1 ;;; written by David Lichteblau, based on code by Christophe Rhodes,
4 ;;; http://www.lichteblau.com/git/?p=specializable.git;a=blob_plain;f=specializable.lisp;hb=eb30d235951c3c1d128811278760f1db36cd336c
6 (defpackage "SPECIALIZABLE"
8 (:export "SPECIALIZABLE-GENERIC-FUNCTION" "SPECIALIZABLE-METHOD"
11 "SPECIALIZER-ACCEPTS-P" "SPECIALIZER-ACCEPTS-GENERALIZER-P"
14 "GENERALIZER-OF-USING-CLASS"
15 "COMPUTE-APPLICABLE-METHODS-USING-GENERALIZERS"
16 "GENERALIZER-EQUAL-HASH-KEY"
18 "DEFINE-EXTENDED-SPECIALIZER"))
20 (in-package "SPECIALIZABLE")
22 (defclass extended-specializer (sb-mop:specializer)
23 ;; FIXME: this doesn't actually do quite what I wanted.
24 ((direct-methods-table :allocation :class
25 :initform nil :accessor direct-methods-table)))
27 (defmethod sb-mop:add-direct-method ((specializer extended-specializer) method)
28 (let* ((table (direct-methods-table specializer))
29 (cell (assoc specializer table :test #'sb-pcl::same-specializer-p)))
31 (setf cell (cons specializer nil))
32 (push cell (direct-methods-table specializer)))
33 (push method (cdr cell))))
35 (defmethod sb-mop:remove-direct-method ((specializer extended-specializer) method)
36 (let* ((table (direct-methods-table specializer))
37 (cell (assoc specializer table :test #'sb-pcl::same-specializer-p)))
38 (setf (cdr cell) (remove method (cdr cell)))))
40 (defmethod sb-mop:specializer-direct-methods ((specializer extended-specializer))
41 (cdr (assoc specializer (direct-methods-table specializer)
42 :test #'sb-pcl::same-specializer-p)))
43 (defmethod sb-mop:specializer-direct-generic-functions ((specializer extended-specializer))
44 (remove-duplicates (mapcar #'sb-mop:method-generic-function (sb-mop:specializer-direct-methods specializer))))
46 (defclass specializable-generic-function (standard-generic-function)
47 ((emf-table :initform (make-hash-table :test 'equal) :reader emf-table)
48 (cacheingp :initform t :initarg :cacheingp)
49 (single-arg-cacheing-p :initform t :initarg :single-arg-cacheing-p))
50 (:metaclass sb-mop:funcallable-standard-class)
51 (:default-initargs :method-class (find-class 'specializable-method)))
53 ;;; TODO: we don't use this class yet, but we might do later
54 (defclass specializable-method (standard-method) ())
56 (defmacro define-extended-specializer (name (gf-var &rest args) &body body)
58 `(setf (get ',name 'extended-specializer-parser)
59 (lambda (,gf-var ,@args)
62 ;; doesn't work, because we'd have to dump GF into the fasl for the macro
64 ;;; (defun intern-extended-specializer (gf sname)
65 ;;; (destructuring-bind (kind &rest args) sname
66 ;;; (setf (gethash sname (generic-function-extended-specializers gf))
67 ;;; (apply (or (get kind 'extended-specializer-parser)
68 ;;; (error "not declared as an extended specializer name: ~A"
73 (defun make-extended-specializer (sname)
74 (destructuring-bind (kind &rest args) sname
75 (apply (or (get kind 'extended-specializer-parser)
76 (error "not declared as an extended specializer name: ~A"
78 '|This is not a generic function| ;fixme, see comment above
83 (defmethod sb-pcl:parse-specializer-using-class
84 ((gf specializable-generic-function) name)
86 ((typep name 'sb-mop:specializer) name)
87 ((symbolp name) (find-class name))
90 (eql (sb-mop:intern-eql-specializer (cadr name)))
91 (t (make-extended-specializer name))))
92 (t (error "unexpected specializer name"))))
94 (defmethod sb-pcl:make-method-specializers-form
95 ((gf specializable-generic-function) method snames env)
96 (declare (ignore method env))
