std::ranges::greater_equal
Defined in header <functional> |
||
---|---|---|
struct greater_equal; |
(since C++20) |
Function object for performing comparisons. Deduces the parameter types of the function call operator from the arguments (but not the return type).
Implementation-defined strict total order over pointers
The function call operator yields the implementation-defined strict total order over pointers if the <
operator between arguments invokes a built-in comparison operator for a pointer, even if the built-in <
operator does not.
The implementation-defined strict total order is consistent with the partial order imposed by built-in comparison operators (<=>
, <
, >
, <=
, and >=
), and consistent among following standard function objects:
-
std::less
,std::greater
,std::less_equal
, andstd::greater_equal
, when the template argument is a pointer type orvoid
-
std::ranges::equal_to
,std::ranges::not_equal_to
,std::ranges::less
,std::ranges::greater
,std::ranges::less_equal
,std::ranges::greater_equal
, andstd::compare_three_way
Member types
Member type | Definition |
---|---|
is_transparent |
/* unspecified */ |
Member functions
operator()
|
checks if the first argument is greater than or equal to the second (public member function) |
std::ranges::greater_equal::operator()
template< class T, class U > requires std::totally_ordered_with<T, U> // with different semantic requirements constexpr bool operator()(T&& t, U&& u) const; |
Compares t
and u
. Equivalent to return !ranges::less{}(std::forward<T>(t), std::forward<U>(u));
.
Notes
Unlike std::greater_equal
, std::ranges::greater_equal
requires all six comparison operators <
, <=
, >
, >=
, ==
and !=
to be valid (via the totally_ordered_with
constraint) and is entirely defined in terms of std::ranges::less
.
Example
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 3530 | C++20 | syntactic checks were relaxed while comparing pointers | only semantic requirements relaxed |
See also
function object implementing x >= y (class template) |
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