1 ;;;; This software is part of the SBCL system. See the README file for
4 ;;;; This software is derived from software originally released by Xerox
5 ;;;; Corporation. Copyright and release statements follow. Later modifications
6 ;;;; to the software are in the public domain and are provided with
7 ;;;; absolutely no warranty. See the COPYING and CREDITS files for more
10 ;;;; copyright information from original PCL sources:
12 ;;;; Copyright (c) 1985, 1986, 1987, 1988, 1989, 1990 Xerox Corporation.
13 ;;;; All rights reserved.
15 ;;;; Use and copying of this software and preparation of derivative works based
16 ;;;; upon this software are permitted. Any distribution of this software or
17 ;;;; derivative works must comply with all applicable United States export
20 ;;;; This software is made available AS IS, and Xerox Corporation makes no
21 ;;;; warranty about the software, its performance or its conformity to any
26 (defmethod slot-accessor-function ((slotd effective-slot-definition) type)
28 (reader (slot-definition-reader-function slotd))
29 (writer (slot-definition-writer-function slotd))
30 (boundp (slot-definition-boundp-function slotd))))
32 (defmethod (setf slot-accessor-function) (function
33 (slotd effective-slot-definition)
36 (reader (setf (slot-definition-reader-function slotd) function))
37 (writer (setf (slot-definition-writer-function slotd) function))
38 (boundp (setf (slot-definition-boundp-function slotd) function))))
40 (defconstant +slotd-reader-function-std-p+ 1)
41 (defconstant +slotd-writer-function-std-p+ 2)
42 (defconstant +slotd-boundp-function-std-p+ 4)
43 (defconstant +slotd-all-function-std-p+ 7)
45 (defmethod slot-accessor-std-p ((slotd effective-slot-definition) type)
46 (let ((flags (slot-value slotd 'accessor-flags)))
47 (declare (type fixnum flags))
49 (eql +slotd-all-function-std-p+ flags)
50 (let ((mask (ecase type
51 (reader +slotd-reader-function-std-p+)
52 (writer +slotd-writer-function-std-p+)
53 (boundp +slotd-boundp-function-std-p+))))
54 (declare (type fixnum mask))
55 (not (zerop (the fixnum (logand mask flags))))))))
57 (defmethod (setf slot-accessor-std-p) (value
58 (slotd effective-slot-definition)
60 (let ((mask (ecase type
61 (reader +slotd-reader-function-std-p+)
62 (writer +slotd-writer-function-std-p+)
63 (boundp +slotd-boundp-function-std-p+)))
64 (flags (slot-value slotd 'accessor-flags)))
65 (declare (type fixnum mask flags))
66 (setf (slot-value slotd 'accessor-flags)
68 (the fixnum (logior mask flags))
69 (the fixnum (logand (the fixnum (lognot mask)) flags)))))
72 (defmethod initialize-internal-slot-functions ((slotd
73 effective-slot-definition))
74 (let* ((name (slot-value slotd 'name))
75 (class (slot-value slotd 'class)))
76 (let ((table (or (gethash name *name->class->slotd-table*)
77 (setf (gethash name *name->class->slotd-table*)
78 (make-hash-table :test 'eq :size 5)))))
79 (setf (gethash class table) slotd))
80 (dolist (type '(reader writer boundp))
81 (let* ((gf-name (ecase type
82 (reader 'slot-value-using-class)
83 (writer '(setf slot-value-using-class))
84 (boundp 'slot-boundp-using-class)))
85 (gf (gdefinition gf-name)))
86 (compute-slot-accessor-info slotd type gf)))
87 (initialize-internal-slot-gfs name)))
89 (defmethod compute-slot-accessor-info ((slotd effective-slot-definition)
91 (let* ((name (slot-value slotd 'name))
92 (class (slot-value slotd 'class))
93 (old-slotd (find-slot-definition class name))
94 (old-std-p (and old-slotd (slot-accessor-std-p old-slotd 'all))))
95 (multiple-value-bind (function std-p)
96 (if (eq *boot-state* 'complete)
97 (get-accessor-method-function gf type class slotd)
98 (get-optimized-std-accessor-method-function class slotd type))
99 (setf (slot-accessor-std-p slotd type) std-p)
100 (setf (slot-accessor-function slotd type) function))
101 (when (and old-slotd (not (eq old-std-p (slot-accessor-std-p slotd 'all))))
102 (push (cons class name) *pv-table-cache-update-info*))))
104 (defmethod slot-definition-allocation ((slotd structure-slot-definition))
107 (defmethod shared-initialize :after ((object documentation-mixin)
109 &key (documentation nil documentation-p))
110 (declare (ignore slot-names))
111 (when documentation-p
112 (setf (plist-value object 'documentation) documentation)))
114 ;;; default if DOC-TYPE doesn't match one of the specified types
115 (defmethod documentation (object doc-type)
116 (warn "unsupported DOCUMENTATION: type ~S for object ~S"
121 ;;; default if DOC-TYPE doesn't match one of the specified types
122 (defmethod (setf documentation) (new-value object doc-type)
123 ;; CMU CL made this an error, but since ANSI says that even for supported
124 ;; doc types an implementation is permitted to discard docs at any time
125 ;; for any reason, this feels to me more like a warning. -- WHN 19991214
126 (warn "discarding unsupported DOCUMENTATION of type ~S for object ~S"
131 (defmethod documentation ((object documentation-mixin) doc-type)
132 (declare (ignore doc-type))
133 (plist-value object 'documentation))
135 (defmethod (setf documentation) (new-value
136 (object documentation-mixin)
138 (declare (ignore doc-type))
139 (setf (plist-value object 'documentation) new-value))
141 (defmethod documentation ((slotd standard-slot-definition) doc-type)
142 (declare (ignore doc-type))
143 (slot-value slotd 'documentation))
145 (defmethod (setf documentation) (new-value
146 (slotd standard-slot-definition)
148 (declare (ignore doc-type))
149 (setf (slot-value slotd 'documentation) new-value))
151 ;;;; various class accessors that are a little more complicated than can be
152 ;;;; done with automatically generated reader methods
154 (defmethod class-finalized-p ((class pcl-class))
155 (with-slots (wrapper) class
156 (not (null wrapper))))
158 (defmethod class-prototype ((class std-class))
159 (with-slots (prototype) class
160 (or prototype (setq prototype (allocate-instance class)))))
162 (defmethod class-prototype ((class structure-class))
163 (with-slots (prototype wrapper defstruct-constructor) class
166 (if defstruct-constructor
167 (allocate-instance class)
168 (allocate-standard-instance wrapper))))))
170 (defmethod class-direct-default-initargs ((class slot-class))
171 (plist-value class 'direct-default-initargs))
173 (defmethod class-default-initargs ((class slot-class))
174 (plist-value class 'default-initargs))
176 (defmethod class-constructors ((class slot-class))
177 (plist-value class 'constructors))
179 (defmethod class-slot-cells ((class std-class))
180 (plist-value class 'class-slot-cells))
182 ;;;; class accessors that are even a little bit more complicated than those
183 ;;;; above. These have a protocol for updating them, we must implement that
186 ;;; Maintaining the direct subclasses backpointers. The update methods are
187 ;;; here, the values are read by an automatically generated reader method.
