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#include <type_traits>
#include <typeinfo>
#include <iostream>
#include <functional>
using namespace std;
 
template<typename T> void test(){
	cout<<typeid(typename function<T>::result_type).name()<<endl;		//works
	cout<<typeid(typename std::result_of<T>::type).name()<<endl;		//compile-time error here.
}
 
template<typename T, typename std::enable_if< std::is_pointer<T>::value&&std::is_function<typename std::remove_pointer<T>::type>::value, int >::type =0>
void push(T val){
	test<typename std::remove_pointer<T>::type>();
}
 
int main(){
	push(main);
}
 
 
 
Error is:
 
g++ -O0 -g3 -Wall -c -fmessage-length=0 -std=c++0x -MMD -MP -MF"main.d" -MT"main.d" -o "main.o" "../main.cpp"
In file included from ../main.cpp:1:0:
/usr/include/c++/4.6/type_traits: In instantiation of ‘std::_Result_of_impl<false, false, int>’:
/usr/include/c++/4.6/type_traits:1215:12:   instantiated from ‘std::result_of<int()>’
../main.cpp:9:2:   instantiated from ‘void test() [with T = int()]’
../main.cpp:14:2:   instantiated from ‘void push(T) [with T = int (*)(), typename std::enable_if<(std::is_pointer<_Functor>::value && std::is_function<typename std::remove_pointer<_Functor>::type>::value), int>::type <anonymous> = 0]’
../main.cpp:18:11:   instantiated from here
/usr/include/c++/4.6/type_traits:1192:9: error: ‘std::declval [with _Tp = int, typename std::add_rvalue_reference<_Tp>::type = int&&]()’ cannot be used as a function

prog.cpp:25:49: error: invalid suffix "x" on integer constant
prog.cpp:27:1: error: stray '\342' in program
prog.cpp:27:1: error: stray '\200' in program
prog.cpp:27:1: error: stray '\230' in program
prog.cpp:27:1: error: stray '\342' in program
prog.cpp:27:1: error: stray '\200' in program
prog.cpp:27:1: error: stray '\231' in program
prog.cpp:28:1: error: stray '\342' in program
prog.cpp:28:1: error: stray '\200' in program
prog.cpp:28:1: error: stray '\230' in program
prog.cpp:28:1: error: stray '\342' in program
prog.cpp:28:1: error: stray '\200' in program
prog.cpp:28:1: error: stray '\231' in program
prog.cpp:29:1: error: stray '\342' in program
prog.cpp:29:1: error: stray '\200' in program
prog.cpp:29:1: error: stray '\230' in program
prog.cpp:29:1: error: stray '\342' in program
prog.cpp:29:1: error: stray '\200' in program
prog.cpp:29:1: error: stray '\231' in program
prog.cpp:30:1: error: stray '\342' in program
prog.cpp:30:1: error: stray '\200' in program
prog.cpp:30:1: error: stray '\230' in program
prog.cpp:30:1: error: stray '\342' in program
prog.cpp:30:1: error: stray '\200' in program
prog.cpp:30:1: error: stray '\231' in program
prog.cpp:32:1: error: stray '\342' in program
prog.cpp:32:1: error: stray '\200' in program
prog.cpp:32:1: error: stray '\230' in program
prog.cpp:32:1: error: stray '\342' in program
prog.cpp:32:1: error: stray '\200' in program
prog.cpp:32:1: error: stray '\231' in program
prog.cpp:23:1: error: 'Error' does not name a type
In file included from prog.cpp:4:0:
/usr/lib/gcc/i686-pc-linux-gnu/4.5.1/../../../../include/c++/4.5.1/functional: In instantiation of 'std::result_of<int()>':
prog.cpp:9:2:   instantiated from 'void test() [with T = int()]'
prog.cpp:14:2:   instantiated from 'void push(T) [with T = int (*)(), typename std::enable_if<(std::is_pointer<_Tp>::value && std::is_function<typename std::remove_pointer<_Tp>::type>::value), int>::type <anonymous> = 0]'
prog.cpp:18:11:   instantiated from here
/usr/lib/gcc/i686-pc-linux-gnu/4.5.1/../../../../include/c++/4.5.1/functional:180:9: error: 'std::declval [with _Tp = int, typename std::add_rvalue_reference<_Tp>::type = int&&]()' cannot be used as a function

Standard output is empty