src/pcl/boot.lisp

   1 ;;;; This software is part of the SBCL system. See the README file for
   2 ;;;; more information.
   3
   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
   8 ;;;; information.
   9
  10 ;;;; copyright information from original PCL sources:
  11 ;;;;
  12 ;;;; Copyright (c) 1985, 1986, 1987, 1988, 1989, 1990 Xerox Corporation.
  13 ;;;; All rights reserved.
  14 ;;;;
  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
  18 ;;;; control laws.
  19 ;;;;
  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
  22 ;;;; specification.
  23
  24 (in-package "SB-PCL")
  25 \f
  26 #|
  27
  28 The CommonLoops evaluator is meta-circular.
  29
  30 Most of the code in PCL is methods on generic functions, including
  31 most of the code that actually implements generic functions and method
  32 lookup.
  33
  34 So, we have a classic bootstrapping problem. The solution to this is
  35 to first get a cheap implementation of generic functions running,
  36 these are called early generic functions. These early generic
  37 functions and the corresponding early methods and early method lookup
  38 are used to get enough of the system running that it is possible to
  39 create real generic functions and methods and implement real method
  40 lookup. At that point (done in the file FIXUP) the function
  41 !FIX-EARLY-GENERIC-FUNCTIONS is called to convert all the early generic
  42 functions to real generic functions.
  43
  44 The cheap generic functions are built using the same
  45 FUNCALLABLE-INSTANCE objects that real generic functions are made out of.
  46 This means that as PCL is being bootstrapped, the cheap generic
  47 function objects which are being created are the same objects which
  48 will later be real generic functions. This is good because:
  49   - we don't cons garbage structure, and
  50   - we can keep pointers to the cheap generic function objects
  51     during booting because those pointers will still point to
  52     the right object after the generic functions are all fixed up.
  53
  54 This file defines the DEFMETHOD macro and the mechanism used to expand
  55 it. This includes the mechanism for processing the body of a method.
  56 DEFMETHOD basically expands into a call to LOAD-DEFMETHOD, which
  57 basically calls ADD-METHOD to add the method to the generic function.
  58 These expansions can be loaded either during bootstrapping or when PCL
  59 is fully up and running.
  60
  61 An important effect of this arrangement is it means we can compile
  62 files with DEFMETHOD forms in them in a completely running PCL, but
  63 then load those files back in during bootstrapping. This makes
  64 development easier. It also means there is only one set of code for
  65 processing DEFMETHOD. Bootstrapping works by being sure to have
  66 LOAD-METHOD be careful to call only primitives which work during
  67 bootstrapping.
  68
  69 |#
  70
  71 ;;; FIXME: As of sbcl-0.6.9.10, PCL still uses this nonstandard type
  72 ;;; of declaration internally. It would be good to figure out how to
  73 ;;; get rid of it, or failing that, (1) document why it's needed and
  74 ;;; (2) use a private symbol with a forbidding name which suggests
  75 ;;; it's not to be messed with by the user (e.g. SB-PCL:%CLASS)
  76 ;;; instead of the too-inviting CLASS. (I tried just deleting the
  77 ;;; declarations in MAKE-METHOD-LAMBDA-INTERNAL ca. sbcl-0.6.9.10, but
  78 ;;; then things break.)
  79 (declaim (declaration class))
  80
  81 (declaim (notinline make-a-method
  82                     add-named-method
  83                     ensure-generic-function-using-class
  84                     add-method
  85                     remove-method))
  86
  87 (defvar *!early-functions*
  88         '((make-a-method early-make-a-method
  89                          real-make-a-method)
  90           (add-named-method early-add-named-method
  91                             real-add-named-method)
  92           ))
  93
  94 ;;; For each of the early functions, arrange to have it point to its
  95 ;;; early definition. Do this in a way that makes sure that if we
  96 ;;; redefine one of the early definitions the redefinition will take
  97 ;;; effect. This makes development easier.
  98 (dolist (fns *!early-functions*)
  99   (let ((name (car fns))
 100         (early-name (cadr fns)))
 101     (setf (gdefinition name)
 102             (set-fun-name
 103              (lambda (&rest args)
 104                (apply (fdefinition early-name) args))
 105              name))))
 106
 107 ;;; *!GENERIC-FUNCTION-FIXUPS* is used by !FIX-EARLY-GENERIC-FUNCTIONS
 108 ;;; to convert the few functions in the bootstrap which are supposed
 109 ;;; to be generic functions but can't be early on.
 110 (defvar *!generic-function-fixups*
 111   '((add-method
 112      ((generic-function method)  ;lambda-list
 113       (standard-generic-function method) ;specializers
 114       real-add-method))          ;method-function
 115     (remove-method
 116      ((generic-function method)
 117       (standard-generic-function method)
 118       real-remove-method))
 119     (get-method
 120      ((generic-function qualifiers specializers &optional (errorp t))
 121       (standard-generic-function t t)
 122       real-get-method))
 123     (ensure-generic-function-using-class
 124      ((generic-function fun-name
 125                         &key generic-function-class environment
 126                         &allow-other-keys)
 127       (generic-function t)
 128       real-ensure-gf-using-class--generic-function)
 129      ((generic-function fun-name
 130                         &key generic-function-class environment
 131                         &allow-other-keys)
 132       (null t)
 133       real-ensure-gf-using-class--null))
 134     (make-method-lambda
 135      ((proto-generic-function proto-method lambda-expression environment)
 136       (standard-generic-function standard-method t t)
 137       real-make-method-lambda))
 138     (make-method-initargs-form
 139      ((proto-generic-function proto-method
 140                               lambda-expression
 141                               lambda-list environment)
 142       (standard-generic-function standard-method t t t)
 143       real-make-method-initargs-form))
 144     (compute-effective-method
 145      ((generic-function combin applicable-methods)
 146       (generic-function standard-method-combination t)
 147       standard-compute-effective-method))))
 148 \f
 149 (defmacro defgeneric (fun-name lambda-list &body options)
 150   (declare (type list lambda-list))
 151   (unless (legal-fun-name-p fun-name)
 152     (error 'simple-program-error
 153            :format-control "illegal generic function name ~S"
 154            :format-arguments (list fun-name)))
 155   (check-gf-lambda-list lambda-list)
 156   (let ((initargs ())
 157         (methods ()))
 158     (flet ((duplicate-option (name)
 159              (error 'simple-program-error
 160                     :format-control "The option ~S appears more than once."
 161                     :format-arguments (list name)))
 162            (expand-method-definition (qab) ; QAB = qualifiers, arglist, body
 163              (let* ((arglist-pos (position-if #'listp qab))
 164                     (arglist (elt qab arglist-pos))
 165                     (qualifiers (subseq qab 0 arglist-pos))
 166                     (body (nthcdr (1+ arglist-pos) qab)))
 167                `(push (defmethod ,fun-name ,@qualifiers ,arglist ,@body)
 168                       (generic-function-initial-methods (fdefinition ',fun-name))))))
 169       (macrolet ((initarg (key) `(getf initargs ,key)))
 170         (dolist (option options)
 171           (let ((car-option (car option)))
 172             (case car-option
 173               (declare
 174                (when (and
 175                       (consp (cadr option))
 176                       (member (first (cadr option))
 177                               ;; FIXME: this list is slightly weird.
 178                               ;; ANSI (on the DEFGENERIC page) in one
 179                               ;; place allows only OPTIMIZE; in
 180                               ;; another place gives this list of
 181                               ;; disallowed declaration specifiers.
 182                               ;; This seems to be the only place where
 183                               ;; the FUNCTION declaration is
 184                               ;; mentioned; TYPE seems to be missing.
 185                               ;; Very strange.  -- CSR, 2002-10-21
 186                               '(declaration ftype function
 187                                 inline notinline special)))
 188                  (error 'simple-program-error
 189                         :format-control "The declaration specifier ~S ~
 190                                          is not allowed inside DEFGENERIC."
 191                         :format-arguments (list (cadr option))))
 192                (push (cadr option) (initarg :declarations)))
 193               (:method-combination
 194                (when (initarg car-option)
 195                  (duplicate-option car-option))
 196                (unless (symbolp (cadr option))
 197                  (error 'simple-program-error
 198                         :format-control "METHOD-COMBINATION name not a ~
 199                                          symbol: ~S"
 200                         :format-arguments (list (cadr option))))
 201                (setf (initarg car-option)
 202                      `',(cdr option)))
 203               (:argument-precedence-order
 204                (let* ((required (parse-lambda-list lambda-list))
 205                       (supplied (cdr option)))
 206                  (unless (= (length required) (length supplied))
 207                    (error 'simple-program-error
 208                           :format-control "argument count discrepancy in ~
 209                                            :ARGUMENT-PRECEDENCE-ORDER clause."
 210                           :format-arguments nil))
 211                  (when (set-difference required supplied)
 212                    (error 'simple-program-error
 213                           :format-control "unequal sets for ~
 214                                            :ARGUMENT-PRECEDENCE-ORDER clause: ~
 215                                            ~S and ~S"
 216                           :format-arguments (list required supplied)))
 217                  (setf (initarg car-option)
 218                        `',(cdr option))))
 219               ((:documentation :generic-function-class :method-class)
 220                (unless (proper-list-of-length-p option 2)
 221                  (error "bad list length for ~S" option))
 222                (if (initarg car-option)
 223                    (duplicate-option car-option)
 224                    (setf (initarg car-option) `',(cadr option))))
 225               (:method
 226                (push (cdr option) methods))
 227               (t
 228                ;; ANSI requires that unsupported things must get a
 229                ;; PROGRAM-ERROR.
