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 (defmethod shared-initialize :after ((object documentation-mixin)
123 &key (documentation nil documentation-p))
124 (declare (ignore slot-names))
125 (when documentation-p
126 (setf (plist-value object 'documentation) documentation)))
128 ;;; default if DOC-TYPE doesn't match one of the specified types
129 (defmethod documentation (object doc-type)
130 (warn "unsupported DOCUMENTATION: type ~S for object ~S"
135 ;;; default if DOC-TYPE doesn't match one of the specified types
136 (defmethod (setf documentation) (new-value object doc-type)
137 ;; CMU CL made this an error, but since ANSI says that even for supported
138 ;; doc types an implementation is permitted to discard docs at any time
139 ;; for any reason, this feels to me more like a warning. -- WHN 19991214
140 (warn "discarding unsupported DOCUMENTATION of type ~S for object ~S"
145 (defmethod documentation ((object documentation-mixin) doc-type)
146 (declare (ignore doc-type))
147 (plist-value object 'documentation))
149 (defmethod (setf documentation) (new-value
150 (object documentation-mixin)
152 (declare (ignore doc-type))
153 (setf (plist-value object 'documentation) new-value))
155 (defmethod documentation ((slotd standard-slot-definition) doc-type)
156 (declare (ignore doc-type))
157 (slot-value slotd 'documentation))
159 (defmethod (setf documentation) (new-value
160 (slotd standard-slot-definition)
162 (declare (ignore doc-type))
163 (setf (slot-value slotd 'documentation) new-value))
165 ;;;; various class accessors that are a little more complicated than can be
166 ;;;; done with automatically generated reader methods
168 (defmethod class-prototype ((class std-class))
169 (with-slots (prototype) class
170 (or prototype (setq prototype (allocate-instance class)))))
172 (defmethod class-prototype ((class structure-class))
173 (with-slots (prototype wrapper defstruct-constructor) class
176 (if defstruct-constructor
177 (allocate-instance class)
178 (allocate-standard-instance wrapper))))))
180 (defmethod class-direct-default-initargs ((class slot-class))
181 (plist-value class 'direct-default-initargs))
183 (defmethod class-default-initargs ((class slot-class))
184 (plist-value class 'default-initargs))
186 (defmethod class-slot-cells ((class std-class))
187 (plist-value class 'class-slot-cells))
189 ;;;; class accessors that are even a little bit more complicated than those
190 ;;;; above. These have a protocol for updating them, we must implement that
193 ;;; Maintaining the direct subclasses backpointers. The update methods are
194 ;;; here, the values are read by an automatically generated reader method.
195 (defmethod add-direct-subclass ((class class) (subclass class))
196 (with-slots (direct-subclasses) class
197 (pushnew subclass direct-subclasses)
199 (defmethod remove-direct-subclass ((class class) (subclass class))
200 (with-slots (direct-subclasses) class
201 (setq direct-subclasses (remove subclass direct-subclasses))
204 ;;; Maintaining the direct-methods and direct-generic-functions backpointers.
206 ;;; There are four generic functions involved, each has one method for the
207 ;;; class case and another method for the damned EQL specializers. All of
208 ;;; these are specified methods and appear in their specified place in the
211 ;;; ADD-DIRECT-METHOD
212 ;;; REMOVE-DIRECT-METHOD
213 ;;; SPECIALIZER-DIRECT-METHODS
214 ;;; SPECIALIZER-DIRECT-GENERIC-FUNCTIONS
216 ;;; In each case, we maintain one value which is a cons. The car is the list
217 ;;; methods. The cdr is a list of the generic functions. The cdr is always
219 (defmethod add-direct-method ((specializer class) (method method))
220 (with-slots (direct-methods) specializer
221 (setf (car direct-methods) (adjoin method (car direct-methods)) ;PUSH
222 (cdr direct-methods) ()))
224 (defmethod remove-direct-method ((specializer class) (method method))
225 (with-slots (direct-methods) specializer
226 (setf (car direct-methods) (remove method (car direct-methods))
227 (cdr direct-methods) ()))
230 (defmethod specializer-direct-methods ((specializer class))
231 (with-slots (direct-methods) specializer
232 (car direct-methods)))
234 (defmethod specializer-direct-generic-functions ((specializer class))
235 (with-slots (direct-methods) specializer
236 (or (cdr direct-methods)
237 (setf (cdr direct-methods)
239 (dolist (m (car direct-methods))
240 ;; the old PCL code used COLLECTING-ONCE which used
241 ;; #'EQ to check for newness
242 (pushnew (method-generic-function m) collect :test #'eq))
243 (nreverse collect))))))
245 ;;; This hash table is used to store the direct methods and direct generic
246 ;;; functions of EQL specializers. Each value in the table is the cons.
247 (defvar *eql-specializer-methods* (make-hash-table :test 'eql))
248 (defvar *class-eq-specializer-methods* (make-hash-table :test 'eq))
250 (defmethod specializer-method-table ((specializer eql-specializer))
251 *eql-specializer-methods*)
253 (defmethod specializer-method-table ((specializer class-eq-specializer))
254 *class-eq-specializer-methods*)
256 (defmethod add-direct-method ((specializer specializer-with-object)
258 (let* ((object (specializer-object specializer))
259 (table (specializer-method-table specializer))
260 (entry (gethash object table)))
263 (setf (gethash object table)
265 (setf (car entry) (adjoin method (car entry))
269 (defmethod remove-direct-method ((specializer specializer-with-object)
271 (let* ((object (specializer-object specializer))
272 (entry (gethash object (specializer-method-table specializer))))
274 (setf (car entry) (remove method (car entry))
278 (defmethod specializer-direct-methods ((specializer specializer-with-object))
279 (car (gethash (specializer-object specializer)
280 (specializer-method-table specializer))))
282 (defmethod specializer-direct-generic-functions ((specializer
283 specializer-with-object))
284 (let* ((object (specializer-object specializer))
285 (entry (gethash object (specializer-method-table specializer))))
290 (dolist (m (car entry))
291 (pushnew (method-generic-function m) collect :test #'eq))
292 (nreverse collect)))))))
294 (defun map-specializers (function)
295 (map-all-classes (lambda (class)
296 (funcall function (class-eq-specializer class))
297 (funcall function class)))
298 (maphash (lambda (object methods)
299 (declare (ignore methods))
300 (intern-eql-specializer object))
301 *eql-specializer-methods*)
302 (maphash (lambda (object specl)
303 (declare (ignore object))
304 (funcall function specl))
305 *eql-specializer-table*)
308 (defun map-all-generic-functions (function)
309 (let ((all-generic-functions (make-hash-table :test 'eq)))
310 (map-specializers (lambda (specl)
311 (dolist (gf (specializer-direct-generic-functions
313 (unless (gethash gf all-generic-functions)
314 (setf (gethash gf all-generic-functions) t)
315 (funcall function gf))))))
318 (defmethod shared-initialize :after ((specl class-eq-specializer)
321 (declare (ignore slot-names))
322 (setf (slot-value specl 'type) `(class-eq ,(specializer-class specl))))
324 (defmethod shared-initialize :after ((specl eql-specializer) slot-names &key)
325 (declare (ignore slot-names))
326 (setf (slot-value specl 'type) `(eql ,(specializer-object specl))))
328 (defun real-load-defclass (name metaclass-name supers slots other)
329 (let ((res (apply #'ensure-class name :metaclass metaclass-name
330 :direct-superclasses supers
332 :definition-source `((defclass ,name)
337 (setf (gdefinition 'load-defclass) #'real-load-defclass)
339 (defun ensure-class (name &rest all)
340 (apply #'ensure-class-using-class (find-class name nil) name all))
342 (defmethod ensure-class-using-class ((class null) name &rest args &key)
343 (multiple-value-bind (meta initargs)
344 (ensure-class-values class args)
345 (set-class-type-translation (class-prototype meta) name)
346 (setf class (apply #'make-instance meta :name name initargs)
347 (find-class name) class)
348 (set-class-type-translation class name)
351 (defmethod ensure-class-using-class ((class pcl-class) name &rest args &key)
352 (multiple-value-bind (meta initargs)
353 (ensure-class-values class args)
354 (unless (eq (class-of class) meta)
355 (apply #'change-class class meta initargs))
356 (apply #'reinitialize-instance class initargs)
357 (setf (find-class name) class)
358 (set-class-type-translation class name)
361 (defmethod class-predicate-name ((class t))
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)
370 (make-instance 'forward-referenced-class
373 (defun ensure-class-values (class args)
374 (let* ((initargs (copy-list args))
375 (unsupplied (list 1))
376 (supplied-meta (getf initargs :metaclass unsupplied))
377 (supplied-supers (getf initargs :direct-superclasses unsupplied))
378 (supplied-slots (getf initargs :direct-slots unsupplied))
380 (cond ((neq supplied-meta unsupplied)
381 (find-class supplied-meta))
383 (forward-referenced-class-p class))
384 *the-class-standard-class*)
387 ;; KLUDGE: It seemed to me initially that there ought to be a way
388 ;; of collecting all the erroneous problems in one go, rather than
389 ;; this way of solving the problem of signalling the errors that
390 ;; we are required to, which stops at the first bogus input.
