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enable_if question
by Hurd, Matthew 08 Jun '04

08 Jun '04

I'm just trying to play with enable_if and learn something. I just mean to replace this template method's code: template< bool > void exchange_code( boost::call_traits<std::string>::param_type new_exchange_code ) { if ( boost::is_arithmetic<std::string>::value ) { lock lk(guard_ ); exchange_code<false>( new_exchange_code); } else { exchange_code<false>( new_exchange_code); } } With this: template< bool > typename boost::enable_if_c< boost::is_arithmetic<std::string>::value, void >::type exchange_code( boost::call_traits<std::string>::param_type new_exchange_code ) { lock lk(guard_ ); exchange_code<false>( new_exchange_code); } template< bool > typename boost::disable_if_c< boost::is_arithmetic<std::string>::value , void >::type exchange_code( boost::call_traits<std::string>::param_type new_exchange_code ) { exchange_code<false>( new_exchange_code); } Forget the relevance of the is_arithmetic bit, I use my own needs_lock thingo. For a start: The compiler correctly identifies that ::type is not a member, but SFINAE does not seem to kick in if I'm reading it correctly. ____________________ c:\source\matt\trading_engine\controller\instrument.hpp(66) : error C2039: 'type' : is not a member of 'boost::enable_if_c<B,T>' with [ B=false, T=void ] c:\source\matt\trading_engine\controller\instrument.hpp(143) : see reference to class template instantiation 'te::instrument<S>' being compiled ____________________ template< bool > typename boost::disable_if_c< boost::is_arithmetic<std::string>::value , void >::type exchange_code( boost::call_traits<std::string>::param_type new_exchange_code ) { exchange_code<false>( new_exchange_code); } Is fine... Flipping the conditions round by changing to is_arithmetic< int > flips the failures around. Same issue with the extra parameter approach: template< bool > void exchange_code( boost::call_traits<std::string>::param_type new_exchange_code, typename boost::enable_if_c< boost::is_arithmetic<int>::value, void >::type* dummy = 0 ) { lock lk(guard_ ); exchange_code<false>( new_exchange_code); } template< bool > void exchange_code( boost::call_traits<std::string>::param_type new_exchange_code, typename boost::disable_if_c< boost::is_arithmetic<int>::value , void >::type* dummy = 0 ) { exchange_code<false>( new_exchange_code); } Is SFINAE meant to work in this way with member templates with enable_if, vc7.1 and boost 1.31? Something simple is probably escaping me... Any thoughts? Regards, Matt Hurd. _______________ Matt Hurd +61.2.8226.5029 hurdm(a)sig.com Susquehanna _______________ IMPORTANT: The information contained in this email and/or its attachments is confidential. If you are not the intended recipient, please notify the sender immediately by reply and immediately delete this message and all its attachments. Any review, use, reproduction, disclosure or dissemination of this message or any attachment by an unintended recipient is strictly prohibited. Neither this message nor any attachment is intended as or should be construed as an offer, solicitation or recommendation to buy or sell any security or other financial instrument. Neither the sender, his or her employer nor any of their respective affiliates makes any warranties as to the completeness or accuracy of any of the information contained herein or that this message or any of its attachments is free of viruses.

2 1

Looking for more advanced type_traits-like functionality
by Agoston Bejo 08 Jun '04

08 Jun '04

Hi, I have took a look at some parts of the boost library, but I couldn't find what I want, and that is something like this: How can I determine if a type T has such and such member? It would look like something like this: has_member<T, paint>::result (true if T::paint() exists) has_member<T, m_size>::result (true if T::m_size exists) The closest to this I could find is boost::type_traits but that does not provide this functionality. Thx, Gus

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boost::bind and boost::function fail at run-time in managed c++
by Russell Hind 08 Jun '04

08 Jun '04

Compiling the following code with /CLR on, results in an empty function exception at run-time. If you un-comment the #pragma unmanaged to get native compilation, it runs fine. Thanks Russell #include "stdafx.h" #using <mscorlib.dll> //#pragma unmanaged #include <boost/bind.hpp> #include <boost/function.hpp> class Test_c { public: void test(void) { } }; int main() { Test_c Test; boost::function<void (void)> f(boost::bind(&Test_c::test, &Test)); f(); return 0; }

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remove_const, is_const with arrays
by Richard Crossley 08 Jun '04

08 Jun '04

I'm seeing, what appears to me anyhow, rather strange behaviour with is_const and remove_const etc when used with arrays. With VC71 and a recent cvs I see... is_same<remove_const<const int[1]>::type,int[1]>::value; // true is_const<const int[1]>::value; // false ?? is_same<remove_const<const int[1][1]>::type,int[1][1]>::value; // false ?? is_same<add_const<int[1][1]>::type,const int[1][1]>::value; // true is_const<const int[1][1]>::value; // false ?? is_volatile<volatile int[1]>::value; // false ?? is_same<remove_volatile<volatile int[1][1]>::type,int[1][1]>::value; // false ?? is_same<add_volatile<int[1][1]>::type,volatile int[1][1]>::value; // true Using Comeau 4.3.3; is_same<remove_const<const int[1]>::type,int[1]>::value; // true is_const<const int[1]>::value; // true is_same<remove_const<const int[1][1]>::type,int[1][1]>::value; // false ?? is_same<add_const<int[1][1]>::type,const int[1][1]>::value; // true is_const<const int[1][1]>::value; // true is_volatile<volatile int[1]>::value; // true is_same<remove_volatile<volatile int[1][1]>::type,int[1][1]>::value; // false ?? is_same<add_volatile<int[1][1]>::type,volatile int[1][1]>::value; // true Regards, Richard.

