std::weak_equal (3) Linux Manual Page

std::weak_equal – std::weak_equal

Synopsis

Defined in header<compare>

    template <class T>
    (since C++ 20)

        constexpr std::weak_equality weak_equal(const T &a, const T &b);

Compares two values using 3-way comparison and produces a result of type std::weak_equality
Specifically,
* If the expression a <=> b is well-formed and its result is convertible to std::weak_equality, returns that result.
* Otherwise, if the expression a <=> b is well-formed, but its result is not convertible to std::weak_equality, then the function is defined as deleted.
* Otherwise, if the expression a <=> b is ill-formed, but the expression a == b is well-formed and convertible to bool,
      * if a == b is true, returns std::weak_equality::equivalent
      * otherwise, returns std::weak_equality::nonequivalent
* Otherwise, the function is defined as deleted.

Parameters

a, b – values to compare

Return value

A value of type std::weak_equality, as described above.

Notes

Example

 This section is incomplete
 Reason: no example

See also

weak_equality the result type of 3-way comparison that supports only equality/inequality and is not substitutable
              (class)
(C++20)
strong_equal performs 3-way comparison and produces a result of type std::strong_equality
              (function template)
(C++20)
strong_order performs 3-way comparison and produces a result of type std::strong_ordering
              (function template)
(C++20)
partial_order performs 3-way comparison and produces a result of type std::partial_ordering
              (function template)
(C++20)
weak_order performs 3-way comparison and produces a result of type std::weak_ordering
              (function template)
(C++20)