is_function Class

Tests if type is a function type.

template<class Ty>
    struct is_function;

Parameters

  • Ty
    The type to query.

Remarks

An instance of the type predicate holds true if the type Ty is a function type, otherwise it holds false.

Example

 

// std_tr1__type_traits__is_function.cpp 
// compile with: /EHsc 
#include <type_traits> 
#include <iostream> 
 
struct trivial 
    { 
    int val; 
    }; 
 
struct functional 
    { 
    int f(); 
    }; 
 
int main() 
    { 
    std::cout << "is_function<trivial> == " << std::boolalpha 
        << std::is_function<trivial>::value << std::endl; 
    std::cout << "is_function<functional> == " << std::boolalpha 
        << std::is_function<functional>::value << std::endl; 
    std::cout << "is_function<float()> == " << std::boolalpha 
        << std::is_function<float()>::value << std::endl; 
 
    return (0); 
    } 
 
is_function<trivial> == false
is_function<functional> == false
is_function<float()> == true

Requirements

Header: <type_traits>

Namespace: std

See Also

Reference

<type_traits>

is_object Class