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Adjust the recent defmethod change.

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(compile-or-load-defgeneric name) doesn't need the full eval-when
repertoire, only :compile-toplevel and :execute. :compile-toplevel for
subsequent forms and :execute for references within the body of
defmethod to itself. :load-toplevel is not needed since when the FASLs
are loaded no further processing is performed, this avoids the size
increase of the resulting FASLs.
This commit is contained in:
Stas Boukarev 2013-11-02 17:39:50 +04:00
parent 8e6a4a018f
commit bd494c3bf5
1 changed files with 33 additions and 31 deletions
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64
src/pcl/boot.lisp
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@ -322,38 +322,40 @@ bootstrapping.
(multiple-value-bind (qualifiers lambda-list body)
(parse-defmethod args)
`(progn
(eval-when (:compile-toplevel :load-toplevel :execute)
(eval-when (:compile-toplevel :execute)
;; :compile-toplevel is needed for subsequent forms
;; :execute is needed for references to itself inside the body
(compile-or-load-defgeneric ',name))
;; KLUDGE: this double expansion is quite a monumental
;; workaround: it comes about because of a fantastic interaction
;; between the processing rules of CLHS 3.2.3.1 and the
;; bizarreness of MAKE-METHOD-LAMBDA.
;;
;; MAKE-METHOD-LAMBDA can be called by the user, and if the
;; lambda itself doesn't refer to outside bindings the return
;; value must be compileable in the null lexical environment.
;; However, the function must also refer somehow to the
;; associated method object, so that it can call NO-NEXT-METHOD
;; with the appropriate arguments if there is no next method --
;; but when the function is generated, the method object doesn't
;; exist yet.
;;
;; In order to resolve this issue, we insert a literal cons cell
;; into the body of the method lambda, return the same cons cell
;; as part of the second (initargs) return value of
;; MAKE-METHOD-LAMBDA, and a method on INITIALIZE-INSTANCE fills
;; in the cell when the method is created. However, this
;; strategy depends on having a fresh cons cell for every method
;; lambda, which (without the workaround below) is skewered by
;; the processing in CLHS 3.2.3.1, which permits implementations
;; to macroexpand the bodies of EVAL-WHEN forms with both
;; :COMPILE-TOPLEVEL and :LOAD-TOPLEVEL only once. The
;; expansion below forces the double expansion in those cases,
;; while expanding only once in the common case.
(eval-when (:load-toplevel)
(%defmethod-expander ,name ,qualifiers ,lambda-list ,body))
(eval-when (:execute)
(%defmethod-expander ,name ,qualifiers ,lambda-list ,body)))))
;; KLUDGE: this double expansion is quite a monumental
;; workaround: it comes about because of a fantastic interaction
;; between the processing rules of CLHS 3.2.3.1 and the
;; bizarreness of MAKE-METHOD-LAMBDA.
;;
;; MAKE-METHOD-LAMBDA can be called by the user, and if the
;; lambda itself doesn't refer to outside bindings the return
;; value must be compileable in the null lexical environment.
;; However, the function must also refer somehow to the
;; associated method object, so that it can call NO-NEXT-METHOD
;; with the appropriate arguments if there is no next method --
;; but when the function is generated, the method object doesn't
;; exist yet.
;;
;; In order to resolve this issue, we insert a literal cons cell
;; into the body of the method lambda, return the same cons cell
;; as part of the second (initargs) return value of
;; MAKE-METHOD-LAMBDA, and a method on INITIALIZE-INSTANCE fills
;; in the cell when the method is created. However, this
;; strategy depends on having a fresh cons cell for every method
;; lambda, which (without the workaround below) is skewered by
;; the processing in CLHS 3.2.3.1, which permits implementations
;; to macroexpand the bodies of EVAL-WHEN forms with both
;; :COMPILE-TOPLEVEL and :LOAD-TOPLEVEL only once. The
;; expansion below forces the double expansion in those cases,
;; while expanding only once in the common case.
(eval-when (:load-toplevel)
(%defmethod-expander ,name ,qualifiers ,lambda-list ,body))
(eval-when (:execute)
(%defmethod-expander ,name ,qualifiers ,lambda-list ,body)))))
(defmacro %defmethod-expander
(name qualifiers lambda-list body &environment env)