 230                (error 'simple-program-error
 231                       :format-control "unsupported option ~S"
 232                       :format-arguments (list option))))))
 233
 234         (when (initarg :declarations)
 235           (setf (initarg :declarations)
 236                 `',(initarg :declarations))))
 237       `(progn
 238          (eval-when (:compile-toplevel :load-toplevel :execute)
 239            (compile-or-load-defgeneric ',fun-name))
 240          (load-defgeneric ',fun-name ',lambda-list ,@initargs)
 241         ,@(mapcar #'expand-method-definition methods)
 242         (fdefinition ',fun-name)))))
 243
 244 (defun compile-or-load-defgeneric (fun-name)
 245   (proclaim-as-fun-name fun-name)
 246   (note-name-defined fun-name :function)
 247   (unless (eq (info :function :where-from fun-name) :declared)
 248     (setf (info :function :where-from fun-name) :defined)
 249     (setf (info :function :type fun-name)
 250           (specifier-type 'function))))
 251
 252 (defun load-defgeneric (fun-name lambda-list &rest initargs)
 253   (when (fboundp fun-name)
 254     (style-warn "redefining ~S in DEFGENERIC" fun-name)
 255     (let ((fun (fdefinition fun-name)))
 256       (when (generic-function-p fun)
 257         (loop for method in (generic-function-initial-methods fun)
 258               do (remove-method fun method))
 259         (setf (generic-function-initial-methods fun) '()))))
 260   (apply #'ensure-generic-function
 261          fun-name
 262          :lambda-list lambda-list
 263          :definition-source `((defgeneric ,fun-name) ,*load-pathname*)
 264          initargs))
 265
 266 (define-condition generic-function-lambda-list-error
 267     (reference-condition simple-program-error)
 268   ()
 269   (:default-initargs :references (list '(:ansi-cl :section (3 4 2)))))
 270
 271 (defun check-gf-lambda-list (lambda-list)
 272   (flet ((ensure (arg ok)
 273            (unless ok
 274              (error 'generic-function-lambda-list-error
 275                     :format-control
 276                     "~@<invalid ~S ~_in the generic function lambda list ~S~:>"
 277                     :format-arguments (list arg lambda-list)))))
 278     (multiple-value-bind (required optional restp rest keyp keys allowp
 279                           auxp aux morep more-context more-count)
 280         (parse-lambda-list lambda-list)
 281       (declare (ignore required)) ; since they're no different in a gf ll
 282       (declare (ignore restp rest)) ; since they're no different in a gf ll
 283       (declare (ignore allowp)) ; since &ALLOW-OTHER-KEYS is fine either way
 284       (declare (ignore aux)) ; since we require AUXP=NIL
 285       (declare (ignore more-context more-count)) ; safely ignored unless MOREP
 286       ;; no defaults allowed for &OPTIONAL arguments
 287       (dolist (i optional)
 288         (ensure i (or (symbolp i)
 289                       (and (consp i) (symbolp (car i)) (null (cdr i))))))
 290       ;; no defaults allowed for &KEY arguments
 291       (when keyp
 292         (dolist (i keys)
 293           (ensure i (or (symbolp i)
 294                         (and (consp i)
 295                              (or (symbolp (car i))
 296                                  (and (consp (car i))
 297                                       (symbolp (caar i))
 298                                       (symbolp (cadar i))
 299                                       (null (cddar i))))
 300                              (null (cdr i)))))))
 301       ;; no &AUX allowed
 302       (when auxp
 303         (error "&AUX is not allowed in a generic function lambda list: ~S"
 304                lambda-list))
 305       ;; Oh, *puhlease*... not specifically as per section 3.4.2 of
 306       ;; the ANSI spec, but the CMU CL &MORE extension does not
 307       ;; belong here!
 308       (aver (not morep)))))
 309 \f
 310 (defmacro defmethod (&rest args &environment env)
 311   (multiple-value-bind (name qualifiers lambda-list body)
 312       (parse-defmethod args)
 313     (multiple-value-bind (proto-gf proto-method)
 314         (prototypes-for-make-method-lambda name)
 315       (expand-defmethod name
 316                         proto-gf
 317                         proto-method
 318                         qualifiers
 319                         lambda-list
 320                         body
 321                         env))))
 322
 323 (defun prototypes-for-make-method-lambda (name)
 324   (if (not (eq *boot-state* 'complete))
 325       (values nil nil)
 326       (let ((gf? (and (gboundp name)
 327                       (gdefinition name))))
 328         (if (or (null gf?)
 329                 (not (generic-function-p gf?)))
 330             (values (class-prototype (find-class 'standard-generic-function))
 331                     (class-prototype (find-class 'standard-method)))
 332             (values gf?
 333                     (class-prototype (or (generic-function-method-class gf?)
 334                                          (find-class 'standard-method))))))))
 335
 336 ;;; Take a name which is either a generic function name or a list specifying
 337 ;;; a SETF generic function (like: (SETF <generic-function-name>)). Return
 338 ;;; the prototype instance of the method-class for that generic function.
 339 ;;;
 340 ;;; If there is no generic function by that name, this returns the
 341 ;;; default value, the prototype instance of the class
 342 ;;; STANDARD-METHOD. This default value is also returned if the spec
 343 ;;; names an ordinary function or even a macro. In effect, this leaves
 344 ;;; the signalling of the appropriate error until load time.
 345 ;;;
 346 ;;; Note: During bootstrapping, this function is allowed to return NIL.
 347 (defun method-prototype-for-gf (name)
 348   (let ((gf? (and (gboundp name)
 349                   (gdefinition name))))
 350     (cond ((neq *boot-state* 'complete) nil)
 351           ((or (null gf?)
 352                (not (generic-function-p gf?)))          ; Someone else MIGHT
 353                                                         ; error at load time.
 354            (class-prototype (find-class 'standard-method)))
 355           (t
 356             (class-prototype (or (generic-function-method-class gf?)
 357                                  (find-class 'standard-method)))))))
 358 \f
 359 (defun expand-defmethod (name
 360                          proto-gf
 361                          proto-method
 362                          qualifiers
 363                          lambda-list
 364                          body
 365                          env)
 366   (multiple-value-bind (method-lambda unspecialized-lambda-list specializers)
 367       (add-method-declarations name qualifiers lambda-list body env)
 368     (multiple-value-bind (method-function-lambda initargs)
 369         (make-method-lambda proto-gf proto-method method-lambda env)
 370       (let ((initargs-form (make-method-initargs-form proto-gf
 371                                                       proto-method
 372                                                       method-function-lambda
 373                                                       initargs
 374                                                       env)))
 375         `(progn
 376           ;; Note: We could DECLAIM the ftype of the generic function
 377           ;; here, since ANSI specifies that we create it if it does
 378           ;; not exist. However, I chose not to, because I think it's
 379           ;; more useful to support a style of programming where every
 380           ;; generic function has an explicit DEFGENERIC and any typos
 381           ;; in DEFMETHODs are warned about. Otherwise
 382           ;;
 383           ;;   (DEFGENERIC FOO-BAR-BLETCH ((X T)))
 384           ;;   (DEFMETHOD FOO-BAR-BLETCH ((X HASH-TABLE)) ..)
 385           ;;   (DEFMETHOD FOO-BRA-BLETCH ((X SIMPLE-VECTOR)) ..)
 386           ;;   (DEFMETHOD FOO-BAR-BLETCH ((X VECTOR)) ..)
 387           ;;   (DEFMETHOD FOO-BAR-BLETCH ((X ARRAY)) ..)
 388           ;;   (DEFMETHOD FOO-BAR-BLETCH ((X LIST)) ..)
 389           ;;
 390           ;; compiles without raising an error and runs without
 391           ;; raising an error (since SIMPLE-VECTOR cases fall through
 392           ;; to VECTOR) but still doesn't do what was intended. I hate
 393           ;; that kind of bug (code which silently gives the wrong
 394           ;; answer), so we don't do a DECLAIM here. -- WHN 20000229
 395           ,(make-defmethod-form name qualifiers specializers
 396                                 unspecialized-lambda-list
 397                                 (if proto-method
 398                                     (class-name (class-of proto-method))
 399                                     'standard-method)
 400                                 initargs-form
 401                                 (getf (getf initargs :plist)
 402                                       :pv-table-symbol)))))))
 403
 404 (defun interned-symbol-p (x)
 405   (and (symbolp x) (symbol-package x)))
 406
 407 (defun make-defmethod-form (name qualifiers specializers
 408                                  unspecialized-lambda-list method-class-name
 409                                  initargs-form &optional pv-table-symbol)
 410   (let (fn
 411         fn-lambda)
 412     (if (and (interned-symbol-p (fun-name-block-name name))
 413              (every #'interned-symbol-p qualifiers)
 414              (every (lambda (s)
 415                       (if (consp s)
 416                           (and (eq (car s) 'eql)
 417                                (constantp (cadr s))
 418                                (let ((sv (eval (cadr s))))
 419                                  (or (interned-symbol-p sv)
 420                                      (integerp sv)
 421                                      (and (characterp sv)
 422                                           (standard-char-p sv)))))
 423                           (interned-symbol-p s)))
 424                     specializers)
 425              (consp initargs-form)
 426              (eq (car initargs-form) 'list*)
 427              (memq (cadr initargs-form) '(:function :fast-function))
 428              (consp (setq fn (caddr initargs-form)))
 429              (eq (car fn) 'function)
 430              (consp (setq fn-lambda (cadr fn)))
 431              (eq (car fn-lambda) 'lambda))
 432         (let* ((specls (mapcar (lambda (specl)
 433                                  (if (consp specl)
 434                                      `(,(car specl) ,(eval (cadr specl)))
 435                                    specl))
 436                                specializers))
 437                (mname `(,(if (eq (cadr initargs-form) :function)
 438                              'slow-method 'fast-method)
 439                         ,name ,@qualifiers ,specls)))
 440           `(progn
 441              (defun ,mname ,(cadr fn-lambda)
 442                ,@(cddr fn-lambda))
 443              ,(make-defmethod-form-internal
 444                name qualifiers `',specls
 445                unspecialized-lambda-list method-class-name
 446                `(list* ,(cadr initargs-form)
 447                        #',mname
 448                        ,@(cdddr initargs-form))
 449                pv-table-symbol)))
 450         (make-defmethod-form-internal
 451          name qualifiers
 452          `(list ,@(mapcar (lambda (specializer)
 453                             (if (consp specializer)
 454                                 ``(,',(car specializer)
 455                                       ,,(cadr specializer))
 456                                 `',specializer))
 457                           specializers))
 458          unspecialized-lambda-list
 459          method-class-name
 460          initargs-form
 461          pv-table-symbol))))
 462
 463 (defun make-defmethod-form-internal
 464     (name qualifiers specializers-form unspecialized-lambda-list
 465      method-class-name initargs-form &optional pv-table-symbol)
 466   `(load-defmethod
 467     ',method-class-name
 468     ',name
 469     ',qualifiers
 470     ,specializers-form
 471     ',unspecialized-lambda-list
 472     ,initargs-form
 473     ;; Paper over a bug in KCL by passing the cache-symbol here in
 474     ;; addition to in the list. FIXME: We should no longer need to do
 475     ;; this, since the CLOS code is now SBCL-specific, and doesn't
 476     ;; need to be ported to every buggy compiler in existence.
