February 2010 - Boost - lists.preview.boost.org

[BGL] Testing a graph for bipartiteness
by Matthias Walter 06 Mar '10

06 Mar '10

Hi, I'm working on a project where I need to determine whether a given graph is bipartite (possible yielding certificates for the two cases). As such a test can be perfectly implemented via BFS and visitor patterns, I wondered why there is no implementation in the BGL. Is there any reason or am I just to blind to find it? If I'm forced to write my own one, how about submitting it to BGL? best regards Matthias Walter

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[log] init methods and named parameters
by Michael Caisse 05 Mar '10

05 Mar '10

I've gotten a head start looking at the boost.log library that will be reviewed in a couple weeks. The utility methods utilize boost.parameter's named parameters. For example, boost::log::init_log_to_file. I would like to decide at runtime (via a config file) which set of parameters will listed. For example, rotation_size or rotation_interval or both. It is my first real use of boost.parameter so I may be missing something that is common knowledge. I don't see an easy way to do this. I thought maybe building a fusion sequence of parameters or something like that was the way to go... Looking for guidance. Thanks. michael -- ---------------------------------- Michael Caisse Object Modeling Designs www.objectmodelingdesigns.com

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[rfc] rcpp
by Ivan Sorokin 04 Mar '10

04 Mar '10

Hello! I have a small library that is intended for convenient and declarative resource wrappers creation. Read Documentation: http://rain.ifmo.ru/~sorokin/rcpp/doc/index.html Main Page: http://rain.ifmo.ru/~sorokin/rcpp/ Although this library is small I think it is useful. I think it is possible to use it in implementations of asio, filesystem and thread. **-- Ivan Sorokin

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[Filesystem V3] Filesystem Version 3 beta 1 available for download and comment
by Beman Dawes 03 Mar '10

03 Mar '10

The first beta release of Boost.Filesystem Version 3 is now available. The documentation can be viewed at http://mysite.verizon.net/beman/v3/index.htm Important differences from the prior version: http://mysite.verizon.net/beman/v3/v3.html The beta can be downloaded from the Boost vault. See http://www.boostpro.com/vault/index.php?&direction=0&order=&directory=Files… Installing the beta is described at http://mysite.verizon.net/beman/v3/install_distro.html I'm concerned about breaking existing code. While some workarounds have been provided already, I'd open to further suggestions as to how to mitigate code breakage. The tentative plan for integrating V3 into the boost release cycle involves several steps: * For the first boost release cycle, ship V2 as the default, but V3 is present and can be activated by users. * For an additional boost release cycle, ship V3 as the default, but V2 is present (but deprecated) and can be activated by users. * For the following boost release cycle, V2 is removed and no longer supported. The plan is to go through as many beta cycles as needed to reach stability. Although quite a bit of testing has already been done, this is definitely beta software that isn't ready yet for production use. Any comments appreciated. --Beman

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[iostreams] array and gzip_decompressor
by Nikolay Mladenov 01 Mar '10

01 Mar '10

Recently I came back to a source written some time ago, that was running then but it is not compiling now. the failing snippet is: typedef boost::iostreams::composite<boost::iostreams::gzip_decompressor, boost::iostreams::array_source> array_gzip_decompressor; boost::iostreams::gzip_decompressor filter; boost::iostreams::array_source source(&_storage[0], _storage.size()); array_gzip_decompressor dev(filter,source); boost::iostreams::stream_buffer<array_gzip_decompressor> ibuf(dev); the error is: > boost\iostreams\read.hpp(191) : error C2039: 'putback' : is not a member of 'boost::iostreams::detail::direct_adapter<Direct>' > with [ Direct=boost::iostreams::array_source ] It seems to me that gzip_decompressor requires peekable source, but array_source is not peekable. Is there another way I should be creating gzipped stream into memory? Or maybe the arrays could be made peekable? Thanks in advance, Nikolay Mladenov

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[ITL][Review] A late mini review
by Thomas Klimpel 01 Mar '10

