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

[regex] how to search backward?
by Armel Asselin 21 May '07

21 May '07

Hello all, i'm trying to search a regular expression backward. I use iterators. I suspect that i should use something like that, but i could not find documentation confirming: while (pos != start) { if (boost::regex_search (start, end, results, regex, ::regex_constants::match_continuous)) // it's ok; --start; } Is it the right idea? (using macth_continuous?) Regards Armel

1 0

Submitting compiler bugs to Microsoft (was: Converting loop to using boost::lambda wherecontainers has boost::shared_ptrs)
by Peter Dulimov 21 May '07

21 May '07

> -----Original Message----- > From: boost-users-bounces(a)lists.boost.org > [mailto:boost-users-bounces@lists.boost.org] On Behalf Of > Christian Henning > Sent: Sunday, 20 May 2007 8:41 AM > To: boost-users(a)lists.boost.org > Subject: Re: [Boost-users] Converting loop to using > boost::lambda wherecontainers has boost::shared_ptrs > > > > > I am glad to know I still the have skill of breaking compilers. :) > > > Well, I seem to have similar skills. The code below crashes my > compiler ( VC7.1 SP 1), as well. > > > void print( const std::string& s ) > { > std::cout << s; > } > > int main ( int, char** ) > { > typedef boost::shared_ptr<A> A_ptr_t; > typedef boost::shared_ptr<D> D_ptr_t; > > typedef std::vector < boost::shared_ptr<Base> > Data_t; > Data_t m_data; > > A_ptr_t a ( new A ( 50 ) ); > D_ptr_t d ( new D ( 30 ) ); > > m_data.push_back ( a ); > m_data.push_back ( d ); > > boost::uint32_t indent_value = 4; > > // this works > boost::bind( &print > , boost::bind( &Base::to_String > , A_ptr_t( new A( 5 ) ) > , indent_value ))(); > > // this doesn't work - ICE > std::for_each ( m_data.begin(), > m_data.end(), > boost::bind( &print > , boost::bind( &Base::to_String > , boost::bind::_1 > , indent_value ))); > > return 0; > } > > I know this is not the solution. I'm still using a seperate function > print() for outputting. I will keep trying to solve that one. > > On the other hand it would be nice if boost::bind comes some handy > function like the print(). Just a thought. > > Christian To post a bug report on Microsoft Visual Studio, you need to register (with Microsoft Passport, ie., hotmail style user account). Go to http://connect.microsoft.com, log in or register, and then navigate to https://connect.microsoft.com/feedback/default.aspx?SiteID=210&wa=wsigni n1.0 You need to search feedback before you can post a new bug. Regards, Peter. Warning: Copyright ResMed. Where the contents of this email and/or attachment includes materials prepared by ResMed, the use of those materials is subject exclusively to the conditions of engagement between ResMed and the intended recipient. This communication is confidential and may contain legally privileged information. By the use of email over the Internet or other communication systems, ResMed is not waiving either confidentiality of, or legal privilege in,the content of the email and of any attachments. If the recipient of this message is not the intended addressee, please call ResMed immediately on +61 2 8884 1000 Sydney, Australia.

4 3

[Multiindex] Const_mem_fun from base class
by Francesco Biscani 20 May '07

20 May '07

Hello, I get an error when I'm trying to use a const member function in a multi-index container, as a template parameter for indexed_by<>. This const member function comes from a base class, from which the class contained in the multiindex container is derived. The error is the following: /home/yardbird/documenti/work/prog/piranha/pyranha/Gsp/../../src/polynomial.h:41: error: could not convert template argument ‘&piranha::base_monomial_gmp_array<piranha::double_cf>::get_degree’ to ‘int (piranha::monomial_gmp_array<piranha::double_cf>::*)()const’ The member function is named "get_degree", and returns an integer. The base class is "base_monomial_gmp_array", the derived class is, unsurprisingly, "monomial_gmp_array". If I "lift" this function to the derived class, by re-defining it there, the problem disappears. I have a hunch that probably with some clever typedef or some static_cast wizardy this could be resolved, however my experiments have not resolved anything yet. Does anyone have an idea on how to proceed? Thanks in advance, Francesco Biscani.

