July 2007 - Boost-users - lists.preview.boost.org

[lexical_cast] C4701 local variable 'result' may be used without having been initialized
by Berny Cantos 12 Jul '07

12 Jul '07

Hi, I'm using boost::lexical_cast often in my application, but then I use it to convert strings to integral types and the compiler (MSVC 7.1) threw me a warning: C4701: local variable 'result' may be used without having been initialized Looking at lexical_cast implementation I found this template<typename Target, typename Source> Target lexical_cast(Source arg) { detail::lexical_stream<Target, Source> interpreter; // THIS is guilty of not been initialized Target result; if(!(interpreter << arg && interpreter >> result)) throw_exception(bad_lexical_cast(typeid(Source), typeid(Target))); return result; } I was asking myself... why not use Fernando Cacciola's boost::value_initialized to avoid these warnings? template<typename Target, typename Source> Target lexical_cast(Source arg) { detail::lexical_stream<Target, Source> interpreter; // This can't raise any uninitialized related warning boost::value_initialized<Target> result; if(!(interpreter << arg && interpreter >> get(result))) // Must use get idiom throw_exception(bad_lexical_cast(typeid(Source), typeid(Target))); return get(result); // Must use get idiom } Somebody can explain me this? Is this warning a compiler issue? Thanks in advance Berny Cantos AZ Interactive SL

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[1.34.1] Release Candidate 2
by Thomas Witt 12 Jul '07

12 Jul '07

Hi, The 1.34.1 release candidate 2 is now available from http://www.boost.org/release/ please give it a try and report any problems to the developer list or directly to me. Unless a major issue surfaces this will ship as 1.34.1 on July 13th. Thanks Thomas -- Thomas Witt witt(a)acm.org

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[Boost.Lambda] Can't bind (do a partial application on) basic operands
by Kirit Sælensminde 11 Jul '07

11 Jul '07

I'm trying to really understand the limits of what can be done in C++ with Boost.Function and Boost.Lambda by implementing a number of functional programming idioms in C++. I've done a few fairly complicated things, but seem to have run into a problem with a really basic one. I just want to do a partial application on some basic operands. This is what I'm trying to do: boost::function< int( int ) > increment( boost::lambda::_1 + 1 ); This gives an error that operator + isn't defined for the Boost placeholder type. If I add the following it works: template< typename V > V add( V l, V r ) { return l + r; } template< typename S > boost::function< S ( S ) > operator +( const boost::lambda::placeholder1_type, S s ) { return boost::lambda::bind( add< S >, boost::lambda::_1, s ); } I guess there's a huge number of these that could (should?) be added. Is this an oversight, or am I doing things with the library that I'm not meant to do? I'm using MSVC 7.1 and Boost 1.34.0 release candidate. K

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Building Boost on Solaris 10.
by Sabyasachi Nath 11 Jul '07

11 Jul '07

Hi Everybody, I am new with Boost. I am facing the following problem while building Boost 1.34.0. My system is Solaris 10. Compiler :- -bash-3.00$ CC -V CC: Sun C++ 5.8 Patch 121017-10 2007/02/21 ************** >From my $BOOST_ROOT location I started my building and installation as follows. ======== ============ -bash-3.00$ ./configure -- prefix=/disk2/sabyasachi/Boost_1.34.0/Build/boost_1_34_0 --with-libraries=all -n Building Boost.Jam with toolset sunpro... tools/jam/src/bin.solaris/bjam ./configure: python: not found -n Unicode/ICU support for Boost.Regex?... /usr Generating Boost.Build configuration in user-config.jam... Generating Makefile... ============== -bash-3.00$ make install ./tools/jam/src/bin.solaris/bjam -sICU_PATH=/usr --user-config=user-config.jam - -prefix=/disk2/sabyasachi/Boost_1.34.0/Build/boost_1_34_0 --exec- prefix=/disk2/sabyasachi/Boost_1.34.0/Build/boost_1_34_0 -- libdir=/disk2/sabyasachi/Boost_1.34.0/Build/boost_1_34_0/lib -- includedir=/disk2/sabyasachi/Boost_1.34.0/Build/boost_1_34_0/include install sunpro.jam: No such file or directory /disk2/sabyasachi/Boost_1.34.0/Build/boost_1_34_0/tools/build/v2/build/toolset.j am:27: in toolset.using rule sunpro.init unknown in module toolset. /disk2/sabyasachi/Boost_1.34.0/Build/boost_1_34_0/tools/build/v2/build/project.j am:825: in using user-config.jam:5: in modules.load /disk2/sabyasachi/Boost_1.34.0/Build/boost_1_34_0/tools/build/v2/build- system.jam:138: in load /disk2/sabyasachi/Boost_1.34.0/Build/boost_1_34_0/tools/build/v2/kernel/modules. jam:261: in import /disk2/sabyasachi/Boost_1.34.0/Build/boost_1_34_0/tools/build/v2/kernel/bootstra p.jam:132: in boost-build /disk2/sabyasachi/Boost_1.34.0/Build/boost_1_34_0/boost-build.jam:9: in module scope Not all Boost libraries built properly. -bash-3.00$ ================ Can anybody please sort out what the problem is? Thanks in advance. Sabyasachi..

