Specifies that an instance of the type can be assigned from an rvalue argument.
The following expressions must be valid and have their specified effects
| t = rv
| If |
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
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.