function_traits.cpp

#include <iostream>
#include <tuple>
#include <string>
#include <typeinfo>
#include <memory>
#include <cxxabi.h>

namespace extra {
	template <typename... Types>
	struct TypeInfoExtractor;
	
	template <typename Head, typename... Types>
	struct TypeInfoExtractor<Head, Types...> {
		template <typename Func>
		static void extract(const Func &f) {
			f(typeid(Head));
			
			TypeInfoExtractor<Types...>::extract(f);
		}
	};
	
	template <>
	struct TypeInfoExtractor<> {
		template <typename Func>
		static void extract(const Func &f) {
			// nop
		}
	};
	
	template <typename T>
	struct function_traits;

	template <typename Return, typename... Params>
	struct function_traits<Return(Params...)> {
		static const size_t arity = sizeof...(Params);

		typedef Return return_type;

		typedef std::tuple<Params...> parameter_tuple;

		template <typename Func>
		static void extract_type_info(const Func &f) {
			TypeInfoExtractor<Params...>::extract(f);
		}
	};
}

void f(int, int, float, char*, char[10]) { }

int main() {
	typedef extra::function_traits<decltype(f)> f_traits;

	f_traits::extract_type_info([] (const std::type_info &rtti) {
		std::unique_ptr<char, void(*)(void*)> realname(abi::__cxa_demangle(rtti.name(), 0, 0, nullptr), free);
		
		std::cout << realname.get() << std::endl;
	});
}