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composing with boost::bind
by Pieter Op de Beeck 11 Jul '07

11 Jul '07

Hi, I would like to accomplish the following: "bind a functor to a reference and compose this with another functor". Ultimately I would like to use this composition with the reference embedded in it. If I write it like this: functor_type h = bind(f, bind(g, ref(b))); it works alright. However, in my situation the binding of g is done somewhere else in the program, so have: functor_type temp = bind(g, ref(b)); ... functor_type h = bind(f, temp); Sadly enough this does not appear to work. I don't have a reference to b in h(). I'm sure bind works the way it was intended. I'm more interested in whether you guys now how to achieve the effect I'm trying to achieve? Much appreciated, Pieter. Some additional context: using namespace boost; typedef function<bool ()> functor_type; struct f { bool operator()(bool b) { return !b; } }; struct g { bool operator()(bool b) { return b; } }; bool b; The effect I'm trying to achieve: b = true; b = h(); // produces !b, so b is now false b = h(); // produces !b, so b is now true (in the second case above this would produce false again because there appears to be no reference to b in h()) Pieter Op de Beeck www.visysglobal.com

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Boost with threadpool
by Gopalan, Srinivasan (MLITS) 11 Jul '07

11 Jul '07

Hi all, I would like to know whether any version of boost uses threadpool. Also there is a separate threadpool package. I would like to know how to link this package with boost. Thanks, Srini. -------------------------------------------------------- This message w/attachments (message) may be privileged, confidential or proprietary, and if you are not an intended recipient, please notify the sender, do not use or share it and delete it. Unless specifically indicated, this message is not an offer to sell or a solicitation of any investment products or other financial product or service, an official confirmation of any transaction, or an official statement of Merrill Lynch. Subject to applicable law, Merrill Lynch may monitor, review and retain e-communications (EC) traveling through its networks/systems. The laws of the country of each sender/recipient may impact the handling of EC, and EC may be archived, supervised and produced in countries other than the country in which you are located. This message cannot be guaranteed to be secure or error-free. This message is subject to terms available at the following link: http://www.ml.com/e-communications_terms/. By messaging with Merrill Lynch you consent to the foregoing. --------------------------------------------------------

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[IBD] Weekly news: 2007-07-04 to 2007-07-10
by Matias Capeletto 11 Jul '07

