python-debugging>off <python.interpreter>python <python>3.8 <relevant>define:<relevant>toolset <relevant>link:<relevant>toolset <relevant>python.interpreter:<relevant>python <relevant>python.interpreter:<relevant>target-os <relevant>threading:<relevant>runtime-link <relevant>threading:<relevant>toolset <relevant>toolset <response-file>auto <rtti>on <runtime-debugging>on <runtime-link>shared <stdlib>native <strip>off <suppress-import-lib>false <symlink-location>project-relative <tag>@Jamfile<D:\teeks99-09\run\boost_root>%Jamfile<D:\teeks99-09\run\boost_root>.tag <target-os>windows <test-info>always_show_run_output <testing.execute>on <threadapi>win32 <threading>multi <toolset-msvc:version>11.0 <toolset>msvc <user-interface>console <variant>debug <vectorize>off <visibility>hidden <warnings-as-errors>off <warnings>on <windows-api>desktop <xsl:param>boost.defaults=Boost WARNING: Considered these as possible generators: WARNING: testing.expect-success with source types { RUN_OUTPUT } and requirements { } WARNING: Unable to construct ../libs/predef/test/info_as_objc of type RUN with these properties: <abi>ms <address-model>64 <architecture>x86 <asynch-exceptions>off <bc_hdr>lib <bc_no>all_yes <binary-format>pe <boost.beast.allow-deprecated>on <boost.beast.separate-compilation>on <context-impl>fcontext <coverage>off <debug-store>object <debug-symbols>off <deduced-address-model>64 <deduced-architecture>x86 <define>BOOST_ALL_NO_LIB=1 <define>BOOST_BEAST_ALLOW_DEPRECATED <define>BOOST_BEAST_SEPARATE_COMPILATION <dependency>object(file-target)@110440 <embed-manifest-via>linker <embed-manifest>on <exception-handling>on <extern-c-nothrow>off <hardcode-dll-paths>true <host-os>windows <implicit-dependency>object(notfile-target)@92787 <include>.. <include>/D:/teeks99-09/run/boost_root/libs/predef/include <inlining>off <install-dependencies>off <link>shared <local-visibility>hidden <location-prefix>info_as_objc.test <midl-robust>yes <midl-stubless-proxy>yes <optimization>off <os>NT <pch>on <preserve-test-targets>off <profiling>off <python-debugging>off <python.interpreter>python <python>3.8 <relevant>define:<relevant>toolset <relevant>link:<relevant>toolset <relevant>python.interpreter:<relevant>python <relevant>python.interpreter:<relevant>target-os <relevant>threading:<relevant>runtime-link <relevant>threading:<relevant>toolset <relevant>toolset <response-file>auto <rtti>on <runtime-debugging>on <runtime-link>shared <stdlib>native <strip>off <suppress-import-lib>false <symlink-location>project-relative <tag>@Jamfile<D:\teeks99-09\run\boost_root>%Jamfile<D:\teeks99-09\run\boost_root>.tag <target-os>windows <test-info>always_show_run_output <testing.execute>on <threadapi>win32 <threading>multi <toolset-msvc:version>11.0 <toolset>msvc <user-interface>console <variant>debug <vectorize>off <visibility>hidden <warnings-as-errors>off <warnings>on <windows-api>desktop <xsl:param>boost.defaults=Boost WARNING: Considered these as possible generators: WARNING: testing.expect-success with source types { RUN_OUTPUT } and requirements { } - BOOST_OS_MACOS : no - BOOST_COMP_CLANG > 0.0.0 : no - BOOST_OS_LINUX == 0 : yes WARNING: Unable to construct ../libs/predef/test/info_as_objcpp of type RUN with these properties: <abi>ms <address-model>64 <architecture>x86 <asynch-exceptions>off <bc_hdr>lib <bc_no>all_yes <binary-format>pe <boost.beast.allow-deprecated>on <boost.beast.separate-compilation>on <context-impl>fcontext <coverage>off <debug-store>object <debug-symbols>off <deduced-address-model>64 <deduced-architecture>x86 <define>BOOST_ALL_NO_LIB=1 <define>BOOST_BEAST_ALLOW_DEPRECATED <define>BOOST_BEAST_SEPARATE_COMPILATION <dependency>object(file-target)@110440 <embed-manifest-via>linker <embed-manifest>on <exception-handling>on <extern-c-nothrow>off <hardcode-dll-paths>true <host-os>windows <implicit-dependency>object(notfile-target)@92787 <include>.. <include>/D:/teeks99-09/run/boost_root/libs/predef/include <inlining>off <install-dependencies>off <link>shared <local-visibility>hidden <location-prefix>info_as_objcpp.test <midl-robust>yes <midl-stubless-proxy>yes <optimization>off <os>NT <pch>on <preserve-test-targets>off <profiling>off <python-debugging>off <python.interpreter>python <python>3.8 <relevant>define:<relevant>toolset <relevant>link:<relevant>toolset <relevant>python.interpreter:<relevant>python <relevant>python.interpreter:<relevant>target-os <relevant>threading:<relevant>runtime-link <relevant>threading:<relevant>toolset <relevant>toolset <response-file>auto <rtti>on <runtime-debugging>on <runtime-link>shared <stdlib>native <strip>off <suppress-import-lib>false <symlink-location>project-relative <tag>@Jamfile<D:\teeks99-09\run\boost_root>%Jamfile<D:\teeks99-09\run\boost_root>.tag <target-os>windows <test-info>always_show_run_output <testing.execute>on <threadapi>win32 <threading>multi <toolset-msvc:version>11.0 <toolset>msvc <user-interface>console <variant>debug <vectorize>off <visibility>hidden <warnings-as-errors>off <warnings>on <windows-api>desktop <xsl:param>boost.defaults=Boost WARNING: Considered these as possible generators: WARNING: testing.expect-success with source types { RUN_OUTPUT } and requirements { } WARNING: Unable to construct ../libs/predef/test/info_as_objc of type RUN with these properties: <abi>ms <address-model>64 <architecture>x86 <asynch-exceptions>off <bc_hdr>lib <bc_no>all_yes <binary-format>pe <boost.beast.allow-deprecated>on <boost.beast.separate-compilation>on <context-impl>fcontext <coverage>off <debug-store>object <debug-symbols>off <deduced-address-model>64 <deduced-architecture>x86 <define>BOOST_ALL_NO_LIB=1 <define>BOOST_BEAST_ALLOW_DEPRECATED <define>BOOST_BEAST_SEPARATE_COMPILATION <dependency>object(file-target)@110440 <embed-manifest-via>linker <embed-manifest>on <exception-handling>on <extern-c-nothrow>off <hardcode-dll-paths>true <host-os>windows <implicit-dependency>object(notfile-target)@92787 <include>.. <include>/D:/teeks99-09/run/boost_root/libs/predef/include <inlining>off <install-dependencies>off <link>shared <local-visibility>hidden <location-prefix>info_as_objc.test <midl-robust>yes <midl-stubless-proxy>yes <optimization>off <os>NT <pch>on <preserve-test-targets>off <profiling>off <python-debugging>off <python.interpreter>python <python>3.8 <relevant>define:<relevant>toolset <relevant>link:<relevant>toolset <relevant>python.interpreter:<relevant>python <relevant>python.interpreter:<relevant>target-os <relevant>threading:<relevant>runtime-link <relevant>threading:<relevant>toolset <relevant>toolset <response-file>auto <rtti>on <runtime-debugging>on <runtime-link>shared <stdlib>native <strip>off <suppress-import-lib>false <symlink-location>project-relative <tag>@Jamfile<D:\teeks99-09\run\boost_root>%Jamfile<D:\teeks99-09\run\boost_root>.tag <target-os>windows <test-info>always_show_run_output <testing.execute>on <threadapi>win32 <threading>multi <toolset-msvc:version>11.0 <toolset>msvc <user-interface>console <variant>debug <vectorize>off <visibility>hidden <warnings-as-errors>off <warnings>on <windows-api>desktop <xsl:param>boost.defaults=Boost WARNING: Considered these as possible generators: WARNING: testing.expect-success with source types { RUN_OUTPUT } and requirements { } - zlib : no (cached) - bzip2 : no (cached) - lzma : no (cached) - zstd : no (cached) - zlib : no - bzip2 : no - lzma : no - zstd : no - auto_ptr : yes - cxx11_lambdas : yes - std_wstreambuf : yes - cxx11_hdr_forward_list : yes Happy new year! Tom