 477     ',pv-table-symbol))
 478
 479 (defmacro make-method-function (method-lambda &environment env)
 480   (make-method-function-internal method-lambda env))
 481
 482 (defun make-method-function-internal (method-lambda &optional env)
 483   (multiple-value-bind (proto-gf proto-method)
 484       (prototypes-for-make-method-lambda nil)
 485     (multiple-value-bind (method-function-lambda initargs)
 486         (make-method-lambda proto-gf proto-method method-lambda env)
 487       (make-method-initargs-form proto-gf
 488                                  proto-method
 489                                  method-function-lambda
 490                                  initargs
 491                                  env))))
 492
 493 (defun add-method-declarations (name qualifiers lambda-list body env)
 494   (declare (ignore env))
 495   (multiple-value-bind (parameters unspecialized-lambda-list specializers)
 496       (parse-specialized-lambda-list lambda-list)
 497     (multiple-value-bind (real-body declarations documentation)
 498         (parse-body body)
 499       (values `(lambda ,unspecialized-lambda-list
 500                  ,@(when documentation `(,documentation))
 501                  ;; (Old PCL code used a somewhat different style of
 502                  ;; list for %METHOD-NAME values. Our names use
 503                  ;; ,@QUALIFIERS instead of ,QUALIFIERS so that the
 504                  ;; method names look more like what you see in a
 505                  ;; DEFMETHOD form.)
 506                  ;;
 507                  ;; FIXME: As of sbcl-0.7.0.6, code elsewhere, at
 508                  ;; least the code to set up named BLOCKs around the
 509                  ;; bodies of methods, depends on the function's base
 510                  ;; name being the first element of the %METHOD-NAME
 511                  ;; list. It would be good to remove this dependency,
 512                  ;; perhaps by building the BLOCK here, or by using
 513                  ;; another declaration (e.g. %BLOCK-NAME), so that
 514                  ;; our method debug names are free to have any format,
 515                  ;; e.g. (:METHOD PRINT-OBJECT :AROUND (CLOWN T)).
 516                  ;;
 517                  ;; Further, as of sbcl-0.7.9.10, the code to
 518                  ;; implement NO-NEXT-METHOD is coupled to the form of
 519                  ;; this declaration; see the definition of
 520                  ;; CALL-NO-NEXT-METHOD (and the passing of
 521                  ;; METHOD-NAME-DECLARATION arguments around the
 522                  ;; various CALL-NEXT-METHOD logic).
 523                  (declare (%method-name (,name
 524                                          ,@qualifiers
 525                                          ,specializers)))
 526                  (declare (%method-lambda-list ,@lambda-list))
 527                  ,@declarations
 528                  ,@real-body)
 529               unspecialized-lambda-list specializers))))
 530
 531 (defun real-make-method-initargs-form (proto-gf proto-method
 532                                        method-lambda initargs env)
 533   (declare (ignore proto-gf proto-method))
 534   (unless (and (consp method-lambda)
 535                (eq (car method-lambda) 'lambda))
 536     (error "The METHOD-LAMBDA argument to MAKE-METHOD-FUNCTION, ~S, ~
 537             is not a lambda form."
 538            method-lambda))
 539   (make-method-initargs-form-internal method-lambda initargs env))
 540
 541 (unless (fboundp 'make-method-initargs-form)
 542   (setf (gdefinition 'make-method-initargs-form)
 543         (symbol-function 'real-make-method-initargs-form)))
 544
 545 (defun real-make-method-lambda (proto-gf proto-method method-lambda env)
 546   (declare (ignore proto-gf proto-method))
 547   (make-method-lambda-internal method-lambda env))
 548
 549 ;;; a helper function for creating Python-friendly type declarations
 550 ;;; in DEFMETHOD forms
 551 (defun parameter-specializer-declaration-in-defmethod (parameter specializer)
 552   (cond ((and (consp specializer)
 553               (eq (car specializer) 'eql))
 554          ;; KLUDGE: ANSI, in its wisdom, says that
 555          ;; EQL-SPECIALIZER-FORMs in EQL specializers are evaluated at
 556          ;; DEFMETHOD expansion time. Thus, although one might think
 557          ;; that in
 558          ;;   (DEFMETHOD FOO ((X PACKAGE)
 559          ;;                   (Y (EQL 12))
 560          ;;      ..))
 561          ;; the PACKAGE and (EQL 12) forms are both parallel type
 562          ;; names, they're not, as is made clear when you do
 563          ;;   (DEFMETHOD FOO ((X PACKAGE)
 564          ;;                   (Y (EQL 'BAR)))
 565          ;;     ..)
 566          ;; where Y needs to be a symbol named "BAR", not some cons
 567          ;; made by (CONS 'QUOTE 'BAR). I.e. when the
 568          ;; EQL-SPECIALIZER-FORM is (EQL 'X), it requires an argument
 569          ;; to be of type (EQL X). It'd be easy to transform one to
 570          ;; the other, but it'd be somewhat messier to do so while
 571          ;; ensuring that the EQL-SPECIALIZER-FORM is only EVAL'd
 572          ;; once. (The new code wouldn't be messy, but it'd require a
 573          ;; big transformation of the old code.) So instead we punt.
 574          ;; -- WHN 20000610
 575          '(ignorable))
 576         ((member specializer
 577                  ;; KLUDGE: For some low-level implementation
 578                  ;; classes, perhaps because of some problems related
 579                  ;; to the incomplete integration of PCL into SBCL's
 580                  ;; type system, some specializer classes can't be
 581                  ;; declared as argument types. E.g.
 582                  ;;   (DEFMETHOD FOO ((X SLOT-OBJECT))
 583                  ;;     (DECLARE (TYPE SLOT-OBJECT X))
 584                  ;;     ..)
 585                  ;; loses when
 586                  ;;   (DEFSTRUCT BAR A B)
 587                  ;;   (FOO (MAKE-BAR))
 588                  ;; perhaps because of the way that STRUCTURE-OBJECT
 589                  ;; inherits both from SLOT-OBJECT and from
 590                  ;; SB-KERNEL:INSTANCE. In an effort to sweep such
 591                  ;; problems under the rug, we exclude these problem
 592                  ;; cases by blacklisting them here. -- WHN 2001-01-19
 593                  '(slot-object))
 594          '(ignorable))
 595         ((not (eq *boot-state* 'complete))
 596          ;; KLUDGE: PCL, in its wisdom, sometimes calls methods with
 597          ;; types which don't match their specializers. (Specifically,
 598          ;; it calls ENSURE-CLASS-USING-CLASS (T NULL) with a non-NULL
 599          ;; second argument.) Hopefully it only does this kind of
 600          ;; weirdness when bootstrapping.. -- WHN 20000610
 601          '(ignorable))
 602         ((var-globally-special-p parameter)
 603          ;; KLUDGE: Don't declare types for global special variables
 604          ;; -- our rebinding magic for SETQ cases don't work right
 605          ;; there.
 606          ;;
 607          ;; FIXME: It would be better to detect the SETQ earlier and
 608          ;; skip declarations for specials only when needed, not
 609          ;; always.
 610          ;;
 611          ;; --NS 2004-10-14
 612          '(ignorable))
 613         (t
 614          ;; Otherwise, we can usually make Python very happy.
 615          (let ((type (info :type :kind specializer)))
 616            (ecase type
 617              ((:primitive) `(type ,specializer ,parameter))
 618              ((:instance nil)
 619               (let ((class (find-class specializer nil)))
 620                 (cond
 621                   (class
 622                    (if (typep class '(or built-in-class structure-class))
 623                        `(type ,specializer ,parameter)
 624                        ;; don't declare CLOS classes as parameters;
 625                        ;; it's too expensive.
 626                        '(ignorable)))
 627                   (t
 628                    ;; we can get here, and still not have a failure
 629                    ;; case, by doing MOP programming like (PROGN
 630                    ;; (ENSURE-CLASS 'FOO) (DEFMETHOD BAR ((X FOO))
 631                    ;; ...)).  Best to let the user know we haven't
 632                    ;; been able to extract enough information:
 633                    (style-warn
 634                     "~@<can't find type for presumed class ~S in ~S.~@:>"
 635                     specializer
 636                     'parameter-specializer-declaration-in-defmethod)
 637                    '(ignorable)))))
 638              ((:forthcoming-defclass-type) '(ignorable)))))))
 639
 640 (defun make-method-lambda-internal (method-lambda &optional env)
 641   (unless (and (consp method-lambda) (eq (car method-lambda) 'lambda))
 642     (error "The METHOD-LAMBDA argument to MAKE-METHOD-LAMBDA, ~S, ~
 643             is not a lambda form."
 644            method-lambda))
 645   (multiple-value-bind (real-body declarations documentation)
 646       (parse-body (cddr method-lambda))
 647     (let* ((name-decl (get-declaration '%method-name declarations))
 648            (sll-decl (get-declaration '%method-lambda-list declarations))
 649            (method-name (when (consp name-decl) (car name-decl)))
 650            (generic-function-name (when method-name (car method-name)))
 651            (specialized-lambda-list (or sll-decl (cadr method-lambda))))
 652       (multiple-value-bind (parameters lambda-list specializers)
 653           (parse-specialized-lambda-list specialized-lambda-list)
 654         (let* ((required-parameters
 655                 (mapcar (lambda (r s) (declare (ignore s)) r)
 656                         parameters
 657                         specializers))
 658                (slots (mapcar #'list required-parameters))
 659                (calls (list nil))
 660                (class-declarations
 661                 `(declare
 662                   ;; These declarations seem to be used by PCL to pass
 663                   ;; information to itself; when I tried to delete 'em
 664                   ;; ca. 0.6.10 it didn't work. I'm not sure how
 665                   ;; they work, but note the (VAR-DECLARATION '%CLASS ..)
 666                   ;; expression in CAN-OPTIMIZE-ACCESS1. -- WHN 2000-12-30
 667                   ,@(remove nil
 668                             (mapcar (lambda (a s) (and (symbolp s)
 669                                                        (neq s t)
 670                                                        `(%class ,a ,s)))
 671                                     parameters
 672                                     specializers))
 673                   ;; These TYPE declarations weren't in the original
 674                   ;; PCL code, but the Python compiler likes them a
 675                   ;; lot. (We're telling the compiler about our
 676                   ;; knowledge of specialized argument types so that
 677                   ;; it can avoid run-time type dispatch overhead,
 678                   ;; which can be a huge win for Python.)
 679                   ;;
 680                   ;; KLUDGE: when I tried moving these to
 681                   ;; ADD-METHOD-DECLARATIONS, things broke.  No idea
 682                   ;; why.  -- CSR, 2004-06-16
 683                   ,@(mapcar #'parameter-specializer-declaration-in-defmethod
 684                             parameters
 685                             specializers)))
 686                (method-lambda
 687                 ;; Remove the documentation string and insert the
 688                 ;; appropriate class declarations. The documentation
 689                 ;; string is removed to make it easy for us to insert
 690                 ;; new declarations later, they will just go after the
 691                 ;; CADR of the method lambda. The class declarations
 692                 ;; are inserted to communicate the class of the method's
 693                 ;; arguments to the code walk.
