std::swappable, std::swappable_with
| Defined in header <concepts>
|
||
| template< class T > concept swappable = |
(1) | (since C++20) |
| template< class T, class U > concept swappable_with = |
(2) | (since C++20) |
The concept swappable<T> specifies that lvalues of type T are swappable.
The concept swappable_with<T, U> specifies that expressions of the type and value category encoded by T and U are swappable with each other. swappable_with<T, U> is satisfied only if a call to ranges::swap(t, u) exchanges the value of t and u, that is, given distinct objects t2 equal to t and u2 equal to u, after evaluating either ranges::swap(t, u) or ranges::swap(u, t), t2 is equal to u and u2 is equal to t.
Equality preservation
Expressions declared in requires expressions of the standard library concepts are required to be equality-preserving (except where stated otherwise).
References
- C++23 standard (ISO/IEC 14882:2024):
- 18.4.9 Concept
swappable[concept.swappable]
- 18.4.9 Concept
- C++20 standard (ISO/IEC 14882:2020):
- 18.4.9 Concept
swappable[concept.swappable]
- 18.4.9 Concept