391 ;; However, after playing around a little, I couldn't find that
392 ;; way, so I've left it as is, but if someone does come up with a
393 ;; better way... -- CSR, 2002-09-08
394 (do ((direct-slots (getf initargs :direct-slots) (cdr direct-slots)))
395 ((endp direct-slots) nil)
396 (destructuring-bind (slot &rest more) direct-slots
397 (let ((slot-name (getf slot :name)))
398 (when (some (lambda (s) (eq slot-name (getf s :name))) more)
399 ;; FIXME: It's quite possible that we ought to define an
400 ;; SB-INT:PROGRAM-ERROR function to signal these and other
401 ;; errors throughout the codebase that are required to be
402 ;; of type PROGRAM-ERROR.
403 (error 'simple-program-error
404 :format-control "~@<There is more than one direct slot ~
406 :format-arguments (list slot-name)))
407 (do ((stuff slot (cddr stuff)))
409 (destructuring-bind (option value &rest more) stuff
411 ((and (member option '(:allocation :type
412 :initform :documentation))
414 (getf more option unsupplied))))
415 (error 'simple-program-error
416 :format-control "~@<Duplicate slot option ~S for ~
418 :format-arguments (list option slot-name)))
419 ((and (eq option :readers)
420 (notevery #'symbolp value))
421 (error 'simple-program-error
422 :format-control "~@<Slot reader names for slot ~
423 named ~S must be symbols.~:>"
424 :format-arguments (list slot-name)))
425 ((and (eq option :initargs)
426 (notevery #'symbolp value))
427 (error 'simple-program-error
428 :format-control "~@<Slot initarg names for slot ~
429 named ~S must be symbols.~:>"
430 :format-arguments (list slot-name)))))))))
431 (loop for (initarg . more) on (getf initargs :direct-default-initargs)
432 for name = (car initarg)
433 when (some (lambda (a) (eq (car a) name)) more)
434 do (error 'simple-program-error
435 :format-control "~@<Duplicate initialization argument ~
436 name ~S in :DEFAULT-INITARGS.~:>"
437 :format-arguments (list name class)))
439 (default-initargs 0))
440 (do ((args initargs (cddr args)))
444 (when (> (incf metaclass) 1)
445 (error 'simple-program-error
446 :format-control "~@<More than one :METACLASS ~
447 option specified.~:>")))
448 (:direct-default-initargs
449 (when (> (incf default-initargs) 1)
450 (error 'simple-program-error
451 :format-control "~@<More than one :DEFAULT-INITARGS ~
452 option specified.~:>"))))))
453 (remf initargs :metaclass)
454 (loop (unless (remf initargs :direct-superclasses) (return)))
455 (loop (unless (remf initargs :direct-slots) (return)))
459 (when (neq supplied-supers unsupplied)
460 (list :direct-superclasses (mapcar #'fix-super supplied-supers)))
461 (when (neq supplied-slots unsupplied)
462 (list :direct-slots supplied-slots))
465 (defmethod shared-initialize :after
468 &key (direct-superclasses nil direct-superclasses-p)
469 (direct-slots nil direct-slots-p)
470 (direct-default-initargs nil direct-default-initargs-p)
471 (predicate-name nil predicate-name-p))
472 (declare (ignore slot-names))
473 (cond (direct-superclasses-p
474 (setq direct-superclasses
475 (or direct-superclasses
476 (list (if (funcallable-standard-class-p class)
477 *the-class-funcallable-standard-object*
478 *the-class-standard-object*))))
479 (dolist (superclass direct-superclasses)
480 (unless (validate-superclass class superclass)
481 (error "The class ~S was specified as a~%
482 super-class of the class ~S;~%~
483 but the meta-classes ~S and~%~S are incompatible.~@
484 Define a method for ~S to avoid this error."
485 superclass class (class-of superclass) (class-of class)
486 'validate-superclass)))
487 (setf (slot-value class 'direct-superclasses) direct-superclasses))
489 (setq direct-superclasses (slot-value class 'direct-superclasses))))
492 (setf (slot-value class 'direct-slots)
493 (mapcar (lambda (pl) (make-direct-slotd class pl))
495 (slot-value class 'direct-slots)))
496 (if direct-default-initargs-p
497 (setf (plist-value class 'direct-default-initargs)
498 direct-default-initargs)
499 (setq direct-default-initargs
500 (plist-value class 'direct-default-initargs)))
501 (setf (plist-value class 'class-slot-cells)
502 ;; The below initializes shared slots from direct initforms,
503 ;; but one might inherit initforms from superclasses
504 ;; (cf. UPDATE-SHARED-SLOT-VALUES).