 694                 `(lambda ,lambda-list
 695                    ;; The default ignorability of method parameters
 696                    ;; doesn't seem to be specified by ANSI. PCL had
 697                    ;; them basically ignorable but was a little
 698                    ;; inconsistent. E.g. even though the two
 699                    ;; method definitions
 700                    ;;   (DEFMETHOD FOO ((X T) (Y T)) "Z")
 701                    ;;   (DEFMETHOD FOO ((X T) Y) "Z")
 702                    ;; are otherwise equivalent, PCL treated Y as
 703                    ;; ignorable in the first definition but not in the
 704                    ;; second definition. We make all required
 705                    ;; parameters ignorable as a way of systematizing
 706                    ;; the old PCL behavior. -- WHN 2000-11-24
 707                    (declare (ignorable ,@required-parameters))
 708                    ,class-declarations
 709                    ,@declarations
 710                    (block ,(fun-name-block-name generic-function-name)
 711                      ,@real-body)))
 712                (constant-value-p (and (null (cdr real-body))
 713                                       (constantp (car real-body))))
 714                (constant-value (and constant-value-p
 715                                     (eval (car real-body))))
 716                (plist (and constant-value-p
 717                            (or (typep constant-value
 718                                       '(or number character))
 719                                (and (symbolp constant-value)
 720                                     (symbol-package constant-value)))
 721                            (list :constant-value constant-value)))
 722                (applyp (dolist (p lambda-list nil)
 723                          (cond ((memq p '(&optional &rest &key))
 724                                 (return t))
 725                                ((eq p '&aux)
 726                                 (return nil))))))
 727           (multiple-value-bind
 728                 (walked-lambda call-next-method-p closurep
 729                                next-method-p-p setq-p)
 730               (walk-method-lambda method-lambda
 731                                   required-parameters
 732                                   env
 733                                   slots
 734                                   calls)
 735             (multiple-value-bind (walked-lambda-body
 736                                   walked-declarations
 737                                   walked-documentation)
 738                 (parse-body (cddr walked-lambda))
 739               (declare (ignore walked-documentation))
 740               (when (or next-method-p-p call-next-method-p)
 741                 (setq plist (list* :needs-next-methods-p t plist)))
 742               (when (some #'cdr slots)
 743                 (multiple-value-bind (slot-name-lists call-list)
 744                     (slot-name-lists-from-slots slots calls)
 745                   (let ((pv-table-symbol (make-symbol "pv-table")))
 746                     (setq plist
 747                           `(,@(when slot-name-lists
 748                                 `(:slot-name-lists ,slot-name-lists))
 749                               ,@(when call-list
 750                                   `(:call-list ,call-list))
 751                               :pv-table-symbol ,pv-table-symbol
 752                               ,@plist))
 753                     (setq walked-lambda-body
 754                           `((pv-binding (,required-parameters
 755                                          ,slot-name-lists
 756                                          ,pv-table-symbol)
 757                                         ,@walked-lambda-body))))))
 758               (when (and (memq '&key lambda-list)
 759                          (not (memq '&allow-other-keys lambda-list)))
 760                 (let ((aux (memq '&aux lambda-list)))
 761                 (setq lambda-list (nconc (ldiff lambda-list aux)
 762                                          (list '&allow-other-keys)
 763                                          aux))))
 764               (values `(lambda (.method-args. .next-methods.)
 765                          (simple-lexical-method-functions
 766                           (,lambda-list .method-args. .next-methods.
 767                                         :call-next-method-p
 768                                         ,call-next-method-p
 769                                         :next-method-p-p ,next-method-p-p
 770                                         :setq-p ,setq-p
 771                                         ;; we need to pass this along
 772                                         ;; so that NO-NEXT-METHOD can
 773                                         ;; be given a suitable METHOD
 774                                         ;; argument; we need the
 775                                         ;; QUALIFIERS and SPECIALIZERS
 776                                         ;; inside the declaration to
 777                                         ;; give to FIND-METHOD.
 778                                         :method-name-declaration ,name-decl
 779                                         :closurep ,closurep
 780                                         :applyp ,applyp)
 781                           ,@walked-declarations
 782                           ,@walked-lambda-body))
 783                       `(,@(when plist
 784                       `(:plist ,plist))
 785                           ,@(when documentation
 786                           `(:documentation ,documentation)))))))))))
 787
 788 (unless (fboundp 'make-method-lambda)
 789   (setf (gdefinition 'make-method-lambda)
 790         (symbol-function 'real-make-method-lambda)))
 791
 792 (defmacro simple-lexical-method-functions ((lambda-list
 793                                             method-args
 794                                             next-methods
 795                                             &rest lmf-options)
 796                                            &body body)
 797   `(progn
 798      ,method-args ,next-methods
 799      (bind-simple-lexical-method-macros (,method-args ,next-methods)
 800        (bind-lexical-method-functions (,@lmf-options)
 801          (bind-args (,lambda-list ,method-args)
 802            ,@body)))))
 803
 804 (defmacro fast-lexical-method-functions ((lambda-list
 805                                           next-method-call
 806                                           args
 807                                           rest-arg
 808                                           &rest lmf-options)
 809                                          &body body)
 810   `(bind-fast-lexical-method-macros (,args ,rest-arg ,next-method-call)
 811      (bind-lexical-method-functions (,@lmf-options)
 812        (bind-args (,(nthcdr (length args) lambda-list) ,rest-arg)
 813          ,@body))))
 814
 815 (defmacro bind-simple-lexical-method-macros ((method-args next-methods)
 816                                              &body body)
 817   `(macrolet ((call-next-method-bind (&body body)
 818                `(let ((.next-method. (car ,',next-methods))
 819                       (,',next-methods (cdr ,',next-methods)))
 820                  .next-method. ,',next-methods
 821                  ,@body))
 822               (call-next-method-body (method-name-declaration cnm-args)
 823                `(if .next-method.
 824                     (funcall (if (std-instance-p .next-method.)
 825                                  (method-function .next-method.)
 826                              .next-method.) ; for early methods
 827                              (or ,cnm-args ,',method-args)
 828                              ,',next-methods)
 829                     (apply #'call-no-next-method ',method-name-declaration
 830                             (or ,cnm-args ,',method-args))))
 831               (next-method-p-body ()
 832                `(not (null .next-method.)))
 833               (with-rebound-original-args ((call-next-method-p setq-p)
 834                                            &body body)
 835                 (declare (ignore call-next-method-p setq-p))
 836                 `(let () ,@body)))
 837     ,@body))
 838
 839 (defun call-no-next-method (method-name-declaration &rest args)
 840   (destructuring-bind (name) method-name-declaration
 841     (destructuring-bind (name &rest qualifiers-and-specializers) name
 842       ;; KLUDGE: inefficient traversal, but hey.  This should only
 843       ;; happen on the slow error path anyway.
 844       (let* ((qualifiers (butlast qualifiers-and-specializers))
 845              (specializers (car (last qualifiers-and-specializers)))
 846              (method (find-method (gdefinition name) qualifiers specializers)))
 847         (apply #'no-next-method
 848                (method-generic-function method)
 849                method
 850                args)))))
 851
 852 (defstruct (method-call (:copier nil))
 853   (function #'identity :type function)
 854   call-method-args)
 855
 856 #-sb-fluid (declaim (sb-ext:freeze-type method-call))
 857
 858 (defmacro invoke-method-call1 (function args cm-args)
 859   `(let ((.function. ,function)
 860          (.args. ,args)
 861          (.cm-args. ,cm-args))
 862      (if (and .cm-args. (null (cdr .cm-args.)))
 863          (funcall .function. .args. (car .cm-args.))
 864          (apply .function. .args. .cm-args.))))
 865
 866 (defmacro invoke-method-call (method-call restp &rest required-args+rest-arg)
 867   `(invoke-method-call1 (method-call-function ,method-call)
 868                         ,(if restp
 869                              `(list* ,@required-args+rest-arg)
 870                              `(list ,@required-args+rest-arg))
 871                         (method-call-call-method-args ,method-call)))
 872
 873 (defstruct (fast-method-call (:copier nil))
 874   (function #'identity :type function)
 875   pv-cell
 876   next-method-call
 877   arg-info)
 878
 879 #-sb-fluid (declaim (sb-ext:freeze-type fast-method-call))
 880
 881 (defmacro fmc-funcall (fn pv-cell next-method-call &rest args)
 882   `(funcall ,fn ,pv-cell ,next-method-call ,@args))
 883
 884 (defmacro invoke-fast-method-call (method-call &rest required-args+rest-arg)
 885   `(fmc-funcall (fast-method-call-function ,method-call)
 886                 (fast-method-call-pv-cell ,method-call)
 887                 (fast-method-call-next-method-call ,method-call)
 888                 ,@required-args+rest-arg))
 889
 890 (defstruct (fast-instance-boundp (:copier nil))
 891   (index 0 :type fixnum))
 892
 893 #-sb-fluid (declaim (sb-ext:freeze-type fast-instance-boundp))
 894
 895 (eval-when (:compile-toplevel :load-toplevel :execute)
 896   (defvar *allow-emf-call-tracing-p* nil)
 897   (defvar *enable-emf-call-tracing-p* #-sb-show nil #+sb-show t))
 898 \f
 899 ;;;; effective method functions
 900
 901 (defvar *emf-call-trace-size* 200)
 902 (defvar *emf-call-trace* nil)
 903 (defvar *emf-call-trace-index* 0)
 904
 905 ;;; This function was in the CMU CL version of PCL (ca Debian 2.4.8)
 906 ;;; without explanation. It appears to be intended for debugging, so
 907 ;;; it might be useful someday, so I haven't deleted it.
 908 ;;; But it isn't documented and isn't used for anything now, so
 909 ;;; I've conditionalized it out of the base system. -- WHN 19991213
 910 #+sb-show
 911 (defun show-emf-call-trace ()
 912   (when *emf-call-trace*
 913     (let ((j *emf-call-trace-index*)
 914           (*enable-emf-call-tracing-p* nil))
 915       (format t "~&(The oldest entries are printed first)~%")
 916       (dotimes-fixnum (i *emf-call-trace-size*)
 917         (let ((ct (aref *emf-call-trace* j)))
 918           (when ct (print ct)))
 919         (incf j)
 920         (when (= j *emf-call-trace-size*)
 921           (setq j 0))))))
 922
 923 (defun trace-emf-call-internal (emf format args)
 924   (unless *emf-call-trace*
 925     (setq *emf-call-trace* (make-array *emf-call-trace-size*)))
 926   (setf (aref *emf-call-trace* *emf-call-trace-index*)
 927         (list* emf format args))
 928   (incf *emf-call-trace-index*)
 929   (when (= *emf-call-trace-index* *emf-call-trace-size*)
 930     (setq *emf-call-trace-index* 0)))
 931
 932 (defmacro trace-emf-call (emf format args)
 933   (when *allow-emf-call-tracing-p*
 934     `(when *enable-emf-call-tracing-p*
 935        (trace-emf-call-internal ,emf ,format ,args))))
 936
 937 (defmacro invoke-effective-method-function-fast
 938     (emf restp &rest required-args+rest-arg)
 939   `(progn
 940      (trace-emf-call ,emf ,restp (list ,@required-args+rest-arg))
 941      (invoke-fast-method-call ,emf ,@required-args+rest-arg)))
 942
 943 (defmacro invoke-effective-method-function (emf restp
 944                                                 &rest required-args+rest-arg)
 945   (unless (constantp restp)
 946     (error "The RESTP argument is not constant."))
