std::less_equal

 

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Template:ddcl list begin <tr class="t-dsc-header">

<td>

Defined in header <functional>

</td>

<td></td> <td></td> </tr> <tr class="t-dcl ">

<td class="t-dcl-nopad">

template< class T >
struct less_equal;

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<td class="t-dcl-nopad"> </td> <td class="t-dcl-nopad"> </td> </tr> Template:ddcl list end

Function object for performing comparisons. Implements operator<= on type T.

Notes

===Implementation-defined strict total order over pointers===

A specialization of std::less_equal for any pointer type yields the implementation-defined strict total order, even if the built-in operator<= operator does not.

The implementation-defined strict total order is consistent with the partial order imposed by built-in comparison operators (<=>,(since C++20)<, >, <=, and >=), and consistent among following standard function objects:

• std::less, std::greater, std::less_equal, and std::greater_equal, when the template argument is a pointer type or void(since C++14)

std::ranges::equal_to, std::ranges::not_equal_to, std::ranges::less, std::ranges::greater, std::ranges::less_equal, std::ranges::greater_equal, and std::compare_three_way

(since C++20)

Member types

type	definition
result_type	bool
first_argument_type	T
second_argument_type	T

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;

Checks if lhs is less than or equal to rhs.

Parameters

lhs, rhs

-

values to compare

Return value

true if lhs <= rhs, false otherwise.

Exceptions

(none)

Possible implementation

bool operator()(const T &lhs, const T &rhs) const { return lhs <= rhs; }