506 (dolist (dslotd direct-slots)
507 (when (eq :class (slot-definition-allocation dslotd))
508 (let ((initfunction (slot-definition-initfunction dslotd)))
509 (push (cons (slot-definition-name dslotd)
511 (funcall initfunction)
515 (setq predicate-name (if predicate-name-p
516 (setf (slot-value class 'predicate-name)
517 (car predicate-name))
518 (or (slot-value class 'predicate-name)
519 (setf (slot-value class 'predicate-name)
520 (make-class-predicate-name (class-name
522 (add-direct-subclasses class direct-superclasses)
523 (make-class-predicate class predicate-name)
524 (update-class class nil)
525 (do* ((slots (slot-value class 'slots) (cdr slots))
527 ((null slots) (when dupes
529 ;; FIXME: the indentation request ("~4I")
530 ;; below appears not to do anything. Finding
531 ;; out why would be nice. -- CSR, 2003-04-24
532 "~@<slot names with the same SYMBOL-NAME but ~
533 different SYMBOL-PACKAGE (possible package problem) ~
534 for class ~S:~@:_~4I~<~@{~S~^~:@_~}~:>~@:>"
537 (let* ((slot (car slots))
538 (oslots (remove (slot-definition-name slot) (cdr slots)
539 :test-not #'string= :key #'slot-definition-name)))
541 (pushnew (cons (slot-definition-name slot)
542 (mapcar #'slot-definition-name oslots))
544 :test #'string= :key #'car))))
545 (add-slot-accessors class direct-slots)
546 (make-preliminary-layout class))
548 (defmethod shared-initialize :after ((class forward-referenced-class)
549 slot-names &key &allow-other-keys)
550 (declare (ignore slot-names))
551 (make-preliminary-layout class))
553 (defvar *allow-forward-referenced-classes-in-cpl-p* nil)
555 ;;; Give CLASS a preliminary layout if it doesn't have one already, to
556 ;;; make it known to the type system.
557 (defun make-preliminary-layout (class)
558 (flet ((compute-preliminary-cpl (root)
559 (let ((*allow-forward-referenced-classes-in-cpl-p* t))
560 (compute-class-precedence-list root))))
561 (unless (class-finalized-p class)
562 (let ((name (class-name class)))
563 (setf (find-class name) class)
564 ;; KLUDGE: This is fairly horrible. We need to make a
565 ;; full-fledged CLASSOID here, not just tell the compiler that
566 ;; some class is forthcoming, because there are legitimate
567 ;; questions one can ask of the type system, implemented in
568 ;; terms of CLASSOIDs, involving forward-referenced classes. So.
569 (when (and (eq *boot-state* 'complete)
570 (null (find-classoid name nil)))
571 (setf (find-classoid name)
572 (make-standard-classoid :name name)))
573 (set-class-type-translation class name)
574 (let ((layout (make-wrapper 0 class))
575 (classoid (find-classoid name)))
576 (setf (layout-classoid layout) classoid)
577 (setf (classoid-pcl-class classoid) class)
578 (setf (slot-value class 'wrapper) layout)
579 (let ((cpl (compute-preliminary-cpl class)))
580 (setf (layout-inherits layout)
581 (order-layout-inherits
582 (map 'simple-vector #'class-wrapper
583 (reverse (rest cpl))))))
584 (register-layout layout :invalidate t)
585 (setf (classoid-layout classoid) layout)
586 (mapc #'make-preliminary-layout (class-direct-subclasses class)))))))
589 (defmethod shared-initialize :before ((class class) slot-names &key name)
590 (declare (ignore slot-names name))
591 ;; FIXME: Could this just be CLASS instead of `(CLASS ,CLASS)? If not,
592 ;; why not? (See also similar expression in !BOOTSTRAP-INITIALIZE-CLASS.)
593 (setf (slot-value class 'type) `(class ,class))
594 (setf (slot-value class 'class-eq-specializer)
595 (make-instance 'class-eq-specializer :class class)))
597 (defmethod reinitialize-instance :before ((class slot-class) &key)
598 (remove-direct-subclasses class (class-direct-superclasses class))
599 (remove-slot-accessors class (class-direct-slots class)))
601 (defmethod reinitialize-instance :after ((class slot-class)
604 (map-dependents class
606 (apply #'update-dependent class dependent initargs))))
608 (defmethod shared-initialize :after ((class condition-class) slot-names
609 &key direct-slots direct-superclasses)
610 (declare (ignore slot-names))
611 (let ((classoid (find-classoid (class-name class))))
612 (with-slots (wrapper class-precedence-list prototype predicate-name
613 (direct-supers direct-superclasses))
615 (setf (slot-value class 'direct-slots)
616 (mapcar (lambda (pl) (make-direct-slotd class pl))
618 (setf (slot-value class 'finalized-p) t)
619 (setf (classoid-pcl-class classoid) class)
620 (setq direct-supers direct-superclasses)
621 (setq wrapper (classoid-layout classoid))
622 (setq class-precedence-list (compute-class-precedence-list class))
623 (setq prototype (make-condition (class-name class)))
624 (add-direct-subclasses class direct-superclasses)
625 (setq predicate-name (make-class-predicate-name (class-name class)))
626 (make-class-predicate class predicate-name)
627 (setf (slot-value class 'slots) (compute-slots class))))
628 ;; Comment from Gerd's PCL, 2003-05-15:
630 ;; We don't ADD-SLOT-ACCESSORS here because we don't want to
631 ;; override condition accessors with generic functions. We do this
633 (update-pv-table-cache-info class))
635 (defmethod direct-slot-definition-class ((class condition-class)
637 (declare (ignore initargs))
638 (find-class 'condition-direct-slot-definition))
640 (defmethod effective-slot-definition-class ((class condition-class)
642 (declare (ignore initargs))
643 (find-class 'condition-effective-slot-definition))
645 (defmethod finalize-inheritance ((class condition-class))
646 (aver (slot-value class 'finalized-p))
649 (defmethod compute-effective-slot-definition
650 ((class condition-class) slot-name dslotds)
651 (let ((slotd (call-next-method)))
652 (setf (slot-definition-reader-function slotd)
654 (handler-case (condition-reader-function x slot-name)
655 ;; FIXME: FIND-SLOT-DEFAULT throws an error if the slot
656 ;; is unbound; maybe it should be a CELL-ERROR of some
658 (error () (slot-unbound class x slot-name)))))
659 (setf (slot-definition-writer-function slotd)
661 (condition-writer-function x v slot-name)))
662 (setf (slot-definition-boundp-function slotd)
664 (multiple-value-bind (v c)
665 (ignore-errors (condition-reader-function x slot-name))
670 (defmethod compute-slots ((class condition-class))
671 (mapcan (lambda (superclass)
672 (mapcar (lambda (dslotd)
673 (compute-effective-slot-definition
674 class (slot-definition-name dslotd) (list dslotd)))
675 (class-direct-slots superclass)))
676 (reverse (slot-value class 'class-precedence-list))))
678 (defmethod compute-slots :around ((class condition-class))
679 (let ((eslotds (call-next-method)))
680 (mapc #'initialize-internal-slot-functions eslotds)
683 (defmethod shared-initialize :after
684 ((slotd structure-slot-definition) slot-names &key
685 (allocation :instance) allocation-class)
686 (declare (ignore slot-names allocation-class))
687 (unless (eq allocation :instance)
688 (error "Structure slots must have :INSTANCE allocation.")))
