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
27 (defun make-progn (&rest forms)
28 (let ((progn-form nil))
29 (labels ((collect-forms (forms)
31 (collect-forms (cdr forms))
32 (if (and (listp (car forms))
33 (eq (caar forms) 'progn))
34 (collect-forms (cdar forms))
35 (push (car forms) progn-form)))))
37 (cons 'progn progn-form))))
39 ;;; Like the DEFMETHOD macro, the expansion of the DEFCLASS macro is
40 ;;; fixed. DEFCLASS always expands into a call to LOAD-DEFCLASS. Until
41 ;;; the meta-braid is set up, LOAD-DEFCLASS has a special definition
42 ;;; which simply collects all class definitions up, when the metabraid
43 ;;; is initialized it is done from those class definitions.
45 ;;; After the metabraid has been setup, and the protocol for defining
46 ;;; classes has been defined, the real definition of LOAD-DEFCLASS is
47 ;;; installed by the file std-class.lisp
48 (defmacro defclass (name %direct-superclasses %direct-slots &rest %options)
49 (setq supers (copy-tree %direct-superclasses)
50 slots (copy-tree %direct-slots)
51 options (copy-tree %options))
52 (let ((metaclass 'standard-class))
53 (dolist (option options)
54 (if (not (listp option))
55 (error "~S is not a legal defclass option." option)
56 (when (eq (car option) ':metaclass)
57 (unless (legal-class-name-p (cadr option))
58 (error "The value of the :metaclass option (~S) is not a~%~
63 (cl:standard-class 'standard-class)
64 (cl:structure-class 'structure-class)
66 (setf options (remove option options))
69 (let ((*initfunctions* ())
70 (*readers* ()) ;Truly a crock, but we got
71 (*writers* ())) ;to have it to live nicely.
72 (declare (special *initfunctions* *readers* *writers*))
73 (let ((canonical-slots
74 (mapcar #'(lambda (spec)
75 (canonicalize-slot-specification name spec))
78 (mapcar #'(lambda (option)
79 (canonicalize-defclass-option name option))
81 ;; FIXME: What does this flag mean?
82 (defstruct-p (and (eq *boot-state* 'complete)
83 (let ((mclass (find-class metaclass nil)))
87 *the-class-structure-class*))))))
91 `(declaim (ftype (function (t) t) ,x)))
94 `(declaim (ftype (function (t t) t) ,x)))
96 (let ,(mapcar #'cdr *initfunctions*)
100 (list ,@canonical-slots)
101 (list ,@(apply #'append
103 '(:from-defclass-p t))
104 other-initargs)))))))
107 ;; FIXME: The ANSI way to do this is with EVAL-WHEN
108 ;; forms, not by side-effects at macroexpansion time.
109 ;; But I (WHN 2001-09-02) am not even sure how to
110 ;; reach this code path with ANSI (or art-of-the-MOP)
111 ;; code, so I haven't tried to update it, since for
112 ;; all I know maybe it could just be deleted instead.
113 (eval defclass-form) ; Define the class now, so that..
114 `(progn ; ..the defstruct can be compiled.
115 ,(class-defstruct-form (find-class name))
118 ;; By telling the type system at compile time about
119 ;; the existence of a class named NAME, we can avoid
120 ;; various bogus warnings about "type isn't defined yet".
122 ;; But it's not so important to get rid of
123 ;; "not defined yet" warnings during
124 ;; bootstrapping, and machinery like
125 ;; INFORM-TYPE-SYSTEM-ABOUT-STD-CLASS
126 ;; mightn't be defined yet. So punt then.
127 (eq *boot-state* 'complete)
128 ;; And although we know enough about
129 ;; STANDARD-CLASS, and ANSI imposes enough
130 ;; restrictions on the user overloading its
131 ;; methods, that (1) we can shortcut the
132 ;; method dispatch and do an ordinary
133 ;; function call, and (2) be sure we're getting
134 ;; it right even when we do it at compile
135 ;; time; we don't in general know how to do
136 ;; that for other classes. So punt then too.