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RE: [Boost-users] Looking for more advanced type_traits-likefunctionality
by Ben Hutchings 07 Jun '04

07 Jun '04

Agoston Bejo <gusz1(a)freemail.hu>: > Hi, > I have took a look at some parts of the boost library, but I couldn't > find what I want, and that is something like this: How can I determine > if a type T has such and such member? It would look like something > like this: > > has_member<T, paint>::result (true if T::paint() exists) > has_member<T, m_size>::result (true if T::m_size exists) > > The closest to this I could find is boost::type_traits but that does > not provide this functionality. Unfortunately that is impossible because templates can only manipulate constants, types and templates, not names. There is a technique that can be used to detect the definition of most operators, but it requires a separate template for each operator and it depends on being able to overload the operators through non-member functions. There may be a way to detect member functions but it cannot be done generically.

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Re: Re: boost regex support for 64-bit
by Yaron Hirsch 07 Jun '04

07 Jun '04

> The errors that we got: > > 1. The Workshop 6 errors (SunOS): > > CC -c -O2 -I../../../ -o sunpro/libboost_regex/c_regex_traits.o > ../src/c_regex_traits.cpp > "../../..//boost/regex/v4/match_flags.hpp", line 91: Error: Cannot > assign int to boost::regex_constants::_match_flags. > "../../..//boost/regex/v4/match_flags.hpp", line 93: Error: Cannot > assign int to boost::regex_constants::_match_flags. > "../../..//boost/regex/v4/match_flags.hpp", line 95: Error: Cannot > assign int to boost::regex_constants::_match_flags. > 3 Error(s) detected. > > These are just a few. The rest of the errors occured for the same > reasons in various files. (If you want those too - > let me know). > > 2. The aCC errors are (HP-IX): > aCC -o generic/boost_regex/cpp_regex_traits.o -c -Aa -AA +O2 > -I../../../ -O ../src/cpp_regex_traits.cpp > Error 742: "../src/cpp_regex_traits.cpp", line 382 # Source type > const char *& and target type char * in a const_cast can only differ in > their qualifiers > pmd->sbuf.pubsetbuf(const_cast<char*>(first), > static_cast<std::streamsize>(last-first)); > > I mistakingly wrote dynamic_cast in the original post, but I meant > const_cast. Sorry for the confusion. > > Please notice that we had to add manually some flags to generic.mak > (which is the makefile we used to build it > on HP-IX). I'm aware of some example you gave in the html > documentation about compiling with aCC - but we still > had to change some flags. (I know these weren't formal settings and > just an example). > > Is there any chance that there will be a HP-IX-special makefile? It > will make life much easier. :-) > 3. I forgot to mension, that we managed to compile RegEX with SunOS C++ 5.5 both in 32 & 64 bits. There were no errors, BUT in 64 bits when we tried to run the rs/regress test - it failed (something which didn't happen in the 32-bits version). There was also a memory access violation, so even thought the compilation went just fine - apparently the library is not fully 64-bit compatible. What can we do to overcome this problem? Thanks alot, Yaron

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boost::function and managed code
by Russell Hind 07 Jun '04

07 Jun '04

I'm looking for a way to get a boost::function to do a callback to a method of a managed C++ class in VS7.1. Has anyone managed to do this yet? Thanks Russell

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VC60 Compilation error
by mhosni＠softhome.net 07 Jun '04

07 Jun '04

Hi all, while trying to compile the city_visitor.cpp example in the Graph lib with VC60 SP 3, I've got the following error -------------- --------------------Configuration: CityVisitor - Win32 Release-------------------- Compiling... CityVisitor.cpp C:\BOOST\INCLUDE\BOOST-1_31\boost/graph/depth_first_search.hpp(132) : error C2059: syntax error : 'static_cast' C:\BOOST\INCLUDE\BOOST-1_31\boost/graph/depth_first_search.hpp(228) : see reference to function template instantiation 'void __cdecl boost::detail::depth_first_visit_impl(const class boost::adjacency_list<struct boost::vecS,struct boost::vec S,struct boost::undirectedS,struct boost::no_property,struct boost::no_property,struct boost::no_property,struct boost::listS> &,unsigned int,class boost::dfs_visitor<struct std::pair<struct city_arrival,struct std::pair<struct neighbor_cities,struc t finish_city> > > &,class boost::iterator_property_map<enum boost::default_color_type *,struct boost::vec_adj_list_vertex_id_map<struct boost::no_property,unsigned int>,enum boost::default_color_type,enum boost::default_color_type &>,struct boost:: detail::nontruth2)' being compiled Error executing cl.exe. CityVisitor.exe - 1 error(s), 0 warning(s) --------------------------------------------- To be noted, the static_cast operator compiles normally in any other application. The archives of the mailing list contains a similar complain with iterator.hpp (dated Feb 2003 !!) but no solutions were posted in response. Anybody have any idea how to get through this problem Regards, M.Hosni