 947   ;; FIXME: The RESTP handling here is confusing and maybe slightly
 948   ;; broken if RESTP evaluates to a non-self-evaluating form. E.g. if
 949   ;;   (INVOKE-EFFECTIVE-METHOD-FUNCTION EMF '(ERROR "gotcha") ...)
 950   ;; then TRACE-EMF-CALL-CALL-INTERNAL might die on a gotcha error.
 951   (setq restp (eval restp))
 952   `(progn
 953      (trace-emf-call ,emf ,restp (list ,@required-args+rest-arg))
 954      (cond ((typep ,emf 'fast-method-call)
 955             (invoke-fast-method-call ,emf ,@required-args+rest-arg))
 956            ;; "What," you may wonder, "do these next two clauses do?"
 957            ;; In that case, you are not a PCL implementor, for they
 958            ;; considered this to be self-documenting.:-| Or CSR, for
 959            ;; that matter, since he can also figure it out by looking
 960            ;; at it without breaking stride. For the rest of us,
 961            ;; though: From what the code is doing with .SLOTS. and
 962            ;; whatnot, evidently it's implementing SLOT-VALUEish and
 963            ;; GET-SLOT-VALUEish things. Then we can reason backwards
 964            ;; and conclude that setting EMF to a FIXNUM is an
 965            ;; optimized way to represent these slot access operations.
 966            ,@(when (and (null restp) (= 1 (length required-args+rest-arg)))
 967                `(((typep ,emf 'fixnum)
 968                   (let* ((.slots. (get-slots-or-nil
 969                                    ,(car required-args+rest-arg)))
 970                          (value (when .slots. (clos-slots-ref .slots. ,emf))))
 971                     (if (eq value +slot-unbound+)
 972                         (slot-unbound-internal ,(car required-args+rest-arg)
 973                                                ,emf)
 974                         value)))))
 975            ,@(when (and (null restp) (= 2 (length required-args+rest-arg)))
 976                `(((typep ,emf 'fixnum)
 977                   (let ((.new-value. ,(car required-args+rest-arg))
 978                         (.slots. (get-slots-or-nil
 979                                   ,(cadr required-args+rest-arg))))
 980                     (when .slots.
 981                       (setf (clos-slots-ref .slots. ,emf) .new-value.))))))
 982            ;; (In cmucl-2.4.8 there was a commented-out third ,@(WHEN
 983            ;; ...) clause here to handle SLOT-BOUNDish stuff. Since
 984            ;; there was no explanation and presumably the code is 10+
 985            ;; years stale, I simply deleted it. -- WHN)
 986            (t
 987             (etypecase ,emf
 988               (method-call
 989                (invoke-method-call ,emf ,restp ,@required-args+rest-arg))
 990               (function
 991                ,(if restp
 992                     `(apply (the function ,emf) ,@required-args+rest-arg)
 993                     `(funcall (the function ,emf)
 994                               ,@required-args+rest-arg))))))))
 995
 996 (defun invoke-emf (emf args)
 997   (trace-emf-call emf t args)
 998   (etypecase emf
 999     (fast-method-call
1000      (let* ((arg-info (fast-method-call-arg-info emf))
1001             (restp (cdr arg-info))
1002             (nreq (car arg-info)))
1003        (if restp
1004            (let* ((rest-args (nthcdr nreq args))
1005                   (req-args (ldiff args rest-args)))
1006              (apply (fast-method-call-function emf)
1007                     (fast-method-call-pv-cell emf)
1008                     (fast-method-call-next-method-call emf)
1009                     (nconc req-args (list rest-args))))
1010            (cond ((null args)
1011                   (if (eql nreq 0)
1012                       (invoke-fast-method-call emf)
1013                       (error "wrong number of args")))
1014                  ((null (cdr args))
1015                   (if (eql nreq 1)
1016                       (invoke-fast-method-call emf (car args))
1017                       (error "wrong number of args")))
1018                  ((null (cddr args))
1019                   (if (eql nreq 2)
1020                       (invoke-fast-method-call emf (car args) (cadr args))
1021                       (error "wrong number of args")))
1022                  (t
1023                   (apply (fast-method-call-function emf)
1024                          (fast-method-call-pv-cell emf)
1025                          (fast-method-call-next-method-call emf)
1026                          args))))))
1027     (method-call
1028      (apply (method-call-function emf)
1029             args
1030             (method-call-call-method-args emf)))
1031     (fixnum
1032      (cond ((null args) (error "1 or 2 args were expected."))
1033            ((null (cdr args))
1034             (let* ((slots (get-slots (car args)))
1035                    (value (clos-slots-ref slots emf)))
1036               (if (eq value +slot-unbound+)
1037                   (slot-unbound-internal (car args) emf)
1038                   value)))
1039            ((null (cddr args))
1040              (setf (clos-slots-ref (get-slots (cadr args)) emf)
1041                    (car args)))
1042            (t (error "1 or 2 args were expected."))))
1043     (fast-instance-boundp
1044      (if (or (null args) (cdr args))
1045          (error "1 arg was expected.")
1046        (let ((slots (get-slots (car args))))
1047          (not (eq (clos-slots-ref slots
1048                                   (fast-instance-boundp-index emf))
1049                   +slot-unbound+)))))
1050     (function
1051      (apply emf args))))
1052 \f
1053 (defmacro bind-fast-lexical-method-macros ((args rest-arg next-method-call)
1054                                            &body body)
1055   (let* ((all-params (append args (when rest-arg (list rest-arg))))
1056          (rebindings (mapcar (lambda (x) (list x x)) all-params)))
1057     `(macrolet ((narrowed-emf (emf)
1058                  ;; INVOKE-EFFECTIVE-METHOD-FUNCTION has code in it to
1059                  ;; dispatch on the possibility that EMF might be of
1060                  ;; type FIXNUM (as an optimized representation of a
1061                  ;; slot accessor). But as far as I (WHN 2002-06-11)
1062                  ;; can tell, it's impossible for such a representation
1063                  ;; to end up as .NEXT-METHOD-CALL. By reassuring
1064                  ;; INVOKE-E-M-F that when called from this context
1065                  ;; it needn't worry about the FIXNUM case, we can
1066                  ;; keep those cases from being compiled, which is
1067                  ;; good both because it saves bytes and because it
1068                  ;; avoids annoying type mismatch compiler warnings.
1069                  ;;
1070                  ;; KLUDGE: In sbcl-0.7.4.29, the compiler's type
1071                  ;; system isn't smart enough about NOT and
1072                  ;; intersection types to benefit from a (NOT FIXNUM)
1073                  ;; declaration here. -- WHN 2002-06-12 (FIXME: maybe
1074                  ;; it is now... -- CSR, 2003-06-07)
1075                  ;;
1076                  ;; FIXME: Might the FUNCTION type be omittable here,
1077                  ;; leaving only METHOD-CALLs? Failing that, could this
1078                  ;; be documented somehow? (It'd be nice if the types
1079                  ;; involved could be understood without solving the
1080                  ;; halting problem.)
1081                  `(the (or function method-call fast-method-call)
1082                    ,emf))
1083                 (call-next-method-bind (&body body)
1084                  `(let () ,@body))
1085                 (call-next-method-body (method-name-declaration cnm-args)
1086                  `(if ,',next-method-call
1087                       ,(locally
1088                         ;; This declaration suppresses a "deleting
1089                         ;; unreachable code" note for the following IF
1090                         ;; when REST-ARG is NIL. It is not nice for
1091                         ;; debugging SBCL itself, but at least it
1092                         ;; keeps us from annoying users.
1093                         (declare (optimize (inhibit-warnings 3)))
1094                         (if (and (null ',rest-arg)
1095                                  (consp cnm-args)
1096                                  (eq (car cnm-args) 'list))
1097                             `(invoke-effective-method-function
1098                               (narrowed-emf ,',next-method-call)
1099                               nil
1100                               ,@(cdr cnm-args))
1101                             (let ((call `(invoke-effective-method-function
1102                                           (narrowed-emf ,',next-method-call)
1103                                           ,',(not (null rest-arg))
1104                                           ,@',args
1105                                           ,@',(when rest-arg `(,rest-arg)))))
1106                               `(if ,cnm-args
1107                                 (bind-args ((,@',args
1108                                              ,@',(when rest-arg
1109                                                        `(&rest ,rest-arg)))
1110                                             ,cnm-args)
1111                                  ,call)
1112                                 ,call))))
1113                       ,(locally
1114                         ;; As above, this declaration suppresses code
1115                         ;; deletion notes.
1116                         (declare (optimize (inhibit-warnings 3)))
1117                         (if (and (null ',rest-arg)
1118                                  (consp cnm-args)
1119                                  (eq (car cnm-args) 'list))
1120                             `(call-no-next-method ',method-name-declaration
1121                               ,@(cdr cnm-args))
1122                             `(call-no-next-method ',method-name-declaration
1123                               ,@',args
1124                               ,@',(when rest-arg
1125                                         `(,rest-arg)))))))
1126                 (next-method-p-body ()
1127                  `(not (null ,',next-method-call)))
1128                 (with-rebound-original-args ((cnm-p setq-p) &body body)
1129                   (if (or cnm-p setq-p)
1130                       `(let ,',rebindings
1131                         (declare (ignorable ,@',all-params))
1132                         ,@body)
1133                       `(let () ,@body))))
1134       ,@body)))
1135
1136 (defmacro bind-lexical-method-functions
1137     ((&key call-next-method-p next-method-p-p setq-p
1138            closurep applyp method-name-declaration)
1139      &body body)
1140   (cond ((and (null call-next-method-p) (null next-method-p-p)
1141               (null closurep) (null applyp) (null setq-p))
1142          `(let () ,@body))
1143         (t
1144          `(call-next-method-bind
1145             (flet (,@(and call-next-method-p
1146                           `((call-next-method (&rest cnm-args)
1147                              (call-next-method-body
1148                               ,method-name-declaration
1149                               cnm-args))))
1150                    ,@(and next-method-p-p
1151                           '((next-method-p ()
1152                              (next-method-p-body)))))
1153               (with-rebound-original-args (,call-next-method-p ,setq-p)
1154                 ,@body))))))
1155
1156 (defmacro bind-args ((lambda-list args) &body body)
1157   (let ((args-tail '.args-tail.)
