cpp/named req/CopyConstructible

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

Requirements

The type T satisfies CopyConstructible if

• The type T satisfies Template:concept, and

Given

• 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)

Notes

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

is_copy_constructibleis_trivially_copy_constructibleis_nothrow_copy_constructible (C++11)(C++11)(C++11)

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