- Boost-users - lists.boost.org

Using mpl::remove with template paramter
by spider tong 25 Oct '07

25 Oct '07

Hi all, I'm trying to use mpl::remove to do some processing with a template parameter, like this template<typename T0, typename T1=null_type, ... typename Tn=null_type> struct my_class { typedef mpl::vector<T0, T1,...Tn> my_vector; typedef mpl::remove<my_vector, null_type>::type my_non_vector; //failed here }; Compiler report that my_vector is not derive from my_class<T0, T1,..Tn>. It seems that 'remove' would test the sequence at once, and my_vector still un_known yet, so it fails, is this guess right? //-------------------------------------------------------------------------- And I've tried this fusion too: teypdef vector<Class1, Class2, null_type, null_type> vec; vec v; fusion::for_each<v, print>; it seems that it iterate 4 times, not 2, even size(vec) return 2. It seems only evaluate will skip null_type, iterate will go through all member, is my guess right? Best Regards Spider

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Re: [Boost-users] Request to know about "dynamic expression evaluation"
by Borse, Ganesh 25 Oct '07

25 Oct '07

Hi, You recommended checking the "expression templates". However, expression templates (xpressive) provides the means of parsing the input expressions in to tokens. It does not have the support for evaluating these expressions. --- please correct me if I'm wrong. Thanks, Ganesh > _____________________________________________ > From: boost-users-bounces(a)lists.boost.org [mailto:boost-users-bounces@lists.boost.org <mailto:boost-users-bounces@lists.boost.org> ] On Behalf Of boost-users-request(a)lists.boost.org > Sent: 24 October 2007 02:29 > To: boost-users(a)lists.boost.org > Subject: Boost-users Digest, Vol 1428, Issue 3 > > Send Boost-users mailing list submissions to > boost-users(a)lists.boost.org > > To subscribe or unsubscribe via the World Wide Web, visit > http://lists.boost.org/mailman/listinfo.cgi/boost-users <http://lists.boost.org/mailman/listinfo.cgi/boost-users> > or, via email, send a message with subject or body 'help' to > boost-users-request(a)lists.boost.org > > You can reach the person managing the list at > boost-users-owner(a)lists.boost.org > > When replying, please edit your Subject line so it is more specific than "Re: Contents of Boost-users digest..." > > > Today's Topics: > > 1. Re: Request to know about "dynamic expression evaluation" > (Robert Ramey) > 2. seeding a boost::random number generator...? (Graham Reitz) > 3. Thread Library Problem (Andres Herrera) > 4. boost::serialization Is there any way to get rid of compiler > warnings(C4103, ...) on VC++ 2005? (Oleg Udovenko) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Tue, 23 Oct 2007 09:15:17 -0700 > From: "Robert Ramey" <ramey(a)rrsd.com> > Subject: Re: [Boost-users] Request to know about "dynamic expression > evaluation" > To: boost-users(a)lists.boost.org > Message-ID: <ffl6mi$25v$1(a)ger.gmane.org> > Content-Type: text/plain; charset="iso-8859-1" > > Request to know about "dynamic expression evaluation"Look for "expression templates" > > Robert Ramey > "Borse, Ganesh" <ganesh.borse(a)credit-suisse.com> wrote in message news:F444CAE5E62A714C9F45AA292785BED327C3BE87@esng11p33001.sg.csfb.com <news:F444CAE5E62A714C9F45AA292785BED327C3BE87@esng11p33001.sg.csfb.com> ... > Hi, > I would like to perform the dynamic expression evaluation in my c++ application. > The dynamic expressions are like the SQL queries. > Since the expressions could be nested & hence the parsing & evaluation of such expressions is reducing the performance of my application. > > May I please know, whether BOOST provides a support for such dynamic expression evaluation in C++? > Please guide. > > Thanks in advance for the guidance. > > Regards, > Ganesh > > > ============================================================================== > Please access the attached hyperlink for an important electronic communications disclaimer: > > http://www.credit-suisse.com/legal/en/disclaimer_email_ib.html <http://www.credit-suisse.com/legal/en/disclaimer_email_ib.html> > ============================================================================== > > > > ------------------------------------------------------------------------------ > > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users <http://lists.boost.org/mailman/listinfo.cgi/boost-users> >

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The arrangement of a boost program
by question boost 25 Oct '07

25 Oct '07

Hi, 1 My program under Code Blocks makes use of Boost. The arrangement of my files is the following: in the directory of the source files of my program there is the directory "boost" containing the following directories: "filesystem", "config", "iterator","range","detail", "mpl", "preprocessor", "tools" and the file boost-build.jam. 2 The file that makes use of boost in my project contains the following lines: #include <string> using namespace std; #include "boost\filesystem\path.hpp" #include "boost\filesystem\operations.hpp" using namespace boost::filesystem; 3 At compilation I get the message :"boost/preprocessor/config/config.hpp" no such file or directory and several other similar messages about other files of the same directory and about other files of the "mpl" directory. I've followed all the instructions here http://www.boost.org/doc/html/jam/building.html and here http://www.boost.org/doc/html/bbv2/installation.html At end of step 4 of http://www.boost.org/doc/html/bbv2/installation.html, the problem at compilation remains the same. Thank you for your response. David _________________________________________________________________ Retrouvez Windows Live Messenger sur votre mobile ! http://www.messengersurvotremobile.com

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Compiling 1.34.1 on OpenSUSE 10.3
by Ruediger Berlich 25 Oct '07