690 (defun make-structure-class-defstruct-form (name direct-slots include)
691 (let* ((conc-name (intern (format nil "~S structure class " name)))
692 (constructor (intern (format nil "~Aconstructor" conc-name)))
693 (defstruct `(defstruct (,name
695 `((:include ,(class-name include))))
697 (:conc-name ,conc-name)
698 (:constructor ,constructor ())
700 ,@(mapcar (lambda (slot)
701 `(,(slot-definition-name slot)
704 (reader-names (mapcar (lambda (slotd)
705 (list 'slot-accessor name
706 (slot-definition-name slotd)
709 (writer-names (mapcar (lambda (slotd)
710 (list 'slot-accessor name
711 (slot-definition-name slotd)
715 (mapcar (lambda (slotd reader-name)
717 (slot-definition-defstruct-accessor-symbol
719 `(defun ,reader-name (obj)
720 (declare (type ,name obj))
722 direct-slots reader-names))
724 (mapcar (lambda (slotd writer-name)
726 (slot-definition-defstruct-accessor-symbol
728 `(defun ,writer-name (nv obj)
729 (declare (type ,name obj))
730 (setf (,accessor obj) nv))))
731 direct-slots writer-names))
735 ,@readers-init ,@writers-init
737 (values defstruct-form constructor reader-names writer-names)))
739 (defun make-defstruct-allocation-function (class)
740 (let ((dd (get-structure-dd (class-name class))))
742 (let ((instance (%make-instance (dd-length dd)))
743 (raw-index (dd-raw-index dd)))
744 (setf (%instance-layout instance)
745 (sb-kernel::compiler-layout-or-lose (dd-name dd)))
747 (setf (%instance-ref instance raw-index)
748 (make-array (dd-raw-length dd)
749 :element-type '(unsigned-byte 32))))
752 (defmethod shared-initialize :after
753 ((class structure-class)
755 &key (direct-superclasses nil direct-superclasses-p)
756 (direct-slots nil direct-slots-p)
757 direct-default-initargs
758 (predicate-name nil predicate-name-p))
759 (declare (ignore slot-names direct-default-initargs))
760 (if direct-superclasses-p
761 (setf (slot-value class 'direct-superclasses)
762 (or direct-superclasses
763 (setq direct-superclasses
764 (and (not (eq (class-name class) 'structure-object))
765 (list *the-class-structure-object*)))))
766 (setq direct-superclasses (slot-value class 'direct-superclasses)))
767 (let* ((name (class-name class))
768 (from-defclass-p (slot-value class 'from-defclass-p))
769 (defstruct-p (or from-defclass-p (not (structure-type-p name)))))
771 (setf (slot-value class 'direct-slots)
775 (let* ((slot-name (getf pl :name))
778 "~S structure class ~A"
780 (accessor (intern acc-name)))
781 (setq pl (list* :defstruct-accessor-symbol
783 (make-direct-slotd class pl))
785 (setq direct-slots (slot-value class 'direct-slots)))
787 (let ((include (car (slot-value class 'direct-superclasses))))
788 (multiple-value-bind (defstruct-form constructor reader-names writer-names)
789 (make-structure-class-defstruct-form name direct-slots include)
790 (unless (structure-type-p name) (eval defstruct-form))
791 (mapc (lambda (dslotd reader-name writer-name)
792 (let* ((reader (gdefinition reader-name))
793 (writer (when (gboundp writer-name)
794 (gdefinition writer-name))))
795 (setf (slot-value dslotd 'internal-reader-function)
797 (setf (slot-value dslotd 'internal-writer-function)
799 direct-slots reader-names writer-names)
800 (setf (slot-value class 'defstruct-form) defstruct-form)
801 (setf (slot-value class 'defstruct-constructor) constructor)))
802 (setf (slot-value class 'defstruct-constructor)
803 (make-defstruct-allocation-function class)))
804 (add-direct-subclasses class direct-superclasses)
805 (setf (slot-value class 'class-precedence-list)
806 (compute-class-precedence-list class))
807 (setf (slot-value class 'slots) (compute-slots class))
808 (let ((lclass (find-classoid (class-name class))))
809 (setf (classoid-pcl-class lclass) class)
810 (setf (slot-value class 'wrapper) (classoid-layout lclass)))
811 (setf (slot-value class 'finalized-p) t)
812 (update-pv-table-cache-info class)
813 (setq predicate-name (if predicate-name-p
814 (setf (slot-value class 'predicate-name)
815 (car predicate-name))
816 (or (slot-value class 'predicate-name)
817 (setf (slot-value class 'predicate-name)
818 (make-class-predicate-name
819 (class-name class))))))
820 (make-class-predicate class predicate-name)
821 (add-slot-accessors class direct-slots)))
823 (defmethod direct-slot-definition-class ((class structure-class) &rest initargs)
824 (declare (ignore initargs))
825 (find-class 'structure-direct-slot-definition))
827 (defmethod finalize-inheritance ((class structure-class))
828 nil) ; always finalized
830 (defun add-slot-accessors (class dslotds)
831 (fix-slot-accessors class dslotds 'add))
833 (defun remove-slot-accessors (class dslotds)
834 (fix-slot-accessors class dslotds 'remove))
836 (defun fix-slot-accessors (class dslotds add/remove)
837 (flet ((fix (gfspec name r/w)
838 (let ((gf (ensure-generic-function gfspec)))
840 (r (if (eq add/remove 'add)
841 (add-reader-method class gf name)
842 (remove-reader-method class gf)))
843 (w (if (eq add/remove 'add)
844 (add-writer-method class gf name)
845 (remove-writer-method class gf)))))))
846 (dolist (dslotd dslotds)
847 (let ((slot-name (slot-definition-name dslotd)))
848 (dolist (r (slot-definition-readers dslotd)) (fix r slot-name 'r))
849 (dolist (w (slot-definition-writers dslotd)) (fix w slot-name 'w))))))
851 (defun add-direct-subclasses (class supers)
852 (dolist (super supers)
853 (unless (memq class (class-direct-subclasses class))
854 (add-direct-subclass super class))))
856 (defun remove-direct-subclasses (class supers)
857 (let ((old (class-direct-superclasses class)))
858 (dolist (o (set-difference old supers))
859 (remove-direct-subclass o class))))
861 (defmethod finalize-inheritance ((class std-class))
862 (update-class class t))
864 (defmethod finalize-inheritance ((class forward-referenced-class))
865 ;; FIXME: should we not be thinking a bit about what kinds of error
866 ;; we're throwing? Maybe we need a clos-error type to mix in? Or
867 ;; possibly a forward-referenced-class-error, though that's
868 ;; difficult given e.g. class precedence list calculations...
870 "~@<FINALIZE-INHERITANCE was called on a forward referenced class:~
875 (defun class-has-a-forward-referenced-superclass-p (class)
876 (or (forward-referenced-class-p class)
877 (some #'class-has-a-forward-referenced-superclass-p
878 (class-direct-superclasses class))))
880 ;;; This is called by :after shared-initialize whenever a class is initialized
881 ;;; or reinitialized. The class may or may not be finalized.
