std::copy_constructible
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copy_constructible
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Exposition-only concepts
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Defined in header
<concepts>
template< class T >
(since C++20)
concept copy_constructible =
std::move_constructible <T> &&
std::constructible_from <T, T&> && std::convertible_to <T&, T> &&
std::constructible_from <T, const T&> && std::convertible_to <const T&, T> &&
The concept copy_constructible is satisfied if T is an lvalue reference type, or if it is a move_constructible object type where an object of that type can constructed from a (possibly const) lvalue or const rvalue of that type in both direct- and copy-initialization contexts with the usual semantics (a copy is constructed with the source unchanged).
[edit] Semantic requirements
If T is an object type, then copy_constructible<T> is modeled only if given
- v, an lvalue of type (possibly const) T or an rvalue of type const T,
the following are true:
- After the definition T u = v;, u is equal to v and v is not modified;
- T(v) is equal to v and does not modify v.
[edit] References
- C++23 standard (ISO/IEC 14882:2024):
- 18.4.14 Concept
copy_constructible[concept.copyconstructible]
- 18.4.14 Concept
- C++20 standard (ISO/IEC 14882:2020):
- 18.4.14 Concept
copy_constructible[concept.copyconstructible]
- 18.4.14 Concept