- ;; an indication of what we have proven about how this contination's
- ;; type assertion is satisfied:
- ;;
- ;; NIL
- ;; No type check is necessary (proven type is a subtype of the assertion.)
- ;;
- ;; T
- ;; A type check is needed.
- ;;
- ;; :DELETED
- ;; Don't do a type check, but believe (intersect) the assertion.
- ;; A T check can be changed to :DELETED if we somehow prove the
- ;; check is unnecessary, or if we eliminate it through a policy
- ;; decision.
- ;;
- ;; :NO-CHECK
- ;; Type check generation sets the slot to this if a check is
- ;; called for, but it believes it has proven that the check won't
- ;; be done for policy reasons or because a safe implementation
- ;; will be used. In the latter case, LTN must ensure that a safe
- ;; implementation *is* used.
- ;;
- ;; This is computed lazily by CONTINUATION-DERIVED-TYPE, so use
- ;; CONTINUATION-TYPE-CHECK instead of the %'ed slot accessor.
- (%type-check t :type (member t nil :deleted :no-check))
- ;; Asserted type, weakend according to policies
- (type-to-check *wild-type* :type ctype)