1 ;;;; This software is part of the SBCL system. See the README file for
4 ;;;; This software is derived from software originally released by Xerox
5 ;;;; Corporation. Copyright and release statements follow. Later modifications
6 ;;;; to the software are in the public domain and are provided with
7 ;;;; absolutely no warranty. See the COPYING and CREDITS files for more
10 ;;;; copyright information from original PCL sources:
12 ;;;; Copyright (c) 1985, 1986, 1987, 1988, 1989, 1990 Xerox Corporation.
13 ;;;; All rights reserved.
15 ;;;; Use and copying of this software and preparation of derivative works based
16 ;;;; upon this software are permitted. Any distribution of this software or
17 ;;;; derivative works must comply with all applicable United States export
20 ;;;; This software is made available AS IS, and Xerox Corporation makes no
21 ;;;; warranty about the software, its performance or its conformity to any
26 (defmethod slot-accessor-function ((slotd effective-slot-definition
) type
)
28 (reader (slot-definition-reader-function slotd
))
29 (writer (slot-definition-writer-function slotd
))
30 (boundp (slot-definition-boundp-function slotd
))))
32 (defmethod (setf slot-accessor-function
) (function
33 (slotd effective-slot-definition
)
36 (reader (setf (slot-definition-reader-function slotd
) function
))
37 (writer (setf (slot-definition-writer-function slotd
) function
))
38 (boundp (setf (slot-definition-boundp-function slotd
) function
))))
40 (defconstant +slotd-reader-function-std-p
+ 1)
41 (defconstant +slotd-writer-function-std-p
+ 2)
42 (defconstant +slotd-boundp-function-std-p
+ 4)
43 (defconstant +slotd-all-function-std-p
+ 7)
45 (defmethod slot-accessor-std-p ((slotd effective-slot-definition
) type
)
46 (let ((flags (slot-value slotd
'accessor-flags
)))
47 (declare (type fixnum flags
))
49 (eql +slotd-all-function-std-p
+ flags
)
50 (let ((mask (ecase type
51 (reader +slotd-reader-function-std-p
+)
52 (writer +slotd-writer-function-std-p
+)
53 (boundp +slotd-boundp-function-std-p
+))))
54 (declare (type fixnum mask
))
55 (not (zerop (the fixnum
(logand mask flags
))))))))
57 (defmethod (setf slot-accessor-std-p
) (value
58 (slotd effective-slot-definition
)
60 (let ((mask (ecase type
61 (reader +slotd-reader-function-std-p
+)
62 (writer +slotd-writer-function-std-p
+)
63 (boundp +slotd-boundp-function-std-p
+)))
64 (flags (slot-value slotd
'accessor-flags
)))
65 (declare (type fixnum mask flags
))
66 (setf (slot-value slotd
'accessor-flags
)
68 (the fixnum
(logior mask flags
))
69 (the fixnum
(logand (the fixnum
(lognot mask
)) flags
)))))
72 (defmethod initialize-internal-slot-functions ((slotd
73 effective-slot-definition
))
74 (let* ((name (slot-value slotd
'name
))
75 (class (slot-value slotd
'class
)))
76 (let ((table (or (gethash name
*name-
>class-
>slotd-table
*)
77 (setf (gethash name
*name-
>class-
>slotd-table
*)
78 (make-hash-table :test
'eq
:size
5)))))
79 (setf (gethash class table
) slotd
))
80 (dolist (type '(reader writer boundp
))
81 (let* ((gf-name (ecase type
82 (reader 'slot-value-using-class
)
83 (writer '(setf slot-value-using-class
))
84 (boundp 'slot-boundp-using-class
)))
85 (gf (gdefinition gf-name
)))
86 (compute-slot-accessor-info slotd type gf
)))
87 (initialize-internal-slot-gfs name
)))
89 (defmethod compute-slot-accessor-info ((slotd effective-slot-definition
)
91 (let* ((name (slot-value slotd
'name
))
92 (class (slot-value slotd
'class
))
93 (old-slotd (find-slot-definition class name
))
94 (old-std-p (and old-slotd
(slot-accessor-std-p old-slotd
'all
))))
95 (multiple-value-bind (function std-p
)
96 (if (eq *boot-state
* 'complete
)
97 (get-accessor-method-function gf type class slotd
)
98 (get-optimized-std-accessor-method-function class slotd type
))
99 (setf (slot-accessor-std-p slotd type
) std-p
)
100 (setf (slot-accessor-function slotd type
) function
))
101 (when (and old-slotd
(not (eq old-std-p
(slot-accessor-std-p slotd
'all
))))
102 (push (cons class name
) *pv-table-cache-update-info
*))))
104 (defmethod slot-definition-allocation ((slotd structure-slot-definition
))
107 (defmethod shared-initialize :after
((object documentation-mixin
)
109 &key
(documentation nil documentation-p
))
110 (declare (ignore slot-names
))
111 (when documentation-p
112 (setf (plist-value object
'documentation
) documentation
)))
114 ;;; default if DOC-TYPE doesn't match one of the specified types
115 (defmethod documentation (object doc-type
)
116 (warn "unsupported DOCUMENTATION: type ~S for object ~S"
121 ;;; default if DOC-TYPE doesn't match one of the specified types
122 (defmethod (setf documentation
) (new-value object doc-type
)
123 ;; CMU CL made this an error, but since ANSI says that even for supported
124 ;; doc types an implementation is permitted to discard docs at any time
125 ;; for any reason, this feels to me more like a warning. -- WHN 19991214
126 (warn "discarding unsupported DOCUMENTATION of type ~S for object ~S"
131 (defmethod documentation ((object documentation-mixin
) doc-type
)
132 (declare (ignore doc-type
))
133 (plist-value object
'documentation
))
135 (defmethod (setf documentation
) (new-value
136 (object documentation-mixin
)
138 (declare (ignore doc-type
))
139 (setf (plist-value object
'documentation
) new-value
))
141 (defmethod documentation ((slotd standard-slot-definition
) doc-type
)
142 (declare (ignore doc-type
))
143 (slot-value slotd
'documentation
))
145 (defmethod (setf documentation
) (new-value
146 (slotd standard-slot-definition
)
148 (declare (ignore doc-type
))
149 (setf (slot-value slotd
'documentation
) new-value
))
151 ;;;; various class accessors that are a little more complicated than can be
152 ;;;; done with automatically generated reader methods
154 (defmethod class-prototype ((class std-class
))
155 (with-slots (prototype) class
156 (or prototype
(setq prototype
(allocate-instance class
)))))
158 (defmethod class-prototype ((class structure-class
))
159 (with-slots (prototype wrapper defstruct-constructor
) class
162 (if defstruct-constructor
163 (allocate-instance class
)
164 (allocate-standard-instance wrapper
))))))
166 (defmethod class-direct-default-initargs ((class slot-class
))
167 (plist-value class
'direct-default-initargs
))
169 (defmethod class-default-initargs ((class slot-class
))
170 (plist-value class
'default-initargs
))
172 (defmethod class-slot-cells ((class std-class
))
173 (plist-value class
'class-slot-cells
))
175 ;;;; class accessors that are even a little bit more complicated than those
176 ;;;; above. These have a protocol for updating them, we must implement that
179 ;;; Maintaining the direct subclasses backpointers. The update methods are
180 ;;; here, the values are read by an automatically generated reader method.
