October 2010 - Boost - lists.boost.org

[Review] Final Few Days for Formal Review of Proposed Boost.Ratio Library
by Anthony Williams 10 Oct '10

10 Oct '10

Hi everyone, If you have already posted a review, then thank you. For the rest of you: the review of Vicente Botet' Ratio library runs until October 11th, 2010 (this coming Monday), so please submit your reviews. What is it? ======== Portable implementation of the C++0x Standard Library's compile-time rational arithmetic working on C++03 and C++0x compilers. See the current C++0x working draft at http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2010/n3126.pdf Boost.Ratio provides: * A class template, ratio, for specifying compile time rational constants such as 1/3 of a nanosecond or the number of inches per meter. ratio represents a compile time ratio of compile time constants with support for compile time arithmetic with overflow and division by zero protection * It provides a textual representation of boost::ratio<N, D> in the form of a std::basic_string. Other types such as boost::duration can use these strings to aid in their I/O. This library is header-only and is designed to be generic and useful in a lot of areas of math and numerics C++ programming, in particular it is absolutely needed for the proposed Boost.Chrono and Boost.Stopwatches libraries which are currently in the review queue. Getting the library ============= The latest version of this library may be downloaded from vault: http://www.boostpro.com/vault/index.php?action=downloadfile&filename=ratio.… SVN: http://svn.boost.org/svn/boost/sandbox/chrono (directories boost/ratio and libs/ratio) and the docs may be viewed here html: http://svn.boost.org/svn/boost/sandbox/chrono/libs/ratio/doc/html/index.html pdf: http://svn.boost.org/svn/boost/sandbox/chrono/libs/ratio/doc/ratio.pdf You can get all these information also (which should avoid some long links) from http://svn.boost.org/trac/boost/wiki/LibrariesUnderConstruction#Boost.Ratio It is worth noting that the tests included in the zip file are relatively sparse. Vicente has an extensive suite of tests licensed under the LLVM license. He has posted a message on the Boost Developers mailing list regarding the license requirements for tests (See http://thread.gmane.org/gmane.comp.lib.boost.devel/208978) and is awaiting the outcome of that discussion before making the tests available. Writing a review ================ If you feel this is an interesting library, then please submit your review to the developer list (preferably), or to the review manager. Here are some questions you might want to answer in your review: - 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 what compiler? 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? And finally, every review should answer this question: - Do you think the library should be accepted as a Boost library? Be sure to say this explicitly so that your other comments don't obscure your overall opinion. Anthony Review Manager for the proposed Boost.Ratio library -- Author of C++ Concurrency in Action http://www.stdthread.co.uk/book/ just::thread C++0x thread library http://www.stdthread.co.uk Just Software Solutions Ltd http://www.justsoftwaresolutions.co.uk 15 Carrallack Mews, St Just, Cornwall, TR19 7UL, UK. Company No. 5478976

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Variadic Data Library in sandbox
by Edward Diener 10 Oct '10

10 Oct '10

I have put in the sandbox the Variadic Macro Data library, or VMD. This library supplies variadic macro functionality and integrates variadic macros with the Boost PP library without changing the latter in any way. The library in the sandbox is in the variadic_macro_data folder. The library is a header-only library of macros. There is documentation and tests and the appropriate jamfiles for both. To build the documentation you need doxygen but I have also provided documentation in an html subfolder. The main use of the library is to be able to pass variadic data to macros, and in particular to extract variadic data elements or convert variadic data to Boost PP data types for use by Boost PP. The library also enhances the Functionality of Boost PP tuple data. Installation is simply to take the boost and lib subfolders of the library and copy them to a Boost installation, preferable the trunk where support for variadic macros has been added in Boost config in the form of a BOOST_NO_VARIADIC_MACROS which is defined for compilers/versions which do NOT support variadic macros. To use the macros in the library, just "#include <boost/variadic_macro_data/VariadicMacroData.hpp>". Compilers which support variadic macros are gcc 3.0 and above and VC8 ( VS2005 ) and above among a few others. There is a discussion in the doc of why you might choose to use variadic macros rather than a Boost PP data type in a macro tailored for end-users. Comments, suggestions, and bug reports are welcome. Edward Diener

