std::is_volatile

Defined in header `<type_traits>`
template< class T > struct is_volatile;		(since C++11)

If T is a volatile-qualified type (that is, volatile, or const volatile), provides the member constant value equal true. For any other type, value is false.

Inherited from std::integral_constant

Member constants

value

[static]

true if T is a volatile-qualified 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] Possible implementation

template<class T> struct is_volatile             : std::false_type {};
template<class T> struct is_volatile<volatile T> : std::true_type {};

[edit] Example

Run this code

#include <iostream>
#include <type_traits>
 
int main() 
{
    std::cout << std::boolalpha;
    std::cout << std::is_volatile<int>::value << '\n';
    std::cout << std::is_volatile<volatile int>::value  << '\n';
}

Output:

false
true

[edit] See also

is_const

(C++11)

checks if a type is const-qualified
(class template)

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