181 (defmethod add-direct-subclass ((class class
) (subclass class
))
182 (with-slots (direct-subclasses) class
183 (pushnew subclass direct-subclasses
)
185 (defmethod remove-direct-subclass ((class class
) (subclass class
))
186 (with-slots (direct-subclasses) class
187 (setq direct-subclasses
(remove subclass direct-subclasses
))
190 ;;; Maintaining the direct-methods and direct-generic-functions backpointers.
192 ;;; There are four generic functions involved, each has one method for the
193 ;;; class case and another method for the damned EQL specializers. All of
194 ;;; these are specified methods and appear in their specified place in the
197 ;;; ADD-DIRECT-METHOD
198 ;;; REMOVE-DIRECT-METHOD
199 ;;; SPECIALIZER-DIRECT-METHODS
200 ;;; SPECIALIZER-DIRECT-GENERIC-FUNCTIONS
202 ;;; In each case, we maintain one value which is a cons. The car is the list
203 ;;; methods. The cdr is a list of the generic functions. The cdr is always
205 (defmethod add-direct-method ((specializer class
) (method method
))
206 (with-slots (direct-methods) specializer
207 (setf (car direct-methods
) (adjoin method
(car direct-methods
)) ;PUSH
208 (cdr direct-methods
) ()))
210 (defmethod remove-direct-method ((specializer class
) (method method
))
211 (with-slots (direct-methods) specializer
212 (setf (car direct-methods
) (remove method
(car direct-methods
))
213 (cdr direct-methods
) ()))
216 (defmethod specializer-direct-methods ((specializer class
))
217 (with-slots (direct-methods) specializer
218 (car direct-methods
)))
220 (defmethod specializer-direct-generic-functions ((specializer class
))
221 (with-slots (direct-methods) specializer
222 (or (cdr direct-methods
)
223 (setf (cdr direct-methods
)
225 (dolist (m (car direct-methods
))
226 ;; the old PCL code used COLLECTING-ONCE which used
227 ;; #'EQ to check for newness
228 (pushnew (method-generic-function m
) collect
:test
#'eq
))
229 (nreverse collect
))))))
231 ;;; This hash table is used to store the direct methods and direct generic
232 ;;; functions of EQL specializers. Each value in the table is the cons.
233 (defvar *eql-specializer-methods
* (make-hash-table :test
'eql
))
234 (defvar *class-eq-specializer-methods
* (make-hash-table :test
'eq
))
236 (defmethod specializer-method-table ((specializer eql-specializer
))
237 *eql-specializer-methods
*)
239 (defmethod specializer-method-table ((specializer class-eq-specializer
))
240 *class-eq-specializer-methods
*)
242 (defmethod add-direct-method ((specializer specializer-with-object
)
244 (let* ((object (specializer-object specializer
))
245 (table (specializer-method-table specializer
))
246 (entry (gethash object table
)))
249 (setf (gethash object table
)
251 (setf (car entry
) (adjoin method
(car entry
))
255 (defmethod remove-direct-method ((specializer specializer-with-object
)
257 (let* ((object (specializer-object specializer
))
258 (entry (gethash object
(specializer-method-table specializer
))))
260 (setf (car entry
) (remove method
(car entry
))
264 (defmethod specializer-direct-methods ((specializer specializer-with-object
))
265 (car (gethash (specializer-object specializer
)
266 (specializer-method-table specializer
))))
268 (defmethod specializer-direct-generic-functions ((specializer
269 specializer-with-object
))
270 (let* ((object (specializer-object specializer
))
271 (entry (gethash object
(specializer-method-table specializer
))))
276 (dolist (m (car entry
))
277 (pushnew (method-generic-function m
) collect
:test
#'eq
))
278 (nreverse collect
)))))))
280 (defun map-specializers (function)
281 (map-all-classes (lambda (class)
282 (funcall function
(class-eq-specializer class
))
283 (funcall function class
)))
284 (maphash (lambda (object methods
)
285 (declare (ignore methods
))
286 (intern-eql-specializer object
))
287 *eql-specializer-methods
*)
288 (maphash (lambda (object specl
)
289 (declare (ignore object
))
290 (funcall function specl
))
291 *eql-specializer-table
*)
294 (defun map-all-generic-functions (function)
295 (let ((all-generic-functions (make-hash-table :test
'eq
)))
296 (map-specializers (lambda (specl)
297 (dolist (gf (specializer-direct-generic-functions
299 (unless (gethash gf all-generic-functions
)
300 (setf (gethash gf all-generic-functions
) t
)
301 (funcall function gf
))))))
304 (defmethod shared-initialize :after
((specl class-eq-specializer
)
307 (declare (ignore slot-names
))
308 (setf (slot-value specl
'type
) `(class-eq ,(specializer-class specl
))))
310 (defmethod shared-initialize :after
((specl eql-specializer
) slot-names
&key
)
311 (declare (ignore slot-names
))
312 (setf (slot-value specl
'type
) `(eql ,(specializer-object specl
))))
314 (defun real-load-defclass (name metaclass-name supers slots other
)
315 (let ((res (apply #'ensure-class name
:metaclass metaclass-name
316 :direct-superclasses supers
318 :definition-source
`((defclass ,name
)
323 (setf (gdefinition 'load-defclass
) #'real-load-defclass
)
325 (defun ensure-class (name &rest all
)
326 (apply #'ensure-class-using-class
(find-class name nil
) name all
))
328 (defmethod ensure-class-using-class ((class null
) name
&rest args
&key
)
329 (multiple-value-bind (meta initargs
)
330 (ensure-class-values class args
)
331 (set-class-type-translation (class-prototype meta
) name
)
332 (setf class
(apply #'make-instance meta
:name name initargs
)
333 (find-class name
) class
)
334 (set-class-type-translation class name
)
337 (defmethod ensure-class-using-class ((class pcl-class
) name
&rest args
&key
)
338 (multiple-value-bind (meta initargs
)
339 (ensure-class-values class args
)
340 (unless (eq (class-of class
) meta
)
341 (apply #'change-class class meta initargs
))
342 (apply #'reinitialize-instance class initargs
)
343 (setf (find-class name
) class
)
344 (set-class-type-translation class name
)
347 (defmethod class-predicate-name ((class t
))
352 ((not (legal-class-name-p s
))
353 (error "~S is not a class or a legal class name." s
))
355 (or (find-class s nil
)
356 (make-instance 'forward-referenced-class
359 (defun ensure-class-values (class args
)
360 (let* ((initargs (copy-list args
))
361 (unsupplied (list 1))
362 (supplied-meta (getf initargs
:metaclass unsupplied
))
363 (supplied-supers (getf initargs
:direct-superclasses unsupplied
))
364 (supplied-slots (getf initargs
:direct-slots unsupplied
))
366 (cond ((neq supplied-meta unsupplied
)
367 (find-class supplied-meta
))
369 (forward-referenced-class-p class
))
370 *the-class-standard-class
*)
373 ;; KLUDGE: It seemed to me initially that there ought to be a way
374 ;; of collecting all the erroneous problems in one go, rather than
375 ;; this way of solving the problem of signalling the errors that
376 ;; we are required to, which stops at the first bogus input.
377 ;; However, after playing around a little, I couldn't find that
378 ;; way, so I've left it as is, but if someone does come up with a
379 ;; better way... -- CSR, 2002-09-08
380 (do ((direct-slots (getf initargs
:direct-slots
) (cdr direct-slots
)))
381 ((endp direct-slots
) nil
)
382 (destructuring-bind (slot &rest more
) direct-slots
383 (let ((slot-name (getf slot
:name
)))
384 (when (some (lambda (s) (eq slot-name
(getf s
:name
))) more
)
385 ;; FIXME: It's quite possible that we ought to define an
386 ;; SB-INT:PROGRAM-ERROR function to signal these and other
387 ;; errors throughout the codebase that are required to be
388 ;; of type PROGRAM-ERROR.
