std::greater<void>

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< cpp‎ | utility‎ | functional
 
 
Utilities library
General utilities
Relational operators (deprecated in C++20)
 
Function objects
Function invocation
(C++17)(C++23)
Identity function object
(C++20)
Transparent operator wrappers
(C++14)
(C++14)
(C++14)
(C++14)  
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)
(C++14)
greater<>
(C++14)
(C++14)

Old binders and adaptors
(until C++17*)
(until C++17*)
(until C++17*)
(until C++17*)  
(until C++17*)
(until C++17*)(until C++17*)(until C++17*)(until C++17*)
(until C++20*)
(until C++20*)
(until C++17*)(until C++17*)
(until C++17*)(until C++17*)

(until C++17*)
(until C++17*)(until C++17*)(until C++17*)(until C++17*)
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Defined in header <functional>
template<>
class greater<void>;
(since C++14)

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

Nested types

Nested type Definition
is_transparent unspecified

Member functions

operator()
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