C++ named requirements: MoveAssignable (since C++11) (original) (raw)
Specifies that an instance of the type can be assigned from an rvalue argument.
[edit] Requirements
The type T satisfies MoveAssignable if
Given
t, a modifiable lvalue expression of typeT,rv, an rvalue expression of typeT.
The following expressions must be valid and have their specified effects.
| Expression | Return type | Return value | Post-conditions |
|---|---|---|---|
| t = rv | T& | t | If t and rv do not refer to the same object, the value of t is equivalent to the value of rv before the assignment.The new value of rv is unspecified. |
[edit] Notes
The type does not have to implement move assignment operator in order to satisfy this type requirement: a copy assignment operator that takes its parameter by value or as a const Type&, will bind to rvalue argument.
If a MoveAssignable class implements a move assignment operator, it may also implement move semantics to take advantage of the fact that the value of rv after assignment is unspecified.