std:: less_equal

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Utilities library
General utilities
Relational operators (deprecated in C++20)
Function objects
Function invocation
(C++17) (C++23)
Identity function object
(C++20)
Old binders and adaptors
( until C++17* )
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( until C++17* )
( until C++17* ) ( until C++17* ) ( until C++17* ) ( until C++17* )
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( 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 T >
struct less_equal ;
(until C++14)
template < class T = void >
struct less_equal ;
(since C++14)

Function object for performing comparisons. The main template invokes operator <= on type T .

Specializations

function object implementing x <= y deducing parameter and return types
(class template specialization)

Member types

Type Definition
result_type (deprecated in C++17) (removed in C++20) bool
first_argument_type (deprecated in C++17) (removed in C++20) T
second_argument_type (deprecated in C++17) (removed in C++20) T

These member types are obtained via publicly inheriting std:: binary_function < T, T, bool > .

(until C++11)

Member functions

operator()
checks if the first argument is less than or equal to the second
(public member function)

std::less_equal:: operator()

bool operator ( ) ( const T & lhs, const T & rhs ) const ;
(constexpr since C++14)

Checks if lhs is less than or equal to rhs .

Parameters

lhs, rhs - values to compare

Return value

lhs <= rhs .

If T is a pointer type, the result is consistent with the implementation-defined strict total order over pointers .

Exceptions

May throw implementation-defined exceptions.

Possible implementation

constexpr bool operator()(const T& lhs, const T& rhs) const 
{
    return lhs <= rhs; // assumes that the implementation handles pointer total order
}

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

See also

function object implementing x < y
(class template)
constrained function object implementing x <= y
(class)