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boost::bind problem
by Agoston Bejo 05 Jun '04

05 Jun '04

Hi, Please take a look at the code below. The point is that for_each_treenode calls for_each_treenode_child. It seems to me that bind(Print, ref(cout), _1)(&t); is not the same as Print(cout, &t); But if this is the case, how come that for_each_treenode_child(&t, bind(Print, ref(cout), _1)); compiles and works without problem? The compiler I use is VC 7.1. Thx, Gus ---------------------------------------------------------------------- // xBindTemplFuncPtr.cpp : Defines the entry point for the console application. // #include "stdafx.h" #include <iostream> #include <vector> #include <string> #include <boost/bind.hpp> #include <boost/ref.hpp> using namespace std; using namespace boost; template<typename TTree, typename TFunc> void for_each_treenode_child(TTree* t, TFunc f) { for_each(t->children.begin(), t->children.end(), f ); } template<typename TTree, typename TFunc> void for_each_treenode(TTree *t, TFunc f) { void (*thisFunc)(TTree*, TFunc) = for_each_treenode; // COMPILER BUG WORKAROUND - NOT RELEVANT NOW for_each_treenode_child( t, boost::bind(thisFunc, _1, f) ); f(t); } struct Tree { typedef vector<Tree*> Container; typedef Container::const_iterator const_iterator; typedef Container::iterator iterator; const_iterator begin() const { return children.begin(); } const_iterator end() const { return children.end(); } iterator begin() { return children.begin(); } iterator end() { return children.end(); } Tree(const string& sData):data(sData) {} vector<Tree*> children; string data; }; void Print(ostream& out, const Tree* pTree) { out << pTree->data << " "; } void PrintStd(const Tree* pTree) { Print(cout, pTree); } int _tmain(int argc, _TCHAR* argv[]) { Tree t("t"), t1("t1"), t2("t2"), t11("t11"), t12("t12"), t21("t21"); t.children.push_back(&t1); t1.children.push_back(&t11); t1.children.push_back(&t12); t.children.push_back(&t2); t2.children.push_back(&t21); Print(cout, &t); // WORKS bind(Print, ref(cout), _)(&t); // GENERATES ERROR (1) for_each_treenode(&t, bind(Print, ref(cout), _1)); // GENERATES ERROR (2) cout << endl; for_each_treenode(&t, PrintStd); // WORKS cout << endl; for_each_treenode_child(&t, bind(Print, ref(cout), _1)); // WORKS cout << endl; return 0; } ------------------------------------------------------------------------ Error for (1): error C2664: 'boost::_bi::bind_t<R,F,L>::result_type boost::_bi::bind_t<R,F,L>::operator ()<Tree*__w64 >(A1 & ) const' : cannot convert parameter 1 from 'Tree *__w64 ' to 'Tree *__w64 & ' with [ R=void, F=void (__cdecl *)(std::ostream &,const Tree *), L=boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ostr eam>,boost::arg< 1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost:: arg<1>>::B2>, A1=Tree *__w64 ] A reference that is not to 'const' cannot be bound to a non-lvalue Error for (2): c:\Program Files\Microsoft Visual Studio .NET 2003\Vc7\include\boost\bind.hpp(246) : error C2664: 'void (TTree *,TFunc)' : cannot convert parameter 2 from 'boost::_bi::result_traits<R,F>::type' to 'boost::_bi::bind_t<R,F,L>' with [ TTree=Tree, TFunc=boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>> ] and [ R=void, F=void (__cdecl *)(std::ostream &,const Tree *) ] and [ R=void, F=void (__cdecl *)(std::ostream &,const Tree *), L=boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ostr eam>,boost::arg< 1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost:: arg<1>>::B2> ] Expressions of type void cannot be converted to other types c:\Program Files\Microsoft Visual Studio .NET 2003\Vc7\include\boost\bind\bind_template.hpp(33) : see reference to function template instantiation 'R boost::_bi::list2<A1,A2>::operator ()<boost::_bi::bind_t<R,F,L>::result_type,void(__cdecl *)(TTree *,TFunc),boost::_bi::list1<Tree & >>(boost::_bi::type<T>,void,A &)' being compiled with [ R=boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>:: result_type, A1=boost::_bi::list_av_2<boost::arg<1>,boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>>: :B1, A2=boost::_bi::list_av_2<boost::arg<1>,boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>>: :B2, F=void (__cdecl *)(std::ostream &,const Tree *), L=boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ostr eam>,boost::arg< 1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost:: arg<1>>::B2>, TTree=Tree, TFunc=boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>, T=boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,bo ost::arg<1>>::B2>>::result_type, A=boost::_bi::list1<Tree *& > ] c:\Program Files\Microsoft Visual Studio .NET 2003\Vc7\include\algorithm(21) : see reference to function template instantiation 'boost::_bi::bind_t<R,F,L>::result_type boost::_bi::bind_t<R,F,L>::operator ()<std::allocator<_Ty>::value_type>(A1 & )' being compiled with [ R=void, F=void (__cdecl *)(Tree *,boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>), L=boost::_bi::list2<boost::_bi::list_av_2<boost::arg<1>,boost::_bi::bind_t<v oid,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>>: :B1,boost::_bi::list_av_2<boost::arg<1>,boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>>: :B2>, _Ty=Tree *, A1=std::allocator<Tree *>::value_type ] c:\PROG\VCPP\xBindTemplFuncPtr\xBindTemplFuncPtr.cpp(18) : see reference to function template instantiation '_Fn1 std::for_each<std::vector<_Ty>::iterator,TFunc>(_InIt,_InIt,_Fn1)' being compiled with [ _Fn1=boost::_bi::bind_t<void,void (__cdecl *)(Tree *,boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>), boost::_bi::list2<boost::_bi::list_av_2<boost::arg<1>,boost::_bi::bind_t<voi d,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>>: :B1,boost::_bi::list_av_2<boost::arg<1>,boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>>: :B2>>, _Ty=Tree *, TFunc=boost::_bi::bind_t<void,void (__cdecl *)(Tree *,boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>), boost::_bi::list2<boost::_bi::list_av_2<boost::arg<1>,boost::_bi::bind_t<voi d,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>>: :B1,boost::_bi::list_av_2<boost::arg<1>,boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<s td::ostream>,boost::arg<1>>::B2>>>::B2>>, _InIt=std::vector<Tree *>::iterator ] c:\PROG\VCPP\xBindTemplFuncPtr\xBindTemplFuncPtr.cpp(29) : see reference to function template instantiation 'void for_each_treenode_child<TTree,boost::_bi::bind_t<R,F,L>>(TTree *,TFunc)' being compiled with [ TTree=Tree, R=void, F=void (__cdecl *)(Tree *,boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>), L=boost::_bi::list2<boost::_bi::list_av_2<boost::arg<1>,boost::_bi::bind_t<v oid,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>>: :B1,boost::_bi::list_av_2<boost::arg<1>,boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>>: :B2>, TFunc=boost::_bi::bind_t<void,void (__cdecl *)(Tree *,boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>), boost::_bi::list2<boost::_bi::list_av_2<boost::arg<1>,boost::_bi::bind_t<voi d,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>>>: :B1,boost::_bi::list_av_2<boost::arg<1>,boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::refere nce_wrapper<std::ostream>,boost::arg<1>>::B2>>>::B2>> ] c:\PROG\VCPP\xBindTemplFuncPtr\xBindTemplFuncPtr.cpp(68) : see reference to function template instantiation 'void for_each_treenode<Tree,boost::_bi::bind_t<R,F,L>>(TTree *,TFunc)' being compiled with [ R=void, F=void (__cdecl *)(std::ostream &,const Tree *), L=boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ostr eam>,boost::arg< 1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost:: arg<1>>::B2>, TTree=Tree, TFunc=boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>> ] c:\Program Files\Microsoft Visual Studio .NET 2003\Vc7\include\boost\bind.hpp(246) : error C2664: 'void (TTree *,TFunc)' : cannot convert parameter 1 from 'boost::_bi::result_traits<R,F>::type' to 'Tree *' with [ TTree=Tree, TFunc=boost::_bi::bind_t<void,void (__cdecl *)(std::ostream &,const Tree *),boost::_bi::list2<boost::_bi::list_av_2<boost::reference_wrapper<std::ost ream>,boost::arg <1>>::B1,boost::_bi::list_av_2<boost::reference_wrapper<std::ostream>,boost: :arg<1>>::B2>> ] and [ R=void, F=void (__cdecl *)(std::ostream &,const Tree *) ] Expressions of type void cannot be converted to other types