1158         (key '.key.)
1159         (state 'required))
1160     (flet ((process-var (var)
1161              (if (memq var lambda-list-keywords)
1162                  (progn
1163                    (case var
1164                      (&optional       (setq state 'optional))
1165                      (&key            (setq state 'key))
1166                      (&allow-other-keys)
1167                      (&rest           (setq state 'rest))
1168                      (&aux            (setq state 'aux))
1169                      (otherwise
1170                       (error
1171                        "encountered the non-standard lambda list keyword ~S"
1172                        var)))
1173                    nil)
1174                  (case state
1175                    (required `((,var (pop ,args-tail))))
1176                    (optional (cond ((not (consp var))
1177                                     `((,var (when ,args-tail
1178                                               (pop ,args-tail)))))
1179                                    ((null (cddr var))
1180                                     `((,(car var) (if ,args-tail
1181                                                       (pop ,args-tail)
1182                                                       ,(cadr var)))))
1183                                    (t
1184                                     `((,(caddr var) ,args-tail)
1185                                       (,(car var) (if ,args-tail
1186                                                       (pop ,args-tail)
1187                                                       ,(cadr var)))))))
1188                    (rest `((,var ,args-tail)))
1189                    (key (cond ((not (consp var))
1190                                `((,var (car
1191                                         (get-key-arg-tail ,(keywordicate var)
1192                                                           ,args-tail)))))
1193                               ((null (cddr var))
1194                                (multiple-value-bind (keyword variable)
1195                                    (if (consp (car var))
1196                                        (values (caar var)
1197                                                (cadar var))
1198                                        (values (keywordicate (car var))
1199                                                (car var)))
1200                                  `((,key (get-key-arg-tail ',keyword
1201                                                            ,args-tail))
1202                                    (,variable (if ,key
1203                                                   (car ,key)
1204                                                   ,(cadr var))))))
1205                               (t
1206                                (multiple-value-bind (keyword variable)
1207                                    (if (consp (car var))
1208                                        (values (caar var)
1209                                                (cadar var))
1210                                        (values (keywordicate (car var))
1211                                                (car var)))
1212                                  `((,key (get-key-arg-tail ',keyword
1213                                                            ,args-tail))
1214                                    (,(caddr var) ,key)
1215                                    (,variable (if ,key
1216                                                   (car ,key)
1217                                                   ,(cadr var))))))))
1218                    (aux `(,var))))))
1219       (let ((bindings (mapcan #'process-var lambda-list)))
1220         `(let* ((,args-tail ,args)
1221                 ,@bindings
1222                 (.dummy0.
1223                  ,@(when (eq state 'optional)
1224                      `((unless (null ,args-tail)
1225                          (error 'simple-program-error
1226                                 :format-control "surplus arguments: ~S"
1227                                 :format-arguments (list ,args-tail)))))))
1228            (declare (ignorable ,args-tail .dummy0.))
1229            ,@body)))))
1230
1231 (defun get-key-arg-tail (keyword list)
1232   (loop for (key . tail) on list by #'cddr
1233         when (null tail) do
1234           ;; FIXME: Do we want to export this symbol? Or maybe use an
1235           ;; (ERROR 'SIMPLE-PROGRAM-ERROR) form?
1236           (sb-c::%odd-key-args-error)
1237         when (eq key keyword)
1238           return tail))
1239
1240 (defun walk-method-lambda (method-lambda required-parameters env slots calls)
1241   (let ((call-next-method-p nil)   ; flag indicating that CALL-NEXT-METHOD
1242                                    ; should be in the method definition
1243         (closurep nil)             ; flag indicating that #'CALL-NEXT-METHOD
1244                                    ; was seen in the body of a method
1245         (next-method-p-p nil)      ; flag indicating that NEXT-METHOD-P
1246                                    ; should be in the method definition
1247         (setq-p nil))
1248     (flet ((walk-function (form context env)
1249              (cond ((not (eq context :eval)) form)
1250                    ;; FIXME: Jumping to a conclusion from the way it's used
1251                    ;; above, perhaps CONTEXT should be called SITUATION
1252                    ;; (after the term used in the ANSI specification of
1253                    ;; EVAL-WHEN) and given modern ANSI keyword values
1254                    ;; like :LOAD-TOPLEVEL.
1255                    ((not (listp form)) form)
1256                    ((eq (car form) 'call-next-method)
1257                     (setq call-next-method-p t)
1258                     form)
1259                    ((eq (car form) 'next-method-p)
1260                     (setq next-method-p-p t)
1261                     form)
1262                    ((eq (car form) 'setq)
1263                     ;; FIXME: this is possibly a little strong as
1264                     ;; conditions go.  Ideally we would want to detect
1265                     ;; which, if any, of the method parameters are
1266                     ;; being set, and communicate that information to
1267                     ;; e.g. SPLIT-DECLARATIONS.  However, the brute
1268                     ;; force method doesn't really cost much; a little
1269                     ;; loss of discrimination over IGNORED variables
1270                     ;; should be all.  -- CSR, 2004-07-01
1271                     (setq setq-p t)
1272                     form)
1273                    ((and (eq (car form) 'function)
1274                          (cond ((eq (cadr form) 'call-next-method)
1275                                 (setq call-next-method-p t)
1276                                 (setq closurep t)
1277                                 form)
1278                                ((eq (cadr form) 'next-method-p)
1279                                 (setq next-method-p-p t)
1280                                 (setq closurep t)
1281                                 form)
1282                                (t nil))))
1283                    ((and (memq (car form)
1284                                '(slot-value set-slot-value slot-boundp))
1285                          (constantp (caddr form)))
1286                      (let ((parameter (can-optimize-access form
1287                                                            required-parameters
1288                                                            env)))
1289                       (let ((fun (ecase (car form)
1290                                    (slot-value #'optimize-slot-value)
1291                                    (set-slot-value #'optimize-set-slot-value)
1292                                    (slot-boundp #'optimize-slot-boundp))))
1293                         (funcall fun slots parameter form))))
1294                    ((and (eq (car form) 'apply)
1295                          (consp (cadr form))
1296                          (eq (car (cadr form)) 'function)
1297                          (generic-function-name-p (cadr (cadr form))))
1298                     (optimize-generic-function-call
1299                      form required-parameters env slots calls))
1300                    ((generic-function-name-p (car form))
1301                     (optimize-generic-function-call
1302                      form required-parameters env slots calls))
1303                    (t form))))
1304
1305       (let ((walked-lambda (walk-form method-lambda env #'walk-function)))
1306         (values walked-lambda
1307                 call-next-method-p
1308                 closurep
1309                 next-method-p-p
1310                 setq-p)))))
1311
1312 (defun generic-function-name-p (name)
1313   (and (legal-fun-name-p name)
1314        (gboundp name)
1315        (if (eq *boot-state* 'complete)
1316            (standard-generic-function-p (gdefinition name))
1317            (funcallable-instance-p (gdefinition name)))))
1318 \f
1319 (defvar *method-function-plist* (make-hash-table :test 'eq))
1320 (defvar *mf1* nil)
1321 (defvar *mf1p* nil)
1322 (defvar *mf1cp* nil)
1323 (defvar *mf2* nil)
1324 (defvar *mf2p* nil)
1325 (defvar *mf2cp* nil)
1326
1327 (defun method-function-plist (method-function)
1328   (unless (eq method-function *mf1*)
1329     (rotatef *mf1* *mf2*)
1330     (rotatef *mf1p* *mf2p*)
1331     (rotatef *mf1cp* *mf2cp*))
1332   (unless (or (eq method-function *mf1*) (null *mf1cp*))
1333     (setf (gethash *mf1* *method-function-plist*) *mf1p*))
1334   (unless (eq method-function *mf1*)
1335     (setf *mf1* method-function
1336           *mf1cp* nil
1337           *mf1p* (gethash method-function *method-function-plist*)))
1338   *mf1p*)
1339
1340 (defun (setf method-function-plist)
1341     (val method-function)
1342   (unless (eq method-function *mf1*)
1343     (rotatef *mf1* *mf2*)
1344     (rotatef *mf1cp* *mf2cp*)
1345     (rotatef *mf1p* *mf2p*))
1346   (unless (or (eq method-function *mf1*) (null *mf1cp*))
1347     (setf (gethash *mf1* *method-function-plist*) *mf1p*))
1348   (setf *mf1* method-function
1349         *mf1cp* t
1350         *mf1p* val))
1351
1352 (defun method-function-get (method-function key &optional default)
1353   (getf (method-function-plist method-function) key default))
1354
1355 (defun (setf method-function-get)
1356     (val method-function key)
1357   (setf (getf (method-function-plist method-function) key) val))
1358
1359 (defun method-function-pv-table (method-function)
1360   (method-function-get method-function :pv-table))
1361
1362 (defun method-function-method (method-function)
1363   (method-function-get method-function :method))
1364
1365 (defun method-function-needs-next-methods-p (method-function)
1366   (method-function-get method-function :needs-next-methods-p t))
1367 \f
1368 (defmacro method-function-closure-generator (method-function)
1369   `(method-function-get ,method-function 'closure-generator))
1370
1371 (defun load-defmethod
1372     (class name quals specls ll initargs &optional pv-table-symbol)
1373   (setq initargs (copy-tree initargs))
1374   (let ((method-spec (or (getf initargs :method-spec)
1375                          (make-method-spec name quals specls))))
1376     (setf (getf initargs :method-spec) method-spec)
1377     (load-defmethod-internal class name quals specls
1378                              ll initargs pv-table-symbol)))
1379
1380 (defun load-defmethod-internal
1381     (method-class gf-spec qualifiers specializers lambda-list
1382                   initargs pv-table-symbol)
1383   (when pv-table-symbol
1384     (setf (getf (getf initargs :plist) :pv-table-symbol)
1385           pv-table-symbol))
1386   (when (and (eq *boot-state* 'complete)
1387              (fboundp gf-spec))
1388     (let* ((gf (fdefinition gf-spec))
1389            (method (and (generic-function-p gf)
1390                         (generic-function-methods gf)
1391                         (find-method gf
1392                                      qualifiers
1393                                      (parse-specializers specializers)
1394                                      nil))))
1395       (when method
1396         (style-warn "redefining ~S~{ ~S~} ~S in DEFMETHOD"
1397                     gf-spec qualifiers specializers))))
1398   (let ((method (apply #'add-named-method
1399                        gf-spec qualifiers specializers lambda-list
1400                        :definition-source `((defmethod ,gf-spec
1401                                                 ,@qualifiers
1402                                               ,specializers)
1403                                             ,*load-pathname*)
1404                        initargs)))
1405     (unless (or (eq method-class 'standard-method)
1406                 (eq (find-class method-class nil) (class-of method)))
1407       ;; FIXME: should be STYLE-WARNING?