188 (defmethod add-direct-subclass ((class class) (subclass class))
189 (with-slots (direct-subclasses) class
190 (pushnew subclass direct-subclasses)
192 (defmethod remove-direct-subclass ((class class) (subclass class))
193 (with-slots (direct-subclasses) class
194 (setq direct-subclasses (remove subclass direct-subclasses))
197 ;;; Maintaining the direct-methods and direct-generic-functions backpointers.
199 ;;; There are four generic functions involved, each has one method for the
200 ;;; class case and another method for the damned EQL specializers. All of
201 ;;; these are specified methods and appear in their specified place in the
204 ;;; ADD-DIRECT-METHOD
205 ;;; REMOVE-DIRECT-METHOD
206 ;;; SPECIALIZER-DIRECT-METHODS
207 ;;; SPECIALIZER-DIRECT-GENERIC-FUNCTIONS
209 ;;; In each case, we maintain one value which is a cons. The car is the list
210 ;;; methods. The cdr is a list of the generic functions. The cdr is always
212 (defmethod add-direct-method ((specializer class) (method method))
213 (with-slots (direct-methods) specializer
214 (setf (car direct-methods) (adjoin method (car direct-methods)) ;PUSH
215 (cdr direct-methods) ()))
217 (defmethod remove-direct-method ((specializer class) (method method))
218 (with-slots (direct-methods) specializer
219 (setf (car direct-methods) (remove method (car direct-methods))
220 (cdr direct-methods) ()))
223 (defmethod specializer-direct-methods ((specializer class))
224 (with-slots (direct-methods) specializer
225 (car direct-methods)))
227 (defmethod specializer-direct-generic-functions ((specializer class))
228 (with-slots (direct-methods) specializer
229 (or (cdr direct-methods)
230 (setf (cdr direct-methods)
231 (gathering1 (collecting-once)
232 (dolist (m (car direct-methods))
233 (gather1 (method-generic-function m))))))))
235 ;;; This hash table is used to store the direct methods and direct generic
236 ;;; functions of EQL specializers. Each value in the table is the cons.
237 (defvar *eql-specializer-methods* (make-hash-table :test 'eql))
238 (defvar *class-eq-specializer-methods* (make-hash-table :test 'eq))
240 (defmethod specializer-method-table ((specializer eql-specializer))
241 *eql-specializer-methods*)
243 (defmethod specializer-method-table ((specializer class-eq-specializer))
244 *class-eq-specializer-methods*)
246 (defmethod add-direct-method ((specializer specializer-with-object) (method method))
247 (let* ((object (specializer-object specializer))
248 (table (specializer-method-table specializer))
249 (entry (gethash object table)))
252 (setf (gethash object table)
254 (setf (car entry) (adjoin method (car entry))
258 (defmethod remove-direct-method ((specializer specializer-with-object) (method method))
259 (let* ((object (specializer-object specializer))
260 (entry (gethash object (specializer-method-table specializer))))
262 (setf (car entry) (remove method (car entry))
266 (defmethod specializer-direct-methods ((specializer specializer-with-object))
267 (car (gethash (specializer-object specializer)
268 (specializer-method-table specializer))))
270 (defmethod specializer-direct-generic-functions ((specializer specializer-with-object))
271 (let* ((object (specializer-object specializer))
272 (entry (gethash object (specializer-method-table specializer))))
276 (gathering1 (collecting-once)
277 (dolist (m (car entry))
278 (gather1 (method-generic-function m)))))))))
280 (defun map-specializers (function)
281 (map-all-classes #'(lambda (class)
282 (funcall function (class-eq-specializer class))
283 (funcall function class)))
284 (maphash #'(lambda (object methods)
285 (declare (ignore methods))
286 (intern-eql-specializer object))
287 *eql-specializer-methods*)
288 (maphash #'(lambda (object specl)
289 (declare (ignore object))
290 (funcall function specl))
291 *eql-specializer-table*)
294 (defun map-all-generic-functions (function)
295 (let ((all-generic-functions (make-hash-table :test 'eq)))
296 (map-specializers #'(lambda (specl)
297 (dolist (gf (specializer-direct-generic-functions specl))
298 (unless (gethash gf all-generic-functions)
299 (setf (gethash gf all-generic-functions) t)
300 (funcall function gf))))))
303 (defmethod shared-initialize :after ((specl class-eq-specializer) slot-names &key)
304 (declare (ignore slot-names))
305 (setf (slot-value specl 'type) `(class-eq ,(specializer-class specl))))
307 (defmethod shared-initialize :after ((specl eql-specializer) slot-names &key)
308 (declare (ignore slot-names))
309 (setf (slot-value specl 'type) `(eql ,(specializer-object specl))))
311 (defun real-load-defclass (name metaclass-name supers slots other)
312 (let ((res (apply #'ensure-class name :metaclass metaclass-name
313 :direct-superclasses supers
315 :definition-source `((defclass ,name)
318 ;; Defclass of a class with a forward-referenced superclass does not
319 ;; have a wrapper. RES is the incomplete PCL class. The Lisp class
320 ;; does not yet exist. Maybe should return NIL in that case as RES
321 ;; is not useful to the user?
