Question

I am trying to defining a specific function pointer type to be used in my calls of boost::bind to resolve issue related to function overloaded not recognized ( by calling static_cast ). I am defining that typedef explicitly for resolving ambiguity on std::string::compare.

When I write this function I got errors.

   typedef int(std::string* resolve_type)(const char*)const;

Do you know what’s wrong with this typedef?

Answer 1

I think you want this.

typedef int(std::string::*resolve_type)(const char*) const;

Example.

#include <iostream>
#include <functional>

typedef int(std::string::*resolve_type)(const char*)const;

int main()
{
   resolve_type resolver = &std::string::compare;
   std::string s = "hello";
   std::cout << (s.*resolver)("hello") << std::endl;
}

http://liveworkspace.org/code/4971076ed8ee19f2fdcabfc04f4883f8

And example with bind

#include <iostream>
#include <functional>

typedef int(std::string::*resolve_type)(const char*)const;

int main()
{
   resolve_type resolver = &std::string::compare;
   std::string s = "hello";
   auto f = std::bind(resolver, s, std::placeholders::_1);
   std::cout << f("hello") << std::endl;
}

http://liveworkspace.org/code/ff1168db42ff5b45042a0675d59769c0