137 (eq metaclass 'standard-class))
138 `(eval-when (:compile-toplevel :load-toplevel :execute)
139 (inform-type-system-about-std-class ',name)))
140 ,defclass-form)))))))
142 (defun make-initfunction (initform)
143 (declare (special *initfunctions*))
144 (cond ((or (eq initform t)
145 (equal initform ''t))
146 '(function constantly-t))
147 ((or (eq initform nil)
148 (equal initform ''nil))
149 '(function constantly-nil))
150 ((or (eql initform 0)
151 (equal initform ''0))
152 '(function constantly-0))
154 (let ((entry (assoc initform *initfunctions* :test #'equal)))
156 (setq entry (list initform
158 `(function (lambda () ,initform))))
159 (push entry *initfunctions*))
162 (defun canonicalize-slot-specification (class-name spec)
163 (declare (special *readers* *writers*))
164 (cond ((and (symbolp spec)
165 (not (keywordp spec))
166 (not (memq spec '(t nil))))
169 (error "~S is not a legal slot specification." spec))
171 `'(:name ,(car spec)))
173 (error "In DEFCLASS ~S, the slot specification ~S is obsolete.~%~
175 class-name spec (list (car spec) :initform (cadr spec))))
177 (let* ((name (pop spec))
181 (unsupplied (list nil))
182 (initform (getf spec :initform unsupplied)))
183 (doplist (key val) spec
185 (:accessor (push val readers)
186 (push `(setf ,val) writers))
187 (:reader (push val readers))
188 (:writer (push val writers))
189 (:initarg (push val initargs))))
190 (loop (unless (remf spec :accessor) (return)))
191 (loop (unless (remf spec :reader) (return)))
192 (loop (unless (remf spec :writer) (return)))
193 (loop (unless (remf spec :initarg) (return)))
194 (setq *writers* (append writers *writers*))
195 (setq *readers* (append readers *readers*))
196 (setq spec `(:name ',name
201 (if (eq initform unsupplied)
203 `(list* :initfunction ,(make-initfunction initform) ,@spec))))))
205 (defun canonicalize-defclass-option (class-name option)
206 (declare (ignore class-name))
209 (let ((canonical ()))
210 (let (key val (tail (cdr option)))
211 (loop (when (null tail) (return nil))
214 (push ``(,',key ,,(make-initfunction val) ,',val) canonical))
215 `(':direct-default-initargs (list ,@(nreverse canonical))))))
217 `(',(car option) ',(cadr option)))
219 `(',(car option) ',(cdr option)))))
221 ;;; This is the early definition of load-defclass. It just collects up
222 ;;; all the class definitions in a list. Later, in the file
223 ;;; braid1.lisp, these are actually defined.
225 ;;; Each entry in *EARLY-CLASS-DEFINITIONS* is an EARLY-CLASS-DEFINITION.
226 (defparameter *early-class-definitions* ())
228 (defun early-class-definition (class-name)
229 (or (find class-name *early-class-definitions* :key #'ecd-class-name)
230 (error "~S is not a class in *early-class-definitions*." class-name)))
232 (defun make-early-class-definition
233 (name source metaclass
234 superclass-names canonical-slots other-initargs)
235 (list 'early-class-definition
236 name source metaclass
237 superclass-names canonical-slots other-initargs))
239 (defun ecd-class-name (ecd) (nth 1 ecd))
240 (defun ecd-source (ecd) (nth 2 ecd))
241 (defun ecd-metaclass (ecd) (nth 3 ecd))
242 (defun ecd-superclass-names (ecd) (nth 4 ecd))
243 (defun ecd-canonical-slots (ecd) (nth 5 ecd))
244 (defun ecd-other-initargs (ecd) (nth 6 ecd))
246 (defvar *early-class-slots* nil)
248 (defun canonical-slot-name (canonical-slot)
249 (getf canonical-slot :name))
251 (defun early-class-slots (class-name)
252 (cdr (or (assoc class-name *early-class-slots*)
253 (let ((a (cons class-name
254 (mapcar #'canonical-slot-name
255 (early-collect-inheritance class-name)))))
256 (push a *early-class-slots*)
259 (defun early-class-size (class-name)
260 (length (early-class-slots class-name)))
262 (defun early-collect-inheritance (class-name)
263 ;;(declare (values slots cpl default-initargs direct-subclasses))
264 (let ((cpl (early-collect-cpl class-name)))
265 (values (early-collect-slots cpl)
267 (early-collect-default-initargs cpl)
268 (gathering1 (collecting)
269 (dolist (definition *early-class-definitions*)
270 (when (memq class-name (ecd-superclass-names definition))
271 (gather1 (ecd-class-name definition))))))))