322 (and (class-wrapper res) (sb-kernel:layout-class (class-wrapper res)))))
324 (setf (gdefinition 'load-defclass) #'real-load-defclass)
326 (defun ensure-class (name &rest all)
327 (apply #'ensure-class-using-class name (find-class name nil) all))
329 (defmethod ensure-class-using-class (name (class null) &rest args &key)
330 (multiple-value-bind (meta initargs)
331 (ensure-class-values class args)
332 (inform-type-system-about-class (class-prototype meta) name);***
333 (setf class (apply #'make-instance meta :name name initargs)
334 (find-class name) class)
335 (inform-type-system-about-class class name) ;***
338 (defmethod ensure-class-using-class (name (class pcl-class) &rest args &key)
339 (multiple-value-bind (meta initargs)
340 (ensure-class-values class args)
341 (unless (eq (class-of class) meta) (change-class class meta))
342 (apply #'reinitialize-instance class initargs)
343 (setf (find-class name) class)
344 (inform-type-system-about-class class name) ;***
347 (defmethod class-predicate-name ((class t))
350 (defun ensure-class-values (class args)
351 (let* ((initargs (copy-list args))
352 (unsupplied (list 1))
353 (supplied-meta (getf initargs :metaclass unsupplied))
354 (supplied-supers (getf initargs :direct-superclasses unsupplied))
355 (supplied-slots (getf initargs :direct-slots unsupplied))
357 (cond ((neq supplied-meta unsupplied)
358 (find-class supplied-meta))
360 (forward-referenced-class-p class))
361 *the-class-standard-class*)
364 (flet ((fix-super (s)
366 ((not (legal-class-name-p s))
367 (error "~S is not a class or a legal class name." s))
369 (or (find-class s nil)
371 (make-instance 'forward-referenced-class
373 (loop (unless (remf initargs :metaclass) (return)))
374 (loop (unless (remf initargs :direct-superclasses) (return)))
375 (loop (unless (remf initargs :direct-slots) (return)))
377 (list* :direct-superclasses
378 (and (neq supplied-supers unsupplied)
379 (mapcar #'fix-super supplied-supers))
381 (and (neq supplied-slots unsupplied) supplied-slots)
384 #|| ; since it doesn't do anything
385 (defmethod shared-initialize :before ((class std-class)
387 &key direct-superclasses)
388 (declare (ignore slot-names))
389 ;; *** error checking
393 (defmethod shared-initialize :after
396 &key (direct-superclasses nil direct-superclasses-p)
397 (direct-slots nil direct-slots-p)
398 (direct-default-initargs nil direct-default-initargs-p)
399 (predicate-name nil predicate-name-p))
400 (declare (ignore slot-names))
401 (cond (direct-superclasses-p
402 (setq direct-superclasses
403 (or direct-superclasses
404 (list (if (funcallable-standard-class-p class)
405 *the-class-funcallable-standard-object*
406 *the-class-standard-object*))))
407 (dolist (superclass direct-superclasses)
408 (unless (validate-superclass class superclass)
409 (error "The class ~S was specified as a~%
410 super-class of the class ~S;~%~
411 but the meta-classes ~S and~%~S are incompatible.~@
412 Define a method for ~S to avoid this error."
413 superclass class (class-of superclass) (class-of class)
414 'validate-superclass)))
415 (setf (slot-value class 'direct-superclasses) direct-superclasses))
417 (setq direct-superclasses (slot-value class 'direct-superclasses))))
420 (setf (slot-value class 'direct-slots)
421 (mapcar #'(lambda (pl) (make-direct-slotd class pl)) direct-slots))
422 (slot-value class 'direct-slots)))
423 (if direct-default-initargs-p
424 (setf (plist-value class 'direct-default-initargs) direct-default-initargs)
425 (setq direct-default-initargs (plist-value class 'direct-default-initargs)))
426 (setf (plist-value class 'class-slot-cells)
427 (gathering1 (collecting)
428 (dolist (dslotd direct-slots)
429 (when (eq (slot-definition-allocation dslotd) class)
430 (let ((initfunction (slot-definition-initfunction dslotd)))
431 (gather1 (cons (slot-definition-name dslotd)
433 (funcall initfunction)
434 +slot-unbound+))))))))
435 (setq predicate-name (if predicate-name-p
436 (setf (slot-value class 'predicate-name)
437 (car predicate-name))
438 (or (slot-value class 'predicate-name)
439 (setf (slot-value class 'predicate-name)
440 (make-class-predicate-name (class-name class))))))
441 (add-direct-subclasses class direct-superclasses)
442 (update-class class nil)
443 (make-class-predicate class predicate-name)
444 (add-slot-accessors class direct-slots))
446 (defmethod shared-initialize :before ((class class) slot-names &key name)
447 (declare (ignore slot-names name))
448 ;; FIXME: Could this just be CLASS instead of `(CLASS ,CLASS)? If not,
449 ;; why not? (See also similar expression in !BOOTSTRAP-INITIALIZE-CLASS.)