2 1

poisson_distribution gives false results for high means
by Thibauld Nion 20 May '07

20 May '07

Hi, I'm using the boost/random library in a research project and really appreciate it, but I recently came across an annoying problem with the poisson_distribution. When instanciated with a relatively high expected mean (it happened for mean>10,000) the results given by this distribution is arbitrarily false. Actually the algorithm uses a comparison with exp(- mean) which I guess explains it all. Depending on the computer's precision this can be 'equal' to zero for relatively low values of 'mean'. Hence the random variables generated with the help of this distribution clearly do not follow a poisson distribution when the mean is too high. Of course a clever and careful user (unlike me) would not have fallen on this, but I thought it was worse mentionning -- especially since a well known workaround consists in using a normal distribution when 'mean' is 'high' (>100 usually does it...). Also, maybe a short notice of this problem could be made in the distribution's documentation ? Regards, Thibauld

1 0

Re: [Boost-users] [Serialization] purpose of GUID
by Ingo Nolden 20 May '07

20 May '07

Hi, I am a bit confused about the purpose of GUID. My understanding was, that it is a user defined id for a class, so that the serialization mechanism knows what types to instanciate on load. I somehow assumed it to be a replacement (or equivalent) of the numbers in the class_id attributes. by inserting: BOOST_CLASS_EXPORT_GUID( bus_schedule, "BusSchedule" ); I'd expected to find something like: <schedule class_id="BusSchedule" in the xml file, but I get only: <schedule class_id="1" I know that another purpose of the BOOST_CLASS_EXPORT family of macros is to instanciate the <Archive, T*> pairs, but what is the "BusSchedule" string then for. If my assumption was right, where do I have to place the macros exactly then. I tried at the end of the header with the classes. I then tried at the beginning, after the includes. That didn't work unless I forward declared the classes (no surprise really). Also, is there some docs/tutorials/further reading on xml archives. I am probably going to make my own archive, and need to understand more about the mechanism. Thanks for your help, Ingo

2 6

segfault in std::num_put when using boost::format and a boost::uint32_t as an argument.
by Stephen Torri 19 May '07

