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 ;;; CMUCL (Gerd PCL 2003-04-25) comment:
91 ;;; Compute an effective method for SLOT-VALUE-USING-CLASS, (SETF
92 ;;; SLOT-VALUE-USING-CLASS) or SLOT-BOUNDP-USING-CLASS for reading/
93 ;;; writing/testing effective slot SLOTD.
95 ;;; TYPE is one of the symbols READER, WRITER or BOUNDP, depending on
96 ;;; GF. Store the effective method in the effective slot definition
97 ;;; object itself; these GFs have special dispatch functions calling
98 ;;; effective methods directly retrieved from effective slot
99 ;;; definition objects, as an optimization.
101 ;;; FIXME: Change the function name to COMPUTE-SVUC-SLOTD-FUNCTION,
103 (defmethod compute-slot-accessor-info ((slotd effective-slot-definition)
105 (let* ((name (slot-value slotd 'name))
106 (class (slot-value slotd 'class))
107 (old-slotd (find-slot-definition class name))
108 (old-std-p (and old-slotd (slot-accessor-std-p old-slotd 'all))))
109 (multiple-value-bind (function std-p)
110 (if (eq *boot-state* 'complete)
111 (get-accessor-method-function gf type class slotd)
112 (get-optimized-std-accessor-method-function class slotd type))
113 (setf (slot-accessor-std-p slotd type) std-p)
114 (setf (slot-accessor-function slotd type) function))
115 (when (and old-slotd (not (eq old-std-p (slot-accessor-std-p slotd 'all))))
116 (push (cons class name) *pv-table-cache-update-info*))))
118 (defmethod slot-definition-allocation ((slotd structure-slot-definition))
121 ;;;; various class accessors that are a little more complicated than can be
122 ;;;; done with automatically generated reader methods
124 (defmethod class-prototype ((class std-class))
125 (with-slots (prototype) class
126 (or prototype (setq prototype (allocate-instance class)))))
128 (defmethod class-prototype ((class structure-class))
129 (with-slots (prototype wrapper defstruct-constructor) class
132 (if defstruct-constructor
133 (allocate-instance class)
134 (allocate-standard-instance wrapper))))))
136 (defmethod class-prototype ((class condition-class))
137 (with-slots (prototype) class
138 (or prototype (setf prototype (allocate-instance class)))))
140 (defmethod class-direct-default-initargs ((class slot-class))
141 (plist-value class 'direct-default-initargs))
143 (defmethod class-default-initargs ((class slot-class))
144 (plist-value class 'default-initargs))
146 (defmethod class-slot-cells ((class std-class))
147 (plist-value class 'class-slot-cells))
148 (defmethod (setf class-slot-cells) (new-value (class std-class))
149 (setf (plist-value class 'class-slot-cells) new-value))
151 ;;;; class accessors that are even a little bit more complicated than those
152 ;;;; above. These have a protocol for updating them, we must implement that
155 ;;; Maintaining the direct subclasses backpointers. The update methods are
156 ;;; here, the values are read by an automatically generated reader method.
157 (defmethod add-direct-subclass ((class class) (subclass class))
158 (with-slots (direct-subclasses) class
159 (pushnew subclass direct-subclasses)
161 (defmethod remove-direct-subclass ((class class) (subclass class))
162 (with-slots (direct-subclasses) class
163 (setq direct-subclasses (remove subclass direct-subclasses))
166 ;;; Maintaining the direct-methods and direct-generic-functions backpointers.
168 ;;; There are four generic functions involved, each has one method for the
169 ;;; class case and another method for the damned EQL specializers. All of
170 ;;; these are specified methods and appear in their specified place in the
173 ;;; ADD-DIRECT-METHOD
174 ;;; REMOVE-DIRECT-METHOD
175 ;;; SPECIALIZER-DIRECT-METHODS
176 ;;; SPECIALIZER-DIRECT-GENERIC-FUNCTIONS
178 ;;; In each case, we maintain one value which is a cons. The car is the list
179 ;;; methods. The cdr is a list of the generic functions. The cdr is always
181 (defmethod add-direct-method ((specializer class) (method method))
182 (with-slots (direct-methods) specializer
183 (setf (car direct-methods) (adjoin method (car direct-methods)) ;PUSH
184 (cdr direct-methods) ()))
186 (defmethod remove-direct-method ((specializer class) (method method))
187 (with-slots (direct-methods) specializer
188 (setf (car direct-methods) (remove method (car direct-methods))
189 (cdr direct-methods) ()))
192 (defmethod specializer-direct-methods ((specializer class))
193 (with-slots (direct-methods) specializer
194 (car direct-methods)))
196 (defmethod specializer-direct-generic-functions ((specializer class))
197 (with-slots (direct-methods) specializer
198 (or (cdr direct-methods)
199 (setf (cdr direct-methods)
201 (dolist (m (car direct-methods))
202 ;; the old PCL code used COLLECTING-ONCE which used
203 ;; #'EQ to check for newness
204 (pushnew (method-generic-function m) collect :test #'eq))
205 (nreverse collect))))))
207 ;;; This hash table is used to store the direct methods and direct generic
208 ;;; functions of EQL specializers. Each value in the table is the cons.
209 (defvar *eql-specializer-methods* (make-hash-table :test 'eql))
210 (defvar *class-eq-specializer-methods* (make-hash-table :test 'eq))
212 (defmethod specializer-method-table ((specializer eql-specializer))
213 *eql-specializer-methods*)
215 (defmethod specializer-method-table ((specializer class-eq-specializer))
216 *class-eq-specializer-methods*)
218 (defmethod add-direct-method ((specializer specializer-with-object)
220 (let* ((object (specializer-object specializer))
221 (table (specializer-method-table specializer))
222 (entry (gethash object table)))
225 (setf (gethash object table)
227 (setf (car entry) (adjoin method (car entry))
231 (defmethod remove-direct-method ((specializer specializer-with-object)
233 (let* ((object (specializer-object specializer))
234 (entry (gethash object (specializer-method-table specializer))))
236 (setf (car entry) (remove method (car entry))
240 (defmethod specializer-direct-methods ((specializer specializer-with-object))
241 (car (gethash (specializer-object specializer)
242 (specializer-method-table specializer))))
244 (defmethod specializer-direct-generic-functions ((specializer
245 specializer-with-object))
246 (let* ((object (specializer-object specializer))
247 (entry (gethash object (specializer-method-table specializer))))
252 (dolist (m (car entry))
253 (pushnew (method-generic-function m) collect :test #'eq))
254 (nreverse collect)))))))
256 (defun map-specializers (function)