2 2

Re: [boost] Boost website changes and .'cxxstd`
by Donovan Dikaio 30 Dec '20

30 Dec '20

Hi Edward, you're right. The beta website link is https://beta.boost.org/ FYI, there is a file 'libraries.txt' in the source codes which contains all the libraries info. It looks like that it can be generated by a site tool. To my codes review, there exist multiple records for a library for various versions in the above text file. And the codes check and compare a library record’s version info with the current version, and pick one matching a condition. There is no record with 'cxxstd' field at the text file for beta website but for main site. Unfortunately, there is no one to match version comparison condition for main site as well at the moment. The updates codes of beta website will only show 'C++ standard minimum level' with 'cxxstd' value only if a 'cxxstd' value exists.

2 1

Potential order statistic tree?
by Soronel Haetir 29 Dec '20

29 Dec '20

Boost developers, Would there be interest in adding an order statistic tree to the boost library? That is, a tree that instead of being sorted simply keeps nodes in whatever order is specified, along with a (potentially multi-index) per-node value and a total of per-node values of each node and its left-descent tree. I currently have two such types, a very capable intrusive version (not based on boost::intrusive though using some of the same ideas) and a less capable non-intrusive form that uses the mechanics of the intrusive form as an implementation detail. The reason for not being based on Boost.Intrusive is that the tree algorithms that Boost.Intrusive provides are all for search trees and this very definitely is not, plus the need to alter node weights during insert, delete and rotations and the Boost.Intrusive algorithm providers not having a good place to add that behavior. I have personally found this type very useful while implementing a rope container and also while implementing tracking for various parts of a text editor (that is, paragraph, line and run positions) (in terms of characters, graphemes and screen height). Perhaps the major drawback to what I have is that I have not been careful to isolate c++-version dependent code. Although I know it does compile with the latest msvc 2019 as well as the clang 10.0 that MS ships. I am simply not sure whether such a type has a broad enough appeal to make the work of adding it to boost worthwhile. -- Soronel Haetir soronel.haetir(a)gmail.com

4 3

Boost website changes and .'cxxstd'
by Edward Diener 24 Dec '20

24 Dec '20

Even though I have worked a little with PHP in the past I do not have the talent to make the change to the website which would incorporate the addition of the meta information json field 'cxxstd' to the Boost documentation web page for each library. The idea is that if 'cxxstd' is set to a value the documentation for that library would also show: C++ standard minimum level: C++nn where nn would be 11, 14, 17, or 20 depending on the value of 'cxxstd'. Alternatively if there is no 'cxxstd' entry for a library or if the value of 'cxxstd' is '03', we could either specify 'nn' as '03' or leave off the line stating the 'C++ standard minimum level completely. On the face of it this should be doable in the website code but evidently Daniel James is the only one who really understands how this works in the code and he is no longer active in Boost. So if someone else who understands the website code and PHP could do this it would be appreciated, since I think it will be valuable telling end-users whether a Boost library is usable at the C++ compiler level they are using.

