A completion that represents evaluation of a statement or an expression resulting in a return from a callable.
Holds if this completion will continue a loop when it is the completion of a loop body.
Gets the inner completion. This is either the inner completion, when the completion is nested, or the completion itself.
Gets the outer completion. This is either the outer completion, when the completion is nested, or the completion itself.
Holds if this completion is valid for control flow element