class template
<type_traits>

std::is_volatile

template <class T> struct is_volatile;
Is volatile-qualified

Trait class that identifies whether T is a volatile-qualified type.

It inherits from integral_constant as being either true_type or false_type, depending on whether T is volatile.

Template parameters

T
A type.

Member types

Inherited from integral_constant:
member typedefinition
value_typebool
typeeither true_type or false_type

Member constants

Inherited from integral_constant:
member constantdefinition
valueeither true or false

Member functions

Inherited from integral_constant:
operator bool
Returns value (public member function )

Example

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// is_volatile example
#include <iostream>
#include <type_traits>

int main() {
  std::cout << std::boolalpha;
  std::cout << "is_volatile:" << std::endl;
  std::cout << "int: " << std::is_volatile<int>::value << std::endl;
  std::cout << "volatile int: " << std::is_volatile<volatile int>::value << std::endl;
  std::cout << "volatile int*: " << std::is_volatile<volatile int*>::value << std::endl;
  std::cout << "int* volatile: " << std::is_volatile<int* volatile>::value << std::endl;
  return 0;
}


Output:
is_volatile:
int: false
volatile int: true
volatile int*: false
int* volatile: true

See also

is_const
Is const-qualified (class template )
is_signed
Is signed type (class template )
is_unsigned
Is unsigned type (class template )

C++

<type_traits>