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boost::bind question
by Surya Kiran Gullapalli 31 Jul '06

31 Jul '06

Hi, I've a std::map with the following structure. std::map < int, tuple<std::string, std::string> > mapTuple ; typedef map < int, tuple<string, string> > mapTuple ; Now i've say 10 elements in this container. Now i'd like to iterate thru this container and find a specific element which matches a certain criteria. Right now I'm doing this. MapIntTuple::iterator iter ; for (iter = mymap.begin(); iter != mymap.end(); ++iter) { if (iter->second.get<0>() == current_field) break ; } I'd like to iterate thru the container and find the element whose first string in the tuple matches with my search string. How can i do this using boost::lamdba::bind and std::find_if. May be that will help me in understanding boost::bind better. iter = find_if (mymap.begin(), mymap.end(), ???) ; Thanks in advance, Surya

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g++ warning: comparing floating point with == or != is unsafe
by cybernet＠interia.pl 31 Jul '06

31 Jul '06

In: /usr/include/boost/test/floating_point_comparison.hpp inside: template<typename FPT> inline FPT safe_fpt_division( FPT f1, FPT f2 ){ the warning is cause by the code: // Avoid underflow. if( f1 == static_cast<FPT>(0) || f2 > static_cast<FPT>(1) && f1 < f2 * (std::numeric_limits<FPT>::min)() ) return static_cast<FPT>(0); Could someone modify the code to allow it to compile without warnings on g++? Latest CVS version still has this problem. I'm too dumb to think of a reasonable patch to submit - sorry. ---------------------------------------------------------------------- PS. Fajny portal... >>> http://link.interia.pl/f196a

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FW: BOOST_CHECK vs. BOST_CHECK_EQUAL, checking equality of wchar_ts
by Tan Zhi 31 Jul '06

31 Jul '06

According to the document, BOOST_CHECK is the same as BOST_CHECK_EQUAL. However,I found an exception. Which is listed below, where m_mmf.SetLngGetString(1033, 1) returns a const wchar_t* type. Interestingly, the first two tests fail, while the last two pass. BOOST_CHECK(L"A" == m_mmf.SetLngGetString(1033, 1)); BOOST_CHECK(m_mmf.SetLngGetString(1033, 1) == L"A" ); BOOST_CHECK_EQUAL(L"A", m_mmf.SetLngGetString(1033, 1)); BOOST_CHECK_EQUAL(m_mmf.SetLngGetString(1033, 1), L"A"); Can any one please help to explain it? Thanks

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Problems Building Boost 1.33.1 on Ubuntu 5.10 x86 From Scratch
by kfjethro 30 Jul '06

30 Jul '06

I know that there are probably packages available for this platform but for several reasons I need to build Boost 1.33.1 from scratch. I have no problems with compiliing from scratch on Ubuntu 6.06. After unpacking the source files and placing the precompiled bjam executable in the boost source directory, I run the following: cd ./boost_1_33_1 ./bjam -sTOOLS=gcc –-prefix=/usr/local/boost-1.33.1 install My /usr/local/boost-1.33.1 is owned by me and writeable. Any suggestions ? Thanks. The truncated bjam output is : Building Boost.Regex with the optional Unicode/ICU support disabled. Please refer to the Boost.Regex documentation for more information (and if you don't know what ICU is then you probably don't need it). --------------------------------------------------------------------- *** If you don't need Boost.Python, you can ignore this section *** *** pass --without-python to suppress this message in the future *** skipping Boost.Python library build due to missing or incorrect configuration couldn't find Python.h in "/usr/include/python2.4" You can configure the location of your python installation by setting: PYTHON_VERSION - The 2-part python Major.Minor version number (e.g. "2.2", NOT "2.2.1") - currently "2.4" PYTHON_ROOT - currently "/usr" The following are automatically configured from PYTHON_ROOT if not otherwise set: PYTHON_LIB_PATH - path to Python library object; currently "/usr/lib/python2.4/config" PYTHON_INCLUDES - path to Python #include directories; currently "/usr/include/python2.4" --------------------------------------------------------------------- Jamfile:278: in load-jamfiles *** argument error * rule stage ( name : sources + : requirements * : local-build * ) * called with: ( : /home/lawrence/boost_1_33_1/boost/compatibility/cpp_c_headers/cwchar /home/lawrence/boost_1_33_1/boost/compatibility/cpp_c_headers/csignal /home/lawrence/boost_1_33_1/boost/compatibility/cpp_c_headers/climits /home/lawrence/boost_1_33_1/boost/compatibility/cpp_c_headers/cfloat /home/lawrence/boost_1_33_1/b <<<< middle truncated >>>>>> r_traits.hpp /home/lawrence/boost_1_33_1/boost/pending/bucket_sorter.hpp /home/lawrence/boost_1_33_1/boost/pending/fibonacci_heap.hpp /home/lawrence/boost_1_33_1/boost/pending/iterator_tests.hpp /home/lawrence/boost_1_33_1/boost/pending/detail/int_iterator.hpp /home/lawrence/boost_1_33_1/boost/pending/detail/property.hpp /home/lawrence/boost_1_33_1/boost/pending/detail/disjoint_sets.hpp : <locate>/usr/local <tree-subdirs>/home/lawrence/boost_1_33_1 <target>install : ) * missing argument name /home/lawrence/boost_1_33_1/tools/build/v1/boost-base.jam:2330:see definition of rule 'stage' being called /home/lawrence/boost_1_33_1/tools/build/v1/bootstrap.jam:21: in boost-build /home/lawrence/boost_1_33_1/boost-build.jam:16: in module scope