19 May '07

I am difficulty determining the location of the segfault in the following code: boost::uint32_t reserve_length = 0; std::ifstream file_handle_ref ( name.c_str(), std::ios::binary | std::ios::in ); if ( ! file_handle_ref.is_open() ) // Expecting result of is_open() to be true { std::cerr << "Error opening " << name << std::endl; std::cerr << " " << strerror(errno) << std::endl; std::cerr << boost::format("Exception throw in %s at line %d") % __FILE__ % __LINE__ << std::endl; throw errors::IO_Exception (errors::IO_Exception::FATAL_IO_ERROR); } file_handle_ref.seekg( 0, std::ios::end ); reserve_length = file_handle_ref.tellg(); std::cout << "Reserve length = " << reserve_length << std::endl; <SEGFAULT> std::cout << boost::format ("reserve_length (method 1) = %d") % reserve_length << std::endl; </SEGFAULT> ==452== Invalid read of size 4 ==452== at 0x480228C3: std::ostreambuf_iterator<char, std::char_traits<char> > std::num_put<char, std::ostreambuf_iterator<char, std::char_traits<char> > >::_M_insert_int<unsigned long>(std::ostreambuf_iterator<char, std::char_traits<char> >, std::ios_base&, char, unsigned long) const (in /usr/lib/libstdc++.so.6.0.8) ==452== by 0x48022BAF: std::num_put<char, std::ostreambuf_iterator<char, std::char_traits<char> > >::do_put(std::ostreambuf_iterator<char, std::char_traits<char> >, std::ios_base&, char, unsigned long) const (in /usr/lib/libstdc++.so.6.0.8) ==452== by 0x4802B63C: std::ostream::operator<<(unsigned) (in /usr/lib/libstdc++.so.6.0.8) ==452== by 0x4197E59: void boost::io::detail::put_last<char, std::char_traits<char>, unsigned>(std::basic_ostream<char, std::char_traits<char> >&, unsigned&) (feed_args.hpp:113) ==452== by 0x4197F85: void boost::io::detail::put<char, std::char_traits<char>, std::allocator<char>, unsigned&>(unsigned&, boost::io::detail::format_item<char, std::char_traits<char>, std::allocator<char> > const&, boost::basic_format<char, std::char_traits<char>, std::allocator<char> >::string_type&, std::char_traits<char>::internal_streambuf_t&, std::locale*) (feed_args.hpp:150) ==452== by 0x4198724: void boost::io::detail::distribute<char, std::char_traits<char>, std::allocator<char>, unsigned&>(boost::basic_format<char, std::char_traits<char>, std::allocator<char> >&, unsigned&) (feed_args.hpp:241) ==452== by 0x4198783: boost::basic_format<char, std::char_traits<char>, std::allocator<char> >& boost::io::detail::feed<char, std::char_traits<char>, std::allocator<char>, unsigned&>(boost::basic_format<char, std::char_traits<char>, std::allocator<char> >&, unsigned&) (feed_args.hpp:251) ==452== by 0x4198849: boost::basic_format<char, std::char_traits<char>, std::allocator<char> >& boost::basic_format<char, std::char_traits<char>, std::allocator<char> >::operator%<unsigned>(unsigned&) (format_class.hpp:68) ==452== by 0x41940EE: libreverse::data_container::Memory_Map::Memory_Map(std::string, unsigned) (Memory_Map.cpp:87) ==452== by 0x41D2D85: libreverse::io::File::read_Image() (File.cpp:119) ==452== by 0x41D30F1: libreverse::io::File::init() (File.cpp:151) ==452== by 0x8089A2B: libreverse::wpef_module::PE_File<32>::init() (PE_File_T.cpp:48) ==452== Address 0x30 is not stack'd, malloc'd or (recently) free'd ==452== I made a driver program for this line. The driver works fine. #include <boost/cstdint.hpp> #include <boost/format.hpp> #include <iostream> #include <fstream> int main (int, char**) { boost::uint32_t reserve_length = 0; std::ifstream input_ref ( "kernel32.dll", std::ios::binary | std::ios::in ); input_ref.seekg ( 0, std::ios::end ); reserve_length = input_ref.tellg(); std::cout << boost::format("Something done %d") % reserve_length << std::endl; } So I cannot provide you an easy example. I am sorry about this. I hope I am asking an intelligent question. Stephen

1 0

Re: [Boost-users] [serialization] linker errors using polymorphicarchives
by Robert Ramey 19 May '07

19 May '07

I just ran the test program on my machine with VC 7.1 and it seems to build and execute just fine. Also I not that the RC 1.34 test of this facility passes as well. So I would look more carefully at the library search setup, auto-linking, etc. Robert Ramey MOSS Sebastian wrote: > I am getting a similar problem using the test example - verbatim - > from > the doc page > http://www.boost.org/libs/serialization/doc/archive_reference.html#polym > orphic, even after explicitly declaring > > template void > boost::archive::text_oarchive_impl<boost::archive::text_oarchive>::save( > std::basic_string<unsigned short,struct std::char_traits<unsigned > short>,class std::allocator<unsigned short> > const &); > > Does anyone have any recommendations for this? > > Thanks in advance, > Sebastian > > ******************************* > This e-mail contains information for the intended recipient only. It > may contain proprietary material or confidential information. If you > are not the intended recipient you are not authorised to distribute, > copy or use this e-mail or any attachment to it. Murex cannot > guarantee that it is virus free and accepts no responsibility for any > loss or damage arising from its use. If you have received this > e-mail in error please notify immediately the sender and delete the > original email received, any attachments and all copies from your > system.