3 3

(no subject)
by Harsh 21 Dec '20

21 Dec '20

Respected Sir/Madam Myself Harsh Agarwal a highly interested candidate to work on with ublas as a open source contributor but at starting need some guidance-: 1-:How can i start on with it. 2-: As if i want to participate in Gsoc 2021 till when will i get competency test. 3-: can i know about the basic project idea that will be for gsoc 2021 thanking you Harsh Agarwal 21/12/2020

2 1

regarding boost gsoc competency test 2021
by Mohd Huzaifa 20 Dec '20

20 Dec '20

hii sir/madam I want to ask about the boost competency test for gsoc 2021. When it will be available. And can I get the list of past competency tests.

2 1

Tagging the minimum C++ standard level for Boost libs
by Edward Diener 19 Dec '20

19 Dec '20

I had previously proposed that we tag the minimum C++ standard level for Boost libs by adding information to the json meta information in libraries.json for each library. I would like to revisit that proposal, which involved more elaborate suggestions, with this simpler overall proposal: for each Boost C++ library whose minimum C++ standard level is C++11 or above we add a json field called 'cxxstd' whose value corresponds to one of the same values as currently exists in Boost.Build for the 'cxxstd' feature, ie. 11,14,17,20, to the libraries.json file for that library. This json value can then be used in Boost documentation of each library to specify the minimum C++ standard level needed by an end-user in order to use that library. Obviously we can also add "cxxstd": "03" for the many Boost libraries which can still be used at the C++98/C++03 compilation level also, even though I would argue that not having a "cxxstd" json field should mean C++98/C++03 by default. I would be willing to create the necessary PRs for each library, as I have a pretty good internal list of this information. The gist of this proposal is to make it much easier for end-users wishing to use a Boost library to immediately know whether the library they wish to use is usable at the C++ standard compilation level they are using for compilation, without having to spend time searching for such information, which is often not readily available, in the documentation of the library they are considering. I can go ahead and start doing this now, but of course I am willing to listen to what others think about this. But let's not let another round of inertia stop doing at all what should be a simple means of telling end-user's whether a Boost library is at least minimally usable by them in their C++ projects.

5 13

Re: [boost] [release] Boost 1.75.0 Release Candidate 1
by Glen Fernandes 17 Dec '20

17 Dec '20

On 2020-12-13 03:34:00 Glen Fernandes wrote: > > On Sat, Dec 12, 2020 at 8:16 PM Edward Diener wrote: >> The final issue was that the index.html for the release showed 1.74 >> rather than 1.75. This seems to be generated from some sort of template >> where '{{version}}' is supposed to be plugged in by the correct version, >> but evidently did not work properly. Maybe someone who knows how this is >> supposed to work, but evidently did not, can look at it. > > Sounds like generate.php?page=index.html&version=<version> was invoked > with the wrong <version> . I'll take a look and see what I can find. Fixed: https://github.com/boostorg/release-tools/commit/b08dbc34451e9f5b09ec44cab5… Glen

1 0

Boost Pub/Sub message service model Implementation
by Rakshita Parihar 15 Dec '20

15 Dec '20

Hello, Currently, I am working on an IoT project where I need to send data from client to server. To transfer data, I need to setup a Pub/Sub message service model. Presently, I am using MQTT Paho C libraries to transmit data to server over TCP IP protocol but I want to switch to boost C++ library for the publish/subscribe model. I am a newbie to this library and have some queries: *1) Is there any boost C++ library for pub/sub model? If yes, please give me the details or link for the tutorial.* *2) If no library is present, please tell me how to implement a message pub/sub <https://en.wikipedia.org/wiki/Publish%E2%80%93subscribe_pattern> service to communicate using boost C++ library?* Please, help me to solve these issues. Thanks & Regards, Rakshita Parihar

5 5

[release] Boost 1.75.0 Release Candidate 1
by Marshall Clow 13 Dec '20

13 Dec '20

[release] Boost 1.75.0 Release Candidate 1 The first release candidates for the 1.75.0 release are now available at: <https://dl.bintray.com/boostorg/release/1.75.0/source/> The SHA256 checksums are as follows: caf36d7c13b3d8ce62282a64a695113945a13b0f1796a45160726d04295f95ed boost_1_75_0_rc1.zip aeb26f80e80945e82ee93e5939baebdca47b9dee80a07d3144be1e1a6a66dd6a boost_1_75_0_rc1.tar.gz 953db31e016db7bb207f11432bef7df100516eeb746843fa0486a222e3fd49cb boost_1_75_0_rc1.tar.bz2 3a8b314871646e7404886736273c053278ba71b11347f72d4751411d65d6d1a5 boost_1_75_0_rc1.7z As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. -- The Release managers