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Boost.Threads && MFC?
by Philip, Tim 04 Jun '04

04 Jun '04

Has anyone ever used Boost.Threads in combination with MFC? MFC requires that threads using MFC functionality be created with AfxCreateThread(). What I'm wondering is if it is safe to create threads using AfxCreateThread() (instead of the Boost.Thread functionality) but then use the Boost.Threads mutexs and locking mechanisms to manage the thread activity. >From my brief perusal of the source it looks like it might work. But I was hoping I could find someone who had actually tried it and might have some experiences to share. :) Any information greatly appreciated! Thanks! Tim.

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BGL: Pajek utility?
by Rui Carvalho 04 Jun '04

04 Jun '04

I'm looking for an utility to import/export graphs between the BGL and Pajek: http://vlado.fmf.uni-lj.si/pub/networks/pajek/ Does anyone know of such utility? Thanks, Rui ___________________________________ Dr. Rui Carvalho Research Fellow The Bartlett School of Graduate Studies 1-19 Torrington Place University College London Gower Street London WC1E 6BT United Kingdom

1 0

Thread usage question.
by Paul Gregory 04 Jun '04

04 Jun '04

Hello all, I am currently using Boost threads in a project I'm working on that involves a server/client type communications system. The project is a 3D renderer, the particular component is the communications between the renderer core, and any number of interested display clients, which are responsible for either displaying or storing the resulting image. Within the main program I have a listener thread that waits for requests from the display clients, and when it recieves one, launches another thread to handle the response. The responder thread can often just construct and send the response immediately. But if the request is for data that hasn't yet been rendered, it needs to wait for the data to be available. The responder is implemented as a class which has an operator() overload for the thread function. I would like for the responder thread to first query the system to see if the data is ready, and if not, block waiting for a signal from the system to indicate it is ready. So I need a way for the thread to 'register' it's interest in a particular data item with the main system, then wait for the signal. I presume there is a neat way of doing this using boost::mutexes and boost::condition's but I can't quite work out how, I freely admint I'm not very experienced when it comes to threaded programming. I've looked at the Boost bounded_buffer.cpp tutorial and it does something similar, but I can't work out how to apply the principles to my situation. Any help is greatly appreciated. Cheers Paul Gregory +---------------------------+---------------------------+ | email: pgregory(a)aqsis.com | Web: http://www.aqsis.com | | ICQ: 156088409 | AIM: aqsis1 | +---------------------------+---------------------------+ | GnuPG: http://aqsis.sourceforge.net/0x9176E46C.asc | +-------------------------------------------------------+

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Some bad links on the web site
by Ross Boylan 04 Jun '04

04 Jun '04

The web site contains a bad link: http://lists.boost.org/mailman/listinfo.cgi/boost-announce directs you to http://lists.boost.org/MailArchives/boost-announce for the archives. That gives a 404 Not Found error. I think there was another bad link related to mailing lists, but I can't find it again. By the way, it would be good if the web site had where to send web-site related queries and bugs on the bottom of every page. As far as I could tell, this list is the place to go.

2 1

Date time Library: ptime and special_values
by Matthew_Schuckmann＠amat.com 04 Jun '04

04 Jun '04

The documentation for the date_time library states that a ptime can be constructed from a special value e.g. ptime(special_values sv) ptime t1(neg_infin); ptime t2(pos_infin); ptime t3(not_a_date_time); However when I try this with the Cygwin GNU compiler I get a no matching function for call error (see errors below) Am I missing something here or is the documentation wrong? Thanks Matt ../../logview.cpp:1843: error: no matching function for call to ` boost::posix_time::ptime::ptime(boost::date_time::special_values)' c:/cygwin/usr/local/include/boost-1_31/boost/date_time/posix_time/ptime.hpp: 32: error: candidates are: boost::posix_time::ptime::ptime(const boost::posix_time::ptime&) c:/cygwin/usr/local/include/boost-1_31/boost/date_time/posix_time/ptime.hpp: 45: error: boost::posix_time::ptime::ptime(const boost::posix_time::int64_time_rep&) c:/cygwin/usr/local/include/boost-1_31/boost/date_time/posix_time/ptime.hpp: 42: error: boost::posix_time::ptime::ptime(boost::gregorian::date) c:/cygwin/usr/local/include/boost-1_31/boost/date_time/posix_time/ptime.hpp: 39: error: boost::posix_time::ptime::ptime(boost::gregorian::date, boost::posix_time::time_duration)

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Compiling with "Visual C++ Toolkit"?
by Wolfgang Meyer 03 Jun '04

03 Jun '04

Has anyone already successfully built Boost with the "Visual C++ Toolkit 2003", aka the free command line version of VC 7.1? I adjusted VC71_ROOT and copied "vcvars32.bat" to "bin". But there are still a lot of errors, the first one being: greg_month.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: __thiscall std ::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >(char const *)" (__imp_??0?$basic_string@DU?$char_tr aits@D@std@@V?$allocator@D@2@@std@@QAE@PBD@Z) referenced in function "public: static class boost::shared _ptr<class std::map<class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char > >,unsigned short,struct std::less<class std::basic_string<char,struct std::char_traits<char>,class std ::allocator<char> > >,class std::allocator<struct std::pair<class std::basic_string<char,struct std::cha r_traits<char>,class std::allocator<char> > const ,unsigned short> > > > __cdecl boost::gregorian::greg_ month::get_month_map_ptr(void)" (?get_month_map_ptr@greg_month@gregorian@boost@@SA?AV?$shared_ptr@V?$map @V?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@GU?$less@V?$basic_string@DU?$char_traits@ D@std@@V?$allocator@D@2@@std@@@2@V?$allocator@U?$pair@$$CBV?$basic_string@DU?$char_traits@D@std@@V?$allo cator@D@2@@std@@G@std@@@2@@std@@@3@XZ) Similar errors occur if I try to use the (successfully built) boost_thread-vc71-mt-1_31.lib with a sample project. Any ideas? Regards, Wolfgang Meyer

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Re: boost regex support for 64-bit
by Itay Eliaz 03 Jun '04

