std::greater_equal<void>

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< cpp‎ | utility‎ | functional
Utilities library
Function objects
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greater_equal<>
(C++14)
(C++14)
(C++14)
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(C++14)

Old binders and adaptors
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Defined in header <functional>
template <>
class greater_equal< void > ;
(since C++14)

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

Nested types

Nested type Definition
is_transparent unspecified

Member functions

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

std::greater_equal<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 <functional>
#include <initializer_list>
 
constexpr bool strictly_not_negative(int lhs)
{
    return std::greater_equal<>()(lhs, 0);
}
 
int main()
{
    constexpr int low = 0, high = 8;
    std::greater_equal<> greater_equal{};
    static_assert(greater_equal(high, low));
    static_assert(greater_equal(low, low));
 
    static constexpr auto arr = {-1, 0, 1, 2, 3, 4};
    static_assert(!std::all_of(arr.begin(), arr.end(), strictly_not_negative));
    static_assert(std::all_of(arr.begin() + 1, arr.end(), strictly_not_negative));
}

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