273 (defun early-collect-slots (cpl)
274 (let* ((definitions (mapcar #'early-class-definition cpl))
275 (super-slots (mapcar #'ecd-canonical-slots definitions))
276 (slots (apply #'append (reverse super-slots))))
278 (let ((name1 (canonical-slot-name s1)))
279 (dolist (s2 (cdr (memq s1 slots)))
280 (when (eq name1 (canonical-slot-name s2))
281 (error "More than one early class defines a slot with the~%~
282 name ~S. This can't work because the bootstrap~%~
283 object system doesn't know how to compute effective~%~
288 (defun early-collect-cpl (class-name)
290 (let* ((definition (early-class-definition c))
291 (supers (ecd-superclass-names definition)))
293 (apply #'append (mapcar #'early-collect-cpl supers))))))
294 (remove-duplicates (walk class-name) :from-end nil :test #'eq)))
296 (defun early-collect-default-initargs (cpl)
297 (let ((default-initargs ()))
298 (dolist (class-name cpl)
299 (let* ((definition (early-class-definition class-name))
300 (others (ecd-other-initargs definition)))
301 (loop (when (null others) (return nil))
302 (let ((initarg (pop others)))
303 (unless (eq initarg :direct-default-initargs)
304 (error "~@<The defclass option ~S is not supported by ~
305 the bootstrap object system.~:@>"
307 (setq default-initargs
308 (nconc default-initargs (reverse (pop others)))))))
309 (reverse default-initargs)))
311 (defun !bootstrap-slot-index (class-name slot-name)
312 (or (position slot-name (early-class-slots class-name))
313 (error "~S not found" slot-name)))
315 ;;; !BOOTSTRAP-GET-SLOT and !BOOTSTRAP-SET-SLOT are used to access and
316 ;;; change the values of slots during bootstrapping. During
317 ;;; bootstrapping, there are only two kinds of objects whose slots we
318 ;;; need to access, CLASSes and SLOT-DEFINITIONs. The first argument
319 ;;; to these functions tells whether the object is a CLASS or a
322 ;;; Note that the way this works it stores the slot in the same place
323 ;;; in memory that the full object system will expect to find it
324 ;;; later. This is critical to the bootstrapping process, the whole
325 ;;; changeover to the full object system is predicated on this.
327 ;;; One important point is that the layout of standard classes and
328 ;;; standard slots must be computed the same way in this file as it is
329 ;;; by the full object system later.
330 (defmacro !bootstrap-get-slot (type object slot-name)
331 `(clos-slots-ref (get-slots ,object)
332 (!bootstrap-slot-index ,type ,slot-name)))
333 (defun !bootstrap-set-slot (type object slot-name new-value)
334 (setf (!bootstrap-get-slot type object slot-name) new-value))
336 (defun early-class-name (class)
337 (!bootstrap-get-slot 'class class 'name))
339 (defun early-class-precedence-list (class)
340 (!bootstrap-get-slot 'pcl-class class 'class-precedence-list))
342 (defun early-class-name-of (instance)
343 (early-class-name (class-of instance)))
345 (defun early-class-slotds (class)
346 (!bootstrap-get-slot 'slot-class class 'slots))
348 (defun early-slot-definition-name (slotd)
349 (!bootstrap-get-slot 'standard-effective-slot-definition slotd 'name))
351 (defun early-slot-definition-location (slotd)
352 (!bootstrap-get-slot 'standard-effective-slot-definition slotd 'location))
354 (defun early-accessor-method-slot-name (method)
355 (!bootstrap-get-slot 'standard-accessor-method method 'slot-name))
357 (unless (fboundp 'class-name-of)
358 (setf (symbol-function 'class-name-of)
359 (symbol-function 'early-class-name-of)))
360 (unintern 'early-class-name-of)
362 (defun early-class-direct-subclasses (class)
363 (!bootstrap-get-slot 'class class 'direct-subclasses))
365 (declaim (notinline load-defclass))
366 (defun load-defclass (name metaclass supers canonical-slots canonical-options)
367 (setq supers (copy-tree supers)
368 canonical-slots (copy-tree canonical-slots)
369 canonical-options (copy-tree canonical-options))
370 (when (eq metaclass 'standard-class)
371 (inform-type-system-about-std-class name))
373 (make-early-class-definition name
380 (find name *early-class-definitions* :key #'ecd-class-name)))
381 (setq *early-class-definitions*
382 (cons ecd (remove existing *early-class-definitions*)))