99 ((typep name 'sb-mop:specializer) name)
100 ((symbolp name) `(find-class ',name))
103 (eql `(sb-mop:intern-eql-specializer ,(cadr name)))
104 (t `(make-extended-specializer ',name))))
105 (t (error "unexpected specializer name")))))
106 `(list ,@(mapcar #'parse snames))))
108 ;;; from Closette, changed to use some SBCL functions:
110 ;;; FIXME: this is not actually sufficient argument checking
111 (defun required-portion (gf args)
112 (let ((number-required
113 (sb-pcl::arg-info-number-required (sb-pcl::gf-arg-info gf))))
114 (when (< (length args) number-required)
115 (error "Too few arguments to generic function ~S." gf))
116 (subseq args 0 number-required)))
118 (defgeneric generalizer-equal-hash-key (generic-function generalizer))
119 (defmethod generalizer-equal-hash-key
120 ((gf specializable-generic-function) (g class))
121 (sb-pcl::class-wrapper g))
123 (defun first-arg-only-special-case (gf)
124 (let ((arg-info (sb-pcl::gf-arg-info gf)))
125 (and (slot-value gf 'single-arg-cacheing-p)
126 (>= (sb-pcl::arg-info-number-required arg-info) 1)
127 (every (lambda (x) (eql x t))
128 (cdr (sb-pcl::arg-info-metatypes arg-info))))))
130 ;;; FIXME: in some kind of order, the discriminating function needs to handle:
131 ;;; - argument count checking;
132 ;;; - DONE (in effective method) keyword argument validity;
133 ;;; - DONE flushing the emf cache on method addition/removal
134 ;;; - DONE (sort of, using wrappers/g-e-h-k) flushing the cache on class redefinition;
135 ;;; - cache thread-safety.
137 ;;; - interaction with TRACE et al.
138 (defmethod sb-mop:compute-discriminating-function ((gf specializable-generic-function))
140 ((not (slot-value gf 'cacheingp))
142 (let ((generalizers (mapcar (lambda (x) (generalizer-of-using-class gf x))
144 (slow-method-lookup-and-call gf args generalizers))))
145 ((first-arg-only-special-case gf)
147 (let* ((g (generalizer-of-using-class gf (car args)))
148 (k (generalizer-equal-hash-key gf g))
149 (emfun (gethash k (emf-table gf) nil)))
151 (sb-pcl::invoke-emf emfun args)
152 (slow-method-lookup-and-call
153 gf args (cons g (mapcar (lambda (x) (generalizer-of-using-class gf x))
154 (cdr (required-portion gf args)))))))))
157 (let* ((generalizers (mapcar (lambda (x) (generalizer-of-using-class gf x))
158 (required-portion gf args)))
159 (keys (mapcar (lambda (x) (generalizer-equal-hash-key gf x)) generalizers))
160 (emfun (gethash keys (emf-table gf) nil)))
162 (sb-pcl::invoke-emf emfun args)
163 (slow-method-lookup-and-call gf args generalizers)))))))
165 (defmethod reinitialize-instance :after ((gf specializable-generic-function) &key)
166 (clrhash (emf-table gf)))
168 (defun slow-method-lookup (gf args generalizers)
169 (multiple-value-bind (applicable-methods definitivep)
170 (compute-applicable-methods-using-generalizers gf generalizers)
172 (setf applicable-methods (compute-applicable-methods gf args)))
173 (values (compute-effective-method-function gf applicable-methods)
176 (defun slow-method-lookup-and-call (gf args generalizers)
177 (multiple-value-bind (emf cacheablep)
178 (slow-method-lookup gf args generalizers)
180 (let ((keys (mapcar (lambda (x) (generalizer-equal-hash-key gf x)) generalizers)))
181 (if (first-arg-only-special-case gf)
182 (setf (gethash (car keys) (emf-table gf)) emf)
183 (setf (gethash keys (emf-table gf)) emf))))
184 (sb-pcl::invoke-emf emf args)))
186 (defun compute-effective-method-function (gf methods)
188 (lambda (&rest args) (apply #'no-applicable-method gf args))