882 (defun update-class (class finalizep)
883 ;; Comment from Gerd Moellmann:
885 ;; Note that we can't simply delay the finalization when CLASS has
886 ;; no forward referenced superclasses because that causes bootstrap
888 (when (and (not finalizep)
889 (not (class-finalized-p class))
890 (not (class-has-a-forward-referenced-superclass-p class)))
891 (finalize-inheritance class)
892 (return-from update-class))
893 (when (or finalizep (class-finalized-p class)
894 (not (class-has-a-forward-referenced-superclass-p class)))
895 (setf (find-class (class-name class)) class)
896 (update-cpl class (compute-class-precedence-list class))
897 ;; This invocation of UPDATE-SLOTS, in practice, finalizes the
898 ;; class. The hoops above are to ensure that FINALIZE-INHERITANCE
899 ;; is called at finalization, so that MOP programmers can hook
900 ;; into the system as described in "Class Finalization Protocol"
901 ;; (section 5.5.2 of AMOP).
902 (update-slots class (compute-slots class))
903 (update-gfs-of-class class)
904 (update-inits class (compute-default-initargs class))
905 (update-shared-slot-values class)
906 (update-ctors 'finalize-inheritance :class class))
908 (dolist (sub (class-direct-subclasses class)) (update-class sub nil))))
910 (defun update-shared-slot-values (class)
911 (dolist (slot (class-slots class))
912 (when (eq (slot-definition-allocation slot) :class)
913 (let ((cell (assq (slot-definition-name slot) (class-slot-cells class))))
915 (let ((initfn (slot-definition-initfunction slot)))
917 (setf (cdr cell) (funcall initfn)))))))))
919 (defun update-cpl (class cpl)
920 (if (class-finalized-p class)
921 (unless (and (equal (class-precedence-list class) cpl)
923 (when (position :class (class-direct-slots c)
924 :key #'slot-definition-allocation)
926 ;; comment from the old CMU CL sources:
927 ;; Need to have the cpl setup before update-lisp-class-layout
928 ;; is called on CMU CL.
929 (setf (slot-value class 'class-precedence-list) cpl)
930 (force-cache-flushes class))
931 (setf (slot-value class 'class-precedence-list) cpl))
932 (update-class-can-precede-p cpl))
934 (defun update-class-can-precede-p (cpl)
936 (let ((first (car cpl)))
937 (dolist (c (cdr cpl))
938 (pushnew c (slot-value first 'can-precede-list))))
939 (update-class-can-precede-p (cdr cpl))))
941 (defun class-can-precede-p (class1 class2)
942 (member class2 (class-can-precede-list class1)))
944 (defun update-slots (class eslotds)
945 (let ((instance-slots ())
947 (dolist (eslotd eslotds)
948 (let ((alloc (slot-definition-allocation eslotd)))
950 (:instance (push eslotd instance-slots))
951 (:class (push eslotd class-slots)))))
953 ;; If there is a change in the shape of the instances then the
954 ;; old class is now obsolete.
955 (let* ((nlayout (mapcar #'slot-definition-name
956 (sort instance-slots #'<
957 :key #'slot-definition-location)))
958 (nslots (length nlayout))
959 (nwrapper-class-slots (compute-class-slots class-slots))
960 (owrapper (when (class-finalized-p class)
961 (class-wrapper class)))
962 (olayout (when owrapper
963 (wrapper-instance-slots-layout owrapper)))
964 (owrapper-class-slots (and owrapper (wrapper-class-slots owrapper)))
966 (cond ((null owrapper)
967 (make-wrapper nslots class))
968 ((and (equal nlayout olayout)
970 (loop for o in owrapper-class-slots
971 for n in nwrapper-class-slots
972 do (unless (eq (car o) (car n)) (return t)))))
975 ;; This will initialize the new wrapper to have the
976 ;; same state as the old wrapper. We will then have
977 ;; to change that. This may seem like wasted work
978 ;; (and it is), but the spec requires that we call
979 ;; MAKE-INSTANCES-OBSOLETE.
980 (make-instances-obsolete class)
981 (class-wrapper class)))))
983 (with-slots (wrapper slots) class
984 (update-lisp-class-layout class nwrapper)
986 (wrapper-instance-slots-layout nwrapper) nlayout
987 (wrapper-class-slots nwrapper) nwrapper-class-slots
988 (wrapper-no-of-instance-slots nwrapper) nslots
990 (setf (slot-value class 'finalized-p) t)
991 (unless (eq owrapper nwrapper)
992 (update-pv-table-cache-info class)
993 (maybe-update-standard-class-locations class)))))
995 (defun compute-class-slots (eslotds)
997 (dolist (eslotd eslotds)
998 (push (assoc (slot-definition-name eslotd)
999 (class-slot-cells (slot-definition-class eslotd)))
1001 (nreverse collect)))
1003 (defun update-gfs-of-class (class)
1004 (when (and (class-finalized-p class)
1005 (let ((cpl (class-precedence-list class)))
1006 (or (member *the-class-slot-class* cpl)
1007 (member *the-class-standard-effective-slot-definition*
1009 (let ((gf-table (make-hash-table :test 'eq)))
1010 (labels ((collect-gfs (class)
1011 (dolist (gf (specializer-direct-generic-functions class))
1012 (setf (gethash gf gf-table) t))
1013 (mapc #'collect-gfs (class-direct-superclasses class))))
1015 (maphash (lambda (gf ignore)
1016 (declare (ignore ignore))
1017 (update-gf-dfun class gf))
1020 (defun update-inits (class inits)
1021 (setf (plist-value class 'default-initargs) inits))
1023 (defmethod compute-default-initargs ((class slot-class))
1024 (let ((initargs (loop for c in (class-precedence-list class)
1025 append (class-direct-default-initargs c))))
1026 (delete-duplicates initargs :test #'eq :key #'car :from-end t)))
1028 ;;;; protocols for constructing direct and effective slot definitions
1030 (defmethod direct-slot-definition-class ((class std-class) &rest initargs)
1031 (declare (ignore initargs))
1032 (find-class 'standard-direct-slot-definition))
1034 (defun make-direct-slotd (class initargs)
1035 (let ((initargs (list* :class class initargs)))
1036 (apply #'make-instance
1037 (apply #'direct-slot-definition-class class initargs)
1040 (defmethod compute-slots ((class std-class))
1041 ;; As specified, we must call COMPUTE-EFFECTIVE-SLOT-DEFINITION once
1042 ;; for each different slot name we find in our superclasses. Each
1043 ;; call receives the class and a list of the dslotds with that name.
1044 ;; The list is in most-specific-first order.