257 (map-all-classes (lambda (class)
258 (funcall function (class-eq-specializer class))
259 (funcall function class)))
260 (maphash (lambda (object methods)
261 (declare (ignore methods))
262 (intern-eql-specializer object))
263 *eql-specializer-methods*)
264 (maphash (lambda (object specl)
265 (declare (ignore object))
266 (funcall function specl))
267 *eql-specializer-table*)
270 (defun map-all-generic-functions (function)
271 (let ((all-generic-functions (make-hash-table :test 'eq)))
272 (map-specializers (lambda (specl)
273 (dolist (gf (specializer-direct-generic-functions
275 (unless (gethash gf all-generic-functions)
276 (setf (gethash gf all-generic-functions) t)
277 (funcall function gf))))))
280 (defmethod shared-initialize :after ((specl class-eq-specializer)
283 (declare (ignore slot-names))
284 (setf (slot-value specl 'type) `(class-eq ,(specializer-class specl))))
286 (defmethod shared-initialize :after ((specl eql-specializer) slot-names &key)
287 (declare (ignore slot-names))
288 (setf (slot-value specl 'type)
289 `(eql ,(specializer-object specl)))
290 (setf (info :type :translator specl)
291 (constantly (make-member-type :members (list (specializer-object specl))))))
294 (defun real-load-defclass (name metaclass-name supers slots other
295 readers writers slot-names)
296 (with-single-package-locked-error (:symbol name "defining ~S as a class")
297 (%compiler-defclass name readers writers slot-names)
298 (let ((res (apply #'ensure-class name :metaclass metaclass-name
299 :direct-superclasses supers
301 :definition-source `((defclass ,name)
306 (setf (gdefinition 'load-defclass) #'real-load-defclass)
308 (defun ensure-class (name &rest args)
309 (apply #'ensure-class-using-class
310 (let ((class (find-class name nil)))
311 (when (and class (eq name (class-name class)))
312 ;; NAME is the proper name of CLASS, so redefine it
317 (defmethod ensure-class-using-class ((class null) name &rest args &key)
318 (multiple-value-bind (meta initargs)
319 (ensure-class-values class args)
320 (set-class-type-translation (class-prototype meta) name)
321 (setf class (apply #'make-instance meta :name name initargs))
322 (without-package-locks
323 (setf (find-class name) class))
324 (set-class-type-translation class name)
327 (defmethod ensure-class-using-class ((class pcl-class) name &rest args &key)
328 (multiple-value-bind (meta initargs)
329 (ensure-class-values class args)
330 (unless (eq (class-of class) meta)
331 (apply #'change-class class meta initargs))
332 (apply #'reinitialize-instance class initargs)
333 (without-package-locks
334 (setf (find-class name) class))
335 (set-class-type-translation class name)
338 (defmethod class-predicate-name ((class t))
343 ((not (legal-class-name-p s))
344 (error "~S is not a class or a legal class name." s))
346 (or (find-class s nil)
347 (make-instance 'forward-referenced-class
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 ;; KLUDGE: It seemed to me initially that there ought to be a way
365 ;; of collecting all the erroneous problems in one go, rather than
366 ;; this way of solving the problem of signalling the errors that
367 ;; we are required to, which stops at the first bogus input.
368 ;; However, after playing around a little, I couldn't find that
369 ;; way, so I've left it as is, but if someone does come up with a
370 ;; better way... -- CSR, 2002-09-08
371 (do ((direct-slots (getf initargs :direct-slots) (cdr direct-slots)))
372 ((endp direct-slots) nil)
373 (destructuring-bind (slot &rest more) direct-slots
374 (let ((slot-name (getf slot :name)))
375 (when (some (lambda (s) (eq slot-name (getf s :name))) more)
376 ;; FIXME: It's quite possible that we ought to define an
377 ;; SB-INT:PROGRAM-ERROR function to signal these and other
378 ;; errors throughout the codebase that are required to be
379 ;; of type PROGRAM-ERROR.
380 (error 'simple-program-error
381 :format-control "~@<There is more than one direct slot ~
383 :format-arguments (list slot-name)))
384 (do ((stuff slot (cddr stuff)))
386 (destructuring-bind (option value &rest more) stuff
388 ((and (member option '(:allocation :type
389 :initform :documentation))
391 (getf more option unsupplied))))
392 (error 'simple-program-error
393 :format-control "~@<Duplicate slot option ~S for ~
395 :format-arguments (list option slot-name)))
396 ((and (eq option :readers)
397 (notevery #'symbolp value))
398 (error 'simple-program-error
399 :format-control "~@<Slot reader names for slot ~
400 named ~S must be symbols.~:>"
401 :format-arguments (list slot-name)))
402 ((and (eq option :initargs)
403 (notevery #'symbolp value))
404 (error 'simple-program-error
405 :format-control "~@<Slot initarg names for slot ~
406 named ~S must be symbols.~:>"
407 :format-arguments (list slot-name)))))))))
408 (loop for (initarg . more) on (getf initargs :direct-default-initargs)
409 for name = (car initarg)
410 when (some (lambda (a) (eq (car a) name)) more)
411 do (error 'simple-program-error
412 :format-control "~@<Duplicate initialization argument ~
413 name ~S in :DEFAULT-INITARGS.~:>"
414 :format-arguments (list name class)))
416 (default-initargs 0))
417 (do ((args initargs (cddr args)))
421 (when (> (incf metaclass) 1)
422 (error 'simple-program-error
423 :format-control "~@<More than one :METACLASS ~
424 option specified.~:>")))
425 (:direct-default-initargs
426 (when (> (incf default-initargs) 1)
427 (error 'simple-program-error
428 :format-control "~@<More than one :DEFAULT-INITARGS ~
429 option specified.~:>"))))))
430 (remf initargs :metaclass)
431 (loop (unless (remf initargs :direct-superclasses) (return)))
432 (loop (unless (remf initargs :direct-slots) (return)))
436 (when (neq supplied-supers unsupplied)
437 (list :direct-superclasses (mapcar #'fix-super supplied-supers)))
438 (when (neq supplied-slots unsupplied)
439 (list :direct-slots supplied-slots))
442 (defmethod shared-initialize :after
445 &key (direct-superclasses nil direct-superclasses-p)
446 (direct-slots nil direct-slots-p)
447 (direct-default-initargs nil direct-default-initargs-p)
448 (predicate-name nil predicate-name-p))
449 (cond (direct-superclasses-p
450 (setq direct-superclasses
451 (or direct-superclasses
452 (list (if (funcallable-standard-class-p class)
453 *the-class-funcallable-standard-object*
454 *the-class-standard-object*))))
455 (dolist (superclass direct-superclasses)
456 (unless (validate-superclass class superclass)