189 (let* ((mc (sb-mop:generic-function-method-combination gf))
190 (sb-pcl::*applicable-methods* methods)
191 (em (sb-mop:compute-effective-method gf mc methods)))
192 (sb-pcl::make-effective-method-function gf em))))
194 ;; new, not in closette
195 (defgeneric generalizer-of-using-class (generic-function object))
196 (defmethod generalizer-of-using-class ((generic-function specializable-generic-function) object)
199 (defgeneric specializer-accepts-generalizer-p (gf specializer generalizer))
200 (defmethod specializer-accepts-generalizer-p
201 ((gf specializable-generic-function) (specializer class) (generalizer class))
202 (if (subtypep generalizer specializer)
205 (defmethod specializer-accepts-generalizer-p
206 ((gf specializable-generic-function) (specializer sb-mop:eql-specializer) (generalizer class))
207 (if (eq generalizer (class-of (sb-mop:eql-specializer-object specializer)))
211 (defgeneric compute-applicable-methods-using-generalizers (gf generalizers))
212 (defmethod compute-applicable-methods-using-generalizers
213 ((gf specializable-generic-function) generalizers)
214 ;; differs from closette
215 (let ((result-definitive-p t))
216 (flet ((filter (method)
218 (multiple-value-bind (acceptsp definitivep)
219 (specializer-accepts-generalizer-p gf s g)
221 (setf result-definitive-p nil))
223 (sb-mop:method-specializers method) generalizers))
225 (method-more-specific-p gf m1 m2 generalizers)))
228 (copy-list (remove-if-not #'filter (sb-mop:generic-function-methods gf)))
230 result-definitive-p))))
232 ;; new, not in closette
233 (defgeneric specializer-accepts-p (specializer object))
234 (defmethod specializer-accepts-p ((specializer class) object)
235 (typep object specializer))
236 (defmethod specializer-accepts-p ((specializer sb-mop:eql-specializer) object)
237 (eq object (sb-mop:eql-specializer-object specializer)))
239 (defmethod compute-applicable-methods
240 ((gf specializable-generic-function) arguments)
241 ;; new, not in closette
244 (remove-if-not #'(lambda (method)
245 (every #'specializer-accepts-p
246 (sb-mop:method-specializers method)
248 (sb-mop:generic-function-methods gf)))
249 (let ((generalizers (mapcar (lambda (x) (generalizer-of-using-class gf x))
250 (required-portion gf arguments))))
252 (method-more-specific-p gf m1 m2 generalizers)))))
254 (defun method-more-specific-p (gf method1 method2 generalizers)
255 ;; FIXME: argument precedence order
257 (mapc #'(lambda (spec1 spec2 generalizer)
258 (ecase (specializer< gf spec1 spec2 generalizer)
261 ((nil > /=) (return nil))))
262 (sb-mop:method-specializers method1)
263 (sb-mop:method-specializers method2)
267 ;; new, not in closette
268 (defgeneric specializer< (gf s1 s2 generalizer))
269 (defmethod specializer<
270 ((gf specializable-generic-function) (s1 class) (s2 class) (generalizer class))
273 (let ((cpl (sb-mop:class-precedence-list generalizer)))
274 (if (find s2 (cdr (member s1 cpl)))
277 (defmethod specializer<
278 ((gf specializable-generic-function) (s1 sb-mop:eql-specializer) (s2 sb-mop:eql-specializer) generalizer)
279 (declare (ignore generalizer))
280 (if (eq (sb-mop:eql-specializer-object s1) (sb-mop:eql-specializer-object s2))
283 (defmethod specializer< ((gf specializable-generic-function) (s1 sb-mop:eql-specializer) (s2 class) generalizer)
284 (declare (ignore generalizer))
286 (defmethod specializer< ((gf specializable-generic-function) (c1 class) (c2 sb-mop:eql-specializer) generalizer)
287 (declare (ignore generalizer))