16 Library introduction [library]

16.4 Library-wide requirements [requirements]

16.4.4 Requirements on types and expressions [utility.requirements]

16.4.4.2 Template argument requirements [utility.arg.requirements]

Table 33 — Cpp17MoveAssignable requirements [tab:cpp17.moveassignable]
Expression
Return type
Return value
Post-condition
t = rv
T&
t
If t and rv do not refer to the same object, t is equivalent to the value of rv before the assignment
rv's state is unspecified.
[Note 2: 
rv must still meet the requirements of the library component that is using it, whether or not t and rv refer to the same object.
The operations listed in those requirements must work as specified whether rv has been moved from or not.
— end note]