October 2017 - Boost - lists.preview.boost.org

Release Note responsibilites for maintainers
by James E. King, III 24 Oct '17

24 Oct '17

The upcoming release of 1.66.0 will be my first release in a maintainer role. How are the release notes generated and what are maintainer's responsibilities during each phase of the release cycle? Thanks, Jim

2 1

RFC.. Steering Committee Bylaws Proposal
by Rene Rivera 24 Oct '17

24 Oct '17

It has become clear to me, and some others, that the recent decisions of the Steering Committee have exposed various problems with how the Steering Committee operates. At CppCon I met with some of the Steering Committee and expressed the concerns with them. I also explained, from my experience in other organizations, how such issues are managed. The result of that is that I will be proposing the Steering Committee adopt operating Bylaws. But before formally presenting them to the Steering Committee I'd like get feedback on them <http://bit.ly/2hI22DN>[1]. The Bylaws hopefully address some key issues that I feel are at the core of the current problems: * Decisions can be made without input from interested parties. * Opaque selection of members. * No recourse by library authors to correct problems. This follows the original goals of the formation of the formation of Steering Committee of being transparent and responsive < http://bit.ly/2yoL5Ij>[2]. [1] <https://github.com/grafikrobot/other/blob/master/ bsc-bylaws-proposal/Boost%20Steering%20Committee%20Bylaws.md> [2] <https://github.com/grafikrobot/other/blob/master/ bsc-bylaws-proposal/2011-05-20%20Boost%20governance%20annotated.pdf> -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net

13 35

boost timer, warnings, backlog
by James E. King, III 24 Oct '17

24 Oct '17

I'm seeing a warning for use of "long long" in a lot of builds, originating in Boost.Timer. I like warning-free builds, so this is something I would like to see resolved. There's an issue in Boost Trac for it: https://svn.boost.org/trac10/ticket/12996 There's a pull request open since April for it (and 3 more going back a couple years): https://github.com/boostorg/timer/pull/4 Is this module still actively maintained? Thanks, Jim

5 6

[Outcome] WG21 papers of interest to Boost and Outcome
by Niall Douglas 24 Oct '17

24 Oct '17

This October's mailing has lots and lots of WG21 papers related to Outcome which were strongly influenced by the peer review here in May. Boost members who contributed to the Outcome v1 review in May should please take a bow and accept thanks for spurring so much discussion and debate regarding these potential future C++ features. Thank you. 1. http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0323r3.pdf Utility class to represent expected object 2. http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0650r1.pdf C++ Monadic interface 3. http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0762r0.pdf Concerns about expected<T, E> from the Boost.Outcome peer review 4. http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0779r0.pdf Proposing operator try() (with added native C++ macro functions!) 5. http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0786r0.pdf SuccessOrFailure, ValuedOrError and ValuedOrNone types 6. http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/p0824r0.pdf Summary of SG14 discussion on <system_error>: towards exception-less error handling Niall -- ned Productions Limited Consulting http://www.nedproductions.biz/ http://ie.linkedin.com/in/nialldouglas/

1 0

[timer][msvc] Universal-Windows advice needed
by Beman Dawes 23 Oct '17

23 Oct '17

Pull request https://github.com/boostorg/timer/pull/3 is a fix for Universal-Windows: "universal-windows: GetProcessTimes is not supported". Does anyone have a clue whether the P/R is correct and the best solution? Is the stated problem a temporary one that Microsoft will likely fix, and will it likely be a permanent limitation? Thanks, --Beman

1 0

[system] Header-only Boost.System by default ?
by Damien Buhl 23 Oct '17

23 Oct '17

Dear Boost, Is there any reason why Boost system couldn't be set to be header only by default ? Defining both macros allows it : - BOOST_SYSTEM_NO_DEPRECATED - BOOST_ERROR_CODE_HEADER_ONLY This ease, speeds up and reduces binary size greatly, that it's sad that non-aware Boost User needs to link to some dll/so/dylib of Boost.System per default. It has been in many releases of Boost, wouldn't it be good to set it to be the default for a next release ? Cheers, -- Damien Buhl Software Developer +33 6 77 43 10 05

10 25

[BoostBook] how to automatically test code examples?
by Hans Dembinski 19 Oct '17

