+ ;; We must bind and close over INFO. Consider the case where we
+ ;; encapsulate (the second) an encapsulated (the first)
+ ;; definition, and later someone unencapsulates the encapsulated
+ ;; (first) definition. We don't want our encapsulation (second) to
+ ;; bind basic-definition to the encapsulated (first) definition
+ ;; when it no longer exists. When unencapsulating, we make sure to
+ ;; clobber the appropriate INFO structure to allow
+ ;; basic-definition to be bound to the next definition instead of
+ ;; an encapsulation that no longer exists.