450 (setf (slot-value class 'type) `(class ,class))
451 (setf (slot-value class 'class-eq-specializer)
452 (make-instance 'class-eq-specializer :class class)))
454 (defmethod reinitialize-instance :before ((class slot-class) &key)
455 (remove-direct-subclasses class (class-direct-superclasses class))
456 (remove-slot-accessors class (class-direct-slots class)))
458 (defmethod reinitialize-instance :after ((class slot-class)
461 (map-dependents class
462 #'(lambda (dependent)
463 (apply #'update-dependent class dependent initargs))))
465 (defmethod shared-initialize :after
466 ((class structure-class)
468 &key (direct-superclasses nil direct-superclasses-p)
469 (direct-slots nil direct-slots-p)
470 direct-default-initargs
471 (predicate-name nil predicate-name-p))
472 (declare (ignore slot-names direct-default-initargs))
473 (if direct-superclasses-p
474 (setf (slot-value class 'direct-superclasses)
475 (or direct-superclasses
476 (setq direct-superclasses
477 (and (not (eq (class-name class) 'structure-object))
478 (list *the-class-structure-object*)))))
479 (setq direct-superclasses (slot-value class 'direct-superclasses)))
480 (let* ((name (class-name class))
481 (from-defclass-p (slot-value class 'from-defclass-p))
482 (defstruct-p (or from-defclass-p (not (structure-type-p name)))))
484 (setf (slot-value class 'direct-slots)
486 (mapcar #'(lambda (pl)
488 (let* ((slot-name (getf pl :name))
489 (acc-name (format nil "~S structure class ~A"
491 (accessor (intern acc-name)))
492 (setq pl (list* :defstruct-accessor-symbol accessor
494 (make-direct-slotd class pl))
496 (setq direct-slots (slot-value class 'direct-slots)))
498 (let* ((include (car (slot-value class 'direct-superclasses)))
499 (conc-name (intern (format nil "~S structure class " name)))
500 (constructor (intern (format nil "~A constructor" conc-name)))
501 (defstruct `(defstruct (,name
503 `((:include ,(class-name include))))
504 (:print-function print-std-instance)
506 (:conc-name ,conc-name)
507 (:constructor ,constructor ()))
508 ,@(mapcar #'(lambda (slot)
509 `(,(slot-definition-name slot)
512 (reader-names (mapcar (lambda (slotd)
516 (slot-definition-name
519 (writer-names (mapcar (lambda (slotd)
523 (slot-definition-name
527 (mapcar (lambda (slotd reader-name)
529 (slot-definition-defstruct-accessor-symbol
531 `(defun ,reader-name (obj)
532 (declare (type ,name obj))
534 direct-slots reader-names))
536 (mapcar (lambda (slotd writer-name)
538 (slot-definition-defstruct-accessor-symbol
540 `(defun ,writer-name (nv obj)
541 (declare (type ,name obj))
542 (setf (,accessor obj) nv))))
543 direct-slots writer-names))
547 ,@readers-init ,@writers-init
549 (unless (structure-type-p name) (eval defstruct-form))
550 (mapc #'(lambda (dslotd reader-name writer-name)
551 (let* ((reader (gdefinition reader-name))
552 (writer (when (gboundp writer-name)
553 (gdefinition writer-name))))
554 (setf (slot-value dslotd 'internal-reader-function)
556 (setf (slot-value dslotd 'internal-writer-function)
558 direct-slots reader-names writer-names)
559 (setf (slot-value class 'defstruct-form) defstruct-form)
560 (setf (slot-value class 'defstruct-constructor) constructor))))
561 (add-direct-subclasses class direct-superclasses)
562 (setf (slot-value class 'class-precedence-list)
563 (compute-class-precedence-list class))
564 (setf (slot-value class 'slots) (compute-slots class))
565 (let ((lclass (cl:find-class (class-name class))))
566 (setf (sb-kernel:class-pcl-class lclass) class)
567 (setf (slot-value class 'wrapper) (sb-kernel:class-layout lclass)))
568 (update-pv-table-cache-info class)
569 (setq predicate-name (if predicate-name-p
570 (setf (slot-value class 'predicate-name)
571 (car predicate-name))
572 (or (slot-value class 'predicate-name)
573 (setf (slot-value class 'predicate-name)
574 (make-class-predicate-name (class-name class))))))
575 (make-class-predicate class predicate-name)
576 (add-slot-accessors class direct-slots))
578 (defmethod direct-slot-definition-class ((class structure-class) initargs)
579 (declare (ignore initargs))
580 (find-class 'structure-direct-slot-definition))
582 (defmethod finalize-inheritance ((class structure-class))
583 nil) ; always finalized
585 (defun add-slot-accessors (class dslotds)
586 (fix-slot-accessors class dslotds 'add))
588 (defun remove-slot-accessors (class dslotds)
589 (fix-slot-accessors class dslotds 'remove))
591 (defun fix-slot-accessors (class dslotds add/remove)
592 (flet ((fix (gfspec name r/w)
593 (let ((gf (ensure-generic-function gfspec)))
595 (r (if (eq add/remove 'add)
596 (add-reader-method class gf name)
597 (remove-reader-method class gf)))
598 (w (if (eq add/remove 'add)
599 (add-writer-method class gf name)
600 (remove-writer-method class gf)))))))
601 (dolist (dslotd dslotds)
602 (let ((slot-name (slot-definition-name dslotd)))
603 (dolist (r (slot-definition-readers dslotd)) (fix r slot-name 'r))
604 (dolist (w (slot-definition-writers dslotd)) (fix w slot-name 'w))))))
606 (defun add-direct-subclasses (class new)
608 (unless (memq class (class-direct-subclasses class))
609 (add-direct-subclass n class))))
611 (defun remove-direct-subclasses (class new)
612 (let ((old (class-direct-superclasses class)))
613 (dolist (o (set-difference old new))
614 (remove-direct-subclass o class))))
616 (defmethod finalize-inheritance ((class std-class))
617 (update-class class t))
619 (defun class-has-a-forward-referenced-superclass-p (class)
620 (or (forward-referenced-class-p class)
621 (some #'class-has-a-forward-referenced-superclass-p
622 (class-direct-superclasses class))))
624 ;;; This is called by :after shared-initialize whenever a class is initialized
625 ;;; or reinitialized. The class may or may not be finalized.
626 (defun update-class (class finalizep)
627 (when (or finalizep (class-finalized-p class)
628 (not (class-has-a-forward-referenced-superclass-p class)))
629 (update-cpl class (compute-class-precedence-list class))
630 (update-slots class (compute-slots class))
631 (update-gfs-of-class class)
632 (update-inits class (compute-default-initargs class))
633 (update-make-instance-function-table class))
635 (dolist (sub (class-direct-subclasses class)) (update-class sub nil))))
637 (defun update-cpl (class cpl)
638 (if (class-finalized-p class)
639 (unless (equal (class-precedence-list class) cpl)
640 ;; comment from the old CMU CL sources:
641 ;; Need to have the cpl setup before update-lisp-class-layout
642 ;; is called on CMU CL.