389 (error 'simple-program-error
390 :format-control
"~@<There is more than one direct slot ~
392 :format-arguments
(list slot-name
)))
393 (do ((stuff slot
(cddr stuff
)))
395 (destructuring-bind (option value
&rest more
) stuff
397 ((and (member option
'(:allocation
:type
398 :initform
:documentation
))
400 (getf more option unsupplied
))))
401 (error 'simple-program-error
402 :format-control
"~@<Duplicate slot option ~S for ~
404 :format-arguments
(list option slot-name
)))
405 ((and (eq option
:readers
)
406 (notevery #'symbolp value
))
407 (error 'simple-program-error
408 :format-control
"~@<Slot reader names for slot ~
409 named ~S must be symbols.~:>"
410 :format-arguments
(list slot-name
)))
411 ((and (eq option
:initargs
)
412 (notevery #'symbolp value
))
413 (error 'simple-program-error
414 :format-control
"~@<Slot initarg names for slot ~
415 named ~S must be symbols.~:>"
416 :format-arguments
(list slot-name
)))))))))
417 (loop for
(initarg . more
) on
(getf initargs
:direct-default-initargs
)
418 for name
= (car initarg
)
419 when
(some (lambda (a) (eq (car a
) name
)) more
)
420 do
(error 'simple-program-error
421 :format-control
"~@<Duplicate initialization argument ~
422 name ~S in :DEFAULT-INITARGS.~:>"
423 :format-arguments
(list name class
)))
425 (default-initargs 0))
426 (do ((args initargs
(cddr args
)))
430 (when (> (incf metaclass
) 1)
431 (error 'simple-program-error
432 :format-control
"~@<More than one :METACLASS ~
433 option specified.~:>")))
434 (:direct-default-initargs
435 (when (> (incf default-initargs
) 1)
436 (error 'simple-program-error
437 :format-control
"~@<More than one :DEFAULT-INITARGS ~
438 option specified.~:>"))))))
439 (remf initargs
:metaclass
)
440 (loop (unless (remf initargs
:direct-superclasses
) (return)))
441 (loop (unless (remf initargs
:direct-slots
) (return)))
445 (when (neq supplied-supers unsupplied
)
446 (list :direct-superclasses
(mapcar #'fix-super supplied-supers
)))
447 (when (neq supplied-slots unsupplied
)
448 (list :direct-slots supplied-slots
))
451 (defmethod shared-initialize :after
454 &key
(direct-superclasses nil direct-superclasses-p
)
455 (direct-slots nil direct-slots-p
)
456 (direct-default-initargs nil direct-default-initargs-p
)
457 (predicate-name nil predicate-name-p
))
458 (declare (ignore slot-names
))
459 (cond (direct-superclasses-p
460 (setq direct-superclasses
461 (or direct-superclasses
462 (list (if (funcallable-standard-class-p class
)
463 *the-class-funcallable-standard-object
*
464 *the-class-standard-object
*))))
465 (dolist (superclass direct-superclasses
)
466 (unless (validate-superclass class superclass
)
467 (error "The class ~S was specified as a~%
468 super-class of the class ~S;~%~
469 but the meta-classes ~S and~%~S are incompatible.~@
470 Define a method for ~S to avoid this error."
471 superclass class
(class-of superclass
) (class-of class
)
472 'validate-superclass
)))
473 (setf (slot-value class
'direct-superclasses
) direct-superclasses
))
475 (setq direct-superclasses
(slot-value class
'direct-superclasses
))))
478 (setf (slot-value class
'direct-slots
)
479 (mapcar (lambda (pl) (make-direct-slotd class pl
))
481 (slot-value class
'direct-slots
)))
482 (if direct-default-initargs-p
483 (setf (plist-value class
'direct-default-initargs
)
484 direct-default-initargs
)
485 (setq direct-default-initargs
486 (plist-value class
'direct-default-initargs
)))
487 (setf (plist-value class
'class-slot-cells
)
489 (dolist (dslotd direct-slots
)
490 (when (eq :class
(slot-definition-allocation dslotd
))
491 (let ((initfunction (slot-definition-initfunction dslotd
)))
492 (push (cons (slot-definition-name dslotd
)
494 (funcall initfunction
)
498 (setq predicate-name
(if predicate-name-p
499 (setf (slot-value class
'predicate-name
)
500 (car predicate-name
))
501 (or (slot-value class
'predicate-name
)
502 (setf (slot-value class
'predicate-name
)
503 (make-class-predicate-name (class-name
505 (add-direct-subclasses class direct-superclasses
)
506 (make-class-predicate class predicate-name
)
507 (update-class class nil
)
508 (add-slot-accessors class direct-slots
)
509 (make-preliminary-layout class
))
511 (defmethod shared-initialize :after
((class forward-referenced-class
)
512 slot-names
&key
&allow-other-keys
)
513 (declare (ignore slot-names
))
514 (make-preliminary-layout class
))
516 (defvar *allow-forward-referenced-classes-in-cpl-p
* nil
)
518 ;;; Give CLASS a preliminary layout if it doesn't have one already, to
519 ;;; make it known to the type system.
520 (defun make-preliminary-layout (class)
521 (flet ((compute-preliminary-cpl (root)
522 (let ((*allow-forward-referenced-classes-in-cpl-p
* t
))
523 (compute-class-precedence-list root
))))
524 (unless (class-finalized-p class
)
525 (let ((name (class-name class
)))
526 (setf (find-class name
) class
)
527 ;; KLUDGE: This is fairly horrible. We need to make a
528 ;; full-fledged CLASSOID here, not just tell the compiler that
529 ;; some class is forthcoming, because there are legitimate
530 ;; questions one can ask of the type system, implemented in
531 ;; terms of CLASSOIDs, involving forward-referenced classes. So.
532 (when (and (eq *boot-state
* 'complete
)
533 (null (find-classoid name nil
)))
534 (setf (find-classoid name
)
535 (make-standard-classoid :name name
)))
536 (set-class-type-translation class name
)
537 (let ((layout (make-wrapper 0 class
))
538 (classoid (find-classoid name
)))
539 (setf (layout-classoid layout
) classoid
)
540 (setf (classoid-pcl-class classoid
) class
)
541 (setf (slot-value class
'wrapper
) layout
)
542 (let ((cpl (compute-preliminary-cpl class
)))
543 (setf (layout-inherits layout
)
544 (order-layout-inherits
545 (map 'simple-vector
#'class-wrapper
546 (reverse (rest cpl
))))))
547 (register-layout layout
:invalidate t
)
548 (setf (classoid-layout classoid
) layout
)
549 (mapc #'make-preliminary-layout
(class-direct-subclasses class
)))))))
552 (defmethod shared-initialize :before
((class class
) slot-names
&key name
)
553 (declare (ignore slot-names name
))
554 ;; FIXME: Could this just be CLASS instead of `(CLASS ,CLASS)? If not,
555 ;; why not? (See also similar expression in !BOOTSTRAP-INITIALIZE-CLASS.)