6 11

bootstrap was broken since 1.74
by Neo Anderson 12 Dec '20

12 Dec '20

Hi List, I am a casual user of boost library. I usually build boost for use to build CodeBlocks IDE on Windows platform. But since version 1.74, I found that bootstrap.bat was broken. So I skipped 1.74 and stuck to the old version 1.73. Today I am happy to see that 1.75 was out and I thought this problem would have been fixed since it’s a small problem. But I am wrong. I think line 15 lacks command line parameter: call .\build.bat %1. After adding that %1, I successfully built b2 with bootstrap.cmd gcc. But when I run .\b2, I get very confusing error messages (which are the same ones in 1.74): C:\Build\src\boost_1_75_0>.\b2 Performing configuration checks - default address-model : 32-bit - default architecture : x86 Building the Boost C++ Libraries. - compiler supports SSE2 : yes - compiler supports SSE4.1 : yes - has synchronization.lib : yes - C++11 mutex : yes - has BCrypt API : yes - has stat::st_mtim : no - has stat::st_mtimensec : no - has stat::st_mtimespec : no - has stat::st_birthtim : no - has stat::st_birthtimensec : no - has stat::st_birthtimespec : no - has statx : no - has statx syscall : no - cxx11_auto_declarations : yes - cxx11_constexpr : yes - cxx11_defaulted_functions : yes - cxx11_final : yes - cxx11_hdr_mutex : yes - cxx11_hdr_tuple : yes - cxx11_lambdas : yes - cxx11_noexcept : yes - cxx11_nullptr : yes - cxx11_rvalue_references : yes - cxx11_template_aliases : yes - cxx11_thread_local : no - cxx11_variadic_templates : yes - has_icu builds : no warning: Graph library does not contain MPI-based parallel components. note: to enable them, add "using mpi ;" to your user-config.jam. note: to suppress this message, pass "--without-graph_parallel" to bjam. - zlib : yes - bzip2 : no - lzma : no - zstd : yes - lzma : no - has_lzma_cputhreads builds : no - cxx11_alignas : yes - cxx11_decltype : yes - iconv (libc) : no - iconv (separate) : yes - icu : no - icu (lib64) : no - native atomic int32 supported : yes - has message compiler : no - native syslog supported : no - pthread supports robust mutexes : no - compiler supports SSSE3 : yes - compiler supports AVX2 : yes - gcc visibility : yes - long double support : yes warning: skipping optional Message Passing Interface (MPI) library. note: to enable MPI support, add "using mpi ;" to user-config.jam. note: to suppress this message, pass "--without-mpi" to bjam. note: otherwise, you can safely ignore this message. - cxx11_static_assert : yes - std::fstream is moveable and swappable : yes - Has Large File Support : yes warning: No python installation configured and autoconfiguration note: failed. See http://www.boost.org/libs/python/doc/building.html note: for configuration instructions or pass --without-python to note: suppress this message and silently skip all Boost.Python targets - libbacktrace builds : no - addr2line builds : no - WinDbg builds : yes - WinDbgCached builds : no - BOOST_COMP_GNUC >= 4.3.0 : yes - zlib : yes (cached) - bzip2 : no (cached) - lzma : no (cached) - zstd : yes (cached) - compiler supports SSE2 : no - compiler supports SSE4.1 : no - has synchronization.lib : no - C++11 mutex : no - has BCrypt API : no - is Windows CE : no - has stat::st_mtim : no - has stat::st_mtimensec : no - has stat::st_mtimespec : no - has stat::st_birthtim : no - has stat::st_birthtimensec : no - has stat::st_birthtimespec : no - has statx : no - has statx syscall : no - cxx11_auto_declarations : no - cxx11_constexpr : no - cxx11_defaulted_functions : no - cxx11_final : no - cxx11_hdr_mutex : no - cxx11_hdr_tuple : no - cxx11_lambdas : no - cxx11_noexcept : no - cxx11_nullptr : no - cxx11_rvalue_references : no - cxx11_template_aliases : no - cxx11_thread_local : no - cxx11_variadic_templates : no - native atomic int32 supported : no - has message compiler : no - native syslog supported : no - pthread supports robust mutexes : no - has_icu builds : no - compiler supports SSSE3 : no - compiler supports AVX2 : no C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:609: in start-building from module targe ts error: Recursion in main target references error: the following target are being built currently: error: ./forward ./stage ./stage-proper libs/filesystem/build/stage libs/filesystem/build/stage-depe ndencies libs/log/build/stage libs/log/build/stage-dependencies libs/filesystem/build/stage C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:776: in class(a)main-target.generate from module object(main-target)@7282 C:/Build/src/boost_1_75_0/tools/boost_install\boost-install.jam:1176: in generate-dependencies from module boost-install C:/Build/src/boost_1_75_0/tools/build/src/kernel\modules.jam:107: in modules.call-in from module boo st-install C:/Build/src/boost_1_75_0/tools/build/src/util\indirect.jam:105: in indirect.call from module indire ct C:/Build/src/boost_1_75_0/tools/build/src/tools\generate.jam:59: in construct from module object(gen erated-target-class)@2809 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:1364: in class(a)basic-target.generate fro m module object(generated-target-class)@2809 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:812: in generate-really from module obje ct(main-target)@11221 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:784: in class(a)main-target.generate from module object(main-target)@11221 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:934: in targets.generate-from-reference from module targets C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:1277: in generate-dependencies from modu le object(alias-target-class)@2810 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:1334: in class(a)basic-target.generate fro m module object(alias-target-class)@2810 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:812: in generate-really from module obje ct(main-target)@11222 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:784: in class(a)main-target.generate from module object(main-target)@11222 C:/Build/src/boost_1_75_0/tools/boost_install\boost-install.jam:1176: in generate-dependencies from module boost-install C:/Build/src/boost_1_75_0/tools/build/src/kernel\modules.jam:107: in modules.call-in from module boo st-install C:/Build/src/boost_1_75_0/tools/build/src/util\indirect.jam:105: in indirect.call from module indire ct C:/Build/src/boost_1_75_0/tools/build/src/tools\generate.jam:59: in construct from module object(gen erated-target-class)@1817 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:1364: in class(a)basic-target.generate fro m module object(generated-target-class)@1817 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:812: in generate-really from module obje ct(main-target)@7281 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:784: in class(a)main-target.generate from module object(main-target)@7281 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:934: in targets.generate-from-reference from module targets C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:1277: in generate-dependencies from modu le object(alias-target-class)@1818 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:1334: in class(a)basic-target.generate fro m module object(alias-target-class)@1818 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:812: in generate-really from module obje ct(main-target)@7282 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:784: in class(a)main-target.generate from module object(main-target)@7282 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:934: in targets.generate-from-reference from module targets C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:1277: in generate-dependencies from modu le object(alias-target-class)@184 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:1334: in class(a)basic-target.generate fro m module object(alias-target-class)@184 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:812: in generate-really from module obje ct(main-target)@5196 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:784: in class(a)main-target.generate from module object(main-target)@5196 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:934: in targets.generate-from-reference from module targets C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:1277: in generate-dependencies from modu le object(top-level-target)@190 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:1334: in alias-target-class.generate fro m module object(top-level-target)@190 C:/Build/src/boost_1_75_0\boostcpp.jam:403: in build-multiple from module object(top-level-target)@1 90 C:/Build/src/boost_1_75_0\boostcpp.jam:393: in class(a)top-level-target.generate from module object(to p-level-target)@190 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:812: in generate-really from module obje ct(main-target)@5198 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:784: in class(a)main-target.generate from module object(main-target)@5198 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:934: in targets.generate-from-reference from module targets C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:1277: in generate-dependencies from modu le object(top-level-target)@191 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:1334: in alias-target-class.generate fro m module object(top-level-target)@191 C:/Build/src/boost_1_75_0\boostcpp.jam:403: in build-multiple from module object(top-level-target)@1 91 C:/Build/src/boost_1_75_0\boostcpp.jam:393: in class(a)top-level-target.generate from module object(to p-level-target)@191 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:812: in generate-really from module obje ct(main-target)@5199 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:784: in class(a)main-target.generate from module object(main-target)@5199 C:/Build/src/boost_1_75_0/tools/build/src/build\targets.jam:273: in class(a)project-target.generate fr om module object(project-target)@134 C:/Build/src/boost_1_75_0/tools/build/src\build-system.jam:797: in load from module build-system C:/Build/src/boost_1_75_0/tools/build/src/kernel\modules.jam:295: in import from module modules C:/Build/src/boost_1_75_0/tools/build/src/kernel/bootstrap.jam:139: in boost-build from module C:/Build/src/boost_1_75_0/boost-build.jam:17: in module scope from module

