std::is_class

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Defined in header `<type_traits>`

template< class T > struct is_function;		(C++11 feature)

If T is function type (but not std::function, lambda expression or another callable object type), provides the member constant value equal true. For any other type, value is false.

Inherited from std::integral_constant

Member constants


`value`	true if `T` is a function type , false otherwise (public static member constant)

Member functions


`operator bool`	converts the object to bool, returns `value` (public member function)

Member types


Type	Definition

`value_type`	`bool`

`type`	std::integral_constant<bool, value>

[edit] Example

#include <iostream>
#include <type_traits>
 
struct A {};
 
int f()
{
}
 
int main() 
{
    std::cout << std::boolalpha;
    std::cout << std::is_function<A>::value << '\n';
    std::cout << std::is_function<int(int)>::value << '\n';
    std::cout << std::is_function<decltype(f)>::value << '\n';
    std::cout << std::is_function<int>::value << '\n';
}

Output:

true
true
false
false

[edit] See also

is_object (C++11)

checks if a type is object type
(class template)

is_class (C++11)

checks if a type is a class type (but not union type)
(class template)