556 (setf (slot-value class
'type
) `(class ,class
))
557 (setf (slot-value class
'class-eq-specializer
)
558 (make-instance 'class-eq-specializer
:class class
)))
560 (defmethod reinitialize-instance :before
((class slot-class
) &key
)
561 (remove-direct-subclasses class
(class-direct-superclasses class
))
562 (remove-slot-accessors class
(class-direct-slots class
)))
564 (defmethod reinitialize-instance :after
((class slot-class
)
567 (map-dependents class
569 (apply #'update-dependent class dependent initargs
))))
571 (defmethod shared-initialize :after
((class condition-class
) slot-names
572 &key direct-superclasses
)
573 (declare (ignore slot-names
))
574 (let ((classoid (find-classoid (class-name class
))))
575 (with-slots (wrapper class-precedence-list prototype predicate-name
576 (direct-supers direct-superclasses
))
578 (setf (slot-value class
'finalized-p
) t
)
579 (setf (classoid-pcl-class classoid
) class
)
580 (setq direct-supers direct-superclasses
)
581 (setq wrapper
(classoid-layout classoid
))
582 (setq class-precedence-list
(compute-class-precedence-list class
))
583 (setq prototype
(make-condition (class-name class
)))
584 (add-direct-subclasses class direct-superclasses
)
585 (setq predicate-name
(make-class-predicate-name (class-name class
)))
586 (make-class-predicate class predicate-name
))))
588 (defmethod shared-initialize :after
589 ((slotd structure-slot-definition
) slot-names
&key
590 (allocation :instance
) allocation-class
)
591 (declare (ignore slot-names allocation-class
))
592 (unless (eq allocation
:instance
)
593 (error "Structure slots must have :INSTANCE allocation.")))
595 (defun make-structure-class-defstruct-form (name direct-slots include
)
596 (let* ((conc-name (intern (format nil
"~S structure class " name
)))
597 (constructor (intern (format nil
"~Aconstructor" conc-name
)))
598 (defstruct `(defstruct (,name
600 `((:include
,(class-name include
))))
602 (:conc-name
,conc-name
)
603 (:constructor
,constructor
())
605 ,@(mapcar (lambda (slot)
606 `(,(slot-definition-name slot
)
609 (reader-names (mapcar (lambda (slotd)
610 (list 'slot-accessor name
611 (slot-definition-name slotd
)
614 (writer-names (mapcar (lambda (slotd)
615 (list 'slot-accessor name
616 (slot-definition-name slotd
)
620 (mapcar (lambda (slotd reader-name
)
622 (slot-definition-defstruct-accessor-symbol
624 `(defun ,reader-name
(obj)
625 (declare (type ,name obj
))
627 direct-slots reader-names
))
629 (mapcar (lambda (slotd writer-name
)
631 (slot-definition-defstruct-accessor-symbol
633 `(defun ,writer-name
(nv obj
)
634 (declare (type ,name obj
))
635 (setf (,accessor obj
) nv
))))
636 direct-slots writer-names
))
640 ,@readers-init
,@writers-init
642 (values defstruct-form constructor reader-names writer-names
)))
644 (defmethod shared-initialize :after
645 ((class structure-class
)
647 &key
(direct-superclasses nil direct-superclasses-p
)
648 (direct-slots nil direct-slots-p
)
649 direct-default-initargs
650 (predicate-name nil predicate-name-p
))
651 (declare (ignore slot-names direct-default-initargs
))
652 (if direct-superclasses-p
653 (setf (slot-value class
'direct-superclasses
)
654 (or direct-superclasses
655 (setq direct-superclasses
656 (and (not (eq (class-name class
) 'structure-object
))
657 (list *the-class-structure-object
*)))))
658 (setq direct-superclasses
(slot-value class
'direct-superclasses
)))
659 (let* ((name (class-name class
))
660 (from-defclass-p (slot-value class
'from-defclass-p
))
661 (defstruct-p (or from-defclass-p
(not (structure-type-p name
)))))
663 (setf (slot-value class
'direct-slots
)
667 (let* ((slot-name (getf pl
:name
))
670 "~S structure class ~A"
672 (accessor (intern acc-name
)))
673 (setq pl
(list* :defstruct-accessor-symbol
675 (make-direct-slotd class pl
))
677 (setq direct-slots
(slot-value class
'direct-slots
)))
679 (let ((include (car (slot-value class
'direct-superclasses
))))
680 (multiple-value-bind (defstruct-form constructor reader-names writer-names
)
681 (make-structure-class-defstruct-form name direct-slots include
)
682 (unless (structure-type-p name
) (eval defstruct-form
))
683 (mapc (lambda (dslotd reader-name writer-name
)
684 (let* ((reader (gdefinition reader-name
))
685 (writer (when (gboundp writer-name
)
686 (gdefinition writer-name
))))
687 (setf (slot-value dslotd
'internal-reader-function
)
689 (setf (slot-value dslotd
'internal-writer-function
)
691 direct-slots reader-names writer-names
)
692 (setf (slot-value class
'defstruct-form
) defstruct-form
)
693 (setf (slot-value class
'defstruct-constructor
) constructor
))))
694 (add-direct-subclasses class direct-superclasses
)
695 (setf (slot-value class
'class-precedence-list
)
696 (compute-class-precedence-list class
))
697 (setf (slot-value class
'slots
) (compute-slots class
))
698 (let ((lclass (find-classoid (class-name class
))))
699 (setf (classoid-pcl-class lclass
) class
)
700 (setf (slot-value class
'wrapper
) (classoid-layout lclass
)))
701 (setf (slot-value class
'finalized-p
) t
)
702 (update-pv-table-cache-info class
)
703 (setq predicate-name
(if predicate-name-p
704 (setf (slot-value class
'predicate-name
)
705 (car predicate-name
))
706 (or (slot-value class
'predicate-name
)
707 (setf (slot-value class
'predicate-name
)
708 (make-class-predicate-name
709 (class-name class
))))))
710 (make-class-predicate class predicate-name
)
711 (add-slot-accessors class direct-slots
)))
713 (defmethod direct-slot-definition-class ((class structure-class
) initargs
)
714 (declare (ignore initargs
))
715 (find-class 'structure-direct-slot-definition
))
717 (defmethod finalize-inheritance ((class structure-class
))
718 nil
) ; always finalized
720 (defun add-slot-accessors (class dslotds
)
721 (fix-slot-accessors class dslotds
'add
))
723 (defun remove-slot-accessors (class dslotds
)
724 (fix-slot-accessors class dslotds
'remove
))
726 (defun fix-slot-accessors (class dslotds add
/remove
)
727 (flet ((fix (gfspec name r
/w
)
728 (let ((gf (ensure-generic-function gfspec
)))
730 (r (if (eq add
/remove
'add
)
731 (add-reader-method class gf name
)
732 (remove-reader-method class gf
)))
733 (w (if (eq add
/remove
'add
)
734 (add-writer-method class gf name
)
735 (remove-writer-method class gf
)))))))
736 (dolist (dslotd dslotds
)
737 (let ((slot-name (slot-definition-name dslotd
)))
738 (dolist (r (slot-definition-readers dslotd
)) (fix r slot-name
'r
))
739 (dolist (w (slot-definition-writers dslotd
)) (fix w slot-name
'w
))))))
741 (defun add-direct-subclasses (class supers
)
742 (dolist (super supers
)
743 (unless (memq class
(class-direct-subclasses class
))
744 (add-direct-subclass super class
))))
746 (defun remove-direct-subclasses (class supers
)
747 (let ((old (class-direct-superclasses class
)))
748 (dolist (o (set-difference old supers
))
749 (remove-direct-subclass o class
))))
751 (defmethod finalize-inheritance ((class std-class
))
752 (update-class class t
))
754 (defmethod finalize-inheritance ((class forward-referenced-class
))
755 ;; FIXME: should we not be thinking a bit about what kinds of error
756 ;; we're throwing? Maybe we need a clos-error type to mix in? Or
757 ;; possibly a forward-referenced-class-error, though that's
758 ;; difficult given e.g. class precedence list calculations...
