std::equal_to - cppreference.com (original) (raw)

| | | | | ---------------------------------- | | ------------- | | template<> class equal_to<void>; | | (since C++14) |

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

Contents

• 1 Nested types
• 2 Member functions
• 3 std::equal_to::operator()
  • 3.1 Parameters
  • 3.2 Return value
  • 3.3 Example

[edit] Nested types

[edit] Member functions

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

std::equal_to::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

Return value

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

[edit] Example

#include   int main() { constexpr int a = 0, b = 8; std::equal_to<> equal{}; static_assert(equal(a, a)); static_assert(!equal(a, b)); }