1408       (format *error-output*
1409               "~&At the time the method with qualifiers ~:S and~%~
1410                specializers ~:S on the generic function ~S~%~
1411                was compiled, the method-class for that generic function was~%~
1412                ~S. But, the method class is now ~S, this~%~
1413                may mean that this method was compiled improperly.~%"
1414               qualifiers specializers gf-spec
1415               method-class (class-name (class-of method))))
1416     method))
1417
1418 (defun make-method-spec (gf-spec qualifiers unparsed-specializers)
1419   `(slow-method ,gf-spec ,@qualifiers ,unparsed-specializers))
1420
1421 (defun initialize-method-function (initargs &optional return-function-p method)
1422   (let* ((mf (getf initargs :function))
1423          (method-spec (getf initargs :method-spec))
1424          (plist (getf initargs :plist))
1425          (pv-table-symbol (getf plist :pv-table-symbol))
1426          (pv-table nil)
1427          (mff (getf initargs :fast-function)))
1428     (flet ((set-mf-property (p v)
1429              (when mf
1430                (setf (method-function-get mf p) v))
1431              (when mff
1432                (setf (method-function-get mff p) v))))
1433       (when method-spec
1434         (when mf
1435           (setq mf (set-fun-name mf method-spec)))
1436         (when mff
1437           (let ((name `(fast-method ,@(cdr method-spec))))
1438             (set-fun-name mff name)
1439             (unless mf
1440               (set-mf-property :name name)))))
1441       (when plist
1442         (let ((snl (getf plist :slot-name-lists))
1443               (cl (getf plist :call-list)))
1444           (when (or snl cl)
1445             (setq pv-table (intern-pv-table :slot-name-lists snl
1446                                             :call-list cl))
1447             (when pv-table (set pv-table-symbol pv-table))
1448             (set-mf-property :pv-table pv-table)))
1449         (loop (when (null plist) (return nil))
1450               (set-mf-property (pop plist) (pop plist)))
1451         (when method
1452           (set-mf-property :method method))
1453         (when return-function-p
1454           (or mf (method-function-from-fast-function mff)))))))
1455 \f
1456 (defun analyze-lambda-list (lambda-list)
1457   (flet (;; FIXME: Is this redundant with SB-C::MAKE-KEYWORD-FOR-ARG?
1458          (parse-key-arg (arg)
1459            (if (listp arg)
1460                (if (listp (car arg))
1461                    (caar arg)
1462                    (keywordicate (car arg)))
1463                (keywordicate arg))))
1464     (let ((nrequired 0)
1465           (noptional 0)
1466           (keysp nil)
1467           (restp nil)
1468           (nrest 0)
1469           (allow-other-keys-p nil)
1470           (keywords ())
1471           (keyword-parameters ())
1472           (state 'required))
1473       (dolist (x lambda-list)
1474         (if (memq x lambda-list-keywords)
1475             (case x
1476               (&optional         (setq state 'optional))
1477               (&key              (setq keysp t
1478                                        state 'key))
1479               (&allow-other-keys (setq allow-other-keys-p t))
1480               (&rest             (setq restp t
1481                                        state 'rest))
1482               (&aux           (return t))
1483               (otherwise
1484                 (error "encountered the non-standard lambda list keyword ~S"
1485                        x)))
1486             (ecase state
1487               (required  (incf nrequired))
1488               (optional  (incf noptional))
1489               (key       (push (parse-key-arg x) keywords)
1490                          (push x keyword-parameters))
1491               (rest      (incf nrest)))))
1492       (when (and restp (zerop nrest))
1493         (error "Error in lambda-list:~%~
1494                 After &REST, a DEFGENERIC lambda-list ~
1495                 must be followed by at least one variable."))
1496       (values nrequired noptional keysp restp allow-other-keys-p
1497               (reverse keywords)
1498               (reverse keyword-parameters)))))
1499
1500 (defun keyword-spec-name (x)
1501   (let ((key (if (atom x) x (car x))))
1502     (if (atom key)
1503         (keywordicate key)
1504         (car key))))
1505
1506 (defun ftype-declaration-from-lambda-list (lambda-list name)
1507   (multiple-value-bind (nrequired noptional keysp restp allow-other-keys-p
1508                                   keywords keyword-parameters)
1509       (analyze-lambda-list lambda-list)
1510     (declare (ignore keyword-parameters))
1511     (let* ((old (info :function :type name)) ;FIXME:FDOCUMENTATION instead?
1512            (old-ftype (if (fun-type-p old) old nil))
1513            (old-restp (and old-ftype (fun-type-rest old-ftype)))
1514            (old-keys (and old-ftype
1515                           (mapcar #'key-info-name
1516                                   (fun-type-keywords
1517                                    old-ftype))))
1518            (old-keysp (and old-ftype (fun-type-keyp old-ftype)))
1519            (old-allowp (and old-ftype
1520                             (fun-type-allowp old-ftype)))
1521            (keywords (union old-keys (mapcar #'keyword-spec-name keywords))))
1522       `(function ,(append (make-list nrequired :initial-element t)
1523                           (when (plusp noptional)
1524                             (append '(&optional)
1525                                     (make-list noptional :initial-element t)))
1526                           (when (or restp old-restp)
1527                             '(&rest t))
1528                           (when (or keysp old-keysp)
1529                             (append '(&key)
1530                                     (mapcar (lambda (key)
1531                                               `(,key t))
1532                                             keywords)
1533                                     (when (or allow-other-keys-p old-allowp)
1534                                       '(&allow-other-keys)))))
1535                  *))))
1536
1537 (defun defgeneric-declaration (spec lambda-list)
1538   `(ftype ,(ftype-declaration-from-lambda-list lambda-list spec) ,spec))
1539 \f
1540 ;;;; early generic function support
1541
1542 (defvar *!early-generic-functions* ())
1543
1544 (defun ensure-generic-function (fun-name
1545                                 &rest all-keys
1546                                 &key environment
1547                                 &allow-other-keys)
1548   (declare (ignore environment))
1549   (let ((existing (and (gboundp fun-name)
1550                        (gdefinition fun-name))))
1551     (if (and existing
1552              (eq *boot-state* 'complete)
1553              (null (generic-function-p existing)))
1554         (generic-clobbers-function fun-name)
1555         (apply #'ensure-generic-function-using-class
1556                existing fun-name all-keys))))
1557
1558 (defun generic-clobbers-function (fun-name)
1559   (error 'simple-program-error
1560          :format-control "~S already names an ordinary function or a macro."
1561          :format-arguments (list fun-name)))
1562
1563 (defvar *sgf-wrapper*
1564   (boot-make-wrapper (early-class-size 'standard-generic-function)
1565                      'standard-generic-function))
1566
1567 (defvar *sgf-slots-init*
1568   (mapcar (lambda (canonical-slot)
1569             (if (memq (getf canonical-slot :name) '(arg-info source))
1570                 +slot-unbound+
1571                 (let ((initfunction (getf canonical-slot :initfunction)))
1572                   (if initfunction
1573                       (funcall initfunction)
1574                       +slot-unbound+))))
1575           (early-collect-inheritance 'standard-generic-function)))
1576
1577 (defvar *sgf-method-class-index*
1578   (!bootstrap-slot-index 'standard-generic-function 'method-class))
1579
1580 (defun early-gf-p (x)
1581   (and (fsc-instance-p x)
1582        (eq (clos-slots-ref (get-slots x) *sgf-method-class-index*)
1583            +slot-unbound+)))
1584
1585 (defvar *sgf-methods-index*
1586   (!bootstrap-slot-index 'standard-generic-function 'methods))
1587
1588 (defmacro early-gf-methods (gf)
1589   `(clos-slots-ref (get-slots ,gf) *sgf-methods-index*))
1590
1591 (defvar *sgf-arg-info-index*
1592   (!bootstrap-slot-index 'standard-generic-function 'arg-info))
1593
1594 (defmacro early-gf-arg-info (gf)
1595   `(clos-slots-ref (get-slots ,gf) *sgf-arg-info-index*))
1596
1597 (defvar *sgf-dfun-state-index*
1598   (!bootstrap-slot-index 'standard-generic-function 'dfun-state))
1599
1600 (defstruct (arg-info
1601             (:conc-name nil)
1602             (:constructor make-arg-info ())
1603             (:copier nil))
1604   (arg-info-lambda-list :no-lambda-list)
1605   arg-info-precedence
1606   arg-info-metatypes
1607   arg-info-number-optional
1608   arg-info-key/rest-p
1609   arg-info-keys   ;nil        no &KEY or &REST allowed
1610                   ;(k1 k2 ..) Each method must accept these &KEY arguments.
1611                   ;T          must have &KEY or &REST
1612
1613   gf-info-simple-accessor-type ; nil, reader, writer, boundp
1614   (gf-precompute-dfun-and-emf-p nil) ; set by set-arg-info
1615
1616   gf-info-static-c-a-m-emf
1617   (gf-info-c-a-m-emf-std-p t)
1618   gf-info-fast-mf-p)
1619
1620 #-sb-fluid (declaim (sb-ext:freeze-type arg-info))
1621
1622 (defun arg-info-valid-p (arg-info)
1623   (not (null (arg-info-number-optional arg-info))))
1624
1625 (defun arg-info-applyp (arg-info)
1626   (or (plusp (arg-info-number-optional arg-info))
1627       (arg-info-key/rest-p arg-info)))
1628
1629 (defun arg-info-number-required (arg-info)
1630   (length (arg-info-metatypes arg-info)))
1631
1632 (defun arg-info-nkeys (arg-info)
1633   (count-if (lambda (x) (neq x t)) (arg-info-metatypes arg-info)))
1634
1635 ;;; Keep pages clean by not setting if the value is already the same.
