wanted: (SETF %FUN-NAME) on closures, or %SET-CLOSURE-NAME

[Tobias C. Rittweiler]

%FUN-NAME does not work on slot accessors, predicates, copiers
created by means of DEFSTRUCT.

Using (SETF %FUN-NAME) when creating the defstruct slot-accessors,
predicates, copiers won't do because (SETF %FUN-NAME) modifies the
underlying function of a closure, and all these are closures
sharing the same underlying function.

;;; Test case for defstruct.impure.lisp

;;; If this is fixed, uncomment the FUNCTION-TYPE+DEFSTRUCT.N tests in
;;; the SB-INTROSPECT contrib.

(with-test (:name defstruct+%fun-name)
  (assert (eq (sb-kernel:%fun-name #'person-age) 'person-age))
  (assert (eq (sb-kernel:%fun-name #'copy-person) 'copy-person))
  (assert (eq (sb-kernel:%fun-name #'person-p) 'person-p))
  (assert (eq (sb-kernel:%fun-name #'astro-helmet-size) 'astro-helmet-size))
  (assert (eq (sb-kernel:%fun-name #'copy-astronaut) 'copy-astronaut)))

[Douglas Katzman (dougk)]

The implementation of defstruct accessors is different from what was described above - the predicate, copier, and accessors are genuine DEFUNs, not closures. As such, they have names.

Also, we have the ability to rename closures now (as of commit 111d187a4e82eb58f4013190ac330bc7c1efcc95), it operates in a way which may not meet users' expectations: naming a closure returns a new object.
So while I'm resolving this as "fixed", I don't think we should advertise named closures as a news item.