1045 (let ((name-dslotds-alist ()))
1046 (dolist (c (class-precedence-list class))
1047 (dolist (slot (class-direct-slots c))
1048 (let* ((name (slot-definition-name slot))
1049 (entry (assq name name-dslotds-alist)))
1051 (push slot (cdr entry))
1052 (push (list name slot) name-dslotds-alist)))))
1053 (mapcar (lambda (direct)
1054 (compute-effective-slot-definition class
1056 (nreverse (cdr direct))))
1057 name-dslotds-alist)))
1059 (defmethod compute-slots ((class standard-class))
1062 (defmethod compute-slots :around ((class standard-class))
1063 (let ((eslotds (call-next-method))
1065 (dolist (eslotd eslotds eslotds)
1066 (setf (slot-definition-location eslotd)
1067 (ecase (slot-definition-allocation eslotd)
1071 (let* ((name (slot-definition-name eslotd))
1072 (from-class (slot-definition-allocation-class eslotd))
1073 (cell (assq name (class-slot-cells from-class))))
1076 (initialize-internal-slot-functions eslotd))))
1078 (defmethod compute-slots ((class funcallable-standard-class))
1081 (defmethod compute-slots :around ((class funcallable-standard-class))
1082 (labels ((instance-slot-names (slotds)
1084 (dolist (slotd slotds (nreverse collect))
1085 (when (eq (slot-definition-allocation slotd) :instance)
1086 (push (slot-definition-name slotd) collect)))))
1087 ;; This sorts slots so that slots of classes later in the CPL
1088 ;; come before slots of other classes. This is crucial for
1089 ;; funcallable instances because it ensures that the slots of
1090 ;; FUNCALLABLE-STANDARD-OBJECT, which includes the slots of
1091 ;; KERNEL:FUNCALLABLE-INSTANCE, come first, which in turn
1092 ;; makes it possible to treat FUNCALLABLE-STANDARD-OBJECT as
1093 ;; a funcallable instance.
1094 (compute-layout (eslotds)
1096 (names (instance-slot-names eslotds)))
1098 (reverse (class-precedence-list class))
1099 (nreverse (nconc names first)))
1100 (dolist (ss (class-slots class))
1101 (let ((name (slot-definition-name ss)))
1102 (when (member name names)
1104 (setq names (delete name names)))))))))
1105 (let ((all-slotds (call-next-method))
1108 (dolist (slotd all-slotds)
1109 (ecase (slot-definition-allocation slotd)
1110 (:instance (push slotd instance-slots))
1111 (:class (push slotd class-slots))))
1112 (let ((layout (compute-layout instance-slots)))
1113 (dolist (slotd instance-slots)
1114 (setf (slot-definition-location slotd)
1115 (position (slot-definition-name slotd) layout))
1116 (initialize-internal-slot-functions slotd)))
1117 (dolist (slotd class-slots)
1118 (let ((name (slot-definition-name slotd))
1119 (from-class (slot-definition-allocation-class slotd)))
1120 (setf (slot-definition-location slotd)
1121 (assoc name (class-slot-cells from-class)))
1122 (aver (consp (slot-definition-location slotd)))
1123 (initialize-internal-slot-functions slotd)))
1126 (defmethod compute-slots ((class structure-class))
1127 (mapcan (lambda (superclass)
1128 (mapcar (lambda (dslotd)
1129 (compute-effective-slot-definition
1131 (slot-definition-name dslotd)
1133 (class-direct-slots superclass)))
1134 (reverse (slot-value class 'class-precedence-list))))
1136 (defmethod compute-slots :around ((class structure-class))
1137 (let ((eslotds (call-next-method)))
1138 (mapc #'initialize-internal-slot-functions eslotds)
1141 (defmethod compute-effective-slot-definition ((class slot-class) name dslotds)
1142 (declare (ignore name))
1143 (let* ((initargs (compute-effective-slot-definition-initargs class dslotds))
1144 (class (apply #'effective-slot-definition-class class initargs)))
1145 (apply #'make-instance class initargs)))
1147 (defmethod effective-slot-definition-class ((class std-class) &rest initargs)
1148 (declare (ignore initargs))
1149 (find-class 'standard-effective-slot-definition))
1151 (defmethod effective-slot-definition-class ((class structure-class) &rest initargs)
1152 (declare (ignore initargs))
1153 (find-class 'structure-effective-slot-definition))
1155 (defmethod compute-effective-slot-definition-initargs
1156 ((class slot-class) direct-slotds)
1162 (allocation-class nil)
1168 (dolist (slotd direct-slotds)
1171 (setq name (slot-definition-name slotd)
1174 (when (slot-definition-initfunction slotd)
1175 (setq initform (slot-definition-initform slotd)
1176 initfunction (slot-definition-initfunction slotd)
1179 (setq allocation (slot-definition-allocation slotd)
1180 allocation-class (slot-definition-class slotd)
1182 (setq initargs (append (slot-definition-initargs slotd) initargs))
1183 (let ((slotd-type (slot-definition-type slotd)))
1184 (setq type (cond ((eq type t) slotd-type)
1185 ((*subtypep type slotd-type) type)
1186 (t `(and ,type ,slotd-type)))))))
1189 :initfunction initfunction
1191 :allocation allocation
1192 :allocation-class allocation-class
1196 (defmethod compute-effective-slot-definition-initargs :around
1197 ((class structure-class) direct-slotds)
1198 (let ((slotd (car direct-slotds)))
1199 (list* :defstruct-accessor-symbol
1200 (slot-definition-defstruct-accessor-symbol slotd)
1201 :internal-reader-function
1202 (slot-definition-internal-reader-function slotd)
1203 :internal-writer-function
1204 (slot-definition-internal-writer-function slotd)
1205 (call-next-method))))
1207 ;;; NOTE: For bootstrapping considerations, these can't use MAKE-INSTANCE
1208 ;;; to make the method object. They have to use make-a-method which
1209 ;;; is a specially bootstrapped mechanism for making standard methods.
1210 (defmethod reader-method-class ((class slot-class) direct-slot &rest initargs)
1211 (declare (ignore direct-slot initargs))
1212 (find-class 'standard-reader-method))
1214 (defmethod add-reader-method ((class slot-class) generic-function slot-name)
1215 (add-method generic-function
1216 (make-a-method 'standard-reader-method
1218 (list (or (class-name class) 'object))
1220 (make-reader-method-function class slot-name)
1221 "automatically generated reader method"
1224 (defmethod writer-method-class ((class slot-class) direct-slot &rest initargs)
1225 (declare (ignore direct-slot initargs))
1226 (find-class 'standard-writer-method))
1228 (defmethod add-writer-method ((class slot-class) generic-function slot-name)
1229 (add-method generic-function
1230 (make-a-method 'standard-writer-method
1232 (list 'new-value (or (class-name class) 'object))
1233 (list *the-class-t* class)
1234 (make-writer-method-function class slot-name)
1235 "automatically generated writer method"
1238 (defmethod add-boundp-method ((class slot-class) generic-function slot-name)
1239 (add-method generic-function
1240 (make-a-method 'standard-boundp-method
1242 (list (or (class-name class) 'object))
1244 (make-boundp-method-function class slot-name)
1245 "automatically generated boundp method"
1248 (defmethod remove-reader-method ((class slot-class) generic-function)
1249 (let ((method (get-method generic-function () (list class) nil)))
1250 (when method (remove-method generic-function method))))
1252 (defmethod remove-writer-method ((class slot-class) generic-function)
1254 (get-method generic-function () (list *the-class-t* class) nil)))
1255 (when method (remove-method generic-function method))))
1257 (defmethod remove-boundp-method ((class slot-class) generic-function)
1258 (let ((method (get-method generic-function () (list class) nil)))
1259 (when method (remove-method generic-function method))))
1261 ;;; MAKE-READER-METHOD-FUNCTION and MAKE-WRITE-METHOD function are NOT
1262 ;;; part of the standard protocol. They are however useful, PCL makes
1263 ;;; use of them internally and documents them for PCL users.