19 Oct '17

Hi everyone, I am using BoostBook to prepare the documentation for the proposed histogram library https://github.com/HDembinski/histogram I have written a good deal of the documentation already, and it compiles fine with bjam (thanks to Klemens who showed me how). It says in the BoostBook documentation http://www.boost.org/doc/libs/1_65_1/doc/html/boostbook.html "The BoostBook format allows testcases to be generated by weaving together program fragments from example programs in the documentation. This capability is integrated with testsuite generation so that example programs are normal tests in BoostBook." That's awesome, I would love to use this feature, but the documentation is not explaining how to actually do that. I found the element "testsuite" which probably does what I want. I went on to scan the Boost repository for this BoostBook element, but couldn't find an example to copy from. Could someone help me out? How do I modify my BoostBook and Jam files to generate tests out of the code examples in the documentation? Best regards, Hans

6 14

[msvc] #warning preprocessor directive
by Beman Dawes 17 Oct '17

17 Oct '17

I find it very irritating that VC++ does not support #warning, and have opened a feature request: https://visualstudio.uservoice.com/forums/121579-visual-studio?query=Add%20… The last time #warning was suggested it was rejected because not enough people voted for it. So please consider upvoting it on the above link. The lack of #warning affects Boost libraries in that developers avoid otherwise useful warnings because of the hassle for using an extension not supported by VC++. --Beman

6 20

Merged #149, "Encode architecture and address model in versioned layout names"
by Peter Dimov 17 Oct '17

17 Oct '17

I've just merged https://github.com/boostorg/boost/pull/149, "Encode architecture and address model in versioned layout names", into the develop branch. Let's see how this goes. Welcome to 2005. :-)

6 10

How to build boost on windows with Clang/LLVM
by degski 17 Oct '17

17 Oct '17

With the latest snapshot builds of clang, thin LTO is supported on Windows. This thin LTO gives very interesting (speed) results. I would therefore like to start to build boost with clang and no longer with msvc. I have msvc 15.4 installed (the latest incarnation). I made a project-config.jam: =============start=============== import option ; using clang : 6.0 : clang++.exe : <cxxflags>-fmacro-backtrace-limit=0 <cxxflags>-Wno-invalid-token-paste <compileflags>-fmsc-version=1911 <linkflags>-fuse-ld=lld <linkflags>-flto=thin ; option.set keep-going : false ; ==============end=============== I call: bjam -a -d+2 cxxflags="-O0" "-sZLIB_SOURCE=%HOME%\zlib-1.2.8" "-sBZIP2_SOURCE=%HOME%\bzip2-1.0.6" variant=debug instruction-set=haswell threading=multi link=static runtime-link=static --prefix=%PREFIX% --build-dir=c:\boost-build address-model=64 architecture=x86 toolset=msvc --without-python --without-mpi --disable-filesystem2 install This does not work. What is the proper way to compile boost on windows using clang++.exe or clang-cl.exe for use with VS2017. degski -- "*Ihre sogenannte Religion wirkt bloß wie ein Opiat reizend, betäubend, Schmerzen aus Schwäche stillend.*" - Novalis 1798

3 7

Looking for a task to contribute to boost
by vivek pandya 17 Oct '17

17 Oct '17

Hello Boost Developers, I am Vivek. I contribute small patches to LLVM project. I wanted to work for boost open source project to enhance my C++ knowledge. Could someone suggest some project to me? I will be able to complete task suitable for Google Summer of Code with help and guidance form community. Please also suggest required assignments as I am not a frequent user of Boost libraries. Thanks, Vivek

3 2

Recommend dropping test coverage on msvc-7.1 and msvc-8.0
by James E. King, III 16 Oct '17

16 Oct '17

MSVC 7.1 and MSVC 8.0 are currently listed as "tested" in the Boost 1.65.1 release notes however there are a lot of projects that do not seem to support them well, if at all: http://www.boost.org/development/tests/master/developer/issues.html <http://www.boost.org/development/tests/develop/developer/issues.html> It looks like a large number of libraries will no longer build properly against them based on this report. I'm not sure what the procedure is to come to an agreement to drop a compiler in a release, but it looks like we should consider dropping msvc-7.1 and msvc-8.0. These are very old compilers for Windows development. Dropping them would also allow folks to more easily focus on failures in this report to make sure a release is as clean as possible and simplify the test matrix a little bit. Appveyor only supports back to Visual Studio 2010 at this point, so our ability to get pre-commit checks on compilers before msvc-10.0 is solely based on maintainer effort. I suspect this effort is no longer justified based on the age of the compilers. Thanks - Jim