1 0

[release] Boost 1.75.0
by Marshall Clow 11 Dec '20

11 Dec '20

Release 1.54.0 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 1 new library and numerous enhancements and bug fixes for existing libraries. For details, including download links, see <http://www.boost.org/users/news/version_1.75.0> You can also download directly from: <https://dl.bintray.com/boostorg/release/1.75.0/> To install this release on your system, see <http://www.boost.org/doc/libs/release/more/getting_started/index.html> Thanks to everyone who participated in this release. Thanks, -- The Boost Release Team Marshall Clow, Glen Fernandes, Michael Caisse

2 1

[release] 1.76.0 open for merging
by Marshall Clow 11 Dec '20

11 Dec '20

The master branch is open for merging all stable changes from develop, 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 <http://www.boost.org/development/index.html> Release schedule explanation: https://github.com/boostorg/wiki/wiki/Releases%3A-Schedule <https://github.com/boostorg/wiki/wiki/Releases%3A-Schedule> Release practices for developers: http://svn.boost.org/trac/boost/wiki/ImprovingPractices <http://svn.boost.org/trac/boost/wiki/ImprovingPractices> -- The Boost Release Team

2 1

The new Boost 17.0.0
by Antony Polukhin 10 Dec '20

10 Dec '20

Hi, == The problem. TL;DR: we are having huge troubles with usability and popularity! Quite a lot of companies forbid using Boost because: * it provides vocabulary types, that should be the same across the whole project (like shared_ptr, filesystem::path or optional). Otherwise it's hard to combine different APIs * it is huge, in consists of legacy on more than a half, with a lot of dependencies between libraries. This is extremely painful for big companies, because there's no efficient distributed build system. Each company invents it's own and/or tries to minimize headers by all means. New companies (startups) also avoid Boost: * "We are using C++17, we do not want legacy libraries with C++98 support" * Junior developers are confused by multiple vocabulary types. "Should we use boost::optional or std::optional?" * hard to upgrade, because symbols are not versioned ISO C++ WG21 community not willing to push prototypes into Boost. "We aim to establish "existing practice" and provide reference implementations so that Boost libraries are suitable for eventual standardization." - that's not really true any more. == The Solution TL;DR: we need a C++17 fork of Boost with close to 0 dependencies between libraries and namespace versioning. С++17 provides many vocabulary types, feature test macro and a bunch of features for variadic templates. All of that allows us to drop a lot of weight and fix majority of popularity and usability problems. Rule of a thumb should be: "If the C++17 provides that functionality - use the standard version". That approach would allow to loose a lot of weight, do not mess with vocabulary types and significantly reduce dependencies https://pdimov.github.io/boostdep-report/master/module-levels.html By levels: config 0 -> we probably would not need it any more assert 1 -> 0 core 2 -> 1 (or 0 if we merge it with asser) smart_ptr 4 -> 2 exception 5 -> 2 stacktrace 5 -> 2 intrusive 5 -> 2 outcome 6 -> 3 container 6 -> 3 gil 11 -> 2? context 16 -> 2? dll 17 -> 1 asio 18 -> 3? beast 19 -> 4? == The Path TL;DR: we should start the Boost17 now and ship it as we are ready. Old Boost should be still available. The new approach requires quite a lot of effort and not all the maintainers have enough time to do the migration. We should keep releasing the existing Boost, while migrating the libraries to the Boost17. The migration is not as hard as it seems. It took 2 or 3 days to make Boost.DLL work with either boost or std filesystem. It could be done in less than a day, if I do not have to support the Boost filesystem. == Action points 0) Discuss 1) Bury the idea, wait for a few years, goto 0); or make a boost17 repo with the same layout as the existing one, but without submodules 2) start the migration -- Best regards, Antony Polukhin