11 Jul '07

================================================== Hi Boost, Once a week, we will send you a brief of our work for the Improving Boost Docs project. We need more hands, join us! We are waiting you on the boost-docs list. Project Wiki: http://svn.boost.org/trac/boost/wiki/ImprovingBoostDocs RSS news feed: http://beta.boost.org/development/ibd_news.rss Community Blog: http://improving-boost-docs.blogspot.com ================================================== 2007-07-10 ------------------------------------------------------------------------------------- * Jake joins the community Blog He writes: I feel that it would be helpful if there was a little bit of standardization in the layout/content of the documentation. A lot of the documentation implements similar ideas (one minute tutorials, introductions, reference sections), but each individual libraries documentation has the earmarks of the authors. more... http://tinyurl.com/3btnae 2007-07-09 ------------------------------------------------------------------------------------- * Resources Section added to the Community Blog "The Blog is a one-stop shop" -- Stjepan more... http://improving-boost-docs.blogspot.com 2007-07-08 ------------------------------------------------------------------------------------- * Two proof-readers join the project Thanks Paul Giaccone and Jake Voytko for jumping in. more... http://tinyurl.com/2optqg * Boost community feedback on our objectives Since we want to build a long term subcommunity which main purpose is to continuously improve the quality of Boost documentation, we would like that our main directives be aligned with the Boost community as a whole. more... http://tinyurl.com/3czjfn 2007-07-07 ------------------------------------------------------------------------------------- * Resources Section added to the Wiki At IBD we use several open source tools to organize our efforts. In this section the purpose of each resource is explained. When possible, IBD resources will be interlinked and share a common look and feel allowing a consistent experience for both users and developers. more... http://tinyurl.com/2uxfut#Resources 2007-07-06 ------------------------------------------------------------------------------------- * Help request, A woman's point of view Is there any female Booster willing to help us? more... http://tinyurl.com/2om8ek * Stjepan joins the community Blog He add a post about his experience transalting smart_ptr docs. more... http://tinyurl.com/3d3r93 * Help request, Python programmers There are two specific projects that need Python programmers: 1) http://svn.boost.org/trac/boost/wiki/BoostSpecificWikiMacros 2) http://svn.boost.org/trac/boost/wiki/QuickbookWikiProcessor more... http://tinyurl.com/2lqe2p * Two testers join the project Stuart help request was answered by Chun Ping Wang and Marco. Welcome to IBD! more... http://tinyurl.com/323uf5 2007-07-05 ------------------------------------------------------------------------------------- * IBD RSS news feed The IBD news feed consists of formal announces about the things going on in the project, they are very short and direct headlines. Some of the common subjects are new members, new subprojects, help requests and completed translation. more... http://beta.boost.org/development/ibd_news.rss * New Community Blog A record of the things that happens behind the scenes, our next objectives and the social and philosophical aspects of IBD. more... http://improving-boost-docs.blogspot.com 2007-07-04 ------------------------------------------------------------------------------------- * Translation of Boost.Boostbook completed We have translated boostbook docs to quickbook and add a sections about boosbook specific HTML params. more... http://tinyurl.com/32zgtm * Our team mascot Give a warm welcome to Mafalda, our team mascot. She is a English Springer Spaniel from Argentina, currently living with Matias. Mafalda is helping him with the project Wiki page. She just barks once in a while, but that is a lot. more... http://tinyurl.com/2uxfut#team_mascot * Stuart Dootsoon's help request for the Browser testing project We need more testers to cover all the possible browsers and platforms combinations. more... http://tinyurl.com/2q6csw

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Re: [Boost-users] problem message bis new
by question boost 11 Jul '07

11 Jul '07

They say: step 1 run buil.bat step 2 set BOOST_ROOT and BOOST_BUILD_PATH. I've runed build.bat and I have set BOOST_ROOT and BOOST_BUILD_PATH. It's not the right thing to do. My question is (only for a programmer who has the response): What is the right thing to do (step 1,step 2, step3, step4, step5, step 6 and so on)? Thank You > From: ghost(a)cs.msu.su> To: boost-users(a)lists.boost.org> Date: Wed, 11 Jul 2007 11:34:16 +0400> Subject: Re: [Boost-users] problem message bis new> > question boost wrote:> > > > > Hi,> > I repeat: the version of Boost is not the solution of the problem message.> > What must I do now after the run of build.bat and the set of the two main> > variables?> > Let me start with some trivial aspects.> > 1. Reposting a question every day is not polite. There's no guaranteed> 24-hour response time here.> > 2. It would be more polite if you messages had your real name in> the "From" field. I presume "question boost" is not your real name.> > As for your question, you don't seem to have followed the getting started document.> Setting BOOST_ROOT and BOOST_BUILD_PATH without building boost is not> going to have any effect whatsoever.> > - Volodya> > _______________________________________________> Boost-users mailing list> Boost-users(a)lists.boost.org> http://lists.boost.org/mailman/listinfo.cgi/boost-users _________________________________________________________________ Besoin d'un e-mail ? Créez gratuitement un compte Windows Live Hotmail et gagnez du temps avec l'interface à la Outlook ! http://www.windowslive.fr/hotmail/default.asp

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Weird compile error on VS .NET 2003 with boost::property
by gast128 11 Jul '07

11 Jul '07

Dear all, we upgraded yesterday to boost 1.34 but now ran in a weird compile error on vstudio 2003 (sp1) when using boost properties (or indirect through use of graph) and an enumerate enlosed by a namespace. E.g.: namespace Bla { struct Dummy {}; enum Foo { eFoo }; } void Example3() { boost::property<int, Bla::Dummy> prop1; //ok boost::property<int, Bla::Foo> prop2; //error } It gives something like: error C2065: 'Foo' : undeclared identifier. It chokes on the line: template <class Tag, class T, class Base = no_property> struct property : public Base { ... #if BOOST_WORKAROUND (__GNUC__, < 3) property() { } #else property() : m_value() { } <---- #endif Anyone an idea? Wkr, me

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problem message bis new
by question boost 11 Jul '07

11 Jul '07

Hi, I repeat: the version of Boost is not the solution of the problem message. What must I do now after the run of build.bat and the set of the two main variables? Thank You _________________________________________________________________ Windows Live Messenger vous offre 30 nouvelles émoticônes gratuites, installées directement dans votre Messenger ! http://www.emoticones-messenger.fr/

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