std::not_equal_to<void>

 

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运算符包装器 plus minus negate multiplies divides modulus bit_and bit_or bit_not (C++14)   bit_xor equal_to not_equal_to greater less greater_equal less_equal logical_and logical_or logical_not	透明运算符包装器 plus<> (C++14) minus<> (C++14) negate<> (C++14) multiplies<> (C++14)   divides<> (C++14) modulus<> (C++14) bit_and<> (C++14) bit_or<> (C++14) bit_not<> (C++14) bit_xor<> (C++14) equal_to<> (C++14) not_equal_to<> (C++14) greater<> (C++14) less<> (C++14) greater_equal<> (C++14) less_equal<> (C++14) logical_and<> (C++14) logical_or<> (C++14) logical_not<> (C++14)
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unary_function (until C++17*) binary_function (until C++17*) ptr_fun (until C++17*) pointer_to_unary_function (until C++17*) pointer_to_binary_function (until C++17*)   mem_fun (until C++17*) mem_fun_tmem_fun1_tconst_mem_fun_tconst_mem_fun1_t (until C++17*)(until C++17*)(until C++17*)(until C++17*) not1 (until C++20*) not2 (until C++20*)	binder1stbinder2nd (until C++17*)(until C++17*) bind1stbind2nd (until C++17*)(until C++17*) mem_fun_ref (until C++17*) mem_fun_ref_tmem_fun1_ref_tconst_mem_fun_ref_tconst_mem_fun1_ref_t (until C++17*)(until C++17*)(until C++17*)(until C++17*) unary_negate (until C++20*) binary_negate (until C++20*)

 

定义在头文件 <functional> 中
template<> class not_equal_to<void>;		(自 C++14 起)

std::not_equal_to<void> 是 std::not_equal_to 的特化，参数和返回类型推导出来。

嵌套类型

嵌套类型	定义
is_transparent	未指定

成员函数

operator()

测试两个参数是否不等于 (公有成员函数)

std::not_equal_to<void>::operator()

template< class T, class U > constexpr auto operator()( T&& lhs, U&& rhs ) const     -> decltype(std::forward<T>(lhs) != std::forward<U>(rhs));

返回 lhs 和 rhs 之间的不等比较结果。

参数

lhs, rhs

-

要比较的值

返回值

std::forward<T>(lhs) != std::forward<U>(rhs).

示例

运行此代码

#include <functional>
 
int main()
{
    constexpr int p = 0, q = 8;
    std::not_equal_to<> not_equal{};
    static_assert(!not_equal(p, p));
    static_assert(not_equal(p, q));
}