[Boost-users] Example program that fails to compile (boost::bind and boost::function called for collection)

Subject: [Boost-users] Example program that fails to compile (boost::bind and boost::function called for collection)
From: Archie14 (admin_at_[hidden])
Date: 2009-01-27 14:21:48

Below is a a test program with the purpose of calling member function for each 
element of the collection. Argument of this member function is a 
boost::function.
I put compilation error after the source code. 

Any help will be greatly appreciated.

#include <boost/bind.hpp>
#include <boost/function.hpp>
#include <boost/ptr_container/ptr_vector.hpp>

typedef boost::function<void (int, int, const char*) > delegate; 

class A : public boost::noncopyable
{
public:
        commandhandler(delegate& f) {}
};

template <typename C> class Acoll
{
        typedef boost::ptr_vector<C> ptr_container;
        ptr_container m_data;
public:
        typedef C CLIENT;
        ptr_container& operator() (){return m_data;}
};

template <typename CLIENTS> class Test
{
        CLIENTS& m_clients;
public:
        delegate dosomething;
        Test(CLIENTS& val) :  m_clients(val) {}
        void run()
        {
                std::for_each(m_clients().begin(), m_clients().end(), 
                        boost::bind(&CLIENTS::CLIENT::commandhandler, 
boost::ref(dosomething), _1 ));
        }
};

int _tmain(int argc, _TCHAR* argv[])
{
        Acoll<A> coll;
        Test<Acoll<A> > test(coll);
        test.run();
        return 0;
}

Error:

1>e:\libraries\boost\boost_1_37_0\boost\bind.hpp(292) : error C2664: 'R 
boost::_mfi::mf1<R,T,A1>::operator ()<boost::function<Signature>>(const U &,A1) 
const' : cannot convert parameter 2 from 'A' to 'boost::function<Signature> '
1>        with
1>        [
1>            R=void,
1>            T=A,
1>            A1=delegate &,
1>            Signature=void (int,int,const char *),
1>            U=delegate
1>        ]
1>        and
1>        [
1>            Signature=void (int,int,const char *)
1>        ]
1>        e:\libraries\boost\boost_1_37_0\boost\bind\bind_template.hpp(32) : 
see reference to function template instantiation 'void 
boost::_bi::list2<A1,A2>::operator ()<F,boost::_bi::list1<A 
&>>(boost::_bi::type<T>,F &,A &,int)' being compiled
1>        with
1>        [
1>            A1=boost::reference_wrapper<delegate>,
1>            A2=boost::arg<1>,
1>            F=boost::_mfi::mf1<void,A,delegate &>,
1>            T=void,
1>            A=boost::_bi::list1<A &>
1>        ]
1>        e:\program files\microsoft visual studio 9.0\vc\include\algorithm(29) 
: see reference to function template instantiation 'void 
boost::_bi::bind_t<R,F,L>::operator ()<T>(A1 &)' being compiled
1>        with
1>        [
1>            R=void,
1>            F=boost::_mfi::mf1<void,A,delegate &>,
1>            
L=boost::_bi::list2<boost::reference_wrapper<delegate>,boost::arg<1>>,
1>            T=A,
1>            A1=A
1>        ]
1>        c:\test\t458\t458\t458.cpp(39) : see reference to function template 
instantiation '_Fn1 
std::for_each<boost::void_ptr_iterator<VoidIter,T>,boost::_bi::bind_t<R,F,L>>(_
InIt,_InIt,_Fn1)' being compiled
1>        with
1>        [
1>            _Fn1=boost::_bi::bind_t<void,boost::_mfi::mf1<void,A,delegate 
&>,boost::_bi::list2<boost::reference_wrapper<delegate>,boost::arg<1>>>,
1>            VoidIter=std::_Vector_iterator<void *,std::allocator<void *>>,
1>            T=A,
1>            R=void,
1>            F=boost::_mfi::mf1<void,A,delegate &>,
1>            
L=boost::_bi::list2<boost::reference_wrapper<delegate>,boost::arg<1>>,
1>            _InIt=boost::void_ptr_iterator<std::_Vector_iterator<void 
*,std::allocator<void *>>,A>
1>        ]
1>        c:\test\t458\t458\t458.cpp(37) : while compiling class template 
member function 'void Test<CLIENTS>::run(void)'
1>        with
1>        [
1>            CLIENTS=Acoll<A>
1>        ]
1>        c:\test\t458\t458\t458.cpp(47) : see reference to class template 
instantiation 'Test<CLIENTS>' being compiled
1>        with
1>        [
1>            CLIENTS=Acoll<A>
1>        ]