std::experimental::ranges::greater

< cpp‎ | experimental‎ | ranges

Defined in header `<experimental/ranges/functional>`
template< class T = void > requires StrictTotallyOrdered<T> \|\| Same<T, void> \|\| /* < on two const T lvalues invokes a built-in operator comparing pointers */ struct greater;		(ranges TS)
template<> struct greater<void>;		(ranges TS)

Function object for performing comparisons. The primary template invokes operator< on const lvalues of type T with the argument order inverted. The specialization greater<void> deduces the parameter types of the function call operator from the arguments (but not the return type).

All specializations of greater are Semiregular.

Member types

Member type	Definition
`is_transparent` (member only of `greater<void>` specialization)	/* unspecified */

Member functions

operator()

checks if the first argument is greater than the second
(public member function)

std::experimental::ranges::greater::operator()

constexpr bool operator()(const T& x, const T& y) const;	(1)	(member only of primary `greater<T>` template)
template< class T, class U > requires StrictTotallyOrderedWith<T, U> \|\| /* std::declval<T>() < std::declval<U>() resolves to a built-in operator comparing pointers */ constexpr bool operator()(T&& t, U&& u) const;	(2)	(member only of `greater<void>` specialization)

1) Compares x and y. Equivalent to return ranges::less<>{}(y, x);.

2) Compares t and u. Equivalent to return ranges::less<>{}(std::forward<U>(u), std::forward<T>(t));.

Notes

Unlike std::greater, ranges::greater requires all six comparison operators <, <=, >, >=, == and != to be valid (via the StrictTotallyOrdered and StrictTotallyOrderedWith constraints) and is entirely defined in terms of ranges::less. However, the implementation is free to use operator> directly, because those concepts require the results of the comparison operators to be consistent.

Example