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 defclass.lisp
48 (defmacro defclass (name direct-superclasses direct-slots &rest options)
49 (expand-defclass name direct-superclasses direct-slots options))
51 (defun expand-defclass (name supers slots options)
52 ;; FIXME: We should probably just ensure that the relevant
53 ;; DEFVAR/DEFPARAMETERs occur before this definition, rather
54 ;; than locally declaring them SPECIAL.
55 (declare (special *boot-state* *the-class-structure-class*))
56 (setq supers (copy-tree supers)
57 slots (copy-tree slots)
58 options (copy-tree options))
59 (let ((metaclass 'standard-class))
60 (dolist (option options)
61 (if (not (listp option))
62 (error "~S is not a legal defclass option." option)
63 (when (eq (car option) ':metaclass)
64 (unless (legal-class-name-p (cadr option))
65 (error "The value of the :metaclass option (~S) is not a~%~
70 (cl:standard-class 'standard-class)
71 (cl:structure-class 'structure-class)
73 (setf options (remove option options))
76 (let ((*initfunctions* ())
77 (*readers* ()) ;Truly a crock, but we got
78 (*writers* ())) ;to have it to live nicely.
79 (declare (special *initfunctions* *readers* *writers*))
80 (let ((canonical-slots
81 (mapcar #'(lambda (spec)
82 (canonicalize-slot-specification name spec))
85 (mapcar #'(lambda (option)
86 (canonicalize-defclass-option name option))
88 (defstruct-p (and (eq *boot-state* 'complete)
89 (let ((mclass (find-class metaclass nil)))
93 *the-class-structure-class*))))))
97 `(declaim (ftype (function (t) t) ,x)))
100 `(declaim (ftype (function (t t) t) ,x)))
102 (let ,(mapcar #'cdr *initfunctions*)
103 (load-defclass ',name
106 (list ,@canonical-slots)
107 (list ,@(apply #'append
109 '(:from-defclass-p t))
110 other-initargs)))))))
111 ;; FIXME: The way that we do things like (EVAL DEFCLASS-FORM)
112 ;; here is un-ANSI-Common-Lisp-y and leads to problems
113 ;; (like DEFUN for the type predicate being called more than
114 ;; once when we do DEFCLASS at the interpreter prompt),
115 ;; causing bogus style warnings. It would be better to
116 ;; rewrite this so that the macroexpansion looks like e.g.
118 ;; (EVAL-WHEN (:COMPILE-TOPLEVEL :LOAD-TOPLEVEL :EXECUTE)
120 ;; (EVAL-WHEN (:LOAD-TOPLEVEL :EXECUTE)
124 (eval defclass-form) ; Define the class now, so that..
125 `(progn ; ..the defstruct can be compiled.
126 ,(class-defstruct-form (find-class name))
129 (when (eq *boot-state* 'complete)
130 (inform-type-system-about-std-class name))
133 (defun make-initfunction (initform)
134 (declare (special *initfunctions*))
135 (cond ((or (eq initform t)
136 (equal initform ''t))
137 '(function constantly-t))
138 ((or (eq initform nil)
139 (equal initform ''nil))
140 '(function constantly-nil))
141 ((or (eql initform 0)
142 (equal initform ''0))
143 '(function constantly-0))
145 (let ((entry (assoc initform *initfunctions* :test #'equal)))
147 (setq entry (list initform
149 `(function (lambda () ,initform))))
150 (push entry *initfunctions*))
153 (defun canonicalize-slot-specification (class-name spec)
154 (declare (special *readers* *writers*))
155 (cond ((and (symbolp spec)
156 (not (keywordp spec))
157 (not (memq spec '(t nil))))
160 (error "~S is not a legal slot specification." spec))
162 `'(:name ,(car spec)))
164 (error "In DEFCLASS ~S, the slot specification ~S is obsolete.~%~
166 class-name spec (list (car spec) :initform (cadr spec))))
168 (let* ((name (pop spec))
172 (unsupplied (list nil))
173 (initform (getf spec :initform unsupplied)))
174 (doplist (key val) spec