13 31

Bjam broken on windows with VS2017?
by degski 16 Oct '17

16 Oct '17

My lappie has vs2017 installed, latest (15.4) version, from some days ago. I did the following: 1. Put a clean copy of the boost 1.65.1 source in c: root. 2. issue 'bootstrap.bat' in c:\boost_1_65_1\ (ordinary prompt, no vs thingy). This creates a project-config.jam msvc file. 3. Copied (overwrote project-config.jam) the below contents as project-config.jam to c:\boost_1_65_1\ =======start======= import option ; using clang : 6.0 : "C:\\Program Files\\LLVM\\bin\\clang++.exe" : <compileflags>-fmsc-version=1911 <compileflags>-DBOOST_USE_WINAPI_VERSION=0x1000 <compileflags>-DBOOST_USE_WINDOWS_H=1 <compileflags>-D_WIN32_WINNT=0x1000 <compileflags>-DNOMINMAX <ranlib>"C:\\Program Files\\LLVM\\bin\\llvm-ranlib.exe" <archiver>"C:\\Program Files\\LLVM\\bin\\llvm-ar.exe" <linkflags>-fuse-ld=lld <linkflags>-flto=thin ; option.set keep-going : false ; =======end======== 4. issue 'bjam -d0 --clean' The script of that, and the result is below: Microsoft Windows [Version 10.0.15063] (c) 2017 Microsoft Corporation. All rights reserved. C:\Users\User>cd \ C:\>cd boost_1_65_1 C:\boost_1_65_1>bootstrap.bat Building Boost.Build engine Bootstrapping is done. To build, run: .\b2 To adjust configuration, edit 'project-config.jam'. Further information: - Command line help: .\b2 --help - Getting started guide: http://boost.org/more/getting_started/windows.html - Boost.Build documentation: http://www.boost.org/build/doc/html/index.html C:\boost_1_65_1>bjam -d0 --clean 'C:/Program' is not recognized as an internal or external command, operable program or batch file. etc.. etc... the rest is history? Any ideas? degski

2 3

'Fibre safe optimisations' with gcc/clang (non Windows target) and Boost.Context
by james 15 Oct '17

15 Oct '17

I was considering whether I could/should build an actor system on Rust rather than C++, since it would be an interesting exercise for me. And then I found this article: https://www.reddit.com/r/rust/comments/56wgzq/status_of_coroutines/ In particular: > we noticed that the Rust stdlib is actually using TLS (!) to implement exceptions It seems to me that in practice other compilers might use some sort of thread-local hook for exceptions, whether it is TLS or something lower-level that supports TLS. And that the issue is whether the compiler will assume that the address of the TLS (or thread information block etc) is volatile, or can be cached in a stack frame or register across calls. It seems to me that any such caching of an address might cause difficulty, not just in Rust but also other languages. Microsoft's compiler explicitly has a switch for 'fibre safe optimisations' that disables such caching. The worry I have is code like this: void foo() { try { A() } catch (...) {} B(); // Can switch the context to another underlying OS thread try { C() } catch (...) {} } I am concerned that information about exception handling that was acquired for the first try block, might be retained in the frame and reused in the second try block. and the information might be captured in the frame and/or registers that get saved in the context, but in an arbitrary way. I suspect that access to explicit ABI TLS or C++ thread local is also impacted, although it might be easier to avoid. I guess its not a complete show-stopper if we ensure that fibres never migrate between OS threads, but that is somewhat inconvenient. So - is this actually a Rustc specific issue?