760 "~@<FINALIZE-INHERITANCE was called on a forward referenced class:~
765 (defun class-has-a-forward-referenced-superclass-p (class)
766 (or (forward-referenced-class-p class
)
767 (some #'class-has-a-forward-referenced-superclass-p
768 (class-direct-superclasses class
))))
770 ;;; This is called by :after shared-initialize whenever a class is initialized
771 ;;; or reinitialized. The class may or may not be finalized.
772 (defun update-class (class finalizep
)
773 ;; Comment from Gerd Moellmann:
775 ;; Note that we can't simply delay the finalization when CLASS has
776 ;; no forward referenced superclasses because that causes bootstrap
778 (when (and (not finalizep
)
779 (not (class-finalized-p class
))
780 (not (class-has-a-forward-referenced-superclass-p class
)))
781 (finalize-inheritance class
)
782 (return-from update-class
))
783 (when (or finalizep
(class-finalized-p class
)
784 (not (class-has-a-forward-referenced-superclass-p class
)))
785 (setf (find-class (class-name class
)) class
)
786 (update-cpl class
(compute-class-precedence-list class
))
787 ;; This invocation of UPDATE-SLOTS, in practice, finalizes the
788 ;; class. The hoops above are to ensure that FINALIZE-INHERITANCE
789 ;; is called at finalization, so that MOP programmers can hook
790 ;; into the system as described in "Class Finalization Protocol"
791 ;; (section 5.5.2 of AMOP).
792 (update-slots class
(compute-slots class
))
793 (update-gfs-of-class class
)
794 (update-inits class
(compute-default-initargs class
))
795 (update-ctors 'finalize-inheritance
:class class
))
797 (dolist (sub (class-direct-subclasses class
)) (update-class sub nil
))))
799 (defun update-cpl (class cpl
)
800 (if (class-finalized-p class
)
801 (unless (equal (class-precedence-list class
) cpl
)
802 ;; comment from the old CMU CL sources:
803 ;; Need to have the cpl setup before update-lisp-class-layout
804 ;; is called on CMU CL.
805 (setf (slot-value class
'class-precedence-list
) cpl
)
806 (force-cache-flushes class
))
807 (setf (slot-value class
'class-precedence-list
) cpl
))
808 (update-class-can-precede-p cpl
))
810 (defun update-class-can-precede-p (cpl)
812 (let ((first (car cpl
)))
813 (dolist (c (cdr cpl
))
814 (pushnew c
(slot-value first
'can-precede-list
))))
815 (update-class-can-precede-p (cdr cpl
))))
817 (defun class-can-precede-p (class1 class2
)
818 (member class2
(class-can-precede-list class1
)))
820 (defun update-slots (class eslotds
)
821 (let ((instance-slots ())
823 (dolist (eslotd eslotds
)
824 (let ((alloc (slot-definition-allocation eslotd
)))
826 (:instance
(push eslotd instance-slots
))
827 (:class
(push eslotd class-slots
)))))
829 ;; If there is a change in the shape of the instances then the
830 ;; old class is now obsolete.
831 (let* ((nlayout (mapcar #'slot-definition-name
832 (sort instance-slots
#'<
833 :key
#'slot-definition-location
)))
834 (nslots (length nlayout
))
835 (nwrapper-class-slots (compute-class-slots class-slots
))
836 (owrapper (when (class-finalized-p class
)
837 (class-wrapper class
)))
838 (olayout (when owrapper
839 (wrapper-instance-slots-layout owrapper
)))
840 (owrapper-class-slots (and owrapper
(wrapper-class-slots owrapper
)))
842 (cond ((null owrapper
)
843 (make-wrapper nslots class
))
844 ((and (equal nlayout olayout
)
846 (loop for o in owrapper-class-slots
847 for n in nwrapper-class-slots
848 do
(unless (eq (car o
) (car n
)) (return t
)))))
851 ;; This will initialize the new wrapper to have the
852 ;; same state as the old wrapper. We will then have
853 ;; to change that. This may seem like wasted work
854 ;; (and it is), but the spec requires that we call
855 ;; MAKE-INSTANCES-OBSOLETE.
856 (make-instances-obsolete class
)
857 (class-wrapper class
)))))
859 (with-slots (wrapper slots
) class
860 (update-lisp-class-layout class nwrapper
)
862 (wrapper-instance-slots-layout nwrapper
) nlayout
863 (wrapper-class-slots nwrapper
) nwrapper-class-slots
864 (wrapper-no-of-instance-slots nwrapper
) nslots
866 (setf (slot-value class
'finalized-p
) t
)
867 (unless (eq owrapper nwrapper
)
868 (update-pv-table-cache-info class
)))))
870 (defun compute-class-slots (eslotds)
872 (dolist (eslotd eslotds
)
873 (push (assoc (slot-definition-name eslotd
)
874 (class-slot-cells (slot-definition-class eslotd
)))
878 (defun update-gfs-of-class (class)
879 (when (and (class-finalized-p class
)
880 (let ((cpl (class-precedence-list class
)))
881 (or (member *the-class-slot-class
* cpl
)
882 (member *the-class-standard-effective-slot-definition
*
884 (let ((gf-table (make-hash-table :test
'eq
)))
885 (labels ((collect-gfs (class)
886 (dolist (gf (specializer-direct-generic-functions class
))
887 (setf (gethash gf gf-table
) t
))
888 (mapc #'collect-gfs
(class-direct-superclasses class
))))
890 (maphash (lambda (gf ignore
)
891 (declare (ignore ignore
))
892 (update-gf-dfun class gf
))
895 (defun update-inits (class inits
)
896 (setf (plist-value class
'default-initargs
) inits
))
898 (defmethod compute-default-initargs ((class slot-class
))
899 (let ((cpl (class-precedence-list class
))
900 (direct (class-direct-default-initargs class
)))
901 (labels ((walk (tail)
904 (let ((c (pop tail
)))
905 (append (if (eq c class
)
907 (class-direct-default-initargs c
))
909 (let ((initargs (walk cpl
)))
910 (delete-duplicates initargs
:test
#'eq
:key
#'car
:from-end t
)))))
912 ;;;; protocols for constructing direct and effective slot definitions
914 (defmethod direct-slot-definition-class ((class std-class
) initargs
)
915 (declare (ignore initargs
))
916 (find-class 'standard-direct-slot-definition
))
918 (defun make-direct-slotd (class initargs
)
919 (let ((initargs (list* :class class initargs
)))
920 (apply #'make-instance
921 (direct-slot-definition-class class initargs
)
924 (defmethod compute-slots ((class std-class
))
925 ;; As specified, we must call COMPUTE-EFFECTIVE-SLOT-DEFINITION once
926 ;; for each different slot name we find in our superclasses. Each
927 ;; call receives the class and a list of the dslotds with that name.
928 ;; The list is in most-specific-first order.
