- Boost-users - lists.boost.org

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.

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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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