std::not_equal_to<void>

 

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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*)

 

Defined in header <functional>
template<> class not_equal_to<void>;		(since C++14)

std::not_equal_to<void> is a specialization of std::not_equal_to with parameter and return type deduced.

Nested types

Nested type	Definition
is_transparent	unspecified

Member functions

operator()

tests if the two arguments do not compare equal (public member function)

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));

Returns the result of non-equality comparison between lhs and rhs.

Parameters

lhs, rhs

-

values to compare

Return value

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

Example

Run this code

#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));
}