July 2006 - Boost-users - lists.boost.org

TR: [Serialisation] error with xml_iarchive
by Bruno Poinas 31 Jul '06

31 Jul '06

Hello, I just recently began using the boost library, I want to write and read string to serialized objects with the function 'xml_oarchive' and 'xml_iarchive'. When I execute this code (with visual c++.net v. 7.1) : std::ofstream ofs("C:\\Save.xml"); const wchar_t * ptr; ptr=m_strEdit.GetBuffer(); assert(ofs.good()); boost::archive::xml_oarchive oa(ofs); oa.save(ptr); wchar_t str[512]; std::ifstream ifs("C:\\Save.xml"); boost::archive::xml_iarchive ia(ifs,0); ia.load(str); ifs.close(); the programm failed : Thanks and regards, Bruno POINAS ActiCM S.A. 122, rue du Rocher de Lorzier - Centr'Alp - 38430 - MOIRANS

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[multi_index] illegal indirection compile error
by Themistoklis Bourdenas 31 Jul '06

31 Jul '06

Could you help me understand what I'm doing wrong in the code below? I'm trying to setup a multi_index structure of class B. class A { const std::string& ID(void) const; ... }; class B : public A { ... }; typedef boost::multi_index::multi_index_container< B*, boost::multi_index::indexed_by< boost::multi_index::ordered_unique< boost::multi_index::const_mem_fun<A, const std::string&, &A::ID> > > > BSet; However when I compile VS2005 returns me an "illegal indirection" compile error. Any thoughts? Thanks

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Implementing copy_if using boost::lambda
by Minkoo Seo 31 Jul '06

31 Jul '06

Hi list. I'm trying to implment copy_if using boost::lambda: #include <iostream> #include <string> #include <vector> #include <algorithm> #include <iterator> #include <map> #include <boost/lambda/lambda.hpp> #include <boost/lambda/if.hpp> #include <boost/format.hpp> #include <boost/lambda/bind.hpp> #include <boost/lambda/algorithm.hpp> using namespace std; using namespace boost::lambda; int main() { vector<int> vi; vi.push_back(1); vi.push_back(2); vi.push_back(3); vi.push_back(4); vi.push_back(5); vector<int> vi2; for_each(vi.begin(), vi.end(), if_then(_1 == 1, vi2.push_back(_1))); return EXIT_SUCCESS; } This fails with the errors: lambda_test.cpp: In function 'int main()': lambda_test.cpp:30: error: no matching function for call to 'std::vector<int, std::allocator<int> >::push_back(const boost::lambda::lambda_functor<boost::lambda::placeholder<1> >&)' /usr/lib/gcc/x86_64-redhat-linux/4.0.2/../../../../include/c++ ]/4.0.2/bits/stl_vector.h:602: note: candidates are: void std::vector<_Tp, _Alloc>::push_back(const _Tp&) [with _Tp = int, _Alloc = std::allocator<int>] Does anybody know how to push _1 into vi2? I've tried bind( ), but no luck. Sincerely, Minkoo Seo

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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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