28 120

[release] Master branch now closed for 1.75.0 release
by Marshall Clow 09 Dec '20

09 Dec '20

3 5

qvm: return type for mixed scalar type vector operations
by Kai Szuttor 09 Dec '20

09 Dec '20

Hey all, concerning vector operations in boost qvm, is it possible to somehow specify the return type of a binary operator with mixed scalar input data, e.g. operator+(vec<double, 3>, vec<int, 3>) ? Could not find the customisation point to do this depending on the involved operation. Thanks in advance, Kai

2 2

Re: [boost] Boost Digest, Vol 6513, Issue 3
by Brian Wood 07 Dec '20

07 Dec '20

Peter Dimov writes: > Marshall Clow wrote: > > > I must concur with Ville here; I have had several people tell me they > won?t > > use Boost because ?it changes with every release?. > > Boost does change with every release, and I still keep using 1.38 in > several > projects of mine, but these changes are not limited to ABI at all. > Everything changes, you have to retest the whole lot, for correctness as > well as performance. > > And in general, expecting ABI stability from a collection of predominantly > header-only libraries is setting one up for severe disappointment. > > The standardized libraries are more header-only than Boost so am not sure how this isn't a rap on them also. Somehow C++ has become successful in spite of this. Brian Ebenezer Enterprises - In G-d we trust. https://github.com/Ebenezer-group/onwards

3 2

[SmartPtr] intrusive_ref_counter CounterPolicyT requirements API?
by Billy 05 Dec '20

05 Dec '20

Hi Boost, We're considering implementing our own atomic ref count for `intrusive_ref_count` [*]. A question came up. Is the `CounterPolicyT` template parameter a stable extension hook, or are users expected to strictly stick to the two provided policies of `thread_unsafe_counter` and `thread_safe_counter`? I can see that under the hood, these policy structs are trivially simple and we can just do it, but the question is really about whether the lack of documentation implies that it's a private boost detail. From https://www.boost.org/doc/libs/1_74_0/libs/smart_ptr/doc/html/smart_ptr.htm… "The second parameter is a policy that defines the nature of the reference counter. The library provides two such policies: thread_unsafe_counter and thread_safe_counter." Thanks for your time, Billy Donahue [*] Incidentally we want to increment with memory order relaxed instead of acq_rel. -- ǝnɥɐuop ʎllıq

3 4

CONTRIBUTION TOWARD YOUR OPEN SOURCE COMMUNITY.
by Prakash Choure 03 Dec '20

03 Dec '20

Hii sir/mam I am Prakash Choure and i want to contribute my skill to your open source organisation . As i am a beginner can you guide me for contribution toward your organization .My knowledge is "C" , "C++" And basic of Data structure and Algorithm . please can your team guide me. Thank you

3 2

[release] 1.75.0 post-beta merges
by Marshall Clow 02 Dec '20

02 Dec '20

The master branch is is now open for post-beta merges, but only as described in the Post-Beta Merge Policy. See <https://github.com/boostorg/wiki/wiki/Releases%3A-Beta-Merge-Policy> Reminder: The master branch closes for the release on December 2nd. Full calendar here: https://www.boost.org/development/ -- The release managers

10 47

PolyCollection
by Brian Wood 30 Nov '20

30 Nov '20

Shalom Hey, is anyone using PolyCollection? I have serialization support for it: https://github.com/Ebenezer-group/onwards/tree/master/example/poly If you considered it, but chose an alternative library, what was the reason? Thanks. Brian Ebenezer Enterprises - Enjoying programming again. https://webEbenezer.net

1 0

[release] Issues
by Glen Fernandes 30 Nov '20

30 Nov '20

Need resolution: * Boost.Utility's <boost/operators.hpp> and C++20 * Boost.uBLAS tests failing C++03 and C++14. (They were failing C++20 but I cherry-picked the allocator fixes from develop, so these pass now) Glen

2 1

Re: [boost] The new Boost 17.0.0
by Glen Fernandes 29 Nov '20

29 Nov '20

On 2020-11-29, Raffi Enficiaud wrote: > 0/ For the discussions I am all for it, but I would absolutely not try > to gather consensus. Because there won't be. You definitely don't need consensus. You are free to drop C++03 and C++11 and C++14 support from Boost.Test whenever you want. We've been steadily migrating Boost libraries away from using Boost.Test to using Boost.LightweightTest for various reasons. (And have plans to migrate a few more to Boost.LightweightTest by Boost 1.76) So you can decide to require C++17 or higher for Boost.Test and not have to worry about other Boost libraries. We'll make sure their tests are still working by moving them to LWT. Just give us some warning, before you drop any support. :) Glen

1 0

Re: [boost] The new Boost 17.0.0
by Glen Fernandes 27 Nov '20

27 Nov '20

Dominique Devienne wrote: > > Glen Fernandes wrote >> I would not be in favor of a Boost distribution that requires anything >> higher than C++11 for existing libraries. i.e. Not C++17 or even >> C++14. > > But that's basically Boost as it stands, i.e. Boost 1.x. > I don't think anyone's proposing to drop that. That's Boost 1.x with more C++11 and less C++03 - with authors who choose to drop C++03 support, requiring C++11 at a minimum as per: https://pdimov.github.io/articles/phasing_out_cxx03.html This is something which Boost authors are actually acting on. e.g. Boost.Math and Boost.Multiprecision as of a future Boost 1.77 release: https://www.boost.org/users/history/version_1_73_0.html <quote> Math * IMPORTANT: C++03 support is now deprecated and will be removed from March 2021. </quote> <quote> Multiprecision * IMPORTANT: C++03 support is now deprecated and will be removed from March 2021. </quote> i.e. This is promising because people support this particular proposal enough to do something, not just for the (potentially unlimited) joy of discussing it on a list. > But isn't this just a "teething" issue? I see Ville already replied in fact. I'm following this discussion over this in C++ committee EWG reflector. I'm optimistic that people will do the right thing by users. But I prefer to make decisions based on what I know now, and what has bitten users today, with -std=c++20 and GCC 10.1 that has already shipped, not speculation about what will happen. As I said before, this is just me. C++11 (not higher, not C++17 or C++20) is just what I support and what I'd be willing to put in work towards in existing Boost libraries (and even volunteer to do for those that I do not currently maintain, but would welcome the contributions). Other authors remain free to drop support for everything besides C++17 or C++20 if they want. Glen