03 Jun '04

Hi, We compiled the latest RegEx library on: 1. SunOS 5.8 Workshop 6: We used the sunpro.mak makefile. Unfortunately, we received many error messages regarding conversions from enum to int and vice versa. 2. HP-UX 11.11 aCC 3.33: We used the generic.mak makeilfe. We got an error regarding dynamic_cast from char*& to char*. In both cases, we didn't run the configure script in libs/config, because if we do, we get many compilation errors (probably because of the #define-s in the created user.hpp). Are you aware of these problems? or are we doing something wrong? Is it imperative that we run the configure script and not use the default user.hpp? On top of that, we managed to overcome the problems I mentioned by simply specifing explicit conversion and casting, and we compiled RegEx on Forte 6 with the 64-bit compilation flag. The compilation worked, but unfortunately, the tests failed. (I mean, the compiled okay and run, but they say that tests.txt contains errors - something that didn't happen when compiling the 32-bit version). What can we do to make it work in 64-bits? Thanks, Yaron "John Maddock" <john(a)johnmaddock.co.uk> wrote in message news:<016d01c43808$4e99e9a0$9cec0352@fuji>... > > does boost regex support 64-bit for SunOS 5.8, HP-UX 11i (native > compilers), > > WIN (MSVC-6) ? > > we are using an old(?) version - regexpp version 3.12. > > Is it recommended to upgrade to the latest version ? > > Is it essential to upgrade to the latest version with relevance to 64-bit > > compilation ? > > 64-bit support should be fine in most recent versions (there was a 64-bit > related bug in one release, but I forget which one now, it was some time ago > now). However the compilers you mention are particularly broken when it > come to compiling any kind of vaguely advanced C++ : The sun compiler should > just about handle regex, as will MSVC 6, but HP aCC is just so broken we've > never been able to port even the most basic Boost libraries to it, sorry... > but see also http://lists.boost.org/MailArchives/boost/msg63570.php > > John.

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Bind and shared_ptr
by Robin 03 Jun '04

03 Jun '04

Hi, The current bind defines the placeholder _1, _2 etc. I was wondering if there is another placeholder that will deference the placeholder if the container is holding pointers instead of copies? Usually I store shared_ptrs in containers instead of direct copies as they are polymorphic class C; // this is our object we are storing typedef boost::shared_ptr<C> CSP; std::vector<CSP> C_List; Now we have a function that operates on C void Operate(C &c); C_List clist; // the list of shared_ptrs to C // this won't compile std::for_each (clist.begin (), clist.end (), boost::bind (Operator,_1)); I have to make an auxillary function to compile void Wrap_Operate (CSP &c) { Operate(*c); } std::for_each (clist.begin (), clist.end (), boost::bind (Wrap_Operate, _1)); Is there to avoid making the additional function and have a placeholder that will dereference directly (eg *_1, *_2)? Can I have the cake and eat it? Robin

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(no subject)
by Mike Feldmeier 02 Jun '04

02 Jun '04

Hi everyone, Could someone please point me in the right direction with this one? : class data { int x; }; class worker { void run(&data d); }; void run_worker(worker& w, data& d) { boost::thread(boost::bind(&worker::run, &my_worker, _1)(boost:ref(my_data))); } void main() { worker my_worker; data my_data; run_worker(my_worker, my_data); } Compiling this yields.. test.cpp(24) : error C2440: 'type cast' : cannot convert from 'boost::_bi::bind_t<R,F,L>::result_type' to 'boost::thread' with [ R=void, F=boost::_mfi::mf1<void,worker,data &>, L=boost::_bi::list2<boost::_bi::list_av_2<worker *,boost::arg<1>>::B1,boost::_bi::list_av_2<worker *,boost::arg<1>>::B2> ] Expressions of type void cannot be converted to other types Can I not bind to functions with a void return type? Changing it to int, produces a similar message. Any help appreciated! Thanks, Mike _________________________________________________________________ FREE pop-up blocking with the new MSN Toolbar get it now! http://toolbar.msn.click-url.com/go/onm00200415ave/direct/01/

2 1

bjam failed to build (mingw)
by krejci.lukas＠volny.cz 02 Jun '04

02 Jun '04

Hi, I have updated from CVS today, set the dev-cpp bin directory into PATH and run: build.bat mingw. This build has failed, attachment '1.txt' contains stdout&stderr outputs. Then I set two additional environment variables: set MINGW_ROOT_DIRECTORY=C:\Dev-Cpp set BOOST_JAM_TOOLSET_ROOT=C:\Dev-Cpp\ and again run: build.bat mingw. This build failed too, attachment '2.txt' contains stdout&stderr outputs. Am I something missing? Have a nice day, L.