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[Locale] Stream manipulator bug
by Alexander Lamaison 09 Oct '10

09 Oct '10

The latest version of Boost.Locale is doing something wierd to stream manipulators. For example, the following code should print 63:2c:7f. If you uncomment the line that sets the global locale to use a boost::locale instance, it prints 990:440:127. It seems to be ignoring the std::hex manipulator and doing something strange with std::width. #include <iomanip> #include <iostream> #include <sstream> #include <string> #include <vector> #include <boost/locale.hpp> std::string hexify() { std::ostringstream hex_hash; hex_hash << std::hex << std::setfill('0'); unsigned int data[] = {99, 44, 127}; for(size_t i = 0; i < 3; ++i) { if (!hex_hash.str().empty()) hex_hash << ":"; hex_hash << std::setw(2) << data[i]; } return hex_hash.str(); } int main() { using boost::locale::generator; generator gen; //std::locale::global(gen("")); std::cout << hexify() << std::endl; } This is on Windows 7 with Boost.Locale compiled to only use the Win32 backend. Alex -- Easy SFTP for Windows Explorer (http://www.swish-sftp.org)

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[Review] Boost.Ratio
by joel falcou 09 Oct '10

09 Oct '10

So here is my review of Boost.Ratio *- What is your evaluation of the design?* It's a strictly (or at least as struct as possible) implementation of the standard proposal. Code is clear and easily followed. *- What is your evaluation of the implementation?* It's very OK and straightforward. I'll reiterate the question about providing MPL or Fusion adaptors as an optional features (unless I missed them :x) *- What is your evaluation of the documentation?* Good *- What is your evaluation of the potential usefulness of the library?* Ratio fills a gap in the MPl-like data type and enables new interesting design to be done. *- Did you try to use the library? With what compiler? Did you have any problems? * I tried it using gcc 4.4 and 4.5 and icc 11. No problem so far. *- How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? * I quickly glanced over the code as I knew it from its inception and followed it so I only had to look some new stuff. I tried some non trivial task , including some attempt at MPL like CT linear system solver using rational. boost.ratio proved itself useful in this task. *- Are you knowledgeable about the problem domain? * Yes. *- Do you think the library should be accepted as a Boost library?* Yes

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[Boost][Proto] Fw:[Spirit-general] Patch for compiling Karma without RTTI
by Bryce Lelbach 09 Oct '10

09 Oct '10

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Forwarding from the spirit-general mailing list. Begin forwarded message: Date: Fri, 08 Oct 2010 12:01:55 +0800 From: Joel de Guzman <joel(a)boost-consulting.com> To: spirit-general(a)lists.sourceforge.net Subject: Re: [Spirit-general] Patch for compiling Karma without RTTI On 10/8/2010 10:34 AM, Bryce Lelbach wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > Summary: > > 0x0.) There's a workaround header for compilers without > typeinfo/typeid in boost/detail/sp_typeinfo.hpp. It has a few macros > that uses real typeid/typeinfo if it exists, and the workaround if > not. The workaround was broken on GCC 4.5.1 and clang (rebuilt daily > from upstream trunk). I fixed the problem (static initialization > jazz). > > 0x1.) Spirit's hold_any uses typeinfo/typeid. I changed it to use > the aforementioned macros. > > 0x2.) Some debugging stuff in one proto file used RTTI. I changed > it to use the aforementioned macros. > > I haven't had a need for Qi/Lex yet. I'm currently putting the > finishing touches on the ariel driver. My intention is to use Qi for > my lightweight command line parsing needs, because it will be less > painful than spending half an hour browsing through LLVM doxygen to > figure out how their cl parser works. So, there might be another one > of these patches in the morning. > > Patch was generated via svn diff from the top of my local copy of the > Boost trunk (on Debian GNU/Linux). I suggest sending an email to the Boost mailing list non-spirit related patches (and accompanying explanations). We don't have control over those parts (e.g. proto and boost/detail/sp_typeinfo.hpp) Regards, - -- Joel de Guzman http://www.boostpro.com http://spirit.sf.net - ------------------------------------------------------------------------------ Beautiful is writing same markup. Internet Explorer 9 supports standards for HTML5, CSS3, SVG 1.1, ECMAScript5, and DOM L2 & L3. Spend less time writing and rewriting code and more time creating great experiences on the web. Be a part of the beta today. http://p.sf.net/sfu/beautyoftheweb _______________________________________________ Spirit-general mailing list Spirit-general(a)lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/spirit-general - -- Bryce Lelbach aka wash http://groups.google.com/group/ariel_devel -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iEYEARECAAYFAkyumQMACgkQO/fqqIuE2t63WwCg2lT+hIeoy9xISTU73PwRE/FD G9sAoNQwHDIMMPYO1GbDiWYP0lco/crH =iU+P -----END PGP SIGNATURE-----