457 (error "The class ~S was specified as a~%
458 super-class of the class ~S;~%~
459 but the meta-classes ~S and~%~S are incompatible.~@
460 Define a method for ~S to avoid this error."
461 superclass class (class-of superclass) (class-of class)
462 'validate-superclass)))
463 (setf (slot-value class 'direct-superclasses) direct-superclasses))
465 (setq direct-superclasses (slot-value class 'direct-superclasses))))
468 (setf (slot-value class 'direct-slots)
469 (mapcar (lambda (pl) (make-direct-slotd class pl))
471 (slot-value class 'direct-slots)))
472 (if direct-default-initargs-p
473 (setf (plist-value class 'direct-default-initargs)
474 direct-default-initargs)
475 (setq direct-default-initargs
476 (plist-value class 'direct-default-initargs)))
477 (setf (plist-value class 'class-slot-cells)
478 (let ((old-class-slot-cells (plist-value class 'class-slot-cells))
480 (dolist (dslotd direct-slots)
481 (when (eq :class (slot-definition-allocation dslotd))
483 (let* ((name (slot-definition-name dslotd))
484 (old (assoc name old-class-slot-cells)))
487 (member name slot-names))
488 (let* ((initfunction (slot-definition-initfunction dslotd))
489 (value (if initfunction
490 (funcall initfunction)
492 (push (cons name value) collect))
493 (push old collect)))))
495 (setq predicate-name (if predicate-name-p
496 (setf (slot-value class 'predicate-name)
497 (car predicate-name))
498 (or (slot-value class 'predicate-name)
499 (setf (slot-value class 'predicate-name)
500 (make-class-predicate-name (class-name
502 (add-direct-subclasses class direct-superclasses)
503 (make-class-predicate class predicate-name)
504 (update-class class nil)
505 (do* ((slots (slot-value class 'slots) (cdr slots))
507 ((null slots) (when dupes
509 ;; FIXME: the indentation request ("~4I")
510 ;; below appears not to do anything. Finding
511 ;; out why would be nice. -- CSR, 2003-04-24
512 "~@<slot names with the same SYMBOL-NAME but ~
513 different SYMBOL-PACKAGE (possible package problem) ~
514 for class ~S:~@:_~4I~<~@{~S~^~:@_~}~:>~@:>"
517 (let* ((slot (car slots))
518 (oslots (remove (slot-definition-name slot) (cdr slots)
519 :test #'string/= :key #'slot-definition-name)))
521 (pushnew (cons (slot-definition-name slot)
522 (mapcar #'slot-definition-name oslots))
524 :test #'string= :key #'car))))
525 (add-slot-accessors class direct-slots)
526 (make-preliminary-layout class))
528 (defmethod shared-initialize :after ((class forward-referenced-class)
529 slot-names &key &allow-other-keys)
530 (declare (ignore slot-names))
531 (make-preliminary-layout class))
533 (defvar *allow-forward-referenced-classes-in-cpl-p* nil)
535 ;;; Give CLASS a preliminary layout if it doesn't have one already, to
536 ;;; make it known to the type system.
537 (defun make-preliminary-layout (class)
538 (flet ((compute-preliminary-cpl (root)
539 (let ((*allow-forward-referenced-classes-in-cpl-p* t))
540 (compute-class-precedence-list root))))
541 (without-package-locks
542 (unless (class-finalized-p class)
543 (let ((name (class-name class)))
544 (setf (find-class name) class)
545 ;; KLUDGE: This is fairly horrible. We need to make a
546 ;; full-fledged CLASSOID here, not just tell the compiler that
547 ;; some class is forthcoming, because there are legitimate
548 ;; questions one can ask of the type system, implemented in
549 ;; terms of CLASSOIDs, involving forward-referenced classes. So.
550 (when (and (eq *boot-state* 'complete)
551 (null (find-classoid name nil)))
552 (setf (find-classoid name)
553 (make-standard-classoid :name name)))
554 (set-class-type-translation class name)
555 (let ((layout (make-wrapper 0 class))
556 (classoid (find-classoid name)))
557 (setf (layout-classoid layout) classoid)
558 (setf (classoid-pcl-class classoid) class)
559 (setf (slot-value class 'wrapper) layout)
560 (let ((cpl (compute-preliminary-cpl class)))
561 (setf (layout-inherits layout)
562 (order-layout-inherits
563 (map 'simple-vector #'class-wrapper
564 (reverse (rest cpl))))))
565 (register-layout layout :invalidate t)
566 (setf (classoid-layout classoid) layout)
567 (mapc #'make-preliminary-layout (class-direct-subclasses class))))))))
570 (defmethod shared-initialize :before ((class class) slot-names &key name)
571 (declare (ignore slot-names name))
572 ;; FIXME: Could this just be CLASS instead of `(CLASS ,CLASS)? If not,
573 ;; why not? (See also similar expression in !BOOTSTRAP-INITIALIZE-CLASS.)
574 (setf (slot-value class 'type) `(class ,class))
575 (setf (slot-value class 'class-eq-specializer)
576 (make-instance 'class-eq-specializer :class class)))
578 (defmethod reinitialize-instance :before ((class slot-class) &key)
579 (remove-direct-subclasses class (class-direct-superclasses class))
580 (remove-slot-accessors class (class-direct-slots class)))
582 (defmethod reinitialize-instance :after ((class slot-class)
585 (map-dependents class
587 (apply #'update-dependent class dependent initargs))))
589 (defmethod shared-initialize :after ((class condition-class) slot-names
590 &key direct-slots direct-superclasses)
591 (declare (ignore slot-names))
592 (let ((classoid (find-classoid (class-name class))))
593 (with-slots (wrapper class-precedence-list cpl-available-p
594 prototype predicate-name
595 (direct-supers direct-superclasses))
597 (setf (slot-value class 'direct-slots)
598 (mapcar (lambda (pl) (make-direct-slotd class pl))
600 (setf (slot-value class 'finalized-p) t)
601 (setf (classoid-pcl-class classoid) class)
602 (setq direct-supers direct-superclasses)
603 (setq wrapper (classoid-layout classoid))
604 (setq class-precedence-list (compute-class-precedence-list class))
605 (setq cpl-available-p t)
606 (add-direct-subclasses class direct-superclasses)
607 (setq predicate-name (make-class-predicate-name (class-name class)))
608 (make-class-predicate class predicate-name)
609 (setf (slot-value class 'slots) (compute-slots class))))
610 ;; Comment from Gerd's PCL, 2003-05-15:
612 ;; We don't ADD-SLOT-ACCESSORS here because we don't want to
613 ;; override condition accessors with generic functions. We do this
615 (update-pv-table-cache-info class))
617 (defmethod direct-slot-definition-class ((class condition-class)
619 (declare (ignore initargs))
620 (find-class 'condition-direct-slot-definition))
622 (defmethod effective-slot-definition-class ((class condition-class)
624 (declare (ignore initargs))
625 (find-class 'condition-effective-slot-definition))
627 (defmethod finalize-inheritance ((class condition-class))
628 (aver (slot-value class 'finalized-p))
631 (defmethod compute-effective-slot-definition
632 ((class condition-class) slot-name dslotds)
633 (let ((slotd (call-next-method)))
634 (setf (slot-definition-reader-function slotd)
636 (handler-case (condition-reader-function x slot-name)
637 ;; FIXME: FIND-SLOT-DEFAULT throws an error if the slot
638 ;; is unbound; maybe it should be a CELL-ERROR of some
640 (error () (values (slot-unbound class x slot-name))))))
641 (setf (slot-definition-writer-function slotd)
643 (condition-writer-function x v slot-name)))
644 (setf (slot-definition-boundp-function slotd)
646 (multiple-value-bind (v c)
647 (ignore-errors (condition-reader-function x slot-name))
652 (defmethod compute-slots ((class condition-class))
653 (mapcan (lambda (superclass)
654 (mapcar (lambda (dslotd)
655 (compute-effective-slot-definition
656 class (slot-definition-name dslotd) (list dslotd)))
657 (class-direct-slots superclass)))
658 (reverse (slot-value class 'class-precedence-list))))
660 (defmethod compute-slots :around ((class condition-class))
661 (let ((eslotds (call-next-method)))
662 (mapc #'initialize-internal-slot-functions eslotds)
665 (defmethod shared-initialize :after
666 ((slotd structure-slot-definition) slot-names &key
667 (allocation :instance) allocation-class)
668 (declare (ignore slot-names allocation-class))
669 (unless (eq allocation :instance)
670 (error "Structure slots must have :INSTANCE allocation.")))