1265 ;;; *** This needs work to make type testing by the writer functions which
1266 ;;; *** do type testing faster. The idea would be to have one constructor
1267 ;;; *** for each possible type test.
1269 ;;; *** There is a subtle bug here which is going to have to be fixed.
1270 ;;; *** Namely, the simplistic use of the template has to be fixed. We
1271 ;;; *** have to give the OPTIMIZE-SLOT-VALUE method the user might have
1272 ;;; *** defined for this metaclass a chance to run.
1274 (defmethod make-reader-method-function ((class slot-class) slot-name)
1275 (make-std-reader-method-function (class-name class) slot-name))
1277 (defmethod make-writer-method-function ((class slot-class) slot-name)
1278 (make-std-writer-method-function (class-name class) slot-name))
1280 (defmethod make-boundp-method-function ((class slot-class) slot-name)
1281 (make-std-boundp-method-function (class-name class) slot-name))
1283 (defmethod compatible-meta-class-change-p (class proto-new-class)
1284 (eq (class-of class) (class-of proto-new-class)))
1286 (defmethod validate-superclass ((class class) (new-super class))
1287 (or (eq new-super *the-class-t*)
1288 (eq (class-of class) (class-of new-super))))
1290 (defmethod validate-superclass ((class standard-class) (new-super std-class))
1291 (let ((new-super-meta-class (class-of new-super)))
1292 (or (eq new-super-meta-class *the-class-std-class*)
1293 (eq (class-of class) new-super-meta-class))))
1295 ;;; What this does depends on which of the four possible values of
1296 ;;; LAYOUT-INVALID the PCL wrapper has; the simplest case is when it
1297 ;;; is (:FLUSH <wrapper>) or (:OBSOLETE <wrapper>), when there is
1298 ;;; nothing to do, as the new wrapper has already been created. If
1299 ;;; LAYOUT-INVALID returns NIL, then we invalidate it (setting it to
1300 ;;; (:FLUSH <wrapper>); UPDATE-SLOTS later gets to choose whether or
1301 ;;; not to "upgrade" this to (:OBSOLETE <wrapper>).
1303 ;;; This leaves the case where LAYOUT-INVALID returns T, which happens
1304 ;;; when REGISTER-LAYOUT has invalidated a superclass of CLASS (which
1305 ;;; invalidated all the subclasses in SB-KERNEL land). Again, here we
1306 ;;; must flush the caches and allow UPDATE-SLOTS to decide whether to
1307 ;;; obsolete the wrapper.
1309 ;;; FIXME: either here or in INVALID-WRAPPER-P looks like a good place
1310 ;;; for (AVER (NOT (EQ (LAYOUT-INVALID OWRAPPER)
1311 ;;; :UNINITIALIZED)))
1313 ;;; Thanks to Gerd Moellmann for the explanation. -- CSR, 2002-10-29
1314 (defun force-cache-flushes (class)
1315 (let* ((owrapper (class-wrapper class)))
1316 ;; We only need to do something if the wrapper is still valid. If
1317 ;; the wrapper isn't valid, state will be FLUSH or OBSOLETE, and
1318 ;; both of those will already be doing what we want. In
1319 ;; particular, we must be sure we never change an OBSOLETE into a
1320 ;; FLUSH since OBSOLETE means do what FLUSH does and then some.
1321 (when (or (not (invalid-wrapper-p owrapper))
1322 ;; KLUDGE: despite the observations above, this remains
1323 ;; a violation of locality or what might be considered
1324 ;; good style. There has to be a better way! -- CSR,
1326 (eq (layout-invalid owrapper) t))
1327 (let ((nwrapper (make-wrapper (wrapper-no-of-instance-slots owrapper)
1329 (setf (wrapper-instance-slots-layout nwrapper)
1330 (wrapper-instance-slots-layout owrapper))
1331 (setf (wrapper-class-slots nwrapper)
1332 (wrapper-class-slots owrapper))
1334 (update-lisp-class-layout class nwrapper)
1335 (setf (slot-value class 'wrapper) nwrapper)
1336 (invalidate-wrapper owrapper :flush nwrapper))))))
1338 (defun flush-cache-trap (owrapper nwrapper instance)
1339 (declare (ignore owrapper))
1340 (set-wrapper instance nwrapper))
1342 ;;; MAKE-INSTANCES-OBSOLETE can be called by user code. It will cause
1343 ;;; the next access to the instance (as defined in 88-002R) to trap
1344 ;;; through the UPDATE-INSTANCE-FOR-REDEFINED-CLASS mechanism.
1345 (defmethod make-instances-obsolete ((class std-class))
1346 (let* ((owrapper (class-wrapper class))
1347 (nwrapper (make-wrapper (wrapper-no-of-instance-slots owrapper)
1349 (setf (wrapper-instance-slots-layout nwrapper)
1350 (wrapper-instance-slots-layout owrapper))
1351 (setf (wrapper-class-slots nwrapper)
1352 (wrapper-class-slots owrapper))
1354 (update-lisp-class-layout class nwrapper)
1355 (setf (slot-value class 'wrapper) nwrapper)
1356 (invalidate-wrapper owrapper :obsolete nwrapper)
1359 (defmethod make-instances-obsolete ((class symbol))
1360 (make-instances-obsolete (find-class class)))
1362 ;;; OBSOLETE-INSTANCE-TRAP is the internal trap that is called when we
1363 ;;; see an obsolete instance. The times when it is called are:
1364 ;;; - when the instance is involved in method lookup
1365 ;;; - when attempting to access a slot of an instance
1367 ;;; It is not called by class-of, wrapper-of, or any of the low-level
1368 ;;; instance access macros.
1370 ;;; Of course these times when it is called are an internal
1371 ;;; implementation detail of PCL and are not part of the documented
1372 ;;; description of when the obsolete instance update happens. The
1373 ;;; documented description is as it appears in 88-002R.
1375 ;;; This has to return the new wrapper, so it counts on all the
1376 ;;; methods on obsolete-instance-trap-internal to return the new
1377 ;;; wrapper. It also does a little internal error checking to make
1378 ;;; sure that the traps are only happening when they should, and that
1379 ;;; the trap methods are computing appropriate new wrappers.
1381 ;;; OBSOLETE-INSTANCE-TRAP might be called on structure instances
1382 ;;; after a structure is redefined. In most cases,
1383 ;;; OBSOLETE-INSTANCE-TRAP will not be able to fix the old instance,
1384 ;;; so it must signal an error. The hard part of this is that the
1385 ;;; error system and debugger might cause OBSOLETE-INSTANCE-TRAP to be
1386 ;;; called again, so in that case, we have to return some reasonable
1387 ;;; wrapper, instead.
1389 (defvar *in-obsolete-instance-trap* nil)
1390 (defvar *the-wrapper-of-structure-object*
1391 (class-wrapper (find-class 'structure-object)))
1393 (define-condition obsolete-structure (error)
1394 ((datum :reader obsolete-structure-datum :initarg :datum))
1396 (lambda (condition stream)
1397 ;; Don't try to print the structure, since it probably won't work.