176 (:accessor (push val readers)
177 (push `(setf ,val) writers))
178 (:reader (push val readers))
179 (:writer (push val writers))
180 (:initarg (push val initargs))))
181 (loop (unless (remf spec :accessor) (return)))
182 (loop (unless (remf spec :reader) (return)))
183 (loop (unless (remf spec :writer) (return)))
184 (loop (unless (remf spec :initarg) (return)))
185 (setq *writers* (append writers *writers*))
186 (setq *readers* (append readers *readers*))
187 (setq spec `(:name ',name
192 (if (eq initform unsupplied)
194 `(list* :initfunction ,(make-initfunction initform) ,@spec))))))
196 (defun canonicalize-defclass-option (class-name option)
197 (declare (ignore class-name))
200 (let ((canonical ()))
201 (let (key val (tail (cdr option)))
202 (loop (when (null tail) (return nil))
205 (push ``(,',key ,,(make-initfunction val) ,',val) canonical))
206 `(':direct-default-initargs (list ,@(nreverse canonical))))))
208 `(',(car option) ',(cadr option)))
210 `(',(car option) ',(cdr option)))))
212 ;;; This is the early definition of load-defclass. It just collects up
213 ;;; all the class definitions in a list. Later, in the file
214 ;;; braid1.lisp, these are actually defined.
216 ;;; Each entry in *EARLY-CLASS-DEFINITIONS* is an EARLY-CLASS-DEFINITION.
217 (defparameter *early-class-definitions* ())
219 (defun early-class-definition (class-name)
220 (or (find class-name *early-class-definitions* :key #'ecd-class-name)
221 (error "~S is not a class in *early-class-definitions*." class-name)))
223 (defun make-early-class-definition
224 (name source metaclass
225 superclass-names canonical-slots other-initargs)
226 (list 'early-class-definition
227 name source metaclass
228 superclass-names canonical-slots other-initargs))
230 (defun ecd-class-name (ecd) (nth 1 ecd))
231 (defun ecd-source (ecd) (nth 2 ecd))
232 (defun ecd-metaclass (ecd) (nth 3 ecd))
233 (defun ecd-superclass-names (ecd) (nth 4 ecd))
234 (defun ecd-canonical-slots (ecd) (nth 5 ecd))
235 (defun ecd-other-initargs (ecd) (nth 6 ecd))
237 (defvar *early-class-slots* nil)
239 (defun canonical-slot-name (canonical-slot)
240 (getf canonical-slot :name))
242 (defun early-class-slots (class-name)
243 (cdr (or (assoc class-name *early-class-slots*)
244 (let ((a (cons class-name
245 (mapcar #'canonical-slot-name
246 (early-collect-inheritance class-name)))))
247 (push a *early-class-slots*)
250 (defun early-class-size (class-name)
251 (length (early-class-slots class-name)))
253 (defun early-collect-inheritance (class-name)
254 ;;(declare (values slots cpl default-initargs direct-subclasses))
255 (let ((cpl (early-collect-cpl class-name)))
256 (values (early-collect-slots cpl)
258 (early-collect-default-initargs cpl)
259 (gathering1 (collecting)
260 (dolist (definition *early-class-definitions*)
261 (when (memq class-name (ecd-superclass-names definition))
262 (gather1 (ecd-class-name definition))))))))
264 (defun early-collect-slots (cpl)
265 (let* ((definitions (mapcar #'early-class-definition cpl))
266 (super-slots (mapcar #'ecd-canonical-slots definitions))
267 (slots (apply #'append (reverse super-slots))))
269 (let ((name1 (canonical-slot-name s1)))
270 (dolist (s2 (cdr (memq s1 slots)))
271 (when (eq name1 (canonical-slot-name s2))
272 (error "More than one early class defines a slot with the~%~
273 name ~S. This can't work because the bootstrap~%~
274 object system doesn't know how to compute effective~%~
279 (defun early-collect-cpl (class-name)
281 (let* ((definition (early-class-definition c))
