February 2008 - Boost-users - lists.preview.boost.org

[utility] question about enable_if
by Christian Henning 15 Feb '08

15 Feb '08

Hi there, I'm having a problem with using enable_if. For the sake of simplicity I have created the following test code which compiles fine. #include <string> #include <boost/mpl/and.hpp> #include <boost/utility/enable_if.hpp> using namespace std; using namespace boost; struct reader {}; template< typename String > struct is_string : public mpl::false_ {}; template<> struct is_string<std::string> : public mpl::true_ {}; template< typename Device > struct is_device : public mpl::false_ {}; template<> struct is_device<reader> : public mpl::true_ {}; template< typename String> struct enable_if_helper { typedef typename enable_if< typename is_string< String >::type >::type type; }; template<typename Device > void foo( typename enable_if< typename is_device<Device>::type >::type* ptr = 0 ) {} template<typename String> void foo( typename enable_if< typename is_string<String>::type >::type* ptr = 0 ) { foo<reader>(); } int main(int argc, _TCHAR* argv[]) { foo<std::string>(); return 0; } If I changed the string foo() interface to use the enable_if_helper the code doesn't compile anymore. Why is that? I've changed the foo ( with the string template parameter ) to the following: template<typename String> void foo( typename enable_if_helper< String >::type* ptr = 0 ) { foo<reader>(); } Anyone can help me out here? I'm using Visual Studio 8. Thanks, Christian

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[xpressive] Pattern problems (newbie)
by ope 14 Feb '08

14 Feb '08

Hi, I'try to build a regex for an ibis file, the line I'm interested looks like: [IBIS Ver] 3.2 | Used for template variations" where '|' is an optional comment identifier with the (therefore optional) comments follows. I'm interested in the version self: "3.2" to create a parser using a factory. Using egrep '^\[IBIS Ver]' success. From docs I tested the dynamic regex $ perl -p -e '(\\w+) (\\w+)!' "Hello World" which fails (syntax error at -e line 1, near "+) ") The regex are perl syntax, isn't? What is the regex for my IBIS Ver identifier? Thanks, Olaf

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[iostreams] Question about correct opened file
by ope 14 Feb '08

14 Feb '08

Hi, I've the following code: namespace io = boost::iostreams; bool foo::open( const std::string& file ) { io::filtering_istream is; is.push( my_line_filter() ); is.push( io::file_source( file ) ); // ??? how to check success do { std::string line; std::getline(is, line); std::cout << line << std::endl; } while (!is.eof()); return true; } Well, how can I check that the file is opened correct/the stream is valid? is_open() and good() seems not supported? Or I'm wrong? Giving a wrong name does nothings. Thanks, Olaf

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Linker Errors
by Srinivas Chamarthi 14 Feb '08