929 (let ((name-dslotds-alist ()))
930 (dolist (c (class-precedence-list class
))
931 (dolist (slot (class-direct-slots c
))
932 (let* ((name (slot-definition-name slot
))
933 (entry (assq name name-dslotds-alist
)))
935 (push slot
(cdr entry
))
936 (push (list name slot
) name-dslotds-alist
)))))
937 (mapcar (lambda (direct)
938 (compute-effective-slot-definition class
940 (nreverse (cdr direct
))))
941 name-dslotds-alist
)))
943 (defmethod compute-slots ((class standard-class
))
946 (defmethod compute-slots :around
((class standard-class
))
947 (let ((eslotds (call-next-method))
949 (dolist (eslotd eslotds eslotds
)
950 (setf (slot-definition-location eslotd
)
951 (ecase (slot-definition-allocation eslotd
)
955 (let* ((name (slot-definition-name eslotd
))
956 (from-class (slot-definition-allocation-class eslotd
))
957 (cell (assq name
(class-slot-cells from-class
))))
960 (initialize-internal-slot-functions eslotd
))))
962 (defmethod compute-slots ((class funcallable-standard-class
))
965 (defmethod compute-slots :around
((class funcallable-standard-class
))
966 (labels ((instance-slot-names (slotds)
968 (dolist (slotd slotds
(nreverse collect
))
969 (when (eq (slot-definition-allocation slotd
) :instance
)
970 (push (slot-definition-name slotd
) collect
)))))
971 ;; This sorts slots so that slots of classes later in the CPL
972 ;; come before slots of other classes. This is crucial for
973 ;; funcallable instances because it ensures that the slots of
974 ;; FUNCALLABLE-STANDARD-OBJECT, which includes the slots of
975 ;; KERNEL:FUNCALLABLE-INSTANCE, come first, which in turn
976 ;; makes it possible to treat FUNCALLABLE-STANDARD-OBJECT as
977 ;; a funcallable instance.
978 (compute-layout (eslotds)
980 (names (instance-slot-names eslotds
)))
982 (reverse (class-precedence-list class
))
983 (nreverse (nconc names first
)))
984 (dolist (ss (class-slots class
))
985 (let ((name (slot-definition-name ss
)))
986 (when (member name names
)
988 (setq names
(delete name names
)))))))))
989 (let ((all-slotds (call-next-method))
992 (dolist (slotd all-slotds
)
993 (ecase (slot-definition-allocation slotd
)
994 (:instance
(push slotd instance-slots
))
995 (:class
(push slotd class-slots
))))
996 (let ((layout (compute-layout instance-slots
)))
997 (dolist (slotd instance-slots
)
998 (setf (slot-definition-location slotd
)
999 (position (slot-definition-name slotd
) layout
))
1000 (initialize-internal-slot-functions slotd
)))
1001 (dolist (slotd class-slots
)
1002 (let ((name (slot-definition-name slotd
))
1003 (from-class (slot-definition-allocation-class slotd
)))
1004 (setf (slot-definition-location slotd
)
1005 (assoc name
(class-slot-cells from-class
)))
1006 (aver (consp (slot-definition-location slotd
)))
1007 (initialize-internal-slot-functions slotd
)))
1010 (defmethod compute-slots ((class structure-class
))
1011 (mapcan (lambda (superclass)
1012 (mapcar (lambda (dslotd)
1013 (compute-effective-slot-definition
1015 (slot-definition-name dslotd
)
1017 (class-direct-slots superclass
)))
1018 (reverse (slot-value class
'class-precedence-list
))))
1020 (defmethod compute-slots :around
((class structure-class
))
1021 (let ((eslotds (call-next-method)))
1022 (mapc #'initialize-internal-slot-functions eslotds
)
1025 (defmethod compute-effective-slot-definition ((class slot-class
) name dslotds
)
1026 (declare (ignore name
))
1027 (let* ((initargs (compute-effective-slot-definition-initargs class dslotds
))
1028 (class (effective-slot-definition-class class initargs
)))
1029 (apply #'make-instance class initargs
)))
1031 (defmethod effective-slot-definition-class ((class std-class
) initargs
)
1032 (declare (ignore initargs
))
1033 (find-class 'standard-effective-slot-definition
))
1035 (defmethod effective-slot-definition-class ((class structure-class
) initargs
)
1036 (declare (ignore initargs
))
1037 (find-class 'structure-effective-slot-definition
))
1039 (defmethod compute-effective-slot-definition-initargs
1040 ((class slot-class
) direct-slotds
)
1046 (allocation-class nil
)
1052 (dolist (slotd direct-slotds
)
1055 (setq name
(slot-definition-name slotd
)
1058 (when (slot-definition-initfunction slotd
)
1059 (setq initform
(slot-definition-initform slotd
)
1060 initfunction
(slot-definition-initfunction slotd
)
1063 (setq allocation
(slot-definition-allocation slotd
)
1064 allocation-class
(slot-definition-class slotd
)
1066 (setq initargs
(append (slot-definition-initargs slotd
) initargs
))
1067 (let ((slotd-type (slot-definition-type slotd
)))
1068 (setq type
(cond ((eq type t
) slotd-type
)
1069 ((*subtypep type slotd-type
) type
)
1070 (t `(and ,type
,slotd-type
)))))))
1073 :initfunction initfunction
1075 :allocation allocation
1076 :allocation-class allocation-class
1080 (defmethod compute-effective-slot-definition-initargs :around
1081 ((class structure-class
) direct-slotds
)
1082 (let ((slotd (car direct-slotds
)))
1083 (list* :defstruct-accessor-symbol
1084 (slot-definition-defstruct-accessor-symbol slotd
)
1085 :internal-reader-function
1086 (slot-definition-internal-reader-function slotd
)
1087 :internal-writer-function
1088 (slot-definition-internal-writer-function slotd
)
1089 (call-next-method))))
1091 ;;; NOTE: For bootstrapping considerations, these can't use MAKE-INSTANCE
1092 ;;; to make the method object. They have to use make-a-method which
1093 ;;; is a specially bootstrapped mechanism for making standard methods.
1094 (defmethod reader-method-class ((class slot-class
) direct-slot
&rest initargs
)
1095 (declare (ignore direct-slot initargs
))
1096 (find-class 'standard-reader-method
))
1098 (defmethod add-reader-method ((class slot-class
) generic-function slot-name
)
1099 (add-method generic-function
1100 (make-a-method 'standard-reader-method
1102 (list (or (class-name class
) 'object
))
1104 (make-reader-method-function class slot-name
)
1105 "automatically generated reader method"
1108 (defmethod writer-method-class ((class slot-class
) direct-slot
&rest initargs
)
1109 (declare (ignore direct-slot initargs
))
1110 (find-class 'standard-writer-method
))
1112 (defmethod add-writer-method ((class slot-class
) generic-function slot-name
)
1113 (add-method generic-function
1114 (make-a-method 'standard-writer-method
1116 (list 'new-value
(or (class-name class
) 'object
))
1117 (list *the-class-t
* class
)
1118 (make-writer-method-function class slot-name
)
1119 "automatically generated writer method"
1122 (defmethod add-boundp-method ((class slot-class
) generic-function slot-name
)
1123 (add-method generic-function
1124 (make-a-method 'standard-boundp-method
1126 (list (or (class-name class
) 'object
))
1128 (make-boundp-method-function class slot-name
)
1129 "automatically generated boundp method"
1132 (defmethod remove-reader-method ((class slot-class
) generic-function
)
1133 (let ((method (get-method generic-function
() (list class
) nil
)))
1134 (when method
(remove-method generic-function method
))))
1136 (defmethod remove-writer-method ((class slot-class
) generic-function
)
1138 (get-method generic-function
() (list *the-class-t
* class
) nil
)))
1139 (when method
(remove-method generic-function method
))))
1141 (defmethod remove-boundp-method ((class slot-class
) generic-function
)
1142 (let ((method (get-method generic-function
() (list class
) nil
)))
1143 (when method
(remove-method generic-function method
))))
1145 ;;; MAKE-READER-METHOD-FUNCTION and MAKE-WRITE-METHOD function are NOT
1146 ;;; part of the standard protocol. They are however useful, PCL makes
1147 ;;; use of them internally and documents them for PCL users.