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basic_string literals
by Johan Råde 30 Jul '06

30 Jul '06

Does Boost offer any facility for declaring basic_string literals in templates, i.e. something like basic_string<CharType> s = BOOST_STRING("foo"); Thank you, Johan Råde

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Re: [Boost-users] g++ warning: comparing floating point with == or!= is unsafe
by Nat Goodspeed 30 Jul '06

30 Jul '06

> -----Original Message----- > From: boost-users-bounces(a)lists.boost.org [mailto:boost-users- > bounces(a)lists.boost.org] On Behalf Of David Abrahams > Sent: Saturday, July 29, 2006 5:15 PM > To: boost-users(a)lists.boost.org > Subject: Re: [Boost-users] g++ warning: comparing floating point with == > or!= is unsafe > > > the warning is cause by the code: > > > > // Avoid underflow. > > if( f1 == static_cast<FPT>(0) || > > f2 > static_cast<FPT>(1) && f1 < f2 * > > (std::numeric_limits<FPT>::min)() ) > > return static_cast<FPT>(0); > > > > Could someone modify the code to allow it to compile without warnings on > > g++? > > Try replacing > > f1 == static_cast<FPT>(0) > > with > > f1 [Nat] Maybe (! f1) instead?

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boost::bind question / bug(?)
by Michael Nicolella 30 Jul '06

30 Jul '06

Having trouble compiling this code. Only tested in VC8: Removing 'const' from only the static class function seems to allow it to compile. Below is the error messages... #include <boost/bind.hpp> #include <boost/function.hpp> struct A { static void foo( const int ) { } }; void bar( const int ) { } int main() { boost::bind( &A::foo, _1 ) ; boost::bind( &bar, _1 ) ; } ------------- 1>------ Rebuild All started: Project: test_vc8, Configuration: Debug Win32 ------ 1>Deleting intermediate and output files for project 'test_vc8', configuration 'Debug|Win32' 1>Compiling... 1>main6.cpp 1>c:\projects\test_vc8\test_vc8\main6.cpp(17) : error C2665: 'boost::bind' : none of the 2 overloads could convert all the argument types 1> c:\projects\boost\boost\bind.hpp(1400): could be 'boost::_bi::bind_t<R,F,L> boost::bind<void(*)(int),boost::arg<I>>(F,A1)' 1> with 1> [ 1> R=boost::_bi::unspecified, 1> F=void (*)(int), 1> L=boost::_bi::list1<boost::arg<1>>, 1> I=1, 1> A1=boost::arg<1> 1> ] 1> c:\projects\boost\boost\bind\bind_cc.hpp(26): or 'boost::_bi::bind_t<R,F,L> boost::bind<void,int,boost::arg<I>>(R (*)(B1),A1)' 1> with 1> [ 1> R=void, 1> F=void (*)(int), 1> L=boost::_bi::list1<boost::arg<1>>, 1> I=1, 1> B1=int, 1> A1=boost::arg<1> 1> ] 1> while trying to match the argument list '(void (*)(const int), boost::arg<I>)' 1> with 1> [ 1> I=1 1> ] 1>Build log was saved at "file://c:\projects\test_vc8\test_vc8\Debug\BuildLog.htm" 1>test_vc8 - 1 error(s), 0 warning(s) ========== Rebuild All: 0 succeeded, 1 failed, 0 skipped ==========

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seeking a better way of regex replacing!
by llwaeva＠21cn.com 30 Jul '06