14 Feb '08

Hi All, - I have built STL5.1.4 with VC8. - boost against stlport with the following command -> make - fvc8-stlport.mak *It created all the necessary libs and dlls. * I have defined the following in my application. *#define __STL_DEBUG #define BOOST_REGEX_DYN_LINK * But I am still getting the following linker errors. Any one can help me with these errors ? *Appreciate your help in advance* Error 3 error LNK2019: unresolved external symbol "__declspec(dllimport) public: __thiscall boost::match_results<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> > >::~match_results<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> > >(void)" (__imp_??1?$match_results@ PBDV?$allocator@U?$sub_match@PBD@boost@@@stlp_std@@@boost@@QAE@XZ) referenced in function "public: static bool __cdecl ExprEvaluator::doesStringMatchRegExpr(char const *,class boost::basic_regex<char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >)" (?doesStringMatchRegExpr@ExprEvaluator@@ SA_NPBDV?$basic_regex@DU?$regex_traits@DV?$w32_regex_traits@D@boost@@@boost@@@boost@@@Z) ExprEvaluator.obj Error 4 error LNK2019: unresolved external symbol "__declspec(dllimport) public: __thiscall boost::match_results<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> > >::match_results<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> > >(class stlp_std::allocator<struct boost::sub_match<char const *> > const &)" (__imp_??0?$match_results@ PBDV?$allocator@U?$sub_match@PBD@boost@@@stlp_std@@@boost@@QAE@ABV ?$allocator@U?$sub_match@PBD@boost@@@stlp_std@@@Z) referenced in function "public: static bool __cdecl ExprEvaluator::doesStringMatchRegExpr(char const *,class boost::basic_regex<char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >)" (?doesStringMatchRegExpr@ExprEvaluator@@ SA_NPBDV?$basic_regex@DU?$regex_traits@DV?$w32_regex_traits@D@boost@@@boost@@@boost@@@Z) ExprEvaluator.obj Error 5 error LNK2019: unresolved external symbol "__declspec(dllimport) public: __thiscall boost::re_detail::perl_matcher<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> >,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >::~perl_matcher<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> >,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >(void)" (__imp_??1?$perl_matcher@PBDV?$allocator@U?$sub_match@PBD@boost@@@stlp_std@@ U?$regex_traits@DV?$w32_regex_traits@D@boost@@@boost@@@re_detail@boost@@ QAE@XZ) referenced in function "bool __cdecl boost::regex_match<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> >,char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >(char const *,char const *,class boost::match_results<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> > > &,class boost::basic_regex<char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > > const &,enum boost::regex_constants::_match_flags)" (??$regex_match@PBDV?$allocator@U ?$sub_match@PBD@boost@@@stlp_std@@DU?$regex_traits@DV?$w32_regex_traits@ D@boost@@@boost@@@boost@@YA_NPBD0AAV?$match_results@PBDV?$allocator@ U?$sub_match@PBD@boost@@@stlp_std@@@0@ABV?$basic_regex@DU?$regex_traits@DV ?$w32_regex_traits@D@boost@@@boost@@@0@W4_match_flags@regex_constants@0@@Z) ExprEvaluator.obj Error 6 error LNK2019: unresolved external symbol "__declspec(dllimport) public: bool __thiscall boost::re_detail::perl_matcher<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> >,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >::match(void)" (__imp_?match@?$perl_matcher@PBDV?$allocator@U?$sub_match@PBD@boost @@@stlp_std@@U?$regex_traits@DV?$w32_regex_traits@D@boost@@@boost@@@ re_detail@boost@@QAE_NXZ) referenced in function "bool __cdecl boost::regex_match<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> >,char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >(char const *,char const *,class boost::match_results<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> > > &,class boost::basic_regex<char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > > const &,enum boost::regex_constants::_match_flags)" (??$regex_match@ PBDV?$allocator@U?$sub_match@PBD@boost@@@stlp_std@@DU?$regex_traits@DV ?$w32_regex_traits@D@boost@@@boost@@@boost@@YA_NPBD0AAV?$match_results@PBDV ?$allocator@U?$sub_match@PBD@boost@@@stlp_std@@@0@ABV?$basic_regex@ DU?$regex_traits@DV?$w32_regex_traits@D@boost@@@boost@@@0@W4_match_flags@ regex_constants@0@@Z) ExprEvaluator.obj Error 7 error LNK2019: unresolved external symbol "__declspec(dllimport) public: __thiscall boost::re_detail::perl_matcher<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> >,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >::perl_matcher<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> >,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >(char const *,char const *,class boost::match_results<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> > > &,class boost::basic_regex<char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > > const &,enum boost::regex_constants::_match_flags,char const *)" (__imp_??0?$perl_matcher@PBDV?$allocator@U?$sub_match@PBD@boost@@@stlp_std@@ U?$regex_traits@DV?$w32_regex_traits@D@boost@@@boost@@@re_detail@boost@@ QAE@PBD0AAV?$match_results@PBDV?$allocator@U?$sub_match@PBD@boost @@@stlp_std@@@2@ABV?$basic_regex@DU?$regex_traits@DV?$w32_regex_traits@ D@boost@@@boost@@@2@W4_match_flags@regex_constants@2@0@Z) referenced in function "bool __cdecl boost::regex_match<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> >,char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >(char const *,char const *,class boost::match_results<char const *,class stlp_std::allocator<struct boost::sub_match<char const *> > > &,class boost::basic_regex<char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > > const &,enum boost::regex_constants::_match_flags)" (??$regex_match@PBDV?$allocator@U ?$sub_match@PBD@boost@@@stlp_std@@DU?$regex_traits@DV?$w32_regex_traits@ D@boost@@@boost@@@boost@@YA_NPBD0AAV?$match_results@PBDV?$allocator@ U?$sub_match@PBD@boost@@@stlp_std@@@0@ABV?$basic_regex@DU?$regex_traits@DV ?$w32_regex_traits@D@boost@@@boost@@@0@W4_match_flags@regex_constants@0@@Z) ExprEvaluator.obj thanks & regards Srinivas Chamarthi

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DebuggerVisualizers update
by Filip Konvička 14 Feb '08

14 Feb '08

Hi Boost, I've just updated the Debugger Visualizers wiki at http://svn.boost.org/trac/boost/wiki/DebuggerVisualizers The main change is that the visualizer files are now all available at https://svn.boost.org/svn/boost/sandbox/boost_docs/subprojects/DebuggerVisu… and, thanks to the effort and interest of Jon Fogh, there is a new visualizer for boost::interprocess::offset_ptr. Enjoy, Filip

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Serialization hash_map
by christophe loustaunau 14 Feb '08