1 0

printf official specs or docs, ISO C99, and C++
by James E. King, III 14 Oct '17

14 Oct '17

I found https://svn.boost.org/trac10/ticket/10541 today and my guess is Boost.Format hasn't been updated to support the ISO C99 extensions, or the Microsoft type formats. Before any work is done on this, I'm looking for any official C++ documentation related to printf support requirements. For example the compatibility section in http://www.cplusplus.com/reference/cstdio/printf/ indicates certain language levels have requirements. Thanks, Jim

3 3

[build] Building library with vc++ 64-bit does not find vcvarsall.bat
by Edward Diener 13 Oct '17

13 Oct '17

If I build any library with any version vc++ 64-bit compiler, by using address-model=64, the vcvarsall.bat is looked for at, for example with msvc-14.0, C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/bin/vcvarsall.bat and is not found. Naturally this leads to basic compilation failures. The path for vcvarsall.bat for msvc-14.0 is C:/Program Files (x86)/Microsoft Visual Studio 14.0/VC/vcvarsall.bat instead. All versions of vc++ follow this path structure for vcvarsall.bat Building with any version of vc++ 32-bit, by not specifying the address-model, works correctly.

3 4

1.65.1 as modular packages on Conan.io
by Rene Rivera 13 Oct '17

13 Oct '17

Following on with the announcement before CppCon of the 1.64.0 modular packages here we are with more. I'm pleased to announce that the 1.65.1 Boost C++ Libraries are now available individually using the Conan package manager. There's even some improvements for the 1.64.0 package also :-) Find out more from the Bincrafters post here <http://bit.ly/2g6VEpp>[1]. For help using the packages you can bug the Bincrafters team in the #Conan CppLan Slack channel <http://bit.ly/2ykeqC0>[2]. Conan is a C/C++ (and more) package manager that supports an open ended set of build system and tool integrations including: VisualStudio, Xcode, CLion, Ninja, QMake, Premake, and yes even CMake <http://bit.ly/2xzhpbg>[3]. [1] <https://bincrafters.github.io/2017/10/13/Conan-Packages-Boost-1-65-1/> [2] <https://cpplang.now.sh/> [3] <http://docs.conan.io/en/latest/integrations.html> -- -- Rene Rivera -- Grafik - Don't Assume Anything -- Robot Dreams - http://robot-dreams.net

1 0

Maintainers: Adding Coverity Scan to your library
by James E. King, III 12 Oct '17

12 Oct '17

I have completed the work necessary to add Coverity Scan to Boost.Uuid and wanted to share the steps involved. This work can be carried into other libraries fairly easily. 1. Go to Coverity Scan: https://scan.coverity.com/ 2. Sign up/in with your Github account. 3. Create a project for your boostorg/library. It will take about 24 hours for them to activate your account so that you can use the results browser. To run a coverity scan manually: 1. Check out your project master (or whatever branch you want to scan). 2. cd into BOOST_ROOT (where "libs/" is located) 3. Run the libs/uuid/covscan.sh script with the following environment variables set: A. COVERITY_SCAN_TOKEN: the project token in coverity scan B. COVERITY_SCAN_NOTIFICATION_EMAIL: your email C. SELF: your library name, for example SELF=uuid for Boost.Uuid 4. You will need to clean up some cruft it leaves behind as the script is designed for Travis CI - just a couple directories starting with "cov" and a tar.xz file. To integrate coverity scans for every pull request or push into master with Travis CI: 1. Make sure you have Travis CI set up properly to build your project. 2. Copy the Coverity Scan stanza from libs/uuid/.travis.yml into your .travis.yml file. Note that the Boost.Uuid travis configuration now uses jobs instead of matrix, as jobs allow for conditions. I would encourage you to convert your .travis.yml to use jobs as well. 3. The next pull request into master, or the next push into master, will trigger a build, and any build for master will run covscan.sh and upload the data. You can add component regular expressions to ignore/omit other boost library errors if you wish. Here are the results for Boost.Uuid. I have not excluded other components yet: https://scan.coverity.com/projects/boostorg-uuid Initially I saw a flurry of "unhandled exception" items which I dismissed as intentional (i.e. I want the test to segfault if an unexpected exception is thrown so that I can debug it), and that will likely be a common practice for test files, but should not be for implementations. I also caution folks against marking something as a false positive. Approach it with the mindset of, "it must be a fault of the library" before jumping to, "it must be a fault in Coverity" and really convince yourself it is not a code issue. Even if you do not have travis integration in your library, running a manual scan will help you improve the quality of your library, so I recommend everyone at least do that much. - Jim