643 (setf (slot-value class 'class-precedence-list) cpl)
644 (force-cache-flushes class))
645 (setf (slot-value class 'class-precedence-list) cpl))
646 (update-class-can-precede-p cpl))
648 (defun update-class-can-precede-p (cpl)
650 (let ((first (car cpl)))
651 (dolist (c (cdr cpl))
652 (pushnew c (slot-value first 'can-precede-list))))
653 (update-class-can-precede-p (cdr cpl))))
655 (defun class-can-precede-p (class1 class2)
656 (member class2 (class-can-precede-list class1)))
658 (defun update-slots (class eslotds)
659 (let ((instance-slots ())
661 (dolist (eslotd eslotds)
662 (let ((alloc (slot-definition-allocation eslotd)))
663 (cond ((eq alloc :instance) (push eslotd instance-slots))
664 ((classp alloc) (push eslotd class-slots)))))
666 ;; If there is a change in the shape of the instances then the
667 ;; old class is now obsolete.
668 (let* ((nlayout (mapcar #'slot-definition-name
669 (sort instance-slots #'< :key #'slot-definition-location)))
670 (nslots (length nlayout))
671 (nwrapper-class-slots (compute-class-slots class-slots))
672 (owrapper (class-wrapper class))
673 (olayout (and owrapper (wrapper-instance-slots-layout owrapper)))
674 (owrapper-class-slots (and owrapper (wrapper-class-slots owrapper)))
676 (cond ((null owrapper)
677 (make-wrapper nslots class))
678 ((and (equal nlayout olayout)
680 (iterate ((o (list-elements owrapper-class-slots))
681 (n (list-elements nwrapper-class-slots)))
682 (unless (eq (car o) (car n)) (return t)))))
685 ;; This will initialize the new wrapper to have the same
686 ;; state as the old wrapper. We will then have to change
687 ;; that. This may seem like wasted work (it is), but the
688 ;; spec requires that we call make-instances-obsolete.
689 (make-instances-obsolete class)
690 (class-wrapper class)))))
692 (with-slots (wrapper slots) class
693 (update-lisp-class-layout class nwrapper)
695 (wrapper-instance-slots-layout nwrapper) nlayout
696 (wrapper-class-slots nwrapper) nwrapper-class-slots
697 (wrapper-no-of-instance-slots nwrapper) nslots
700 (unless (eq owrapper nwrapper)
701 (update-pv-table-cache-info class)))))
703 (defun compute-class-slots (eslotds)
704 (gathering1 (collecting)
705 (dolist (eslotd eslotds)
707 (assoc (slot-definition-name eslotd)
708 (class-slot-cells (slot-definition-allocation eslotd)))))))
710 (defun compute-layout (cpl instance-eslotds)
712 (gathering1 (collecting)
713 (dolist (eslotd instance-eslotds)
714 (when (eq (slot-definition-allocation eslotd) :instance)
715 (gather1 (slot-definition-name eslotd))))))
717 (labels ((rwalk (tail)
720 (dolist (ss (class-slots (car tail)))
721 (let ((n (slot-definition-name ss)))
722 (when (member n names)
723 (setq order (cons n order)
724 names (remove n names))))))))
725 (rwalk (if (slot-boundp (car cpl) 'slots)
728 (reverse (append names order)))))
730 (defun update-gfs-of-class (class)
731 (when (and (class-finalized-p class)
732 (let ((cpl (class-precedence-list class)))
733 (or (member *the-class-slot-class* cpl)
734 (member *the-class-standard-effective-slot-definition* cpl))))
735 (let ((gf-table (make-hash-table :test 'eq)))
736 (labels ((collect-gfs (class)
737 (dolist (gf (specializer-direct-generic-functions class))
738 (setf (gethash gf gf-table) t))
739 (mapc #'collect-gfs (class-direct-superclasses class))))
741 (maphash #'(lambda (gf ignore)
742 (declare (ignore ignore))
743 (update-gf-dfun class gf))
746 (defun update-inits (class inits)
747 (setf (plist-value class 'default-initargs) inits))
749 (defmethod compute-default-initargs ((class slot-class))
750 (let ((cpl (class-precedence-list class))
751 (direct (class-direct-default-initargs class)))
752 (labels ((walk (tail)
755 (let ((c (pop tail)))
756 (append (if (eq c class)
758 (class-direct-default-initargs c))
760 (let ((initargs (walk cpl)))
761 (delete-duplicates initargs :test #'eq :key #'car :from-end t)))))
763 ;;;; protocols for constructing direct and effective slot definitions
765 (defmethod direct-slot-definition-class ((class std-class) initargs)
766 (declare (ignore initargs))
767 (find-class 'standard-direct-slot-definition))
769 (defun make-direct-slotd (class initargs)
770 (let ((initargs (list* :class class initargs)))
771 (apply #'make-instance
772 (direct-slot-definition-class class initargs)
775 (defmethod compute-slots ((class std-class))
776 ;; As specified, we must call COMPUTE-EFFECTIVE-SLOT-DEFINITION once
777 ;; for each different slot name we find in our superclasses. Each
778 ;; call receives the class and a list of the dslotds with that name.
779 ;; The list is in most-specific-first order.
