std::equal_to<void>

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

std::equal_to < void > is a specialization of std::equal_to

Nested types

Nested type Definition
is_transparent unspecified

Member functions

operator()
 tests if the two arguments compare equal
(public member function)

std::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 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 a = 0, b = 8;
    std::equal_to<> equal{};
    static_assert(equal(a, a));
    static_assert(!equal(a, b));
}
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