672 (defun make-structure-class-defstruct-form (name direct-slots include)
673 (let* ((conc-name (format-symbol *package* "~S structure class " name))
674 (constructor (format-symbol *package* "~Aconstructor" conc-name))
675 (defstruct `(defstruct (,name
677 `((:include ,(class-name include))))
679 (:conc-name ,conc-name)
680 (:constructor ,constructor ())
682 ,@(mapcar (lambda (slot)
683 `(,(slot-definition-name slot)
686 (reader-names (mapcar (lambda (slotd)
687 (list 'slot-accessor name
688 (slot-definition-name slotd)
691 (writer-names (mapcar (lambda (slotd)
692 (list 'slot-accessor name
693 (slot-definition-name slotd)
697 (mapcar (lambda (slotd reader-name)
699 (slot-definition-defstruct-accessor-symbol
701 `(defun ,reader-name (obj)
702 (declare (type ,name obj))
704 direct-slots reader-names))
706 (mapcar (lambda (slotd writer-name)
708 (slot-definition-defstruct-accessor-symbol
710 `(defun ,writer-name (nv obj)
711 (declare (type ,name obj))
712 (setf (,accessor obj) nv))))
713 direct-slots writer-names))
717 ,@readers-init ,@writers-init
719 (values defstruct-form constructor reader-names writer-names)))
721 (defun make-defstruct-allocation-function (class)
722 (let ((dd (get-structure-dd (class-name class))))
724 (let ((instance (%make-instance (dd-length dd)))
725 (raw-index (dd-raw-index dd)))
726 (setf (%instance-layout instance)
727 (sb-kernel::compiler-layout-or-lose (dd-name dd)))
729 (setf (%instance-ref instance raw-index)
730 (make-array (dd-raw-length dd)
731 :element-type '(unsigned-byte 32))))
734 (defmethod shared-initialize :after
735 ((class structure-class)
737 &key (direct-superclasses nil direct-superclasses-p)
738 (direct-slots nil direct-slots-p)
739 direct-default-initargs
740 (predicate-name nil predicate-name-p))
741 (declare (ignore slot-names direct-default-initargs))
742 (if direct-superclasses-p
743 (setf (slot-value class 'direct-superclasses)
744 (or direct-superclasses
745 (setq direct-superclasses
746 (and (not (eq (class-name class) 'structure-object))
747 (list *the-class-structure-object*)))))
748 (setq direct-superclasses (slot-value class 'direct-superclasses)))
749 (let* ((name (class-name class))
750 (from-defclass-p (slot-value class 'from-defclass-p))
751 (defstruct-p (or from-defclass-p (not (structure-type-p name)))))
753 (setf (slot-value class 'direct-slots)
757 (let* ((slot-name (getf pl :name))
759 (format-symbol *package*
760 "~S structure class ~A"
762 (setq pl (list* :defstruct-accessor-symbol
764 (make-direct-slotd class pl))
766 (setq direct-slots (slot-value class 'direct-slots)))
768 (let ((include (car (slot-value class 'direct-superclasses))))
769 (multiple-value-bind (defstruct-form constructor reader-names writer-names)
770 (make-structure-class-defstruct-form name direct-slots include)
771 (unless (structure-type-p name) (eval defstruct-form))
772 (mapc (lambda (dslotd reader-name writer-name)
773 (let* ((reader (gdefinition reader-name))
774 (writer (when (gboundp writer-name)
775 (gdefinition writer-name))))
776 (setf (slot-value dslotd 'internal-reader-function)
778 (setf (slot-value dslotd 'internal-writer-function)
780 direct-slots reader-names writer-names)
781 (setf (slot-value class 'defstruct-form) defstruct-form)
782 (setf (slot-value class 'defstruct-constructor) constructor)))
783 (setf (slot-value class 'defstruct-constructor)
784 (make-defstruct-allocation-function class)))
785 (add-direct-subclasses class direct-superclasses)
786 (setf (slot-value class 'class-precedence-list)
787 (compute-class-precedence-list class))
788 (setf (slot-value class 'cpl-available-p) t)
789 (setf (slot-value class 'slots) (compute-slots class))
790 (let ((lclass (find-classoid (class-name class))))
791 (setf (classoid-pcl-class lclass) class)
792 (setf (slot-value class 'wrapper) (classoid-layout lclass)))
793 (setf (slot-value class 'finalized-p) t)
794 (update-pv-table-cache-info class)
795 (setq predicate-name (if predicate-name-p
796 (setf (slot-value class 'predicate-name)
797 (car predicate-name))
798 (or (slot-value class 'predicate-name)
799 (setf (slot-value class 'predicate-name)
800 (make-class-predicate-name
801 (class-name class))))))
802 (make-class-predicate class predicate-name)
803 (add-slot-accessors class direct-slots)))
805 (defmethod direct-slot-definition-class ((class structure-class) &rest initargs)
806 (declare (ignore initargs))
807 (find-class 'structure-direct-slot-definition))
809 (defmethod finalize-inheritance ((class structure-class))
810 nil) ; always finalized
812 (defun add-slot-accessors (class dslotds)
813 (fix-slot-accessors class dslotds 'add))
815 (defun remove-slot-accessors (class dslotds)
816 (fix-slot-accessors class dslotds 'remove))
818 (defun fix-slot-accessors (class dslotds add/remove)
819 (flet ((fix (gfspec name r/w)
820 (let ((gf (if (fboundp gfspec)
821 (without-package-locks
822 (ensure-generic-function gfspec))
823 (ensure-generic-function
824 gfspec :lambda-list (case r/w
826 (w '(new-value object)))))))
828 (r (if (eq add/remove 'add)
829 (add-reader-method class gf name)
830 (remove-reader-method class gf)))
831 (w (if (eq add/remove 'add)
832 (add-writer-method class gf name)
833 (remove-writer-method class gf)))))))
834 (dolist (dslotd dslotds)
835 (let ((slot-name (slot-definition-name dslotd)))
836 (dolist (r (slot-definition-readers dslotd))
837 (fix r slot-name 'r))
838 (dolist (w (slot-definition-writers dslotd))
839 (fix w slot-name 'w))))))
841 (defun add-direct-subclasses (class supers)
842 (dolist (super supers)
843 (unless (memq class (class-direct-subclasses class))
844 (add-direct-subclass super class))))
846 (defun remove-direct-subclasses (class supers)
847 (let ((old (class-direct-superclasses class)))
848 (dolist (o (set-difference old supers))
849 (remove-direct-subclass o class))))
851 (defmethod finalize-inheritance ((class std-class))
852 (update-class class t))
854 (defmethod finalize-inheritance ((class forward-referenced-class))
855 ;; FIXME: should we not be thinking a bit about what kinds of error
856 ;; we're throwing? Maybe we need a clos-error type to mix in? Or
857 ;; possibly a forward-referenced-class-error, though that's
858 ;; difficult given e.g. class precedence list calculations...
860 "~@<FINALIZE-INHERITANCE was called on a forward referenced class:~
865 (defun class-has-a-forward-referenced-superclass-p (class)
866 (or (forward-referenced-class-p class)
867 (some #'class-has-a-forward-referenced-superclass-p
868 (class-direct-superclasses class))))
870 ;;; This is called by :after shared-initialize whenever a class is initialized
871 ;;; or reinitialized. The class may or may not be finalized.