14 Feb '08

Hello, Recently I have used Boost for serialization. Unfortunatly it doesn't work with hash_map. I work with Visual 8, and Visual 8 used the dinkumware version of std lib. In order to make things working I have modified three files of boost : in the folder config/stdlib : dinkumware.hpp : BOOST_HAS_HASH is not defined.(why ?). in the folder serialization : hash_collections_load_imp.hpp : In this file I have made these changes : template<class Archive, class Container, class InputFunction> inline void load_hash_collection(Archive & ar, Container &s) { s.clear(); // retrieve number of elements unsigned int count; unsigned int item_version(0); // unsigned int bucket_count;; ar >> BOOST_SERIALIZATION_NVP(count); // if(3 < ar.get_library_version()){ // ar >> BOOST_SERIALIZATION_NVP(bucket_count); // ar >> BOOST_SERIALIZATION_NVP(item_version); // } // #if ! defined(__MWERKS__) // s.resize(bucket_count); // #endif InputFunction ifunc; while(count-- > 0){ ifunc(ar, s, item_version); } } } // namespace stl } // namespace serialization } // namespace boost hash_collections_save_imp.hpp : In this file I have made these changes : template<class Archive, class Container> inline void save_hash_collection(Archive & ar, const Container &s) { // record number of elements unsigned int count = s.size(); ar << BOOST_SERIALIZATION_NVP(count); // make sure the target type is registered so we can retrieve // the version when we load // if(3 < ar.get_library_version()){ // const unsigned int bucket_count = s.bucket_count(); // ar << BOOST_SERIALIZATION_NVP(bucket_count); // const unsigned int item_version = version<BOOST_DEDUCED_TYPENAME Container::value_type>::value; // ar << BOOST_SERIALIZATION_NVP(item_version); // } BOOST_DEDUCED_TYPENAME Container::const_iterator it = s.begin(); while(count-- > 0){ // note borland emits a no-op without the explicit namespace boost::serialization::save_construct_data_adl( ar, &(*it), boost::serialization::version< BOOST_DEDUCED_TYPENAME Container::value_type >::value ); ar << boost::serialization::make_nvp("item", *it++); } } } // namespace stl } // namespace serialization } // namespace boost With this changes Serialization of hash_map works well. Maybe you could make a : #if (!defined dinkumware ) ..... # endif In theses two files in order to make the serialization of hash_map with dinkumware working. Thanks for your time and your so good library ! -- Christophe Loustaunau.

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tuple<...involves template par...>
by e r 14 Feb '08

14 Feb '08

Hi, I have the following: template<typename T> class A: public std::unary_function<const boost::tuple<double,const T&>&, void>{ public: typedef typename std::unary_function<const boost::tuple<double,const T&>&, void> parent_type; typedef typename parent_type::argument_type argument_type; void operator()(argument_type t)const{ t.get<0>(); //error: expected primary-expression before ')' token t.get<1>(); //error: expected primary-expression before ')' token }; }; Similar code without the template (i.e. fix say T = double) works fine. Anybody, pls help. Thanks.

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[lambda] Compilation problem because of EXCEPTION
by Knut Hunstad 13 Feb '08

13 Feb '08

Hi! I haven't used boost much yet, but have been looking into lambda expressions. I am working within a huge system, where one of the include files has a macro definition for EXCEPTION. Which is also used as an enum value in boost/lambda/detail/arity_code.hpp (within namespace boost::lambda): enum { NONE = 0x00, // Notice we are using bits as flags here. FIRST = 0x01, SECOND = 0x02, THIRD = 0x04, EXCEPTION = 0x08, RETHROW = 0x10}; Using common names such as this in a general library seems a bit risky to me. Any header before "boost/lambda.hpp" which defines macros for any of these enum values, will cause trouble. I don't have insight enough in boost to suggest the correct solution (or to conclude that I have to fix the problem in my own code and let boost::lambda remain unchanged :-). For me right now the fix was simply replacing the (4) occurences of this EXCEPTION with LAMBDAEXCEPTION in the boost files. Where do I go to put this up as a fix-suggestion? I would like to avoid having to remember this replace every time I upgrade boost... Best regards, Knut Hunstad Vianova Systems AS Norway

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[Interprocess] gcc 3.2 support?
by Matt Wharton 13 Feb '08

13 Feb '08

Greetings, So, I appear to have hit a stumbling block with GCC 3.2 and Boost.Interprocess (the latest from the release branch which I _believe_ to be the latest 1.35). Specifically, when I try to build the following code, I get numerous compilation errors (they appear to be template related). ---------------------- #include <boost/interprocess/managed_shared_memory.hpp> int main() { return 0; } ------------------------- Is there any way to get this work under my older GCC version or am I out of luck? Thanks in advance! -Matt

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Re: [Boost-users] XML Serialization and the Generation of a W3C Schema
by Joseph Fradley 13 Feb '08

13 Feb '08

Robert, Fair enough, I'll see if I can make something useful in the amount of time I have. Joe > I don't. I guess its up to you. > > Robert Ramey > > Joseph Fradley wrote: > > Hello, > > > > I've seen a few postings on how a XSD generating archiver would be > > written and a posting for a google code project on it. But I can't > > seem to find any implementations. > > > > Does anybody know of any implementations? > > > > Joe >

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