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Re: [boost] [Spirit-general] construe_cast, call for interest and feedback
by Jeroen Habraken 07 Oct '10

07 Oct '10

On 7 October 2010 22:43, Aaron Graham <aaron(a)aarongraham.com> wrote: > I'm excited about construe_cast. I always liked the flexibility of > lexical_cast, but tend not to use it as much as I could because of its > performance relative to other mechanisms. > Does gcc still convert "23" at compile time if you disable builtins? > (-fno-builtin) > #include <boost/construe_cast.hpp> int main(int, char**) { return boost::construe_cast<int>("23"); } compiled using gcc 4.5.1, g++-4.5 test.cpp -o test -O3 -I . -I ../library/boost-trunk/ -fno-builtin will generate the following code: Dump of assembler code for function main: 0x0000000100000e20 <main+0>: push %rbp 0x0000000100000e21 <main+1>: mov $0x17,%eax 0x0000000100000e26 <main+6>: mov %rsp,%rbp 0x0000000100000e29 <main+9>: leaveq 0x0000000100000e2a <main+10>: retq 0x0000000100000e2b <main+11>: nopl 0x0(%rax,%rax,1) thus as you can see, it's still able to perform the optimization. Jeroen

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[Review] Formal Review of Proposed Boost.Ratio Library Starts TODAY
by Anthony Williams 07 Oct '10

07 Oct '10

Hi everyone, The review of Vicente Botet' Ratio library starts TODAY (October 2nd) and lasts until October 11th, 2010, unless an extension occurs. What is it? ======== Portable implementation of the C++0x Standard Library's compile-time rational arithmetic working on C++03 and C++0x compilers. See the current C++0x working draft at http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2010/n3126.pdf Boost.Ratio provides: * A class template, ratio, for specifying compile time rational constants such as 1/3 of a nanosecond or the number of inches per meter. ratio represents a compile time ratio of compile time constants with support for compile time arithmetic with overflow and division by zero protection * It provides a textual representation of boost::ratio<N, D> in the form of a std::basic_string. Other types such as boost::duration can use these strings to aid in their I/O. This library is header-only and is designed to be generic and useful in a lot of areas of math and numerics C++ programming, in particular it is absolutely needed for the proposed Boost.Chrono and Boost.Stopwatches libraries which are currently in the review queue. Getting the library ============= The latest version of this library may be downloaded from vault: http://www.boostpro.com/vault/index.php?action=downloadfile&filename=ratio.… SVN: http://svn.boost.org/svn/boost/sandbox/chrono (directories boost/ratio and libs/ratio) and the docs may be viewed here html: http://svn.boost.org/svn/boost/sandbox/chrono/libs/ratio/doc/html/index.html pdf: http://svn.boost.org/svn/boost/sandbox/chrono/libs/ratio/doc/ratio.pdf You can get all these information also (which should avoid some long links) from http://svn.boost.org/trac/boost/wiki/LibrariesUnderConstruction#Boost.Ratio It is worth noting that the tests included in the zip file are relatively sparse. Vicente has an extensive suite of tests licensed under the LLVM license. He has posted a message on the Boost Developers mailing list regarding the license requirements for tests (See http://thread.gmane.org/gmane.comp.lib.boost.devel/208978) and is awaiting the outcome of that discussion before making the tests available. Writing a review ================ If you feel this is an interesting library, then please submit your review to the developer list (preferably), or to the review manager. Here are some questions you might want to answer in your review: - 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 what compiler? 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? And finally, every review should answer this question: - Do you think the library should be accepted as a Boost library? Be sure to say this explicitly so that your other comments don't obscure your overall opinion. Anthony Review Manager for the proposed Boost.Ratio library -- Author of C++ Concurrency in Action http://www.stdthread.co.uk/book/ just::thread C++0x thread library http://www.stdthread.co.uk Just Software Solutions Ltd http://www.justsoftwaresolutions.co.uk 15 Carrallack Mews, St Just, Cornwall, TR19 7UL, UK. Company No. 5478976