872 (defun update-class (class finalizep)
873 ;; Comment from Gerd Moellmann:
875 ;; Note that we can't simply delay the finalization when CLASS has
876 ;; no forward referenced superclasses because that causes bootstrap
878 (without-package-locks
879 (when (and (not finalizep)
880 (not (class-finalized-p class))
881 (not (class-has-a-forward-referenced-superclass-p class)))
882 (finalize-inheritance class)
883 (return-from update-class))
884 (when (or finalizep (class-finalized-p class)
885 (not (class-has-a-forward-referenced-superclass-p class)))
886 (setf (find-class (class-name class)) class)
887 (update-cpl class (compute-class-precedence-list class))
888 ;; This invocation of UPDATE-SLOTS, in practice, finalizes the
889 ;; class. The hoops above are to ensure that FINALIZE-INHERITANCE
890 ;; is called at finalization, so that MOP programmers can hook
891 ;; into the system as described in "Class Finalization Protocol"
892 ;; (section 5.5.2 of AMOP).
893 (update-slots class (compute-slots class))
894 (update-gfs-of-class class)
895 (update-initargs class (compute-default-initargs class))
896 (update-ctors 'finalize-inheritance :class class))
898 (dolist (sub (class-direct-subclasses class)) (update-class sub nil)))))
900 (defun update-cpl (class cpl)
901 (if (class-finalized-p class)
902 (unless (and (equal (class-precedence-list class) cpl)
904 (when (position :class (class-direct-slots c)
905 :key #'slot-definition-allocation)
907 ;; comment from the old CMU CL sources:
908 ;; Need to have the cpl setup before update-lisp-class-layout
909 ;; is called on CMU CL.
910 (setf (slot-value class 'class-precedence-list) cpl)
911 (setf (slot-value class 'cpl-available-p) t)
912 (force-cache-flushes class))
914 (setf (slot-value class 'class-precedence-list) cpl)
915 (setf (slot-value class 'cpl-available-p) t)))
916 (update-class-can-precede-p cpl))
918 (defun update-class-can-precede-p (cpl)
920 (let ((first (car cpl)))
921 (dolist (c (cdr cpl))
922 (pushnew c (slot-value first 'can-precede-list))))
923 (update-class-can-precede-p (cdr cpl))))
925 (defun class-can-precede-p (class1 class2)
926 (member class2 (class-can-precede-list class1)))
928 (defun update-slots (class eslotds)
929 (let ((instance-slots ())
931 (dolist (eslotd eslotds)
932 (let ((alloc (slot-definition-allocation eslotd)))
934 (:instance (push eslotd instance-slots))
935 (:class (push eslotd class-slots)))))
937 ;; If there is a change in the shape of the instances then the
938 ;; old class is now obsolete.
939 (let* ((nlayout (mapcar #'slot-definition-name
940 (sort instance-slots #'<
941 :key #'slot-definition-location)))
942 (nslots (length nlayout))
943 (nwrapper-class-slots (compute-class-slots class-slots))
944 (owrapper (when (class-finalized-p class)
945 (class-wrapper class)))
946 (olayout (when owrapper
947 (wrapper-instance-slots-layout owrapper)))
948 (owrapper-class-slots (and owrapper (wrapper-class-slots owrapper)))
950 (cond ((null owrapper)
951 (make-wrapper nslots class))
952 ((and (equal nlayout olayout)
954 (loop for o in owrapper-class-slots
955 for n in nwrapper-class-slots
956 do (unless (eq (car o) (car n)) (return t)))))
959 ;; This will initialize the new wrapper to have the
960 ;; same state as the old wrapper. We will then have
961 ;; to change that. This may seem like wasted work
962 ;; (and it is), but the spec requires that we call
963 ;; MAKE-INSTANCES-OBSOLETE.
964 (make-instances-obsolete class)
965 (class-wrapper class)))))
967 (with-slots (wrapper slots) class
968 (update-lisp-class-layout class nwrapper)
970 (wrapper-instance-slots-layout nwrapper) nlayout
971 (wrapper-class-slots nwrapper) nwrapper-class-slots
972 (wrapper-no-of-instance-slots nwrapper) nslots
974 (setf (slot-value class 'finalized-p) t)
975 (unless (eq owrapper nwrapper)
976 (update-pv-table-cache-info class)
977 (maybe-update-standard-class-locations class)))))
979 (defun compute-class-slots (eslotds)
981 (dolist (eslotd eslotds)
982 (push (assoc (slot-definition-name eslotd)
983 (class-slot-cells (slot-definition-class eslotd)))
987 (defun update-gfs-of-class (class)
988 (when (and (class-finalized-p class)
989 (let ((cpl (class-precedence-list class)))
990 (or (member *the-class-slot-class* cpl)
991 (member *the-class-standard-effective-slot-definition*
993 (let ((gf-table (make-hash-table :test 'eq)))
994 (labels ((collect-gfs (class)
995 (dolist (gf (specializer-direct-generic-functions class))
996 (setf (gethash gf gf-table) t))
997 (mapc #'collect-gfs (class-direct-superclasses class))))
999 (maphash (lambda (gf ignore)
1000 (declare (ignore ignore))
1001 (update-gf-dfun class gf))
1004 (defun update-initargs (class inits)
1005 (setf (plist-value class 'default-initargs) inits))
1007 (defmethod compute-default-initargs ((class slot-class))
1008 (let ((initargs (loop for c in (class-precedence-list class)
1009 append (class-direct-default-initargs c))))
1010 (delete-duplicates initargs :test #'eq :key #'car :from-end t)))
1012 ;;;; protocols for constructing direct and effective slot definitions
1014 (defmethod direct-slot-definition-class ((class std-class) &rest initargs)
1015 (declare (ignore initargs))
1016 (find-class 'standard-direct-slot-definition))
1018 (defun make-direct-slotd (class initargs)
1019 (let ((initargs (list* :class class initargs)))
1020 (apply #'make-instance
1021 (apply #'direct-slot-definition-class class initargs)
1024 (defmethod compute-slots ((class std-class))
1025 ;; As specified, we must call COMPUTE-EFFECTIVE-SLOT-DEFINITION once
1026 ;; for each different slot name we find in our superclasses. Each
1027 ;; call receives the class and a list of the dslotds with that name.
1028 ;; The list is in most-specific-first order.
1029 (let ((name-dslotds-alist ()))
1030 (dolist (c (class-precedence-list class))
1031 (dolist (slot (class-direct-slots c))
1032 (let* ((name (slot-definition-name slot))
1033 (entry (assq name name-dslotds-alist)))
1035 (push slot (cdr entry))
1036 (push (list name slot) name-dslotds-alist)))))
1037 (mapcar (lambda (direct)
1038 (compute-effective-slot-definition class
1040 (nreverse (cdr direct))))
1041 name-dslotds-alist)))
1043 (defmethod compute-slots ((class standard-class))
1046 (defmethod compute-slots :around ((class standard-class))
1047 (let ((eslotds (call-next-method))
1049 (dolist (eslotd eslotds eslotds)
1050 (setf (slot-definition-location eslotd)
1051 (case (slot-definition-allocation eslotd)
1055 (let* ((name (slot-definition-name eslotd))
1058 (slot-definition-allocation-class eslotd)
1059 ;; we get here if the user adds an extra slot
1061 (setf (slot-definition-allocation-class eslotd)
1063 ;; which raises the question of what we should
1064 ;; do if we find that said user has added a slot
1065 ;; with the same name as another slot...
