<type_traits>

类模板
<type_traits>

std::is_member_function_pointer

template <class T> struct is_member_function_pointer;
Is member function pointer

Trait class that identifies whether T is a pointer to a non-static member function.

它继承自 integral_constant,其值为 true_typefalse_type

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_member_function_pointer example
#include <iostream>
#include <type_traits>

struct A { void fn() {}; };

int main() {
  void(A::*pt)() = &A::fn;
  std::cout << std::boolalpha;
  std::cout << "is_member_function_pointer:" << std::endl;
  std::cout << "A*: " << std::is_member_function_pointer<A*>::value << std::endl;
  std::cout << "void(A::*)(): " << std::is_member_function_pointer<void(A::*)()>::value << std::endl;
  std::cout << "decltype(pt): " << std::is_member_function_pointer<decltype(pt)>::value << std::endl;
  return 0;
}

输出
is_member_object_pointer:
A*: false
int A::*: true
decltype(pt): true


另见