1 1

Re: [boost] The new Boost 17.0.0
by Glen Fernandes 27 Nov '20

27 Nov '20

Speaking only for myself as an author of a Boost library, maintainer of many Boost libraries, and contributor to many Boost libraries, as well as being involved in the Boost release process: 1. Based on my personal knowledge of Boost users, as well as e-mails to the Boost developers lists (boost@...), and the Boost Owners lists (boost-owner@...) from users such as: - @us.af.mil (US Airforce) - @nasa.gov (NASA) and others I would not be in favor of a Boost distribution that requires anything higher than C++11 for existing libraries. i.e. Not C++17 or even C++14. 2. Based on first hand accounts of certain users choosing not to migrate to C++20 because of a silently breaking change in the language affecting their code (operator== rewriting rules, which has even broken certain Boost libraries like Rational), I would certainly not be in favor of changing existing Boost libraries to require C++20 for anything in an official Boost distribution. Glen

4 3

Re: [boost] [release] 1.75.0 post-beta merges
by Peter Dimov 26 Nov '20

26 Nov '20

>>>> ...failed testing.capture-output >>>> ..\..\bin.v2\libs\filesystem\test\operations_unit_test.test\clang-win-10.0.0\release\threading-multi\operations_unit_test.run... ... > This looks like a Clang x86 codegen bug. The compiler returns the > `file_status` from `get_status` on the stack and then overwrites it with > `push` instructions for some reason. > > Not the first x86 clang-cl problem. I'll upgrade from 10.0 to 11.0 to see > if it's fixed. Still not fixed in 11.0.

2 3

[random] Merging to master for 1.75 release
by Edward Diener 25 Nov '20

25 Nov '20

Is there any possibility of merging 'develop' to 'master' for the random library for the 1.75 release ? The 'master' branch has not been updated for 2 years, or since the 1.70 release. While I am not claiming all invaluable fixes I know my fix for Embarcadero C++ clang-based support and another fix for correctly auto-linking random_device is among the 'develop' branch fixes which have never made it to the 'master' branch.

4 9

Submitting release notes
by Andrzej Krzemienski 25 Nov '20

25 Nov '20

I am sorry for this silly question, but can someone remind me, where we file PR-s with library release notes? Can someone point me to the place where this is documented? Regards, &rzej;

2 1

[leaf] Request to merge bug fix to master for 1.75 release
by Emil Dotchevski 24 Nov '20

24 Nov '20

I'm requesting permission to merge a bug fix by vector-of-bool in LEAF which makes it work correctly with std::system_error: https://github.com/boostorg/leaf/pull/15/commits/efc56d1c703777fea4fef2bd24… (There is a minor related change on top of this PR, but this bug fix is the important change in behavior. Note that LEAF is a new library in 1.75).

2 1

[release] Boost 1.75.0 Beta 1 Release Candidate 2
by Marshall Clow 17 Nov '20

17 Nov '20

The second release candidates for the 1.75.0 beta release are now available at: <https://dl.bintray.com/boostorg/beta/1.75.0.beta1/source/> The SHA256 checksums are as follows: 3f01d3e5dc822e151892040d4667e364ea808d208d2e49cc7a1802bd4da3d4cc boost_1_75_0_b1_rc2.7z 9b75a80f845d4ae312e3c9151ffdfe3fed450973095e0a15c68d0be394f2f2df boost_1_75_0_b1_rc2.tar.bz2 123519d4b056fbbd69e452db880abe2c7e55f21779d44a4d6b6c714d5c13c3ee boost_1_75_0_b1_rc2.tar.gz b73e01d22d5b3d2ff82f14a371e3974fab30448bf6ff5ac8b9c829539a19c2d7 boost_1_75_0_b1_rc2.zip As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. -- The Release managers

9 23

[release] Fixing Boost.Rational and boost/operators.hpp infinite loop in C++20 by 1.75
by Glen Fernandes 16 Nov '20

16 Nov '20

We have a problem with Boost.Rational and <boost/operators.hpp> in Boost.Utility in C++20 standards mode. I've fixed Boost.Rational in develop. Relevant GitHub issues: 1. https://github.com/boostorg/rational/issues/43 2. https://github.com/boostorg/utility/issues/65 My fix for Boost.Rational that I will merge to master for the 1.75 release: https://github.com/boostorg/rational/pull/45 The root cause is the same. C++20 adds new language rules that implicitly generate some operators, and the current implementations result in an infinite loop. (In both cases an equality operator ends up calling itself recursively). GCC does emit a warning diagnostic in C++20 mode, but as usual these tend to be unnoticed at build time. ../../boost/rational.hpp:779:16: warning: in C++20 this comparison calls the current function recursively with reversed arguments 779 | return a == b; | ~~^~~~ So this issue was found by three independent users of Rational (one who reported a Github issue, the other who complained on Reddit, and a third that tried running the Rational unit tests with GCC10 and found two failures). <boost/operators.hpp> in Boost.Utility still needs a fix for C++20 mode, but it has an active maintainer unlike Rational. The GitHub issue for it was closed (I've reopened it) because it was assumed to be a defect in the standard and one that vendors would fix. We did have some discussion on the C++ standard committee reflector about this, however - whatever the future change to the standard is - GCC and Clang with -std=c++20 that implement these rules have already been released and users are using it, so we should fix this in Boost 1.75. Glen