1149 ;;; *** This needs work to make type testing by the writer functions which
1150 ;;; *** do type testing faster. The idea would be to have one constructor
1151 ;;; *** for each possible type test.
1153 ;;; *** There is a subtle bug here which is going to have to be fixed.
1154 ;;; *** Namely, the simplistic use of the template has to be fixed. We
1155 ;;; *** have to give the OPTIMIZE-SLOT-VALUE method the user might have
1156 ;;; *** defined for this metaclass a chance to run.
1158 (defmethod make-reader-method-function ((class slot-class
) slot-name
)
1159 (make-std-reader-method-function (class-name class
) slot-name
))
1161 (defmethod make-writer-method-function ((class slot-class
) slot-name
)
1162 (make-std-writer-method-function (class-name class
) slot-name
))
1164 (defmethod make-boundp-method-function ((class slot-class
) slot-name
)
1165 (make-std-boundp-method-function (class-name class
) slot-name
))
1167 (defmethod compatible-meta-class-change-p (class proto-new-class
)
1168 (eq (class-of class
) (class-of proto-new-class
)))
1170 (defmethod validate-superclass ((class class
) (new-super class
))
1171 (or (eq new-super
*the-class-t
*)
1172 (eq (class-of class
) (class-of new-super
))))
1174 (defmethod validate-superclass ((class standard-class
) (new-super std-class
))
1175 (let ((new-super-meta-class (class-of new-super
)))
1176 (or (eq new-super-meta-class
*the-class-std-class
*)
1177 (eq (class-of class
) new-super-meta-class
))))
1179 ;;; What this does depends on which of the four possible values of
1180 ;;; LAYOUT-INVALID the PCL wrapper has; the simplest case is when it
1181 ;;; is (:FLUSH <wrapper>) or (:OBSOLETE <wrapper>), when there is
1182 ;;; nothing to do, as the new wrapper has already been created. If
1183 ;;; LAYOUT-INVALID returns NIL, then we invalidate it (setting it to
1184 ;;; (:FLUSH <wrapper>); UPDATE-SLOTS later gets to choose whether or
1185 ;;; not to "upgrade" this to (:OBSOLETE <wrapper>).
1187 ;;; This leaves the case where LAYOUT-INVALID returns T, which happens
1188 ;;; when REGISTER-LAYOUT has invalidated a superclass of CLASS (which
1189 ;;; invalidated all the subclasses in SB-KERNEL land). Again, here we
1190 ;;; must flush the caches and allow UPDATE-SLOTS to decide whether to
1191 ;;; obsolete the wrapper.
1193 ;;; FIXME: either here or in INVALID-WRAPPER-P looks like a good place
1194 ;;; for (AVER (NOT (EQ (LAYOUT-INVALID OWRAPPER)
1195 ;;; :UNINITIALIZED)))
1197 ;;; Thanks to Gerd Moellmann for the explanation. -- CSR, 2002-10-29
1198 (defun force-cache-flushes (class)
1199 (let* ((owrapper (class-wrapper class
)))
1200 ;; We only need to do something if the wrapper is still valid. If
1201 ;; the wrapper isn't valid, state will be FLUSH or OBSOLETE, and
1202 ;; both of those will already be doing what we want. In
1203 ;; particular, we must be sure we never change an OBSOLETE into a
1204 ;; FLUSH since OBSOLETE means do what FLUSH does and then some.
1205 (when (or (not (invalid-wrapper-p owrapper
))
1206 ;; KLUDGE: despite the observations above, this remains
1207 ;; a violation of locality or what might be considered
1208 ;; good style. There has to be a better way! -- CSR,
1210 (eq (layout-invalid owrapper
) t
))
1211 (let ((nwrapper (make-wrapper (wrapper-no-of-instance-slots owrapper
)
1213 (setf (wrapper-instance-slots-layout nwrapper
)
1214 (wrapper-instance-slots-layout owrapper
))
1215 (setf (wrapper-class-slots nwrapper
)
1216 (wrapper-class-slots owrapper
))
1218 (update-lisp-class-layout class nwrapper
)
1219 (setf (slot-value class
'wrapper
) nwrapper
)
1220 (invalidate-wrapper owrapper
:flush nwrapper
))))))
1222 (defun flush-cache-trap (owrapper nwrapper instance
)
1223 (declare (ignore owrapper
))
1224 (set-wrapper instance nwrapper
))
1226 ;;; MAKE-INSTANCES-OBSOLETE can be called by user code. It will cause
1227 ;;; the next access to the instance (as defined in 88-002R) to trap
1228 ;;; through the UPDATE-INSTANCE-FOR-REDEFINED-CLASS mechanism.
1229 (defmethod make-instances-obsolete ((class std-class
))
1230 (let* ((owrapper (class-wrapper class
))
1231 (nwrapper (make-wrapper (wrapper-no-of-instance-slots owrapper
)
1233 (setf (wrapper-instance-slots-layout nwrapper
)
1234 (wrapper-instance-slots-layout owrapper
))
1235 (setf (wrapper-class-slots nwrapper
)
1236 (wrapper-class-slots owrapper
))
1238 (update-lisp-class-layout class nwrapper
)
1239 (setf (slot-value class
'wrapper
) nwrapper
)
1240 (invalidate-wrapper owrapper
:obsolete nwrapper
)
1243 (defmethod make-instances-obsolete ((class symbol
))
1244 (make-instances-obsolete (find-class class
)))
1246 ;;; OBSOLETE-INSTANCE-TRAP is the internal trap that is called when we
1247 ;;; see an obsolete instance. The times when it is called are:
1248 ;;; - when the instance is involved in method lookup
1249 ;;; - when attempting to access a slot of an instance
1251 ;;; It is not called by class-of, wrapper-of, or any of the low-level
1252 ;;; instance access macros.
1254 ;;; Of course these times when it is called are an internal
1255 ;;; implementation detail of PCL and are not part of the documented
1256 ;;; description of when the obsolete instance update happens. The
1257 ;;; documented description is as it appears in 88-002R.
1259 ;;; This has to return the new wrapper, so it counts on all the
1260 ;;; methods on obsolete-instance-trap-internal to return the new
1261 ;;; wrapper. It also does a little internal error checking to make
1262 ;;; sure that the traps are only happening when they should, and that
1263 ;;; the trap methods are computing appropriate new wrappers.
1265 ;;; OBSOLETE-INSTANCE-TRAP might be called on structure instances
1266 ;;; after a structure is redefined. In most cases,
1267 ;;; OBSOLETE-INSTANCE-TRAP will not be able to fix the old instance,
1268 ;;; so it must signal an error. The hard part of this is that the
1269 ;;; error system and debugger might cause OBSOLETE-INSTANCE-TRAP to be
1270 ;;; called again, so in that case, we have to return some reasonable
1271 ;;; wrapper, instead.
1273 (defvar *in-obsolete-instance-trap
* nil
)
1274 (defvar *the-wrapper-of-structure-object
*
1275 (class-wrapper (find-class 'structure-object
)))
1277 (define-condition obsolete-structure
(error)
1278 ((datum :reader obsolete-structure-datum
:initarg
:datum
))
1280 (lambda (condition stream
)
1281 ;; Don't try to print the structure, since it probably won't work.