5 5

Asciidoc, an alternative for documentation
by Peter Dimov 12 Oct '17

12 Oct '17

I've been experimenting with Asciidoc-based documentation, using Boost.Assert as my guinea pig. The good thing about Asciidoc is that Github shows a preview and you can edit it directly on github.com. This is how the source looks there: https://github.com/boostorg/assert/blob/feature/asciidoc/doc/index.adoc https://github.com/boostorg/assert/blob/feature/asciidoc/doc/assert.adoc https://github.com/boostorg/assert/blob/feature/asciidoc/doc/current_functi… This is how the generated HTML documentation looks, using the default stylesheet, without any customizations on my part: https://rawgit.com/boostorg/assert/feature/asciidoc/doc/html/assert.html And this is how the generated PDF looks: http://pdimov.com/tmp/assert.pdf The tool that produces these is Asciidoctor, http://asciidoctor.org/ .

13 34

Boost.Format Library Maintenance
by James E. King, III 12 Oct '17

12 Oct '17

Currently the Boost.Format library is being maintained by the CMT. I would like to petition for that responsibility and lighten their case load further. I recently assumed maintenance for Boost.Uuid, and I have added Universal Windows Platform support to Boost.WinAPI and Boost.Predef so that folks will have an easier time making Windows Store compatible apps. I have also been working on a change that will add UWP support to Boost.Random and turn it into a header-only library, and expect to submit that in the next few days. I would like to shore up the CI environment for Boost.Format and groom the backlog in trac and on github, and get all the open issues resolved. Thanks for your consideration, Jim King

3 3

[Build] How to build libboost_lzma?
by degski 12 Oct '17

12 Oct '17

Up till now I have built libboost_zlib and libboost_bzip2 by setting ZLIB_SOURCE and BZIP2_SOURCE variables to their respective source directories on the bjam command-line and the libraries get built without fail. I gather (from the bjam output) their is now support for lzma, which I would like to use. I've tried a similar (did not find a doc) approach with LZMA by feeding "-sLZMA_SOURCE=c:\xz-5.2.3" (from https://tukaani.org/xz/xz-5.2.3.tar.gz) to bjam. This does not work. How do I make bjam build libboost_lzma? Thanks in advance. degski -- "*Ihre sogenannte Religion wirkt bloß wie ein Opiat reizend, betäubend, Schmerzen aus Schwäche stillend.*" - Novalis 1798

1 1

Boost Serialization: Serializing large objects
by Adlai Shawareb 12 Oct '17

12 Oct '17

We are trying to text serialize a 700 MB object. We are getting an archive_exception: input stream error. This is on a 32-bit QNX system. * Is there a limit to the size of the object that can be serialized? * Is there anything we can do to fix or work around this? Here is the code we are using: std::stringstream ss_; boost::archive::text_oarchive oa(ss_, boost::archive::no_header); oa << &object; Adlai

4 11

interest in a stateful pointer library?
by Hans Dembinski 11 Oct '17

11 Oct '17

Hi everyone, I wrote a variant of std::unique_ptr, called tagged_ptr, which allows safe read/write access to a customisable number of bits in the pointer variable. You can find the library on github: https://github.com/HDembinski/stateful_pointer You can use those bits to store extra state in the pointer variable at no extra space cost. I did some benchmarks to show that the computational overhead required for the bit manipulation is also negligible. One needs little imagination to find good use for those bits. As a proof of principle, I wrote an STL compatible string class which has the size of const char*, but can store up to 7 ASCII characters (on a 64 bit system) without allocating any memory on the heap (aka small string optimisation). The string class is also included in the library. To make this work, I use one of the bits in the pointer variable to recognise whether the variable should be interpreted as a pointer or as a char array. The Stateful Pointer library is C++11, header-only, and AFAIK platform-independent (in theory, this has not been tested so far). To create pointers which allow one to use a certain number of bits for other purposes, I rely on Boost.Align to allocate aligned memory. How does it work? Aligned memory, as the name implies, does not point to any address in memory, only certain addresses are allowed. For example, a two-byte aligned memory block can only have an even address. Therefore the lowest bit in the address is always zero. Since the bit is guaranteed to be zero, we can use it to store something else and mask it to zero whenever we need to dereference the pointer. I think this is a generally useful class to have in Boost, so is there some interest in polishing it up in a review process? Best regards, Hans

