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std::move_constructible (since C++20)

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Defined in header <concepts>
template< class T >
concept move_constructible = std::constructible_from<T, T> && std::convertible_to<T, T>;
(since C++20)

The concept move_constructible is satisfied if T is a reference type, or if it is an object type where an object of that type can be constructed from an rvalue of that type in both direct- and copy-initialization contexts, with the usual semantics.

[edit] Semantic requirements

If T is an object type, then move_constructible<T> is modeled only if given

  • rv, an rvalue of type T, and
  • u2, a distinct object of type T equal to rv,

the following are true:

  • After the definition T u = rv;, u is equal to u2;
  • T(rv) is equal to u2; and
  • If T is not const-qualified, then rv's resulting state (after the definition/expression is evaluated in either bullets above) is valid but unspecified; otherwise, it is unchanged.

[edit] References

  • C++23 standard (ISO/IEC 14882:2024):
  • 18.4.13 Concept move_constructible [concept.moveconstructible]
  • C++20 standard (ISO/IEC 14882:2020):
  • 18.4.13 Concept move_constructible [concept.moveconstructible]

[edit] See also

checks if a type can be constructed from an rvalue reference
(class template) [edit]