2 1

Re: [boost] [release] 1.75.0 post-beta merges
by Glen Fernandes 16 Nov '20

16 Nov '20

Robert Ramey wrote: > request permission to sync changes in develop into master for > two libraries: serialization and safe_numerics. They've been ready for > some time, I just forgot to do it in time. Go ahead. Glen

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[release] Boost 1.74.0 beta 1 released
by Marshall Clow 14 Nov '20

14 Nov '20

Boost release 1.75.0 beta 1 is now available at: <https://dl.bintray.com/boostorg/beta/1.75.0.beta1/source/> The SHA256 checksums are as follows: 3f01d3e5dc822e151892040d4667e364ea808d208d2e49cc7a1802bd4da3d4cc boost_1_75_0_b1.7z 9b75a80f845d4ae312e3c9151ffdfe3fed450973095e0a15c68d0be394f2f2df boost_1_75_0_b1.tar.bz2 123519d4b056fbbd69e452db880abe2c7e55f21779d44a4d6b6c714d5c13c3ee boost_1_75_0_b1.tar.gz b73e01d22d5b3d2ff82f14a371e3974fab30448bf6ff5ac8b9c829539a19c2d7 boost_1_75_0_b1.zip For details of what's in the release, see <https://www.boost.org/users/history/version_1_75_0.html>. Please download the beta, give it a try, and report any problems you encounter. Thanks, -- The Boost Release Team

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Boost.Exception regression in 1.75.0 beta 1
by Niall Douglas 14 Nov '20

14 Nov '20

If you diagnose the test failures (which are present across all compilers) in https://www.boost.org/development/tests/develop/developer/outcome.html which report failures of the form: ``` unknown location(0): fatal error: in "works_outcome": Throw location unknown (consider using BOOST_THROW_EXCEPTION) Dynamic exception type: struct boost::wrapexcept<class boost::exception_ptr> libs\outcome\test\tests\core-outcome.cpp(173): last checkpoint *** 1 failure is detected in the test module "Outcome" ``` The cause is test code such as: ``` boost::system::error_code ec(5, boost::system::system_category()); auto e = boost::copy_exception(boost::system::system_error(ec)); // NOLINT outcome<int> m(e); BOOST_CHECK_THROW(m.value(), boost::system::system_error); ``` Outcome calls boost::rethrow_exception() to rethrow the exception_ptr. boost::rethrow_exception() is not rethrowing the boost::system::system_error held within the boost::exception_ptr. It is throwing instead boost::wrapexcept<class boost::exception_ptr>. This causes BOOST_CHECK_THROW() to not correctly trap the type of exception thrown, and thus the test fails. boost::wrapexcept<E> inherits from E. It seems to me therefore that catching a const E& ought to catch throws of boost::wrapexcept<E>, and therefore this code is correct. I double checked this at https://wandbox.org/permlink/n9Wjb5cPpfHEFalp, and indeed it works as expected. However, obviously enough this is failing, and it was not failing in Boost 1.74, so this is a regression. I am stumped as to the exact cause. This affects all platforms, POSIX, Windows, clang, GCC and MSVC. Niall

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permission to merge fix
by Oliver Kowalke 08 Nov '20

08 Nov '20

Do I get permission to merge a fix related to boostorg/fiber#264 <https://github.com/boostorg/fiber/issues/264> into master? Oliver

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[release] Boost 1.75.0 Beta 1 Release Candidate 1
by Marshall Clow 07 Nov '20

07 Nov '20

The first release candidates for the 1.75.0 beta release are now available at: <https://dl.bintray.com/boostorg/release/1.75.0.beta1/source/> The SHA256 checksums are as follows: c271f488c7c8de7c147bf8675d578fb2f06c6c171d9547c5a40cddccb9f2a6c4 boost_1_75_0_b1_rc1.7z 0db0944e9d2250907e011900eea304ca055d1c418d38b3fbb1eee692a6b851a6 boost_1_75_0_b1_rc1.tar.bz2 624bd6b03d86bf1387b4e8927dab16b4198f255f15dd71d6a8c1c5ec270584b3 boost_1_75_0_b1_rc1.tar.gz 07ddca7c39ea9152bad73bee4f10f2c9c8e3a2d7e153aa945a343f83eca5db59 boost_1_75_0_b1_rc1.zip As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. -- The Release managers

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[1.75 release] Merging 'develop' to 'master' for Embarcadero fix
by Edward Diener 06 Nov '20

06 Nov '20

A number of libraries have my PR to enable Embarcadero C++ clang-based compilers for Boost in their 'develop' branch but the branch has not been merged to 'master' for the 1.75 release. In the large majority of cases my PR for Embarcadero is the only difference between 'develop' and 'master'. These libraries are: assign circular_buffer container_hash date_time foreach graph iostreams numeric_conversion optional pool ptr_container random static_assert thread typeof units unordered If any of the maintainers of these libraries could see fit to get my PR in 'master' from 'develop' for the 1.75 release, it would be appreciated. I can assert that the PR causes no problems in the 'develop' regression tests for the aforementioned libraries. I have also opened up an issue for each of the aforementioned libraries in their Github page regarding my request.

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[release] Master branch now closed for 1.75.0 beta release
by Marshall Clow 06 Nov '20

06 Nov '20

Please do not make any commits to the master branch.

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