std::greater<void> - cppreference.com

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`template<> class greater<void>;`		(since C++14)

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

Nested types

Member functions

tests if lhs compares greater than rhs
(public member function)

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

Parameters

lhs, rhs

values to compare

Return value

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

If a built-in operator comparing pointers is called, the result is consistent with the implementation-defined strict total order over pointers.

Exceptions

May throw implementation-defined exceptions.

Example

#include <algorithm>
#include <cstdint>
#include <functional>

constexpr bool strictly_positive(int lhs)
{
    return std::greater<>()(lhs, 0);
}

int main()
{
    constexpr std::int64_t low = 0B11;
    constexpr std::uint16_t high = 0X11;
    std::greater<> greater{};
    static_assert(greater(high, low));

    constexpr static auto arr = {0, 1, 2, 3, 4, 5};
    static_assert(!std::all_of(arr.begin(), arr.end(), strictly_positive));
    static_assert(std::all_of(arr.begin() + 1, arr.end(), strictly_positive));
}

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR	Applied to	Behavior as published	Correct behavior
LWG 2562	C++98	the pointer total order might be inconsistent	guaranteed to be consistent