Populating the std::map of boost::function with bo

I would like to create a key-value data structure that would be useful for responding to the events of string matching to regex patterns. So I am trying to work it out with a Boost library:

#include <boost/regex.hpp>
#include <boost/function.hpp>
#include <boost/bind.hpp>
#include <boost/assign.hpp>
#include <map>

typedef std::map<boost::regex, boost::function<void(void)> > regex_callback;

void SuOpenedCallback()
{
}

void SuClosedCallback()
{
}


int main(int argc, char** argv)
{
    //Don't pay attention to these definitions... 
    boost::regex su_opened  ("^(\\w+)\\s(\\d+)\\s([\\d:]+)\\s(\\w+)\\s"
                            "su: pam_unix\\(su:session\\): session opened for user{1}\\s([\\w\\d]+)\\sby{1}\\s([\\w\\d]+)\\(uid=([\\d]+)\\)$"); 
    boost::regex su_closed  ("^(\\w+)\\s(\\d+)\\s([\\d:]+)\\s(\\w+)\\s"
                            "su: pam_unix\\(su:session\\): session closed for user{1}\\s([\\w\\d]+)$");

    //Compilation error:
    regex_callback resolver = boost::assign::map_list_of<boost::regex, boost::function<void(void)> >
        (su_opened, boost::bind(&SuOpenedCallback))
        (su_closed, boost::bind(&SuClosedCallback));

//...

}

When I try to compile it (unfortunately I am forced to use quite old software - gcc 4.4.7, boost 1.41, therefore C++11 support is very limited):

 g++ boost_regexp.cpp -o test -lboost_regex -std=c++0x

compilation fails with this error:

boost_regexp.cpp: In function ‘int main(int, char**)’: boost_regexp.cpp:58: error: ambiguous overload for ‘operator=’ in ‘resolver = boost::assign::map_list_of(const Key&, const T&) [with Key = boost::regex, T = boost::_bi::bind_t<void, void (*)(), boost::_bi::list0>](((const boost::_bi::bind_t<void, void (*)(), boost::_bi::list0>&)((const boost::_bi::bind_t<void, void (*)(), boost::_bi::list0>*)(& boost::bind [with R = void](SuOpenedCallback))))).boost::assign_detail::generic_list<T>::operator() [with U = boost::regex, U0 = boost::_bi::bind_t<void, void (*)(), boost::_bi::list0>, T = std::pair<boost::basic_regex<char, boost::regex_traits<char, boost::cpp_regex_traits<char>, boost::_bi::bind_t<void, void (*)(), boost::_bi::list0>](((const boost::regex&)((const boost::regex*)(& su_closed))), ((const boost::_bi::bind_t<void, void (*)(), boost::_bi::list0>&)((const boost::_bi::bind_t<void, void (*)(), boost::_bi::list0>*)(& boost::bind [with R = void](SuClosedCallback)))))’ /usr/lib/gcc/x86_64-redhat-linux/4.4.7/../../../../include/c++/4.4.7/bits/stl_map.h:251: note: candidates are: std::map<_Key, _Tp, _Compare, _Alloc>& std::map<_Key, _Tp, _Compare, _Alloc>::operator=(const std::map<_Key, _Tp, _Compare, _Alloc>&) [with _Key = boost::basic_regex<char, boost::regex_traits<char, boost::cpp_regex_traits<char>, _Tp = boost::function<void()>, _Compare = std::less<boost::basic_regex<char, boost::regex_traits<char, boost::cpp_regex_traits<char>, _Alloc = std::allocator<std::pair<const boost::basic_regex<char, boost::regex_traits<char, boost::cpp_regex_traits<char>, boost::function<void()>] /usr/lib/gcc/x86_64-redhat-linux/4.4.7/../../../../include/c++/4.4.7/bits/stl_map.h:266: note: std::map<_Key, _Tp, _Compare, _Alloc>& std::map<_Key, _Tp, _Compare, _Alloc>::operator=(std::map<_Key, _Tp, _Compare, _Alloc>&&) [with _Key = boost::basic_regex<char, boost::regex_traits<char, boost::cpp_regex_traits<char>, _Tp = boost::function<void()>, _Compare = std::less<boost::basic_regex<char, boost::regex_traits<char, boost::cpp_regex_traits<char>, _Alloc = std::allocator<std::pair<const boost::basic_regex<char, boost::regex_traits<char, boost::cpp_regex_traits<char>, boost::function<void()>] /usr/lib/gcc/x86_64-redhat-linux/4.4.7/../../../../include/c++/4.4.7/bits/stl_map.h:286: note: std::map<_Key, _Tp, _Compare, _Alloc>& std::map<_Key, _Tp, _Compare, _Alloc>::operator=(std::initializer_list<std::pair<const _Key, _Tp>) [with _Key = boost::basic_regex<char, boost::regex_traits<char, boost::cpp_regex_traits<char>, _Tp = boost::function<void()>, _Compare = std::less<boost::basic_regex<char, boost::regex_traits<char, boost::cpp_regex_traits<char>, _Alloc = std::allocator<std::pair<const boost::basic_regex<char, boost::regex_traits<char, boost::cpp_regex_traits<char>, boost::function<void()>] make: *** [all] Error 1

Seems like my problem is close to this one, however, it does not inspire me. It would be nice if someone could show me the mistake.

ANSWER As @sehe has mentioned, this code is correct for up-to-date versions of gcc but cannot be handled with gcc 4.4. Unfortunately for me.

I'd say that should just compile.

You might try the more direct approach (without bind) though, which is probably (a lot) easier on the compiler:

regex_callback resolver = boost::assign::map_list_of<boost::regex, boost::function<void(void)> >
    (su_opened, &SuOpenedCallback)
    (su_closed, &SuClosedCallback);

EDIT Since that didn't work, try making it more explicit still:

typedef boost::function<void(void)> Func;

regex_callback resolver = boost::assign::map_list_of<boost::regex, Func >
    (su_opened, Func(boost::bind(&SuOpenedCallback)))
    (su_closed, Func(boost::bind(&SuClosedCallback)));

// or:
regex_callback resolver = boost::assign::map_list_of<boost::regex, Func >
    (su_opened, Func(&SuOpenedCallback))
    (su_closed, Func(&SuClosedCallback));