1066 (cell (or (assq name (class-slot-cells from-class))
1067 (setf (class-slot-cells from-class)
1068 (cons (cons name +slot-unbound+)
1069 (class-slot-cells from-class))))))
1071 (if (eq +slot-unbound+ (cdr cell))
1072 ;; We may have inherited an initfunction
1073 (let ((initfun (slot-definition-initfunction eslotd)))
1075 (rplacd cell (funcall initfun))
1078 (unless (slot-definition-class eslotd)
1079 (setf (slot-definition-class eslotd) class))
1080 (initialize-internal-slot-functions eslotd))))
1082 (defmethod compute-slots ((class funcallable-standard-class))
1085 (defmethod compute-slots :around ((class funcallable-standard-class))
1086 (labels ((instance-slot-names (slotds)
1088 (dolist (slotd slotds (nreverse collect))
1089 (when (eq (slot-definition-allocation slotd) :instance)
1090 (push (slot-definition-name slotd) collect)))))
1091 ;; This sorts slots so that slots of classes later in the CPL
1092 ;; come before slots of other classes. This is crucial for
1093 ;; funcallable instances because it ensures that the slots of
1094 ;; FUNCALLABLE-STANDARD-OBJECT, which includes the slots of
1095 ;; KERNEL:FUNCALLABLE-INSTANCE, come first, which in turn
1096 ;; makes it possible to treat FUNCALLABLE-STANDARD-OBJECT as
1097 ;; a funcallable instance.
1098 (compute-layout (eslotds)
1100 (names (instance-slot-names eslotds)))
1102 (reverse (class-precedence-list class))
1103 (nreverse (nconc names first)))
1104 (dolist (ss (class-slots class))
1105 (let ((name (slot-definition-name ss)))
1106 (when (member name names)
1108 (setq names (delete name names)))))))))
1109 (let ((all-slotds (call-next-method))
1112 (dolist (slotd all-slotds)
1113 (case (slot-definition-allocation slotd)
1114 (:instance (push slotd instance-slots))
1115 (:class (push slotd class-slots))))
1116 (let ((layout (compute-layout instance-slots)))
1117 (dolist (slotd instance-slots)
1118 (setf (slot-definition-location slotd)
1119 (position (slot-definition-name slotd) layout))
1120 (initialize-internal-slot-functions slotd)))
1121 (dolist (slotd class-slots)
1122 (let ((name (slot-definition-name slotd))
1123 (from-class (slot-definition-allocation-class slotd)))
1124 (setf (slot-definition-location slotd)
1125 (assoc name (class-slot-cells from-class)))
1126 (aver (consp (slot-definition-location slotd)))
1127 (initialize-internal-slot-functions slotd)))
1130 (defmethod compute-slots ((class structure-class))
1131 (mapcan (lambda (superclass)
1132 (mapcar (lambda (dslotd)
1133 (compute-effective-slot-definition
1135 (slot-definition-name dslotd)
1137 (class-direct-slots superclass)))
1138 (reverse (slot-value class 'class-precedence-list))))
1140 (defmethod compute-slots :around ((class structure-class))
1141 (let ((eslotds (call-next-method)))
1142 (mapc #'initialize-internal-slot-functions eslotds)
1145 (defmethod compute-effective-slot-definition ((class slot-class) name dslotds)
1146 (declare (ignore name))
1147 (let* ((initargs (compute-effective-slot-definition-initargs class dslotds))
1148 (class (apply #'effective-slot-definition-class class initargs)))
1149 (apply #'make-instance class initargs)))
1151 (defmethod effective-slot-definition-class ((class std-class) &rest initargs)
1152 (declare (ignore initargs))
1153 (find-class 'standard-effective-slot-definition))
1155 (defmethod effective-slot-definition-class ((class structure-class) &rest initargs)
1156 (declare (ignore initargs))
1157 (find-class 'structure-effective-slot-definition))
1159 (defmethod compute-effective-slot-definition-initargs
1160 ((class slot-class) direct-slotds)
1166 (allocation-class nil)
1172 (dolist (slotd direct-slotds)
1175 (setq name (slot-definition-name slotd)
1178 (when (slot-definition-initfunction slotd)
1179 (setq initform (slot-definition-initform slotd)
1180 initfunction (slot-definition-initfunction slotd)
1183 (setq allocation (slot-definition-allocation slotd)
1184 allocation-class (slot-definition-class slotd)
1186 (setq initargs (append (slot-definition-initargs slotd) initargs))
1187 (let ((slotd-type (slot-definition-type slotd)))
1188 (setq type (cond ((eq type t) slotd-type)
1189 ((*subtypep type slotd-type) type)
1190 (t `(and ,type ,slotd-type)))))))
1193 :initfunction initfunction
1195 :allocation allocation
1196 :allocation-class allocation-class
1200 (defmethod compute-effective-slot-definition-initargs :around
1201 ((class structure-class) direct-slotds)
1202 (let ((slotd (car direct-slotds)))
1203 (list* :defstruct-accessor-symbol
1204 (slot-definition-defstruct-accessor-symbol slotd)
1205 :internal-reader-function
1206 (slot-definition-internal-reader-function slotd)
1207 :internal-writer-function
1208 (slot-definition-internal-writer-function slotd)
1209 (call-next-method))))
1211 ;;; NOTE: For bootstrapping considerations, these can't use MAKE-INSTANCE
1212 ;;; to make the method object. They have to use make-a-method which
1213 ;;; is a specially bootstrapped mechanism for making standard methods.
1214 (defmethod reader-method-class ((class slot-class) direct-slot &rest initargs)
1215 (declare (ignore direct-slot initargs))
1216 (find-class 'standard-reader-method))
1218 (defmethod add-reader-method ((class slot-class) generic-function slot-name)
1219 (add-method generic-function
1220 (make-a-method 'standard-reader-method
1222 (list (or (class-name class) 'object))
1224 (make-reader-method-function class slot-name)
1225 "automatically generated reader method"
1228 (defmethod writer-method-class ((class slot-class) direct-slot &rest initargs)
1229 (declare (ignore direct-slot initargs))
1230 (find-class 'standard-writer-method))
1232 (defmethod add-writer-method ((class slot-class) generic-function slot-name)
1233 (add-method generic-function
1234 (make-a-method 'standard-writer-method
1236 (list 'new-value (or (class-name class) 'object))
1237 (list *the-class-t* class)
1238 (make-writer-method-function class slot-name)
1239 "automatically generated writer method"
1242 (defmethod add-boundp-method ((class slot-class) generic-function slot-name)
1243 (add-method generic-function
1244 (make-a-method 'standard-boundp-method
1246 (list (or (class-name class) 'object))
1248 (make-boundp-method-function class slot-name)
1249 "automatically generated boundp method"
1252 (defmethod remove-reader-method ((class slot-class) generic-function)
1253 (let ((method (get-method generic-function () (list class) nil)))
1254 (when method (remove-method generic-function method))))
1256 (defmethod remove-writer-method ((class slot-class) generic-function)
1258 (get-method generic-function () (list *the-class-t* class) nil)))
1259 (when method (remove-method generic-function method))))
1261 (defmethod remove-boundp-method ((class slot-class) generic-function)
1262 (let ((method (get-method generic-function () (list class) nil)))
1263 (when method (remove-method generic-function method))))
1265 ;;; MAKE-READER-METHOD-FUNCTION and MAKE-WRITE-METHOD function are NOT
1266 ;;; part of the standard protocol. They are however useful, PCL makes
1267 ;;; use of them internally and documents them for PCL users.
1269 ;;; *** This needs work to make type testing by the writer functions which
1270 ;;; *** do type testing faster. The idea would be to have one constructor
1271 ;;; *** for each possible type test.