25 Oct '07

Hi there, OpenSUSE 10.3 is still delivered with Boost 1.33.1 . Hence I've downloaded Boost 1.34.1 and tried to compile it. I ran the configure script and then make. The resulting bjam immediately dies with an error: ./tools/jam/src/bin.linuxx86/bjam --user-config=user-config.jam /bin/sh: line 1: 2090 Speicherzugriffsfehler ./tools/jam/src/bin.linuxx86/bjam --user-config=user-config.jam "Speicherzugriffsfehler" means "memory access violation". This is on a Pentium-D dual-core system (4GB main memory) running with a 32-bit Linux kernel 2.6.22, g++ 4.2.1 . Does anyone have experience with this constellation ? Compilation of 1.34 worked fine on OpenSUSE 10.2 . Thanks and best regards, Ruediger

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[boost-users] anyways to flatten a stl container.
by chun ping wang 24 Oct '07

24 Oct '07

Is their some kind of method to flatten a stl container... example [[1, 4], [a,b, c], [b, [e]] ] becomes [1, 4, a, b, c, b, e]

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Question about versioning of serialization
by Fred Lupien 24 Oct '07

24 Oct '07

Hello, we are currently implementing serialization versioning using boost and I am curious to know if their is a way to support a changing class hierarchy. Let's say C derives from A for a while and then a change requires C to derive from B instead, which derives from A. Is it possible to support such a change provided we know what default values are needed for the new class? I tried and even if don't serialize anything in class C I get stream errors because I believe boost saves some base info for each class. When it tries to reload those value from a old stream, obviously it desynchronizes it because the values are not in the stream. So is their a way around this? Also is it possible to support the removal of a class. If, for exemple C derives from B which in turn derives from A and suddenly B is removed. Is their a way to deal with this without invalidating all previously saved data? Thank you for your help! -- Frédérick Martel-Lupien Étudiant en Génie Informatique Université de Sherbrooke fred.lupien(a)gmail.com

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dereferencing type-punned pointer in function_base under gcc-4.3
by Benoit Hudson 24 Oct '07

24 Oct '07

I'm trying to make sure my code compiles under gcc-4.3 before that compiler comes out. I'm currently stuck on an error it reports in boost, version 1.34.1 (which I downloaded seconds ago; error was also present in 1.34.0): In file included from ../boost/function/detail/prologue.hpp:16, from ../boost/function.hpp:22, from ../boost/iterator/transform_iterator.hpp:10, from [my code]: ../boost/function/function_base.hpp: In member function 'const std::type_info& boost::function_base::target_type() const': ../boost/function/function_base.hpp:485: error: dereferencing type-punned pointer will break strict-aliasing rules I don't understand how there's any type-punning going on at line 485, although to my untrained eye it looks a lot like it's returning a ref to a temporary. A couple lines later looks only very slightly fishier, but still shouldn't be breaking any aliasing rules. So I leave it to the experts to figure out what's going on here. -- Benoît

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installation on Borland Developer Studio 2006 (C++Builder)
by Harald Wolf - G. Ulmer Automation GbmH 24 Oct '07

24 Oct '07

Hi, how do i install boost with the BSD2006? The installer package seems not to work: ------my first try was------------------------------------------------------ #include "boost/date_time/gregorian/gregorian.hpp" //include all types plus i/o ... ... ---------------------------------------------------------------------------- - i get: [Linker Fataler Fehler] Fatal: Datei 'LIBBOOST_DATE_TIME-BCB-MT-D-1_34_1.LIB' kann nicht geöffnet werden since the C:\Programme\Borland\BDS\4.0\include\boost\boost_1_34_1\lib directory only has *vc* files. So i downloaded the: boost_1_34_1.zip BUT here i have to build the LIBs and i'm a C++ Newbiew! How do i build the Libs? PLEASE HELP!

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[program_options] Translating messages to another language
by Pavel Syomin 24 Oct '07

24 Oct '07

Hi to all! I am writing some application that uses program_options. This application interacts with user using non-english language. Is there any way to translate "what" messages from exceptions to another language? At now I found only one way (rather hack :) ): static void store(const basic_parsed_options<char> &options, variables_map &variables) { try { program_options::store(options, variables); } catch(unknown_option &error) { const char *what = error.what(); static const char prefix[] = "unknown option "; if(!strncmp(what, prefix, sizeof(prefix) - 1)) throw logic_error("Неизвестная опция: " + string(what + sizeof(prefix) - 1)); throw logic_error("Неверный формат командной строки"); } } Another way is to redefine function invalid_command_line_syntax::error_message(), but in such case we can translate only some messages.

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error2632:__int64 problem
by mmoges 24 Oct '07

24 Oct '07

Hi All, I am not sure if this issue has been dealt with already in this forum. But I couldn't find satisfactory answer on the Net. I am using Boost in an application that is working perfectly fine. I had to modify the application in a number of ways and I copied it to a different folder, and when I try to build it, it complains with errors and warnings that have never occured with the orignal application. Please find the error report below: c:\Boost\include\boost-1_33_1\boost\cstdint.hpp(304) : error C2632: '__int64' followed by '__int64' is illegal c:\Boost\include\boost-1_33_1\boost\cstdint.hpp(304) : warning C4091: 'typedef ' : ignored on left of '__int64' when no variable is declared c:\Boost\include\boost-1_33_1\boost\cstdint.hpp(307) : warning C4114: same type qualifier used more than once c:\Boost\include\boost-1_33_1\boost\cstdint.hpp(307) : error C2632: '__int64' followed by '__int64' is illegal c:\Boost\include\boost-1_33_1\boost\cstdint.hpp(307) : warning C4091: 'typedef ' : ignored on left of 'unsigned __int64' when no variable is declared c:\Program Files\Microsoft Visual Studio .NET 2003\Vc7\include\xlocmon(231) : fatal error C1903: unable to recover from previous error(s); stopping compilation I am a bit puzzled by this problem. I really appreciate any help. Thank you in advance. Best regards, Metty __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com

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