1283 "~@<obsolete structure error for a structure of type ~2I~_~S~:>"
1284 (type-of (obsolete-structure-datum condition
))))))
1286 (defun obsolete-instance-trap (owrapper nwrapper instance
)
1287 (if (not (pcl-instance-p instance
))
1288 (if *in-obsolete-instance-trap
*
1289 *the-wrapper-of-structure-object
*
1290 (let ((*in-obsolete-instance-trap
* t
))
1291 (error 'obsolete-structure
:datum instance
)))
1292 (let* ((class (wrapper-class* nwrapper
))
1293 (copy (allocate-instance class
)) ;??? allocate-instance ???
1294 (olayout (wrapper-instance-slots-layout owrapper
))
1295 (nlayout (wrapper-instance-slots-layout nwrapper
))
1296 (oslots (get-slots instance
))
1297 (nslots (get-slots copy
))
1298 (oclass-slots (wrapper-class-slots owrapper
))
1302 ;; local --> local transfer
1303 ;; local --> shared discard
1304 ;; local --> -- discard
1305 ;; shared --> local transfer
1306 ;; shared --> shared discard
1307 ;; shared --> -- discard
1311 ;; Go through all the old local slots.
1313 (dolist (name olayout
)
1314 (let ((npos (posq name nlayout
)))
1316 (setf (clos-slots-ref nslots npos
)
1317 (clos-slots-ref oslots opos
))
1319 (push name discarded
)
1320 (unless (eq (clos-slots-ref oslots opos
) +slot-unbound
+)
1321 (setf (getf plist name
) (clos-slots-ref oslots opos
))))))
1324 ;; Go through all the old shared slots.
1325 (dolist (oclass-slot-and-val oclass-slots
)
1326 (let ((name (car oclass-slot-and-val
))
1327 (val (cdr oclass-slot-and-val
)))
1328 (let ((npos (posq name nlayout
)))
1330 (setf (clos-slots-ref nslots npos
) (cdr oclass-slot-and-val
))
1331 (progn (push name discarded
)
1332 (unless (eq val
+slot-unbound
+)
1333 (setf (getf plist name
) val
)))))))
1335 ;; Go through all the new local slots to compute the added slots.
1336 (dolist (nlocal nlayout
)
1337 (unless (or (memq nlocal olayout
)
1338 (assq nlocal oclass-slots
))
1339 (push nlocal added
)))
1341 (swap-wrappers-and-slots instance copy
)
1343 (update-instance-for-redefined-class instance
1349 (defun change-class-internal (instance new-class initargs
)
1350 (let* ((old-class (class-of instance
))
1351 (copy (allocate-instance new-class
))
1352 (new-wrapper (get-wrapper copy
))
1353 (old-wrapper (class-wrapper old-class
))
1354 (old-layout (wrapper-instance-slots-layout old-wrapper
))
1355 (new-layout (wrapper-instance-slots-layout new-wrapper
))
1356 (old-slots (get-slots instance
))
1357 (new-slots (get-slots copy
))
1358 (old-class-slots (wrapper-class-slots old-wrapper
)))
1360 ;; "The values of local slots specified by both the class CTO and
1361 ;; CFROM are retained. If such a local slot was unbound, it
1362 ;; remains unbound."
1363 (let ((new-position 0))
1364 (dolist (new-slot new-layout
)
1365 (let ((old-position (posq new-slot old-layout
)))
1367 (setf (clos-slots-ref new-slots new-position
)
1368 (clos-slots-ref old-slots old-position
))))
1369 (incf new-position
)))
1371 ;; "The values of slots specified as shared in the class CFROM and
1372 ;; as local in the class CTO are retained."
1373 (dolist (slot-and-val old-class-slots
)
1374 (let ((position (posq (car slot-and-val
) new-layout
)))
1376 (setf (clos-slots-ref new-slots position
) (cdr slot-and-val
)))))
1378 ;; Make the copy point to the old instance's storage, and make the
1379 ;; old instance point to the new storage.
1380 (swap-wrappers-and-slots instance copy
)
1382 (apply #'update-instance-for-different-class copy instance initargs
)
1385 (defmethod change-class ((instance standard-object
)
1386 (new-class standard-class
)
1388 (change-class-internal instance new-class initargs
))
1390 (defmethod change-class ((instance funcallable-standard-object
)
1391 (new-class funcallable-standard-class
)
1393 (change-class-internal instance new-class initargs
))
1395 (defmethod change-class ((instance standard-object
)
1396 (new-class funcallable-standard-class
)
1398 (declare (ignore initargs
))
1399 (error "You can't change the class of ~S to ~S~@
1400 because it isn't already an instance with metaclass ~S."
1401 instance new-class
'standard-class
))
1403 (defmethod change-class ((instance funcallable-standard-object
)
1404 (new-class standard-class
)
1406 (declare (ignore initargs
))
1407 (error "You can't change the class of ~S to ~S~@
1408 because it isn't already an instance with metaclass ~S."
1409 instance new-class
'funcallable-standard-class
))
1411 (defmethod change-class ((instance t
) (new-class-name symbol
) &rest initargs
)
1412 (apply #'change-class instance
(find-class new-class-name
) initargs
))
1414 ;;;; The metaclass BUILT-IN-CLASS
1416 ;;;; This metaclass is something of a weird creature. By this point, all
1417 ;;;; instances of it which will exist have been created, and no instance
1418 ;;;; is ever created by calling MAKE-INSTANCE.
1420 ;;;; But, there are other parts of the protocol we must follow and those
1421 ;;;; definitions appear here.
1423 (defmethod shared-initialize :before
1424 ((class built-in-class
) slot-names
&rest initargs
)
1425 (declare (ignore slot-names initargs
))
1426 (error "attempt to initialize or reinitialize a built in class"))
1428 (defmethod class-direct-slots ((class built-in-class
)) ())
1429 (defmethod class-slots ((class built-in-class
)) ())
1430 (defmethod class-direct-default-initargs ((class built-in-class
)) ())
1431 (defmethod class-default-initargs ((class built-in-class
)) ())
1433 (defmethod validate-superclass ((c class
) (s built-in-class
))
1434 (or (eq s
*the-class-t
*)
1435 (eq s
*the-class-stream
*)))
1437 ;;; Some necessary methods for FORWARD-REFERENCED-CLASS
1438 (defmethod class-direct-slots ((class forward-referenced-class
)) ())
1439 (defmethod class-direct-default-initargs ((class forward-referenced-class
)) ())
1440 (macrolet ((def (method)
1441 `(defmethod ,method
((class forward-referenced-class
))
1442 (error "~@<~I~S was called on a forward referenced class:~2I~_~S~:>"
1444 (def class-default-initargs
)
1445 (def class-precedence-list
)
1448 (defmethod validate-superclass ((c slot-class
)
1449 (f forward-referenced-class
))
1452 (defmethod add-dependent ((metaobject dependent-update-mixin
) dependent
)
1453 (pushnew dependent
(plist-value metaobject
'dependents
)))
1455 (defmethod remove-dependent ((metaobject dependent-update-mixin
) dependent
)
1456 (setf (plist-value metaobject
'dependents
)
1457 (delete dependent
(plist-value metaobject
'dependents
))))
1459 (defmethod map-dependents ((metaobject dependent-update-mixin
) function
)
1460 (dolist (dependent (plist-value metaobject
'dependents
))
1461 (funcall function dependent
)))