282 (supers (ecd-superclass-names definition)))
284 (apply #'append (mapcar #'early-collect-cpl supers))))))
285 (remove-duplicates (walk class-name) :from-end nil :test #'eq)))
287 (defun early-collect-default-initargs (cpl)
288 (let ((default-initargs ()))
289 (dolist (class-name cpl)
290 (let* ((definition (early-class-definition class-name))
291 (others (ecd-other-initargs definition)))
292 (loop (when (null others) (return nil))
293 (let ((initarg (pop others)))
294 (unless (eq initarg :direct-default-initargs)
295 (error "~@<The defclass option ~S is not supported by ~
296 the bootstrap object system.~:@>"
298 (setq default-initargs
299 (nconc default-initargs (reverse (pop others)))))))
300 (reverse default-initargs)))
302 (defun !bootstrap-slot-index (class-name slot-name)
303 (or (position slot-name (early-class-slots class-name))
304 (error "~S not found" slot-name)))
306 ;;; !BOOTSTRAP-GET-SLOT and !BOOTSTRAP-SET-SLOT are used to access and
307 ;;; change the values of slots during bootstrapping. During
308 ;;; bootstrapping, there are only two kinds of objects whose slots we
309 ;;; need to access, CLASSes and SLOT-DEFINITIONs. The first argument
310 ;;; to these functions tells whether the object is a CLASS or a
313 ;;; Note that the way this works it stores the slot in the same place
314 ;;; in memory that the full object system will expect to find it
315 ;;; later. This is critical to the bootstrapping process, the whole
316 ;;; changeover to the full object system is predicated on this.
318 ;;; One important point is that the layout of standard classes and
319 ;;; standard slots must be computed the same way in this file as it is
320 ;;; by the full object system later.
321 (defmacro !bootstrap-get-slot (type object slot-name)
322 `(clos-slots-ref (get-slots ,object)
323 (!bootstrap-slot-index ,type ,slot-name)))
324 (defun !bootstrap-set-slot (type object slot-name new-value)
325 (setf (!bootstrap-get-slot type object slot-name) new-value))
327 (defun early-class-name (class)
328 (!bootstrap-get-slot 'class class 'name))
330 (defun early-class-precedence-list (class)
331 (!bootstrap-get-slot 'pcl-class class 'class-precedence-list))
333 (defun early-class-name-of (instance)
334 (early-class-name (class-of instance)))
336 (defun early-class-slotds (class)
337 (!bootstrap-get-slot 'slot-class class 'slots))
339 (defun early-slot-definition-name (slotd)
340 (!bootstrap-get-slot 'standard-effective-slot-definition slotd 'name))
342 (defun early-slot-definition-location (slotd)
343 (!bootstrap-get-slot 'standard-effective-slot-definition slotd 'location))
345 (defun early-accessor-method-slot-name (method)
346 (!bootstrap-get-slot 'standard-accessor-method method 'slot-name))
348 (unless (fboundp 'class-name-of)
349 (setf (symbol-function 'class-name-of)
350 (symbol-function 'early-class-name-of)))
351 (unintern 'early-class-name-of)
353 (defun early-class-direct-subclasses (class)
354 (!bootstrap-get-slot 'class class 'direct-subclasses))
356 (declaim (notinline load-defclass))
357 (defun load-defclass (name metaclass supers canonical-slots canonical-options)
358 (setq supers (copy-tree supers)
359 canonical-slots (copy-tree canonical-slots)
360 canonical-options (copy-tree canonical-options))
361 (when (eq metaclass 'standard-class)
362 (inform-type-system-about-std-class name))
364 (make-early-class-definition name
371 (find name *early-class-definitions* :key #'ecd-class-name)))
372 (setq *early-class-definitions*
373 (cons ecd (remove existing *early-class-definitions*)))