4 8

BGL: "degree" with listS
by Bayle Shanks 02 Jun '04

02 Jun '04

I have another question. The following code won't compile. But if you change the first "listS" to "vecS", then it does. I can't find anything in the docs which forbids the use of "degree" with adjacency_list <listS, listS, ... ------------- #include <boost/config.hpp> #include <list> #include <boost/graph/adjacency_list.hpp> using namespace boost; using namespace std; typedef property<vertex_color_t, default_color_type, property<vertex_distance_t,std::size_t, property<vertex_degree_t,std::size_t, property<vertex_in_degree_t, std::size_t, property<vertex_out_degree_t,std::size_t> > > > > VertexProperty; typedef adjacency_list<listS, listS, bidirectionalS, VertexProperty> Graph; typedef boost::graph_traits<Graph>::vertex_descriptor vertexType; int main(int, char*[]) { Graph g; vertexType v0; v0 = add_vertex(g); out_degree(v0, g); } ----------- the compile error is: ----------- /usr/include/boost/iterator/iterator_traits.hpp: In function `void std::distance(_InputIterator, _InputIterator, _Distance&) [with _InputIterator = std::_List_iterator<boost::detail::sei_<size_t, std::_List_iterator<boost::list_edge<size_t, boost::no_property>, boost::list_edge<size_t, boost::no_property>&, boost::list_edge<size_t, boost::no_property>*>, boost::no_property>, const boost::detail::sei_<size_t, std::_List_iterator<boost::list_edge<size_t, boost::no_property>, boost::list_edge<size_t, boost::no_property>&, boost::list_edge<size_t, boost::no_property>*>, boost::no_property>&, const boost::detail::sei_<size_t, std::_List_iterator<boost::list_edge<size_t, boost::no_property>, boost::list_edge<size_t, boost::no_property>&, boost::list_edge<size_t, boost::no_property>*>, boost::no_property>*>, _Distance = size_t]': /usr/include/g++-v3/bits/stl_list.h:307: instantiated from `size_t std::list<_Tp, _Alloc>::size() const [with _Tp = boost::detail::sei_<size_t, std::_List_iterator<boost::list_edge<size_t, boost::no_property>, boost::list_edge<size_t, boost::no_property>&, boost::list_edge<size_t, boost::no_property>*>, boost::no_property>, _Alloc = std::allocator<boost::detail::sei_<size_t, std::_List_iterator<boost::list_edge<size_t, boost::no_property>, boost::list_edge<size_t, boost::no_property>&, boost::list_edge<size_t, boost::no_property>*>, boost::no_property> >]' /usr/include/boost/graph/detail/adjacency_list.hpp:1409: instantiated from `typename Config::degree_size_type boost::out_degree(typename Config::vertex_descriptor, const boost::adj_list_helper<Config, Base>&) [with Config = boost::detail::adj_list_gen<boost::adjacency_list<boost::listS, boost::vecS, boost::bidirectionalS, VertexProperty, boost::no_property, boost::no_property, boost::listS>, boost::vecS, boost::listS, boost::bidirectionalS, VertexProperty, boost::no_property, boost::no_property, boost::listS>::config, Base = boost::bidirectional_graph_helper_with_property<boost::detail::adj_list_gen<boost::adjacency_list<boost::listS, boost::vecS, boost::bidirectionalS, VertexProperty, boost::no_property, boost::no_property, boost::listS>, boost::vecS, boost::listS, boost::bidirectionalS, VertexProperty, boost::no_property, boost::no_property, boost::listS>::config>]' graph2.cpp:26: instantiated from here /usr/include/boost/iterator/iterator_traits.hpp:54: `template<Iterator> struct boost::iterator_category' is not a function, /usr/include/g++-v3/bits/stl_iterator_base_types.h:196: conflict with `template<_Iter> typename std::iterator_traits::iterator_category std::iterator_category(const _Iter&)' /usr/include/g++-v3/bits/stl_iterator_base_funcs.h:102: in call to `iterator_category' ----------- thanks, bayle

1 0

BGL: multigraphs with remove_edge_if
by Bayle Shanks 01 Jun '04

01 Jun '04

Hi, I have a question about the BGL. I'm trying to get remove_edge_if to work with a multigraph. The documentation doesn't seem to prohibit this: http://www.boost.org/libs/graph/doc/MutableGraph.html http://www.boost.org/libs/graph/doc/adjacency_list.html However, the following sample code crashes. It is intended to add two vertices v0 and v1, and to add two edges from v0 to v1, and then to remove all of the edges by passing an always-true predicate to remove_edge_if. ------------------- #include <boost/config.hpp> #include <iostream> // for std::cout #include <utility> // for std::pair #include <boost/utility.hpp> // for boost::tie #include <boost/graph/graph_traits.hpp> // for boost::graph_traits #include <boost/graph/adjacency_list.hpp> #include <boost/graph/graphviz.hpp> using namespace std; using namespace boost; typedef adjacency_list<vecS, vecS, bidirectionalS > UnderlyingGraphType; typedef boost::graph_traits<UnderlyingGraphType>::vertex_descriptor vertexType; typedef boost::graph_traits<UnderlyingGraphType>::edge_descriptor edgeType; class truePredicate { public: truePredicate() {} bool operator()(edgeType e){ cout << "edgePred got " << e <<endl; cout << "about to return true!!!" << endl; return true; } }; int main(int,char*[]) { UnderlyingGraphType G = UnderlyingGraphType(); vertexType v0, v1; edgeType e01_1, e01_2; bool inserted; v0 = boost::add_vertex(G); v1 = boost::add_vertex(G); cout << "v0: " << v0 << endl; cout << "v1: " << v1 << endl; boost::tie(e01_1, inserted) = boost::add_edge(v0,v1,G); cout << "e1: " << e01_1 << endl; cout << "ins1: " << inserted << endl; boost::tie(e01_2, inserted) = boost::add_edge(v0,v1,G); cout << "e2: " << e01_1 << endl; cout << "ins2: " << inserted << endl; boost::write_graphviz(cout,G); boost::remove_edge_if(truePredicate(), G); boost::write_graphviz(cout,G); } ------------------- I'm using Boost 1_31_0 on Debian GNU/Linux with g++-3.0. The result of running the above code on my system is: ------------------- v0: 0 v1: 1 e1: (0,1) ins1: 1 e2: (0,1) ins2: 1 digraph G { 0; 1; 0->1 ; 0->1 ; } edgePred got (0,1) about to return true!!! edgePred got (0,1) about to return true!!! edgePred got (0,1) about to return true!!! edgePred got (4294967295,1919379812) about to return true!!! Segmentation fault ------------------- thanks for your help, bayle p.s. btw, i'm in the process of wrapping BGL for Python using Boost::Python, in case anyone is interested.