30 Jul '06

Hi there, boost:regex is powerful in string replacing. I am working with a complicate case which need a faster method in replacing substring. Here is my problem. I have a big string contains some pattern %K{xxx}, where xxx is a filename which may vary from place to place. e.g. BIG_STRING = ... ... %K{abc.txt} ... ... ... ... %K{foo.ini} ... ... OK, what complicated is that: I must retrieve the filename from %K{xxx}, load the content of the file and then replace %K{xxx} with the content. I search the code with a loop string::const_iterator start, end; string filename, content; boost::regex re("%K\\{(.*)\\}"); boost::match_results<std::string::const_iterator> what; boost::match_flag_type flags = boost::match_default; start = BIG_STRING.begin(); end = BIG_STRING.end(); while ( regex_search(start, end, what, re, flags) ) { if (what[1].first!=what[1].second) { filename = string(what[1].first, what[1].second); } content = LoadFile(filename); // transform the const_iterator to iterator string::iterator sbegin(BIG_STRING.begin()), send(BIG_STRING.begin()); std::advance(sbegin, distance<string::const_iterator>(sbegin, what[0].first)); std::advance(send, distance<string::const_iterator>(send, what[0].second)); // replace the content BIG_STRING.replace( sbegin, send, content ); // reset the current position of the source string to search the next pattern start = what[1].second; // I copy the code from the document of boost, don't know what the following code for flags |= boost::match_prev_avail; flags |= boost::match_not_bob; } The second approach is to retrieve the filename and load the content seperately, build the substitute format and replace all the patterns with replace_all_regex, e.g. string& escape_format( string& input ) { replace_all( input, "$", "$$" ); replace_all( input, "\\", "\\\\" ); replace_all( input, ":", "\\:" ); replace_all( input, "?", "\\?" ); replace_all( input, "(", "\$" ); replace_all( input, ")", "\$" ); return input; } stringstream reformat; string regex_text; int n=0; while ( regex_search(start, end, what, re, flags) ) { if (what[1].first!=what[1].second) { filename = string(what[1].first, what[1].second); } content = LoadFile(filename); regex_text += string(what[0].first, what[0].second); reformat << "(?" << ++n << " " << escape_format( content ) << ")"; // reset the current position of the source string to search the next pattern start = what[1].second; // I copy the code from the document of boost, don't know what the following code for flags |= boost::match_prev_avail; flags |= boost::match_not_bob; } // replace the whole string at last replace_all_regex( BIG_STRING, boost::regex(regex_text), reformat.str(), format_all ); But this approach cause exception!!! Any better idea for my problem? Thanks in advance.

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BOOST_CHECK problem!
by 袁晓辉 30 Jul '06

30 Jul '06

The doc says "It(BOOST_CHECK) also increments an error count<http://www.boost.org/libs/test/doc/components/minimal_testing/index.html>", but it seems not: #include <boost/test/included/unit_test_framework.hpp> using boost::unit_test::test_suite; void test1() { BOOST_CHECK(false); } test_suite* init_unit_test_suite( int, char* [] ) { test_suite* test= BOOST_TEST_SUITE( "Unit test ); test->add( BOOST_TEST_CASE( &test1), 1); return test; } Output: ----------------------------------------------------- Running 1 test case... xxx.cpp(171): error in "test1": check false failed *** No errors detected ----------------------------------------------------- ps. I am using boost-1_33_1.

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replace_all_regex help
by llwaeva＠21cn.com 30 Jul '06

30 Jul '06

Hi there, I wrote a piece of code to handle MIME header based on boost. The program subsitite the MIME header (from, to, subject, etc.) into a template with specific macro. Because the macro may occur everywhere in the template once or more, so I apply replace_all_regex. First of all, I need to transform the substitute string to escape special characters // input is a substitute string that will replace the macro string& escape_format( string& input ) { replace_all( input, "$", "$$" ); replace_all( input, "\\", "\\\\" ); replace_all( input, ":", "\\:" ); replace_all( input, "?", "\\?" ); replace_all( input, "(", "\$" ); replace_all( input, ")", "\$" ); return input; } There are some macros definied, some of them are listed below %s represents the subject (e.g. Re: hi philip!) %S represents the subject without prefix "Re:" (e.g hi philip!) %f represents the "form" (e.g. tom(a)hotmail.com) %t represents the "to" (e.g. philip(a)hotmail.com) ... With regex, I can replace all the macros with the help of format, something like replace_all_regex( source, boost::regex("(%f)|(%t)|(%s)|(%S)"), "(?1 xxx)(?2 yyy)(?3 aaa)(?4 bbb)", format_all ); In order to get the subject without prefix "Re:", I use erase_regex as follow string& deRe(string& input) { boost::regex regexp("^[[:space:]]*Re:[[:space:]]*"); erase_regex( input, regexp ); return input; } So simple!!! However, the order and number of macro will be changed sometimes. So I need a better way to build regex and format. I've got a function to do that // rformat is a stringstream for building a format // text is a substitute string // re_text is a string for building a regular expression // re is a string or regular expression, i.e. the macro // format_num is an global integer to hold the current number of format items (initialize to zero) void format_text(stringstream& rformat, string& text, string& re_text, const string& re) { format_num++; rformat << "(?" << format_num << " " << escape_format(text) << ")"; if (format_num>1) re_text += "|"; re_text += "(" + re + ")"; } Now, it's ready to build the regular expression and subsitiude formation dynamically. Here is an example, string regex_text; stringstream reformat; string source; // source is a string containing text and macros // spHeader is char* which is obtained from MIME parser. // if (spHeader) { format_text( reformat, string(spHeader), regex_text, "%s" ); // for %s format_text( reformat, deRe(string(spHeader)), regex_text, "%S" ); // for %S // Suppose spHeader is "Re: hi philp!", then // regex_text = "(%s)|(%S)" // reformat.str() = "(?1 Re: hi philip!)(?2 hi philip!)" replace_all_regex( source, boost::regex(regex_text), reformat.str(), format_all ); } Everything is fine except that there are some meaningless characters at the end of the output string (still source). By checking the code carefully, I found that the problem maybe caused by the format_text for %S. Hiding the second format_text solve the problem. However, just hiding the first format_text also solve the problem. It is confusing me! Someone please give me a direction. Thanks.

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