1273 ;;; *** There is a subtle bug here which is going to have to be fixed.
1274 ;;; *** Namely, the simplistic use of the template has to be fixed. We
1275 ;;; *** have to give the OPTIMIZE-SLOT-VALUE method the user might have
1276 ;;; *** defined for this metaclass a chance to run.
1278 (defmethod make-reader-method-function ((class slot-class) slot-name)
1279 (make-std-reader-method-function (class-name class) slot-name))
1281 (defmethod make-writer-method-function ((class slot-class) slot-name)
1282 (make-std-writer-method-function (class-name class) slot-name))
1284 (defmethod make-boundp-method-function ((class slot-class) slot-name)
1285 (make-std-boundp-method-function (class-name class) slot-name))
1287 (defmethod compatible-meta-class-change-p (class proto-new-class)
1288 (eq (class-of class) (class-of proto-new-class)))
1290 (defmethod validate-superclass ((class class) (new-super class))
1291 (or (eq new-super *the-class-t*)
1292 (eq (class-of class) (class-of new-super))))
1294 (defmethod validate-superclass ((class standard-class) (new-super std-class))
1295 (let ((new-super-meta-class (class-of new-super)))
1296 (or (eq new-super-meta-class *the-class-std-class*)
1297 (eq (class-of class) new-super-meta-class))))
1299 ;;; What this does depends on which of the four possible values of
1300 ;;; LAYOUT-INVALID the PCL wrapper has; the simplest case is when it
1301 ;;; is (:FLUSH <wrapper>) or (:OBSOLETE <wrapper>), when there is
1302 ;;; nothing to do, as the new wrapper has already been created. If
1303 ;;; LAYOUT-INVALID returns NIL, then we invalidate it (setting it to
1304 ;;; (:FLUSH <wrapper>); UPDATE-SLOTS later gets to choose whether or
1305 ;;; not to "upgrade" this to (:OBSOLETE <wrapper>).
1307 ;;; This leaves the case where LAYOUT-INVALID returns T, which happens
1308 ;;; when REGISTER-LAYOUT has invalidated a superclass of CLASS (which
1309 ;;; invalidated all the subclasses in SB-KERNEL land). Again, here we
1310 ;;; must flush the caches and allow UPDATE-SLOTS to decide whether to
1311 ;;; obsolete the wrapper.
1313 ;;; FIXME: either here or in INVALID-WRAPPER-P looks like a good place
1314 ;;; for (AVER (NOT (EQ (LAYOUT-INVALID OWRAPPER)
1315 ;;; :UNINITIALIZED)))
1317 ;;; Thanks to Gerd Moellmann for the explanation. -- CSR, 2002-10-29
1318 (defun force-cache-flushes (class)
1319 (let* ((owrapper (class-wrapper class)))
1320 ;; We only need to do something if the wrapper is still valid. If
1321 ;; the wrapper isn't valid, state will be FLUSH or OBSOLETE, and
1322 ;; both of those will already be doing what we want. In
1323 ;; particular, we must be sure we never change an OBSOLETE into a
1324 ;; FLUSH since OBSOLETE means do what FLUSH does and then some.
1325 (when (or (not (invalid-wrapper-p owrapper))
1326 ;; KLUDGE: despite the observations above, this remains
1327 ;; a violation of locality or what might be considered
1328 ;; good style. There has to be a better way! -- CSR,
1330 (eq (layout-invalid owrapper) t))
1331 (let ((nwrapper (make-wrapper (wrapper-no-of-instance-slots owrapper)
1333 (setf (wrapper-instance-slots-layout nwrapper)
1334 (wrapper-instance-slots-layout owrapper))
1335 (setf (wrapper-class-slots nwrapper)
1336 (wrapper-class-slots owrapper))
1338 (update-lisp-class-layout class nwrapper)
1339 (setf (slot-value class 'wrapper) nwrapper)
1340 ;; Use :OBSOLETE instead of :FLUSH if any superclass has
1342 (if (find-if (lambda (x)
1343 (and (consp x) (eq :obsolete (car x))))
1344 (layout-inherits owrapper)
1345 :key #'layout-invalid)
1346 (invalidate-wrapper owrapper :obsolete nwrapper)
1347 (invalidate-wrapper owrapper :flush nwrapper)))))))
1349 (defun flush-cache-trap (owrapper nwrapper instance)
1350 (declare (ignore owrapper))
1351 (set-wrapper instance nwrapper))
1353 ;;; MAKE-INSTANCES-OBSOLETE can be called by user code. It will cause
1354 ;;; the next access to the instance (as defined in 88-002R) to trap
1355 ;;; through the UPDATE-INSTANCE-FOR-REDEFINED-CLASS mechanism.
1356 (defmethod make-instances-obsolete ((class std-class))
1357 (let* ((owrapper (class-wrapper class))
1358 (nwrapper (make-wrapper (wrapper-no-of-instance-slots owrapper)
1360 (setf (wrapper-instance-slots-layout nwrapper)
1361 (wrapper-instance-slots-layout owrapper))
1362 (setf (wrapper-class-slots nwrapper)
1363 (wrapper-class-slots owrapper))
1365 (update-lisp-class-layout class nwrapper)
1366 (setf (slot-value class 'wrapper) nwrapper)
1367 (invalidate-wrapper owrapper :obsolete nwrapper)
1370 (defmethod make-instances-obsolete ((class symbol))
1371 (make-instances-obsolete (find-class class))
1372 ;; ANSI wants the class name when called with a symbol.
1375 ;;; OBSOLETE-INSTANCE-TRAP is the internal trap that is called when we
1376 ;;; see an obsolete instance. The times when it is called are:
1377 ;;; - when the instance is involved in method lookup
1378 ;;; - when attempting to access a slot of an instance
1380 ;;; It is not called by class-of, wrapper-of, or any of the low-level
1381 ;;; instance access macros.
1383 ;;; Of course these times when it is called are an internal
1384 ;;; implementation detail of PCL and are not part of the documented
1385 ;;; description of when the obsolete instance update happens. The
1386 ;;; documented description is as it appears in 88-002R.
1388 ;;; This has to return the new wrapper, so it counts on all the
1389 ;;; methods on obsolete-instance-trap-internal to return the new
1390 ;;; wrapper. It also does a little internal error checking to make
1391 ;;; sure that the traps are only happening when they should, and that
1392 ;;; the trap methods are computing appropriate new wrappers.
1394 ;;; OBSOLETE-INSTANCE-TRAP might be called on structure instances
1395 ;;; after a structure is redefined. In most cases,
1396 ;;; OBSOLETE-INSTANCE-TRAP will not be able to fix the old instance,
1397 ;;; so it must signal an error. The hard part of this is that the
1398 ;;; error system and debugger might cause OBSOLETE-INSTANCE-TRAP to be
1399 ;;; called again, so in that case, we have to return some reasonable
1400 ;;; wrapper, instead.
1402 (defvar *in-obsolete-instance-trap* nil)
1403 (defvar *the-wrapper-of-structure-object*
1404 (class-wrapper (find-class 'structure-object)))
1406 (define-condition obsolete-structure (error)
1407 ((datum :reader obsolete-structure-datum :initarg :datum))
1409 (lambda (condition stream)
1410 ;; Don't try to print the structure, since it probably won't work.
