22 General utilities library [utilities]

22.5 Optional objects [optional]

22.5.3 Class template optional [optional.optional]

22.5.3.5 Swap [optional.swap]

Table 71 — optional​::​swap(optional&) effects [tab:optional.swap]
*this contains a value
*this does not contain a value
rhs contains a value
calls swap(val, rhs.val)
direct-non-list-initializes val with std​::​move(rhs.val), followed by rhs.val.T​::​~T(); postcondition is that *this contains a value and rhs does not contain a value
rhs does not contain a value
direct-non-list-initializes rhs.val with std​::​move(val), followed by val.T​::​~T(); postcondition is that *this does not contain a value and rhs contains a value
no effect