1399 "~@<obsolete structure error for a structure of type ~2I~_~S~:>"
1400 (type-of (obsolete-structure-datum condition))))))
1402 (defun obsolete-instance-trap (owrapper nwrapper instance)
1403 (if (not (pcl-instance-p instance))
1404 (if *in-obsolete-instance-trap*
1405 *the-wrapper-of-structure-object*
1406 (let ((*in-obsolete-instance-trap* t))
1407 (error 'obsolete-structure :datum instance)))
1408 (let* ((class (wrapper-class* nwrapper))
1409 (copy (allocate-instance class)) ;??? allocate-instance ???
1410 (olayout (wrapper-instance-slots-layout owrapper))
1411 (nlayout (wrapper-instance-slots-layout nwrapper))
1412 (oslots (get-slots instance))
1413 (nslots (get-slots copy))
1414 (oclass-slots (wrapper-class-slots owrapper))
1418 ;; local --> local transfer
1419 ;; local --> shared discard
1420 ;; local --> -- discard
1421 ;; shared --> local transfer
1422 ;; shared --> shared discard
1423 ;; shared --> -- discard
1427 ;; Go through all the old local slots.
1429 (dolist (name olayout)
1430 (let ((npos (posq name nlayout)))
1432 (setf (clos-slots-ref nslots npos)
1433 (clos-slots-ref oslots opos))
1435 (push name discarded)
1436 (unless (eq (clos-slots-ref oslots opos) +slot-unbound+)
1437 (setf (getf plist name) (clos-slots-ref oslots opos))))))
1440 ;; Go through all the old shared slots.
1441 (dolist (oclass-slot-and-val oclass-slots)
1442 (let ((name (car oclass-slot-and-val))
1443 (val (cdr oclass-slot-and-val)))
1444 (let ((npos (posq name nlayout)))
1446 (setf (clos-slots-ref nslots npos) (cdr oclass-slot-and-val))
1447 (progn (push name discarded)
1448 (unless (eq val +slot-unbound+)
1449 (setf (getf plist name) val)))))))
1451 ;; Go through all the new local slots to compute the added slots.
1452 (dolist (nlocal nlayout)
1453 (unless (or (memq nlocal olayout)
1454 (assq nlocal oclass-slots))
1455 (push nlocal added)))
1457 (swap-wrappers-and-slots instance copy)
1459 (update-instance-for-redefined-class instance
1465 (defun change-class-internal (instance new-class initargs)
1466 (let* ((old-class (class-of instance))
1467 (copy (allocate-instance new-class))
1468 (new-wrapper (get-wrapper copy))
1469 (old-wrapper (class-wrapper old-class))
1470 (old-layout (wrapper-instance-slots-layout old-wrapper))
1471 (new-layout (wrapper-instance-slots-layout new-wrapper))
1472 (old-slots (get-slots instance))
1473 (new-slots (get-slots copy))
1474 (old-class-slots (wrapper-class-slots old-wrapper)))
1476 ;; "The values of local slots specified by both the class CTO and
1477 ;; CFROM are retained. If such a local slot was unbound, it
1478 ;; remains unbound."
1479 (let ((new-position 0))
1480 (dolist (new-slot new-layout)
1481 (let ((old-position (posq new-slot old-layout)))
1483 (setf (clos-slots-ref new-slots new-position)
1484 (clos-slots-ref old-slots old-position))))
1485 (incf new-position)))
1487 ;; "The values of slots specified as shared in the class CFROM and
1488 ;; as local in the class CTO are retained."
1489 (dolist (slot-and-val old-class-slots)
1490 (let ((position (posq (car slot-and-val) new-layout)))
1492 (setf (clos-slots-ref new-slots position) (cdr slot-and-val)))))
1494 ;; Make the copy point to the old instance's storage, and make the
1495 ;; old instance point to the new storage.
1496 (swap-wrappers-and-slots instance copy)
1498 (apply #'update-instance-for-different-class copy instance initargs)
1501 (defmethod change-class ((instance standard-object)
1502 (new-class standard-class)
1504 (change-class-internal instance new-class initargs))
1506 (defmethod change-class ((instance funcallable-standard-object)
1507 (new-class funcallable-standard-class)
1509 (change-class-internal instance new-class initargs))
1511 (defmethod change-class ((instance standard-object)
1512 (new-class funcallable-standard-class)
1514 (declare (ignore initargs))
1515 (error "You can't change the class of ~S to ~S~@
1516 because it isn't already an instance with metaclass ~S."
1517 instance new-class 'standard-class))
1519 (defmethod change-class ((instance funcallable-standard-object)
1520 (new-class standard-class)
1522 (declare (ignore initargs))
1523 (error "You can't change the class of ~S to ~S~@
1524 because it isn't already an instance with metaclass ~S."
1525 instance new-class 'funcallable-standard-class))
1527 (defmethod change-class ((instance t) (new-class-name symbol) &rest initargs)
1528 (apply #'change-class instance (find-class new-class-name) initargs))
1530 ;;;; The metaclass BUILT-IN-CLASS
1532 ;;;; This metaclass is something of a weird creature. By this point, all
1533 ;;;; instances of it which will exist have been created, and no instance
1534 ;;;; is ever created by calling MAKE-INSTANCE.
1536 ;;;; But, there are other parts of the protocol we must follow and those
1537 ;;;; definitions appear here.
1539 (defmethod shared-initialize :before
1540 ((class built-in-class) slot-names &rest initargs)
1541 (declare (ignore slot-names initargs))
1542 (error "attempt to initialize or reinitialize a built in class"))
1544 (defmethod class-direct-slots ((class built-in-class)) ())
1545 (defmethod class-slots ((class built-in-class)) ())
1546 (defmethod class-direct-default-initargs ((class built-in-class)) ())
1547 (defmethod class-default-initargs ((class built-in-class)) ())
1549 (defmethod validate-superclass ((c class) (s built-in-class))
1550 (or (eq s *the-class-t*)
1551 (eq s *the-class-stream*)))
1553 ;;; Some necessary methods for FORWARD-REFERENCED-CLASS
1554 (defmethod class-direct-slots ((class forward-referenced-class)) ())
1555 (defmethod class-direct-default-initargs ((class forward-referenced-class)) ())
1556 (macrolet ((def (method)
1557 `(defmethod ,method ((class forward-referenced-class))
1558 (error "~@<~I~S was called on a forward referenced class:~2I~_~S~:>"
1560 (def class-default-initargs)
1561 (def class-precedence-list)
1564 (defmethod validate-superclass ((c slot-class)
1565 (f forward-referenced-class))
1568 (defmethod add-dependent ((metaobject dependent-update-mixin) dependent)
1569 (pushnew dependent (plist-value metaobject 'dependents)))
1571 (defmethod remove-dependent ((metaobject dependent-update-mixin) dependent)
1572 (setf (plist-value metaobject 'dependents)
1573 (delete dependent (plist-value metaobject 'dependents))))
1575 (defmethod map-dependents ((metaobject dependent-update-mixin) function)
1576 (dolist (dependent (plist-value metaobject 'dependents))
1577 (funcall function dependent)))