01 Mar '10

> Please always state in your review, whether you think the > library should be accepted as a Boost library. ITL should be accepted as a Boost library. > - What is your evaluation of the design? I haven't spend sufficient time reviewing the library to be able to judge the design. At least, I haven't seen any obvious flaws during my short review. > - What is your evaluation of the implementation? I took a cursory look at all source (header) files, and they look nicely written. I took a cursory look at the directory structure, to verify that it follows boost conventions. It does so in general, but I was surprised to find a "libs/itl/build" folder, since I "know" that ITL is a headers only library. The content of the build folder also didn't make me happy (it's extremely "unportable"), but this is a completely different topic that has nothing to do with this specific library. The template meta programming in boost/itl/type_traits/* could follow MPL conventions more closely. > - What is your evaluation of the documentation? The documentation is nicely written. However, please don't invent new words like "aggrovering" or "unon". Please also try to avoid changing the meaning of existing words like "neutron". > - What is your evaluation of the potential usefulness of the library? The need to work with "interval sets" arises sufficiently frequently in "time based" and "geometry based" problem domains to warrant a library dedicated especially to this problem domain. (In my review of Boost.Polygon, I pointed out that interval set concepts were missing.) I have to admit that I haven't spend sufficient time evaluating ITL to be able to judge whether ITL is able to handle all these needs. > - Did you try to use the library? With what compiler? Did you have any problems? No, I didn't try to use the library. > - How much effort did you put into your evaluation? > A glance? A quick reading? In-depth study? Some month ago, I read through the documentation just for the pleasure it gave me, pondered a bit about the concept and looked at the BoostCon2009 slide show. I was certainly planning to do a proper review during the review period, but I was (and still am) occupied with other things. What I've done now while writing this review was just a glance. > - Are you knowledgeable about the problem domain? This is not important in this case, since I haven't spend enough time for the review anyway. Regards, Thomas P.S.: As I guessed from recent experience, the review period has just been extended. However, I decided to submit this mini review nevertheless. I may have a look at "I have to admit that I haven't spend sufficient time evaluating ITL to be able to judge whether ITL is able to handle all these needs." with respect to the issue raised by Phil Endecott in http://lists.boost.org/Archives/boost/2010/02/162198.php (and write about it in case I can make up my own opinion), because this seems to be an interesting question. Even so I want to thank Phil Endecott for his courage to bring up this issue, and I guess that he is right (in a certain sense), I think it is wiser to base my review only on my personal experiences and not on my judgment of whether Phil is right or wrong with respect to this issue.

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[numeric][intervall] msvc_rounding_control.hpp broken in 64 bit build.
by Juergen Hunold 01 Mar '10

01 Mar '10

Hi ! boost/numeric/interval/detail/msvc_rounding_control.hpp does not compile in x64 (64bit) build with (at least) msvc-9 The offending commit is: ------------------------------------------------------------------------ r59350 | marshall | 2010-01-29 19:01:34 +0100 (Fri, 29 Jan 2010) | 1 line Applied patches to fix #2512 and #2513 ------------------------------------------------------------------------ This does not show up in regression test because we don't have a test runner running a 64bit version of msvc. The compiler bails out on the x86 inline assembler introduced in that commit when running in 64bit mode. The simple patch is to fall back to the old behaviour using "rint" for target "x64": Index: msvc_rounding_control.hpp =================================================================== --- msvc_rounding_control.hpp (revision 59697) +++ msvc_rounding_control.hpp (working copy) @@ -25,7 +25,7 @@ namespace interval_lib { namespace detail { -#if BOOST_MSVC < 1400 +#if BOOST_MSVC < 1400 || defined(WIN64) extern "C" { double rint(double); } #else inline double rint(double x) I can apply this if necessary. Tested with msvc-9.0 I have not looked into the referenced tickets. Any (better) ideas ? Yours, Jürgen -- * Dipl.-Math. Jürgen Hunold ! Ingenieurgesellschaft für * voice: ++49 511 262926 57 ! Verkehrs- und Eisenbahnwesen mbH * fax : ++49 511 262926 99 ! Lister Straße 15 * juergen.hunold(a)ivembh.de ! www.ivembh.de * * Geschäftsführer: ! Sitz des Unternehmens: Hannover * Prof. Dr.-Ing. Thomas Siefer ! Amtsgericht Hannover, HRB 56965 * PD Dr.-Ing. Alfons Radtke !

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ptr_container move support
by Zachary Turner 01 Mar '10

01 Mar '10

The collections in ptr_container don't seem to support move constructors. All the recent compilers support r-value refs, has there been any discussion of adding support for this? Zach

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[Serialization] extended_type_info.hpp
by fab 01 Mar '10

01 Mar '10

Hi, With boost 1.42.0, when I use BOOST_CLASS_EXPORT, I always need to include extended_type_info.hpp to resolve this error : xxx.hpp:153: error: 'guid_defined' is not a template xxx.hpp:153: error: explicit specialization of non-template 'boost::serialization::guid_defined' xxx.hpp:153: error: expected initializer before '<' token xxx.hpp:153: warning: 'boost::archive::detail::<unnamed>::init_guid<MyClass>::g' defined but not used Maybe extended_type_info.hpp can be included in export.hpp ? Fabien Castan

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Setting up a test suite
by Marshall Clow 28 Feb '10

28 Feb '10

I've got two implementations of the same functionality I want to compare with Boost.Test. One's in C++ (natch), the other in Python. Currently, they're packaged as tools that take a file as a parameter, and write results to stdout. Call them "dumpinfo.cpp" and "dumpinfo.py". How would I use Boost.Test to compare the output of these tools for a selection of sample tests? Conceptually, I would do: g++ -o dumpInfo dumpInfo.cpp ./dumpInfo testFile > /tmp/c.out python dumpInfo.py testFile > /tmp/py.out diff -q /tmp/c.out /tmp/py.out But how to do this using Boost.Test? Notes: * I have several (many) test files. It would be nice to list these files in a Jamfile. * There are a couple bugs in the Python packages I am using. I need to mark some of them as "expected failures" Thanks in advance! -- Marshall

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