7 18

Master Regression Tests Failing
by Tom Kent 11 Oct '17

11 Oct '17

It appears that we haven't had any successful runs of the regression tests on master since last Friday afternoon. Looking at some logs, I'm seeing output like below. Any ideas? Tom notice: [lzma] Condition /var/boost/run/boost_bb/src/build/feature.jam:140: in feature.feature from module feature error: feature already defined: error: in feature declaration: error: feature "threadapi" : "pthread" "win32" : "propagated" /var/boost/run/boost_root/libs/thread/build/Jamfile.v2:151: in modules.load from module Jamfile</var/boost/run/boost_roo t/libs/thread/build> /var/boost/run/boost_bb/src/build/project.jam:325: in load-jamfile from module project /var/boost/run/boost_bb/src/build/project.jam:64: in load from module project /var/boost/run/boost_bb/src/build/project.jam:89: in load-used-projects from module project /var/boost/run/boost_bb/src/build/project.jam:75: in load from module project /var/boost/run/boost_bb/src/build/project.jam:89: in load-used-projects from module project /var/boost/run/boost_bb/src/build/project.jam:75: in load from module project /var/boost/run/boost_bb/src/build/project.jam:113: in load-parent from module project /var/boost/run/boost_bb/src/build/project.jam:464: in initialize from module project /var/boost/run/boost_bb/src/build/project.jam:306: in load-jamfile from module project /var/boost/run/boost_bb/src/build/project.jam:64: in load from module project /var/boost/run/boost_bb/src/build/project.jam:145: in project.find from module project /var/boost/run/boost_bb/src/build-system.jam:535: in load from module build-system /var/boost/run/boost_bb/src/kernel/modules.jam:295: in import from module modules /var/boost/run/boost_bb/src/kernel/bootstrap.jam:139: in boost-build from module /var/boost/run/boost_regression/boost-build.jam:57: in module scope from module # Searching for "process_jam_log" in "/var/boost/run/boost_regression/stage/bin"... Traceback (most recent call last): File "run.py", line 71, in <module> runner(root) File "/var/boost/run/boost_regression_src/regression.py", line 287, in __init__ self.main() File "/var/boost/run/boost_regression_src/regression.py", line 624, in main getattr(self,action_m)() File "/var/boost/run/boost_regression_src/regression.py", line 581, in command_regression self.command_setup() File "/var/boost/run/boost_regression_src/regression.py", line 352, in command_setup self.build_if_needed(self.process_jam_log,self.pjl_toolset) File "/var/boost/run/boost_regression_src/regression.py", line 715, in build_if_needed tool[ 'build_path' ] = self.tool_path( tool ) File "/var/boost/run/boost_regression_src/regression.py", line 740, in tool_path , '\n'.join( [ name_or_spec[ 'path' ], build_dir ] ) Exception: Cannot find "process_jam_log" in any of the following locations: /var/boost/run/boost_regression/stage/bin/process_jam_log /var/boost/run/boost_regression/stage/bin

9 19

[ANN] Boost.UI - a new C++ GUI library
by Kolya Kosenko 10 Oct '17

10 Oct '17

Hello, Here is my C++ GUI library based on Boost, it - is cross-platform - uses native system-provided widgets - has STL-like and Boost-like API - compatible with other Boost libraries - supports modern C++11/14/17 features Currently supported modules: - Graphics - Widgets * Command widgets * Data input-output widgets + Date and time pickers + Strings container widgets + Text widgets * Informational widgets + Logging * Containers + Alerts + Notifications + Prompts - Layouts - Events - Audio - Coordinates - Localization - Thread support - Helpers Documentation (and "Hello, World!" application source code): https://kosenko.github.io/boost.ui/ Source code: https://github.com/kosenko/ui Beman's challenge: https://github.com/kosenko/ui/blob/master/example/cpp11/beman.cpp Re-implemented GUI examples from Bjarne Stroustrup's book: https://github.com/kosenko/ui/blob/master/example/cpp11/stroustrup.cpp Other examples: https://github.com/kosenko/ui/tree/master/example What do you think? Regards, Kolya Kosenko.

11 21