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[Concept Check] ContiguousIterator
by joel falcou 07 Oct '10

07 Oct '10

Using BCC, s there any way to refine RandomAccessIterator so the cocnept captures the fact that the address of two consecutive value iterated over are contiguous in memory ? I can't get any proper expression to check for this in a proper way.

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[xpressive] Support for multi-capture and balancing groups
by Erik Rydgren 07 Oct '10

07 Oct '10

Hi! My company have been using pcre for a long while but there has been gripes about it only returning the last matched value from a capture group. Because of this I have been searching for a C++ regex engine that can handle the same stuff as the .NET implementation can do, to no avail. During my searches I've stumbled on several forum threads where others have been searching for the same thing but it doesn't seem to exist a regular expression library in C/C++ that handles both named captures and multicapture. Found boost.xpressive and it had almost everything we need. It's open source, fast, got flexible api and named captures. But alas, just as all other C and C++ based implementations I have found, it lacked multiple captures. So, I added it. On top of that I added support for balancing groups (http://blog.stevenlevithan.com/archives/balancing-groups) But the syntax for the pop capture and capture conditional is slightly different then the .NET version to better fit xpressive. Syntax for pop capture: dynamic: (?P<-name>stuff) static: (name -= stuff) Syntax for capture conditional: dynamic: (?P(name)stuff) static: (name &= stuff) There is no support for the (?<name-othername>stuff) construct. All captures made by a group is stored in sub_match::captures which is a vector of sub_match_capture objects. A sub_match_capture behaves like a stripped down sub_match. It can be put in an ostream and has a length and helper function for returning a string. The changes are in the vault and can be found here: http://tinyurl.com/3aak7mp It can be unpacked against trunk from 2010-10-02 or the 1.44.0 release. I've run the dynamic regression tests without errors and I have added some tests for the new functionality. The code it only tested on Visual Studio 2010 since I don't have access to any other compiler. Please give feedback on my changes since I would love to see them in an official release. Thanks in advance. Regards, Erik

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[fusion] for_each
by Christophe Henry 07 Oct '10

07 Oct '10

Hi, I have 2 fusion containers: a small vector (my_vec) and a bigger set (my_set). I want to overwrite the elements of the set with elements from the vector whenever they have the same type. Sounds simple: struct update { update(my_set_type& to_overwrite_):to_overwrite(to_overwrite_){} template<typename T> void operator()(T& elt) /*const?*/ { boost::fusion::at_key<T>(to_overwrite)=elt; } my_set_type& to_overwrite; }; boost::fusion::for_each(my_vec,update(my_set)); Except that this won't compile because the operator() is required to be const, which is sad, because it was very simple. This leaves me with the unattractive option of inverting the set and the vector inside update. Now, I iterate on the set's elements and overwrite them when found in the vector. This is unattractive because 1) the code gets really ugly 2) it could be slower (the set is bigger) and 3) it has a much bigger compile-time cost (I resorted to an enable_if of fusion::result_of::find and I make it short, it is actually much worse). I thought of using transform, but this will be slower as I will need to transform every element of the set, even for a vector of size 1. Am I missing something? If not, would it be possible to remove this constraint? Thanks, Christophe

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