April 2021 - Boost - lists.preview.boost.org

CMake Announcement from Boost Steering Committee
by Jon Kalb 13 Aug '24

13 Aug '24

The libraries produced by the Boost community have had a greater impact on the way that the C++ community writes code than any other library implementation. The focus of the Boost community will always be on the libraries, but it is undeniable that we are dependent on and often limited by the infrastructure of our trade. Years ago, the move to Git was contentious; yet, it was required to improve development. In a similar vein our build system has become an impediment for many developers and users, existing and prospective. Therefore, we, the Steering Committee, announce to the Boost community our desire and intent to move Boost’s build system to CMake for users and developers alike. We are soliciting comments and proposals from the community to guide the process and the goals. Our desire is that the community can come to consensus by the end of the calendar year with a vision of supporting users and developers. We understand that the actual process of achieving the end goal will be long, time consuming, and not without its share of conflict. We also recognize that the Boost community is comprised of bright and passionate individuals that are eager to get involved and help get work done. The members of the Steering Committee have been encouraged by the discussions and activity surrounding CMake on the mailing lists over the years and know that many people have voiced visions. We hope that each of you rejoins the discussion to support this initiative and contributes to the common goal of improving Boost’s integration into the broader C++ ecosystem. For the Boost Steering Committee, Jon Kalb, Chair jonkalb(a)boost.org

49 199

Boost.Text is looking for a (mini-)review manager
by Zach Laine 07 Dec '22

07 Dec '22

I've made all the recommended changes to Boost.Text that came up in the review. Glen, the previous review manager, recommended a mini review of Boost.Text once I'd made those changes. If you'd like to manage the mini-review, please let me know. For everyone, including potential reviewers and review managers, here are the major changes: * All the specific review feedback issues have been addressed. * The string layer is now gone. * The text layer got a major re-work. It is now a set of template-based adaptors (basic_text<>, vs. a text typedef. etc.), which lets everyone get what they want. You can change the underlying storage type (including whatever allocator you prefer), select UTF-8 or UTF-16, and change the normalization form. Glen recommended I drop this layer, but the library is way less useful without this stuff, and these changes address all the concerns raised about the text layer in the review. The updated docs can be found here: https://tzlaine.github.io/text/doc/html/index.html Oh yeah, and I added concept constraints to the whole library when you build in C++20 mode. Zach

17 46

[review][JSON] Review of JSON starts today: Sept 14 - Sept 23
by Pranam Lashkari 09 Aug '22

09 Aug '22

Boost formal review of Vinnie Falco and Krystian Stasiowski's library JSON starts today and will run for 10 days ending on 23 Sept 2020. Both of these authors have already developed a couple of libraries which are accepted in Boost(boost beast and Static String) This library focuses on a common and popular use-case for JSON. It provides a container to hold parsed and serialised JSON types. It provides more flexibility and better benchmark performance than its competitors. JSON highlights the following features in the documentation: - Fast compilation - Require only C++11 - Fast streaming parser and serializer - Easy and safe API with allocator support - Constant-time key lookup for objects - Options to allow non-standard JSON - Compile without Boost, define BOOST_JSON_STANDALONE - Optional header-only, without linking to a library (a point I would like to add in highlight: it has cool Jason logo 😝) To quickly understand and get the flavour of the library take a look at "Quick Look" <http://master.json.cpp.al/json/usage/quick_look.html> You can find the source code to be reviewed here: <https://github.com/CPPAlliance/json/tree/master> You can find the latest documentation here: <http://master.json.cpp.al/> Benchmarks are also given in the document which can be found here: <http://master.json.cpp.al/json/benchmarks.html> Some people have also given the early reviews, the thread can be found here: <https://lists.boost.org/Archives/boost/2020/09/249745.php> Please provide in your review information you think is valuable to understand your choice to ACCEPT or REJECT including JSON 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 here: <http://www.boost.org/community/reviews.html> Thank you for your effort in the Boost community. -- Thank you, Pranam Lashkari, https://lpranam.github.io/

21 73

[container] Contributing 'stationary_vector' to Boost
by Mehrdad Niknami 13 Jun '22

13 Jun '22

Hi all, Happy new year! New mailing list member here. I've developed an STL-style stationary_vector class that retains elements in-place when growing. Very briefly, it is effectively a piecewise-contiguous vector, with the following advantages over vector: - Appending has O(1) overhead in the *worst* case (e.g., push_back() does not move elements) - Insertion and random-access can be done in parallel, as prior iterators & references remain valid This has a variety of benefits, including better UX (no "hiccups" due to reallocations), and the ability to simplify parallel processing of streaming data. It occurred to me the larger C++ community might find this useful. I was wondering if there would be interest in incorporating it into Boost.Container, and if so, what steps I could take to make that happen? I'm of course happy to discuss the design etc. with anyone who might be interested. Summary: https://github.com/mehrdadn/libvital/blob/master/doc/vital/container/statio… Implementation: https://github.com/mehrdadn/libvital/blob/master/include/vital/container/st… Thank you, Mehrdad

7 19

Adding my sorting algorithm, ska_sort, to boost, attempt 2
by Malte Skarupke 24 Nov '21

24 Nov '21

Hi everyone, I started a discussion about this in October, but at the time the maintainer of the sort library was busy, then I was busy, so now it's January... I wrote a generalized version of radix sort a couple years ago and gave a talk about it here: https://www.youtube.com/watch?v=zqs87a_7zxw I would like to get a new version of that sorting algorithm into boost. It's faster than what I showed several years ago. It's also even more general and has a new interface that should be easier to extend. I uploaded the code here: https://github.com/skarupke/sort/tree/master The documentation is also already updated with new benchmark results. Let me know what's required to get this into boost. Would you like this in the form of a pull request? One of the big things that probably needs review is the interface, since radix sorting works differently than comparison based sorting. For most normal uses you just need to provide a sort key, but more complicated cases can get more complicated. I tried very hard to make everything easy, but I'd also be curious if others can come up with better ways of doing the interface. Thanks, Malte -- Malte Skarupke malteskarupke(a)fastmail.fm

8 10

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

5 6

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

6 25

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

2 2

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

2 2

[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.

1 0

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

3 2

[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

1 0

[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

1 0

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

1 0

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

1 0

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

1 0

[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

1 0

[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

3 3

[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…

3 2

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.

2 2

[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

1 0

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

1 0

[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>

2 5

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

5 9

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.

1 0

[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.

2 1

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

1 0

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

2 1

[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.

2 1

[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

4 4

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

5 5

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…

1 0

[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

1 0

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 :)

2 1

[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

17 34

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

6 29

[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_…

2 1

[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)

2 2

[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.

1 0

[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.

12 34

[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!

2 4

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

2 2

[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;

3 9

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

4 7