2 1

tokenizer
by ivan＠0x4849.net 19 May '07

19 May '07

Hi, I am doing very large loop where i need to tokenize a string in each iteration. At each iteration of the loop there will be a string contained in char*. It seems that in order to use the boost tokenizer, it is necessary to copy the string into a std::string rather than using the data directly from the char*. This is adding a copy for each iteration to the loop. Is there no way to use the tokenizer directly on a char* rather than std::string? Thank you, Ivan Novick http://www.0x4849.net

2 1

[Build 1.34.0 MinGW] I'm getting different build files for 1.34.0 than I did for 1.33.1
by Ken Klose 18 May '07

18 May '07

When I built boost 1.33.1 with GCC 3.4.5 on WinXP I got 274 files in the \boost\lib directory consisting of both DLLs and .lib files. When I built boost 1.34 (following the new getting started directions) I only got 154 files in \boost\lib none were DLL or LIB, they were all .a files. Interestingly when the 1.34.0 build starts I get "Unable to construct ./install-unversioned" messages that I don't get in the 1.33.1 build: ...found 1 target... C:\src\c++\boost_1_34_0>bjam --toolset=gcc --prefix=C:\Boost1.34.0 install Building Boost.Regex with the optional Unicode/ICU support disabled. Please refer to the Boost.Regex documentation for more information (don't panic: this is a strictly optional feature). warning: Unable to construct ./install-unversioned warning: Unable to construct ./install-unversioned warning: Unable to construct ./install-unversioned Thanks, Ken

2 4

[serialization] linker errors using polymorphic archives
by MOSS Sebastian 18 May '07

18 May '07

Hi, I'm trying to use the polymorphic interfaces so I can separate components in a serialization library, however I'm having problems resolving the following linker errors using vc71: boost error LNK2019: unresolved external symbol "public: void __thiscall boost::archive::text_iarchive_impl<class boost::archive::text_iarchive>::load(class std::basic_string<unsigned short,struct std::char_traits<unsigned short>,class std::allocator<unsigned short> > &)" (?load@?$text_iarchive_impl@Vtext_iarchive@archive@boost@@@archive@boost @@QAEXAAV?$basic_string@GU?$char_traits@G@std@@V?$allocator@G@2@@std@@@Z ) referenced in function "private: virtual void __thiscall boost::archive::detail::polymorphic_iarchive_impl<class boost::archive::text_iarchive_impl<class boost::archive::text_iarchive> >::load(class std::basic_string<unsigned short,struct std::char_traits<unsigned short>,class std::allocator<unsigned short> > &)" (?load@?$polymorphic_iarchive_impl@V?$text_iarchive_impl@Vtext_iarchive@ archive@boost@@@archive@boost@@@detail@archive@boost@@EAEXAAV?$basic_str ing@GU?$char_traits@G@std@@V?$allocator@G@2@@std@@@Z) and similar for the save interface. I am getting a similar problem using the test example - verbatim - from the doc page http://www.boost.org/libs/serialization/doc/archive_reference.html#polym orphic, even after explicitly declaring template void boost::archive::text_oarchive_impl<boost::archive::text_oarchive>::save( std::basic_string<unsigned short,struct std::char_traits<unsigned short>,class std::allocator<unsigned short> > const &); Does anyone have any recommendations for this? Thanks in advance, Sebastian ******************************* This e-mail contains information for the intended recipient only. It may contain proprietary material or confidential information. If you are not the intended recipient you are not authorised to distribute, copy or use this e-mail or any attachment to it. Murex cannot guarantee that it is virus free and accepts no responsibility for any loss or damage arising from its use. If you have received this e-mail in error please notify immediately the sender and delete the original email received, any attachments and all copies from your system.

1 0