std::less_equal<void>
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less_equal<>
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Defined in header
<functional>
template<>
class less_equal<void>;
(since C++14)
class less_equal<void>;
std::less_equal <void> is a specialization of std::less_equal with parameter and return type deduced.
Contents
[edit] Nested types
Nested type
Definition
is_transparent
unspecified
[edit] Member functions
operator()
(public member function)
std::less_equal<void>::operator()
template< class T, class U >
constexpr auto operator()( T&& lhs, U&& rhs ) const
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.
[edit] Exceptions
May throw implementation-defined exceptions.
[edit] Example
Run this code
#include <algorithm> #include <functional> #include <initializer_list> constexpr bool strictly_not_positive(int lhs) { return std::less_equal <>()(lhs, 0); } int main() { constexpr int low = 0, high = 8; std::less_equal <> less_equal{}; static_assert(less_equal(low, high)); static_assert(less_equal(low, low)); static constexpr auto arr = {1, 0, -1, -2, -3, -4}; static_assert(!std::all_of (arr.begin(), arr.end(), strictly_not_positive)); static_assert(std::all_of (arr.begin() + 1, arr.end(), strictly_not_positive)); }
[edit] 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 |