<type_traits>

类模板
<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.

它继承自 integral_constant,并根据Tis volatile.

模板参数

T
一个类型。

成员类型

Inherited from integral_constant
成员类型定义
value_typebool
类型true_type 或 false_type

成员常量

Inherited from integral_constant
成员常量定义
trueorfalse

成员函数

Inherited from integral_constant

示例

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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;
}

输出
is_volatile:
int: false
volatile int: true
volatile int*: false
int* volatile: true


另见