780 (let ((name-dslotds-alist ()))
781 (dolist (c (class-precedence-list class))
782 (let ((dslotds (class-direct-slots c)))
784 (let* ((name (slot-definition-name d))
785 (entry (assq name name-dslotds-alist)))
788 (push (list name d) name-dslotds-alist))))))
789 (mapcar #'(lambda (direct)
790 (compute-effective-slot-definition class
791 (nreverse (cdr direct))))
792 name-dslotds-alist)))
794 (defmethod compute-slots :around ((class std-class))
795 (let ((eslotds (call-next-method))
796 (cpl (class-precedence-list class))
799 (dolist (eslotd eslotds)
800 (let ((alloc (slot-definition-allocation eslotd)))
801 (cond ((eq alloc :instance) (push eslotd instance-slots))
802 ((classp alloc) (push eslotd class-slots)))))
803 (let ((nlayout (compute-layout cpl instance-slots)))
804 (dolist (eslotd instance-slots)
805 (setf (slot-definition-location eslotd)
806 (position (slot-definition-name eslotd) nlayout))))
807 (dolist (eslotd class-slots)
808 (setf (slot-definition-location eslotd)
809 (assoc (slot-definition-name eslotd)
810 (class-slot-cells (slot-definition-allocation eslotd)))))
811 (mapc #'initialize-internal-slot-functions eslotds)
814 (defmethod compute-slots ((class structure-class))
815 (mapcan #'(lambda (superclass)
816 (mapcar #'(lambda (dslotd)
817 (compute-effective-slot-definition class
819 (class-direct-slots superclass)))
820 (reverse (slot-value class 'class-precedence-list))))
822 (defmethod compute-slots :around ((class structure-class))
823 (let ((eslotds (call-next-method)))
824 (mapc #'initialize-internal-slot-functions eslotds)
827 (defmethod compute-effective-slot-definition ((class slot-class) dslotds)
828 (let* ((initargs (compute-effective-slot-definition-initargs class dslotds))
829 (class (effective-slot-definition-class class initargs)))
830 (apply #'make-instance class initargs)))
832 (defmethod effective-slot-definition-class ((class std-class) initargs)
833 (declare (ignore initargs))
834 (find-class 'standard-effective-slot-definition))
836 (defmethod effective-slot-definition-class ((class structure-class) initargs)
837 (declare (ignore initargs))
838 (find-class 'structure-effective-slot-definition))
840 (defmethod compute-effective-slot-definition-initargs
841 ((class slot-class) direct-slotds)
852 (dolist (slotd direct-slotds)
855 (setq name (slot-definition-name slotd)
858 (when (slot-definition-initfunction slotd)
859 (setq initform (slot-definition-initform slotd)
860 initfunction (slot-definition-initfunction slotd)
863 (setq allocation (slot-definition-allocation slotd)
865 (setq initargs (append (slot-definition-initargs slotd) initargs))
866 (let ((slotd-type (slot-definition-type slotd)))
867 (setq type (cond ((eq type 't) slotd-type)
868 ((*subtypep type slotd-type) type)
869 (t `(and ,type ,slotd-type)))))))
872 :initfunction initfunction
874 :allocation allocation
878 (defmethod compute-effective-slot-definition-initargs :around
879 ((class structure-class) direct-slotds)
880 (let ((slotd (car direct-slotds)))
881 (list* :defstruct-accessor-symbol (slot-definition-defstruct-accessor-symbol slotd)
882 :internal-reader-function (slot-definition-internal-reader-function slotd)
883 :internal-writer-function (slot-definition-internal-writer-function slotd)
884 (call-next-method))))
886 ;;; NOTE: For bootstrapping considerations, these can't use make-instance
887 ;;; to make the method object. They have to use make-a-method which
888 ;;; is a specially bootstrapped mechanism for making standard methods.
889 (defmethod reader-method-class ((class slot-class) direct-slot &rest initargs)
890 (declare (ignore direct-slot initargs))
891 (find-class 'standard-reader-method))
893 (defmethod add-reader-method ((class slot-class) generic-function slot-name)
894 (add-method generic-function
895 (make-a-method 'standard-reader-method
897 (list (or (class-name class) 'object))
899 (make-reader-method-function class slot-name)
900 "automatically generated reader method"
903 (defmethod writer-method-class ((class slot-class) direct-slot &rest initargs)
904 (declare (ignore direct-slot initargs))
905 (find-class 'standard-writer-method))
907 (defmethod add-writer-method ((class slot-class) generic-function slot-name)
908 (add-method generic-function
909 (make-a-method 'standard-writer-method
911 (list 'new-value (or (class-name class) 'object))
912 (list *the-class-t* class)
913 (make-writer-method-function class slot-name)
914 "automatically generated writer method"
917 (defmethod add-boundp-method ((class slot-class) generic-function slot-name)
918 (add-method generic-function
919 (make-a-method 'standard-boundp-method
921 (list (or (class-name class) 'object))
923 (make-boundp-method-function class slot-name)
924 "automatically generated boundp method"
927 (defmethod remove-reader-method ((class slot-class) generic-function)
928 (let ((method (get-method generic-function () (list class) nil)))
929 (when method (remove-method generic-function method))))
931 (defmethod remove-writer-method ((class slot-class) generic-function)
933 (get-method generic-function () (list *the-class-t* class) nil)))
934 (when method (remove-method generic-function method))))
936 (defmethod remove-boundp-method ((class slot-class) generic-function)
937 (let ((method (get-method generic-function () (list class) nil)))
938 (when method (remove-method generic-function method))))
940 ;;; make-reader-method-function and make-write-method function are NOT part of
941 ;;; the standard protocol. They are however useful, PCL makes uses makes use
942 ;;; of them internally and documents them for PCL users.
944 ;;; *** This needs work to make type testing by the writer functions which
945 ;;; *** do type testing faster. The idea would be to have one constructor
946 ;;; *** for each possible type test. In order to do this it would be nice
947 ;;; *** to have help from inform-type-system-about-class and friends.
949 ;;; *** There is a subtle bug here which is going to have to be fixed.
950 ;;; *** Namely, the simplistic use of the template has to be fixed. We
951 ;;; *** have to give the optimize-slot-value method the user might have
952 ;;; *** defined for this metclass a chance to run.
