C++ named requirements: CopyConstructible

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C++ named requirements

Specifies that an instance of the type can be copy-constructed from an lvalue expression.


The type T satisfies CopyConstructible if


  • v, an lvalue expression of type T or const T or an rvalue expression of type const T
  • u, an arbitrary identifier

The following expressions must be valid and have their specified effects

Expression Post-conditions
T u = v; The value of u is equivalent to the value of v.

The value of v is unchanged

T(v) The value of T(v) is equivalent to the value of v.

The value of v is unchanged.

The expression v.~T() also must be valid, and, for lvalue v, the expression &v must have the type T* or const T* and must evaluate to the address of v

(until C++11)


Until C++11, classes that overloaded operator& were not CopyConstructible and thus weren't usable in the standard library containers. As of C++11, the standard library uses std::addressof whenever the address of an object is needed.

See also

checks if a type has a copy constructor
(class template)