1 0

Graph Serialization
by Daniel Z 01 Jun '04

01 Jun '04

Hello, i'm trying to use the serialization library. I manage to serialize simple class, but now i would like to serialize a boost graph, but i can't find how to do it. Anyone can tell me how to begin? Thx. Plus simple, plus fiable, plus rapide : découvrez le nouveau Caramail - http://www.caramail.lycos.fr

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boost::variant: need help with 'get'
by Caleb Epstein 01 Jun '04

01 Jun '04

I'm trying to use the "get" template with boost::variant but can't figure out how to get my compiler to recognize it. Here's a simple test program: --- #include <iostream> #include <cmath> #include <string> #include <boost/variant.hpp> using namespace boost; using namespace std; typedef variant<int, double, string> elem_t; int main () { elem_t pi = M_PI; double d = get (pi); cout << "pi =~ " << d << endl; return 0; } --- But my compiler (gcc 3.3.2) tells me: g++ -I/home/tools/boost-1.31.0 test.cpp -o test test.cpp: In function `int main()': test.cpp:15: error: no matching function for call to `get(elem_t&)' I'm using Boost 1.31.0. Thanks for any help, -- Caleb Epstein | bklyn . org | The Golden Rule of Arts and Sciences: cae at | Brooklyn Dust | He who has the gold makes the rules. bklyn dot org | Bunny Mfg. |

2 2

Boost::tokenizer and reverse iterators
by Jeff Holle 31 May '04

31 May '04

I'm using boost v1_31_0 and gcc v3.3.2 In experimenting with boost::tokenizer to meet a requirement that I have, I've tried hooking it to a reverse iterator. This act produced a run-time error. This is the code: const string test = "One:Two:Three:Four"; typedef char_separator<char> Sep; typedef tokenizer<Sep,string::const_reverse_iterator> Tok; Sep sep(":"); Tok t(test,sep); for (Tok::iterator iter=t.end();iter!=t.begin();++iter) cout << *iter << endl; Executing this produces continous output of "garbage". Switching the ".end()" and ".begin()" references in the for loop doesn't fix this problem. Switching from "const_reverse_iterator" to "const_iterator" produces the following output: One Two Three Four Is there a way to use a reverse iterator with boost:tokenizer?

4 6

BGL: boost::read_graphviz()
by Andreas Scherer 31 May '04

31 May '04

Dear Group, During some initial experiments with the BGL-GraphViz interface, I observed a significant asymmetry between a given DOT graph input with boost::read_graphviz() and output with boost::write_graphviz() (without changing any attributes). Given the input DOT file (which is, of course, much longer with the full set of information) <metro.dot> graph metro { node[ fontname = "luxirr", style = filled, fillcolor = white ]; "Arts et Métiers"; subgraph ligne_1 { node[ fillcolor = "orange" ]; "La Défense/Grande Arch" -- "Esplanade de la Défense"; } } </metro.dot> The elementary BGL program <metro.cxx> #include <boost/graph/graphviz.hpp> int main( void ) { boost::GraphvizGraph g_dot; boost::read_graphviz( "metro.dot", g_dot ); boost::write_graphviz( "metro_boost.dot", g_dot ); } </metro.cxx> transforms this into the output DOT file <metro_boost.dot> graph ligne_1 { node [fillcolor="orange", fontname="luxirr", style="filled"]; subgraph ligne_1 { node [fillcolor="orange", fontname="luxirr", style="filled"]; 1[label="La Défense/Grande Arch"]; 2[label="Esplanade de la Défense"]; 1 -- 2; } 0[label="Arts et Métiers"]; } </metro_boost.dot> It seems that somewhere on the way, the graph and node (and edge) attributes get clobbered. Note that even the graph name "metro" gets replaced by the name of the (last) subgraph "ligne_1", and /all/ node attributes get mixed up. This seems to be somewhat similar to the recent edge-related problem posted by Hideaki Hiraki. I have not (yet) tried to mess with the graphviz parser code, so I am asking here for help. Thanks. Greetings, Andreas

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