954 (defmethod make-reader-method-function ((class slot-class) slot-name)
955 (make-std-reader-method-function (class-name class) slot-name))
957 (defmethod make-writer-method-function ((class slot-class) slot-name)
958 (make-std-writer-method-function (class-name class) slot-name))
960 (defmethod make-boundp-method-function ((class slot-class) slot-name)
961 (make-std-boundp-method-function (class-name class) slot-name))
963 ;;;; inform-type-system-about-class
964 ;;;; make-type-predicate
966 ;;; These are NOT part of the standard protocol. They are internal mechanism
967 ;;; which PCL uses to *try* and tell the type system about class definitions.
968 ;;; In a more fully integrated implementation of CLOS, the type system would
969 ;;; know about class objects and class names in a more fundamental way and
970 ;;; the mechanism used to inform the type system about new classes would be
972 (defmethod inform-type-system-about-class ((class std-class) name)
973 (inform-type-system-about-std-class name))
975 (defmethod compatible-meta-class-change-p (class proto-new-class)
976 (eq (class-of class) (class-of proto-new-class)))
978 (defmethod validate-superclass ((class class) (new-super class))
979 (or (eq new-super *the-class-t*)
980 (eq (class-of class) (class-of new-super))))
982 (defmethod validate-superclass ((class standard-class) (new-super std-class))
983 (let ((new-super-meta-class (class-of new-super)))
984 (or (eq new-super-meta-class *the-class-std-class*)
985 (eq (class-of class) new-super-meta-class))))
987 (defun force-cache-flushes (class)
988 (let* ((owrapper (class-wrapper class))
989 (state (wrapper-state owrapper)))
990 ;; We only need to do something if the state is still T. If the
991 ;; state isn't T, it will be FLUSH or OBSOLETE, and both of those
992 ;; will already be doing what we want. In particular, we must be
993 ;; sure we never change an OBSOLETE into a FLUSH since OBSOLETE
994 ;; means do what FLUSH does and then some.
995 (when (eq state 't) ; FIXME: should be done through INVALID-WRAPPER-P
996 (let ((nwrapper (make-wrapper (wrapper-no-of-instance-slots owrapper)
998 (setf (wrapper-instance-slots-layout nwrapper)
999 (wrapper-instance-slots-layout owrapper))
1000 (setf (wrapper-class-slots nwrapper)
1001 (wrapper-class-slots owrapper))
1002 (sb-sys:without-interrupts
1003 (update-lisp-class-layout class nwrapper)
1004 (setf (slot-value class 'wrapper) nwrapper)
1005 (invalidate-wrapper owrapper ':flush nwrapper))))))
1007 (defun flush-cache-trap (owrapper nwrapper instance)
1008 (declare (ignore owrapper))
1009 (set-wrapper instance nwrapper))
1011 ;;; make-instances-obsolete can be called by user code. It will cause the
1012 ;;; next access to the instance (as defined in 88-002R) to trap through the
1013 ;;; update-instance-for-redefined-class mechanism.
1014 (defmethod make-instances-obsolete ((class std-class))
1015 (let* ((owrapper (class-wrapper class))
1016 (nwrapper (make-wrapper (wrapper-no-of-instance-slots owrapper)
1018 (setf (wrapper-instance-slots-layout nwrapper)
1019 (wrapper-instance-slots-layout owrapper))
1020 (setf (wrapper-class-slots nwrapper)
1021 (wrapper-class-slots owrapper))
1022 (sb-sys:without-interrupts
1023 (update-lisp-class-layout class nwrapper)
1024 (setf (slot-value class 'wrapper) nwrapper)
1025 (invalidate-wrapper owrapper ':obsolete nwrapper)
1028 (defmethod make-instances-obsolete ((class symbol))
1029 (make-instances-obsolete (find-class class)))
1031 ;;; obsolete-instance-trap is the internal trap that is called when we see
1032 ;;; an obsolete instance. The times when it is called are:
1033 ;;; - when the instance is involved in method lookup
1034 ;;; - when attempting to access a slot of an instance
1036 ;;; It is not called by class-of, wrapper-of, or any of the low-level instance
1039 ;;; Of course these times when it is called are an internal implementation
1040 ;;; detail of PCL and are not part of the documented description of when the
1041 ;;; obsolete instance update happens. The documented description is as it
1042 ;;; appears in 88-002R.
1044 ;;; This has to return the new wrapper, so it counts on all the methods on
1045 ;;; obsolete-instance-trap-internal to return the new wrapper. It also does
1046 ;;; a little internal error checking to make sure that the traps are only
1047 ;;; happening when they should, and that the trap methods are computing
1048 ;;; appropriate new wrappers.
1050 ;;; obsolete-instance-trap might be called on structure instances
1051 ;;; after a structure is redefined. In most cases, obsolete-instance-trap
1052 ;;; will not be able to fix the old instance, so it must signal an
1053 ;;; error. The hard part of this is that the error system and debugger
1054 ;;; might cause obsolete-instance-trap to be called again, so in that
1055 ;;; case, we have to return some reasonable wrapper, instead.
1057 (defvar *in-obsolete-instance-trap* nil)
1058 (defvar *the-wrapper-of-structure-object*
1059 (class-wrapper (find-class 'structure-object)))
1061 (define-condition obsolete-structure (error)
1062 ((datum :reader obsolete-structure-datum :initarg :datum))
1064 (lambda (condition stream)
1065 ;; Don't try to print the structure, since it probably won't work.
1067 "obsolete structure error in ~S:~@
1068 for a structure of type: ~S"
1069 (sb-kernel::condition-function-name condition)
1070 (type-of (obsolete-structure-datum condition))))))
1072 (defun obsolete-instance-trap (owrapper nwrapper instance)
1073 (if (not (pcl-instance-p instance))
1074 (if *in-obsolete-instance-trap*
1075 *the-wrapper-of-structure-object*
1076 (let ((*in-obsolete-instance-trap* t))
1077 (error 'obsolete-structure :datum instance)))
1078 (let* ((class (wrapper-class* nwrapper))
1079 (copy (allocate-instance class)) ;??? allocate-instance ???