1412 "~@<obsolete structure error for a structure of type ~2I~_~S~:>"
1413 (type-of (obsolete-structure-datum condition))))))
1415 (defun obsolete-instance-trap (owrapper nwrapper instance)
1416 (if (not (pcl-instance-p instance))
1417 (if *in-obsolete-instance-trap*
1418 *the-wrapper-of-structure-object*
1419 (let ((*in-obsolete-instance-trap* t))
1420 (error 'obsolete-structure :datum instance)))
1421 (let* ((class (wrapper-class* nwrapper))
1422 (copy (allocate-instance class)) ;??? allocate-instance ???
1423 (olayout (wrapper-instance-slots-layout owrapper))
1424 (nlayout (wrapper-instance-slots-layout nwrapper))
1425 (oslots (get-slots instance))
1426 (nslots (get-slots copy))
1427 (oclass-slots (wrapper-class-slots owrapper))
1432 ;; local --> local transfer value
1433 ;; local --> shared discard value, discard slot
1434 ;; local --> -- discard slot
1435 ;; shared --> local transfer value
1436 ;; shared --> shared -- (cf SHARED-INITIALIZE :AFTER STD-CLASS)
1437 ;; shared --> -- discard value
1438 ;; -- --> local add slot
1441 ;; Collect class slots from inherited wrappers. Needed for
1442 ;; shared -> local transfers of inherited slots.
1443 (let ((inherited (layout-inherits owrapper)))
1444 (loop for i from (1- (length inherited)) downto 0
1445 for layout = (aref inherited i)
1446 when (typep layout 'wrapper)
1447 do (dolist (slot (wrapper-class-slots layout))
1448 (pushnew slot oclass-slots :key #'car))))
1450 ;; Go through all the old local slots.
1452 (dolist (name olayout)
1453 (let ((npos (posq name nlayout)))
1455 (setf (clos-slots-ref nslots npos)
1456 (clos-slots-ref oslots opos))
1458 (push name discarded)
1459 (unless (eq (clos-slots-ref oslots opos) +slot-unbound+)
1460 (setf (getf plist name) (clos-slots-ref oslots opos))))))
1463 ;; Go through all the old shared slots.
1464 (dolist (oclass-slot-and-val oclass-slots)
1465 (let ((name (car oclass-slot-and-val))
1466 (val (cdr oclass-slot-and-val)))
1467 (let ((npos (posq name nlayout)))
1469 (setf (clos-slots-ref nslots npos) val)))))
1471 ;; Go through all the new local slots to compute the added slots.
1472 (dolist (nlocal nlayout)
1473 (unless (or (memq nlocal olayout)
1474 (assq nlocal oclass-slots))
1475 (push nlocal added)))
1477 (swap-wrappers-and-slots instance copy)
1479 (update-instance-for-redefined-class instance
1485 (defun change-class-internal (instance new-class initargs)
1486 (let* ((old-class (class-of instance))
1487 (copy (allocate-instance new-class))
1488 (new-wrapper (get-wrapper copy))
1489 (old-wrapper (class-wrapper old-class))
1490 (old-layout (wrapper-instance-slots-layout old-wrapper))
1491 (new-layout (wrapper-instance-slots-layout new-wrapper))
1492 (old-slots (get-slots instance))
1493 (new-slots (get-slots copy))
1494 (old-class-slots (wrapper-class-slots old-wrapper)))
1496 ;; "The values of local slots specified by both the class CTO and
1497 ;; CFROM are retained. If such a local slot was unbound, it
1498 ;; remains unbound."
1499 (let ((new-position 0))
1500 (dolist (new-slot new-layout)
1501 (let ((old-position (posq new-slot old-layout)))
1503 (setf (clos-slots-ref new-slots new-position)
1504 (clos-slots-ref old-slots old-position))))
1505 (incf new-position)))
1507 ;; "The values of slots specified as shared in the class CFROM and
1508 ;; as local in the class CTO are retained."
1509 (dolist (slot-and-val old-class-slots)
1510 (let ((position (posq (car slot-and-val) new-layout)))
1512 (setf (clos-slots-ref new-slots position) (cdr slot-and-val)))))
1514 ;; Make the copy point to the old instance's storage, and make the
1515 ;; old instance point to the new storage.
1516 (swap-wrappers-and-slots instance copy)
1518 (apply #'update-instance-for-different-class copy instance initargs)
1521 (defmethod change-class ((instance standard-object)
1522 (new-class standard-class)
1524 (change-class-internal instance new-class initargs))
1526 (defmethod change-class ((instance funcallable-standard-object)
1527 (new-class funcallable-standard-class)
1529 (change-class-internal instance new-class initargs))
1531 (defmethod change-class ((instance standard-object)
1532 (new-class funcallable-standard-class)
1534 (declare (ignore initargs))
1535 (error "You can't change the class of ~S to ~S~@
1536 because it isn't already an instance with metaclass ~S."
1537 instance new-class 'standard-class))
1539 (defmethod change-class ((instance funcallable-standard-object)
1540 (new-class standard-class)
1542 (declare (ignore initargs))
1543 (error "You can't change the class of ~S to ~S~@
1544 because it isn't already an instance with metaclass ~S."
1545 instance new-class 'funcallable-standard-class))
1547 (defmethod change-class ((instance t) (new-class-name symbol) &rest initargs)
1548 (apply #'change-class instance (find-class new-class-name) initargs))
1550 ;;;; The metaclass BUILT-IN-CLASS
1552 ;;;; This metaclass is something of a weird creature. By this point, all
1553 ;;;; instances of it which will exist have been created, and no instance
1554 ;;;; is ever created by calling MAKE-INSTANCE.
1556 ;;;; But, there are other parts of the protocol we must follow and those
1557 ;;;; definitions appear here.
1559 (defmethod shared-initialize :before
1560 ((class built-in-class) slot-names &rest initargs)
1561 (declare (ignore slot-names initargs))
1562 (error "attempt to initialize or reinitialize a built in class"))
1564 (defmethod class-direct-slots ((class built-in-class)) ())
1565 (defmethod class-slots ((class built-in-class)) ())
1566 (defmethod class-direct-default-initargs ((class built-in-class)) ())
1567 (defmethod class-default-initargs ((class built-in-class)) ())
1569 (defmethod validate-superclass ((c class) (s built-in-class))
1570 (or (eq s *the-class-t*)
1571 (eq s *the-class-stream*)))
1573 ;;; Some necessary methods for FORWARD-REFERENCED-CLASS
1574 (defmethod class-direct-slots ((class forward-referenced-class)) ())
1575 (defmethod class-direct-default-initargs ((class forward-referenced-class)) ())
1576 (macrolet ((def (method)
1577 `(defmethod ,method ((class forward-referenced-class))
1578 (error "~@<~I~S was called on a forward referenced class:~2I~_~S~:>"
1580 (def class-default-initargs)
1581 (def class-precedence-list)
1584 (defmethod validate-superclass ((c slot-class)
1585 (f forward-referenced-class))
1588 (defmethod add-dependent ((metaobject dependent-update-mixin) dependent)
1589 (pushnew dependent (plist-value metaobject 'dependents)))
1591 (defmethod remove-dependent ((metaobject dependent-update-mixin) dependent)
1592 (setf (plist-value metaobject 'dependents)
1593 (delete dependent (plist-value metaobject 'dependents))))
1595 (defmethod map-dependents ((metaobject dependent-update-mixin) function)
1596 (dolist (dependent (plist-value metaobject 'dependents))
1597 (funcall function dependent)))