1080 (olayout (wrapper-instance-slots-layout owrapper))
1081 (nlayout (wrapper-instance-slots-layout nwrapper))
1082 (oslots (get-slots instance))
1083 (nslots (get-slots copy))
1084 (oclass-slots (wrapper-class-slots owrapper))
1088 ;; local --> local transfer
1089 ;; local --> shared discard
1090 ;; local --> -- discard
1091 ;; shared --> local transfer
1092 ;; shared --> shared discard
1093 ;; shared --> -- discard
1097 ;; Go through all the old local slots.
1098 (iterate ((name (list-elements olayout))
1099 (opos (interval :from 0)))
1100 (let ((npos (posq name nlayout)))
1102 (setf (instance-ref nslots npos) (instance-ref oslots opos))
1104 (push name discarded)
1105 (unless (eq (instance-ref oslots opos) +slot-unbound+)
1106 (setf (getf plist name) (instance-ref oslots opos)))))))
1108 ;; Go through all the old shared slots.
1109 (iterate ((oclass-slot-and-val (list-elements oclass-slots)))
1110 (let ((name (car oclass-slot-and-val))
1111 (val (cdr oclass-slot-and-val)))
1112 (let ((npos (posq name nlayout)))
1114 (setf (instance-ref nslots npos) (cdr oclass-slot-and-val))
1115 (progn (push name discarded)
1116 (unless (eq val +slot-unbound+)
1117 (setf (getf plist name) val)))))))
1119 ;; Go through all the new local slots to compute the added slots.
1120 (dolist (nlocal nlayout)
1121 (unless (or (memq nlocal olayout)
1122 (assq nlocal oclass-slots))
1123 (push nlocal added)))
1125 (swap-wrappers-and-slots instance copy)
1127 (update-instance-for-redefined-class instance
1133 (defmacro copy-instance-internal (instance)
1135 (let* ((class (class-of instance))
1136 (copy (allocate-instance class)))
1137 (if (std-instance-p ,instance)
1138 (setf (std-instance-slots ,instance)
1139 (std-instance-slots ,instance))
1140 (setf (fsc-instance-slots ,instance)
1141 (fsc-instance-slots ,instance)))
1144 (defun change-class-internal (instance new-class)
1145 (let* ((old-class (class-of instance))
1146 (copy (allocate-instance new-class))
1147 (new-wrapper (get-wrapper copy))
1148 (old-wrapper (class-wrapper old-class))
1149 (old-layout (wrapper-instance-slots-layout old-wrapper))
1150 (new-layout (wrapper-instance-slots-layout new-wrapper))
1151 (old-slots (get-slots instance))
1152 (new-slots (get-slots copy))
1153 (old-class-slots (wrapper-class-slots old-wrapper)))
1155 ;; "The values of local slots specified by both the class CTO and
1156 ;; CFROM are retained. If such a local slot was unbound, it remains
1158 (iterate ((new-slot (list-elements new-layout))
1159 (new-position (interval :from 0)))
1160 (let ((old-position (posq new-slot old-layout)))
1162 (setf (instance-ref new-slots new-position)
1163 (instance-ref old-slots old-position)))))
1165 ;; "The values of slots specified as shared in the class CFROM and
1166 ;; as local in the class CTO are retained."
1167 (iterate ((slot-and-val (list-elements old-class-slots)))
1168 (let ((position (posq (car slot-and-val) new-layout)))
1170 (setf (instance-ref new-slots position) (cdr slot-and-val)))))
1172 ;; Make the copy point to the old instance's storage, and make the
1173 ;; old instance point to the new storage.
1174 (swap-wrappers-and-slots instance copy)
1176 (update-instance-for-different-class copy instance)
1179 (defmethod change-class ((instance standard-object)
1180 (new-class standard-class))
1181 (change-class-internal instance new-class))
1183 (defmethod change-class ((instance funcallable-standard-object)
1184 (new-class funcallable-standard-class))
1185 (change-class-internal instance new-class))
1187 (defmethod change-class ((instance standard-object)
1188 (new-class funcallable-standard-class))
1189 (error "You can't change the class of ~S to ~S~@
1190 because it isn't already an instance with metaclass ~S."
1191 instance new-class 'standard-class))
1193 (defmethod change-class ((instance funcallable-standard-object)
1194 (new-class standard-class))
1195 (error "You can't change the class of ~S to ~S~@
1196 because it isn't already an instance with metaclass ~S."
1197 instance new-class 'funcallable-standard-class))
1199 (defmethod change-class ((instance t) (new-class-name symbol))
1200 (change-class instance (find-class new-class-name)))
1202 ;;;; The metaclass BUILT-IN-CLASS
1204 ;;;; This metaclass is something of a weird creature. By this point, all
1205 ;;;; instances of it which will exist have been created, and no instance
1206 ;;;; is ever created by calling MAKE-INSTANCE.
1208 ;;;; But, there are other parts of the protocol we must follow and those
1209 ;;;; definitions appear here.
1211 (defmethod shared-initialize :before
1212 ((class built-in-class) slot-names &rest initargs)
1213 (declare (ignore slot-names initargs))
1214 (error "attempt to initialize or reinitialize a built in class"))
1216 (defmethod class-direct-slots ((class built-in-class)) ())
1217 (defmethod class-slots ((class built-in-class)) ())
1218 (defmethod class-direct-default-initargs ((class built-in-class)) ())
1219 (defmethod class-default-initargs ((class built-in-class)) ())
1221 (defmethod validate-superclass ((c class) (s built-in-class))
1222 (or (eq s *the-class-t*)
1223 (eq s *the-class-stream*)))
1225 (defmethod validate-superclass ((c slot-class)
1226 (f forward-referenced-class))
1229 (defmethod add-dependent ((metaobject dependent-update-mixin) dependent)
1230 (pushnew dependent (plist-value metaobject 'dependents)))
1232 (defmethod remove-dependent ((metaobject dependent-update-mixin) dependent)
1233 (setf (plist-value metaobject 'dependents)
1234 (delete dependent (plist-value metaobject 'dependents))))
1236 (defmethod map-dependents ((metaobject dependent-update-mixin) function)
1237 (dolist (dependent (plist-value metaobject 'dependents))
1238 (funcall function dependent)))