1636 (defmacro esetf (pos val)
1637   (with-unique-names (valsym)
1638     `(let ((,valsym ,val))
1639        (unless (equal ,pos ,valsym)
1640          (setf ,pos ,valsym)))))
1641
1642 (defun create-gf-lambda-list (lambda-list)
1643   ;;; Create a gf lambda list from a method lambda list
1644   (loop for x in lambda-list
1645         collect (if (consp x) (list (car x)) x)
1646         if (eq x '&key) do (loop-finish)))
1647
1648 (defun set-arg-info (gf &key new-method (lambda-list nil lambda-list-p)
1649                         argument-precedence-order)
1650   (let* ((arg-info (if (eq *boot-state* 'complete)
1651                        (gf-arg-info gf)
1652                        (early-gf-arg-info gf)))
1653          (methods (if (eq *boot-state* 'complete)
1654                       (generic-function-methods gf)
1655                       (early-gf-methods gf)))
1656          (was-valid-p (integerp (arg-info-number-optional arg-info)))
1657          (first-p (and new-method (null (cdr methods)))))
1658     (when (and (not lambda-list-p) methods)
1659       (setq lambda-list (gf-lambda-list gf)))
1660     (when (or lambda-list-p
1661               (and first-p
1662                    (eq (arg-info-lambda-list arg-info) :no-lambda-list)))
1663       (multiple-value-bind (nreq nopt keysp restp allow-other-keys-p keywords)
1664           (analyze-lambda-list lambda-list)
1665         (when (and methods (not first-p))
1666           (let ((gf-nreq (arg-info-number-required arg-info))
1667                 (gf-nopt (arg-info-number-optional arg-info))
1668                 (gf-key/rest-p (arg-info-key/rest-p arg-info)))
1669             (unless (and (= nreq gf-nreq)
1670                          (= nopt gf-nopt)
1671                          (eq (or keysp restp) gf-key/rest-p))
1672               (error "The lambda-list ~S is incompatible with ~
1673                      existing methods of ~S."
1674                      lambda-list gf))))
1675         (esetf (arg-info-lambda-list arg-info)
1676                (if lambda-list-p
1677                    lambda-list
1678                    (create-gf-lambda-list lambda-list)))
1679         (when (or lambda-list-p argument-precedence-order
1680                   (null (arg-info-precedence arg-info)))
1681           (esetf (arg-info-precedence arg-info)
1682                  (compute-precedence lambda-list nreq
1683                                      argument-precedence-order)))
1684         (esetf (arg-info-metatypes arg-info) (make-list nreq))
1685         (esetf (arg-info-number-optional arg-info) nopt)
1686         (esetf (arg-info-key/rest-p arg-info) (not (null (or keysp restp))))
1687         (esetf (arg-info-keys arg-info)
1688                (if lambda-list-p
1689                    (if allow-other-keys-p t keywords)
1690                    (arg-info-key/rest-p arg-info)))))
1691     (when new-method
1692       (check-method-arg-info gf arg-info new-method))
1693     (set-arg-info1 gf arg-info new-method methods was-valid-p first-p)
1694     arg-info))
1695
1696 (defun check-method-arg-info (gf arg-info method)
1697   (multiple-value-bind (nreq nopt keysp restp allow-other-keys-p keywords)
1698       (analyze-lambda-list (if (consp method)
1699                                (early-method-lambda-list method)
1700                                (method-lambda-list method)))
1701     (flet ((lose (string &rest args)
1702              (error 'simple-program-error
1703                     :format-control "~@<attempt to add the method~2I~_~S~I~_~
1704                                      to the generic function~2I~_~S;~I~_~
1705                                      but ~?~:>"
1706                     :format-arguments (list method gf string args)))
1707            (comparison-description (x y)
1708              (if (> x y) "more" "fewer")))
1709       (let ((gf-nreq (arg-info-number-required arg-info))
1710             (gf-nopt (arg-info-number-optional arg-info))
1711             (gf-key/rest-p (arg-info-key/rest-p arg-info))
1712             (gf-keywords (arg-info-keys arg-info)))
1713         (unless (= nreq gf-nreq)
1714           (lose
1715            "the method has ~A required arguments than the generic function."
1716            (comparison-description nreq gf-nreq)))
1717         (unless (= nopt gf-nopt)
1718           (lose
1719            "the method has ~A optional arguments than the generic function."
1720            (comparison-description nopt gf-nopt)))
1721         (unless (eq (or keysp restp) gf-key/rest-p)
1722           (lose
1723            "the method and generic function differ in whether they accept~_~
1724             &REST or &KEY arguments."))
1725         (when (consp gf-keywords)
1726           (unless (or (and restp (not keysp))
1727                       allow-other-keys-p
1728                       (every (lambda (k) (memq k keywords)) gf-keywords))
1729             (lose "the method does not accept each of the &KEY arguments~2I~_~
1730                    ~S."
1731                   gf-keywords)))))))
1732
1733 (defun set-arg-info1 (gf arg-info new-method methods was-valid-p first-p)
1734   (let* ((existing-p (and methods (cdr methods) new-method))
1735          (nreq (length (arg-info-metatypes arg-info)))
1736          (metatypes (if existing-p
1737                         (arg-info-metatypes arg-info)
1738                         (make-list nreq)))
1739          (type (if existing-p
1740                    (gf-info-simple-accessor-type arg-info)
1741                    nil)))
1742     (when (arg-info-valid-p arg-info)
1743       (dolist (method (if new-method (list new-method) methods))
1744         (let* ((specializers (if (or (eq *boot-state* 'complete)
1745                                      (not (consp method)))
1746                                  (method-specializers method)
1747                                  (early-method-specializers method t)))
1748                (class (if (or (eq *boot-state* 'complete) (not (consp method)))
1749                           (class-of method)
1750                           (early-method-class method)))
1751                (new-type (when (and class
1752                                     (or (not (eq *boot-state* 'complete))
1753                                         (eq (generic-function-method-combination gf)
1754                                             *standard-method-combination*)))
1755                            (cond ((eq class *the-class-standard-reader-method*)
1756                                   'reader)
1757                                  ((eq class *the-class-standard-writer-method*)
1758                                   'writer)
1759                                  ((eq class *the-class-standard-boundp-method*)
1760                                   'boundp)))))
1761           (setq metatypes (mapcar #'raise-metatype metatypes specializers))
1762           (setq type (cond ((null type) new-type)
1763                            ((eq type new-type) type)
1764                            (t nil)))))
1765       (esetf (arg-info-metatypes arg-info) metatypes)
1766       (esetf (gf-info-simple-accessor-type arg-info) type)))
1767   (when (or (not was-valid-p) first-p)
1768     (multiple-value-bind (c-a-m-emf std-p)
1769         (if (early-gf-p gf)
1770             (values t t)
1771             (compute-applicable-methods-emf gf))
1772       (esetf (gf-info-static-c-a-m-emf arg-info) c-a-m-emf)
1773       (esetf (gf-info-c-a-m-emf-std-p arg-info) std-p)
1774       (unless (gf-info-c-a-m-emf-std-p arg-info)
1775         (esetf (gf-info-simple-accessor-type arg-info) t))))
1776   (unless was-valid-p
1777     (let ((name (if (eq *boot-state* 'complete)
1778                     (generic-function-name gf)
1779                     (!early-gf-name gf))))
1780       (esetf (gf-precompute-dfun-and-emf-p arg-info)
1781              (cond
1782                ((and (consp name)
1783                      (member (car name)
1784                              *internal-pcl-generalized-fun-name-symbols*))
1785                 nil)
1786                (t (let* ((symbol (fun-name-block-name name))
1787                          (package (symbol-package symbol)))
1788                     (and (or (eq package *pcl-package*)
1789                              (memq package (package-use-list *pcl-package*)))
1790                          ;; FIXME: this test will eventually be
1791                          ;; superseded by the *internal-pcl...* test,
1792                          ;; above.  While we are in a process of
1793                          ;; transition, however, it should probably
1794                          ;; remain.
1795                          (not (find #\Space (symbol-name symbol))))))))))
1796   (esetf (gf-info-fast-mf-p arg-info)
1797          (or (not (eq *boot-state* 'complete))
1798              (let* ((method-class (generic-function-method-class gf))
1799                     (methods (compute-applicable-methods
1800                               #'make-method-lambda
1801                               (list gf (class-prototype method-class)
1802                                     '(lambda) nil))))
1803                (and methods (null (cdr methods))
1804                     (let ((specls (method-specializers (car methods))))
1805                       (and (classp (car specls))
1806                            (eq 'standard-generic-function
1807                                (class-name (car specls)))
1808                            (classp (cadr specls))
1809                            (eq 'standard-method
1810                                (class-name (cadr specls)))))))))
1811   arg-info)
1812
1813 ;;; This is the early definition of ENSURE-GENERIC-FUNCTION-USING-CLASS.
1814 ;;;
1815 ;;; The STATIC-SLOTS field of the funcallable instances used as early
1816 ;;; generic functions is used to store the early methods and early
1817 ;;; discriminator code for the early generic function. The static
1818 ;;; slots field of the fins contains a list whose:
1819 ;;;    CAR    -   a list of the early methods on this early gf
1820 ;;;    CADR   -   the early discriminator code for this method
1821 (defun ensure-generic-function-using-class (existing spec &rest keys
1822                                             &key (lambda-list nil
1823                                                               lambda-list-p)
1824                                             argument-precedence-order
1825                                             &allow-other-keys)
1826   (declare (ignore keys))
1827   (cond ((and existing (early-gf-p existing))
1828          (when lambda-list-p
1829            (set-arg-info existing :lambda-list lambda-list))
1830          existing)
1831         ((assoc spec *!generic-function-fixups* :test #'equal)
1832          (if existing
1833              (make-early-gf spec lambda-list lambda-list-p existing
1834                             argument-precedence-order)
1835              (error "The function ~S is not already defined." spec)))
1836         (existing
1837          (error "~S should be on the list ~S."
1838                 spec
1839                 '*!generic-function-fixups*))
1840         (t
1841          (pushnew spec *!early-generic-functions* :test #'equal)
1842          (make-early-gf spec lambda-list lambda-list-p nil
1843                         argument-precedence-order))))
1844
1845 (defun make-early-gf (spec &optional lambda-list lambda-list-p
1846                       function argument-precedence-order)
1847   (let ((fin (allocate-funcallable-instance *sgf-wrapper* *sgf-slots-init*)))
1848     (set-funcallable-instance-function
1849      fin
1850      (or function
1851          (if (eq spec 'print-object)
1852              #'(instance-lambda (instance stream)
1853                  (print-unreadable-object (instance stream :identity t)
1854                    (format stream "std-instance")))
1855              #'(instance-lambda (&rest args)
1856                  (declare (ignore args))
1857                  (error "The function of the funcallable-instance ~S~
1858                          has not been set." fin)))))
1859     (setf (gdefinition spec) fin)
1860     (!bootstrap-set-slot 'standard-generic-function fin 'name spec)
1861     (!bootstrap-set-slot 'standard-generic-function
1862                          fin
1863                          'source
1864                          *load-pathname*)
1865     (set-fun-name fin spec)
1866     (let ((arg-info (make-arg-info)))
1867       (setf (early-gf-arg-info fin) arg-info)
1868       (when lambda-list-p
1869         (proclaim (defgeneric-declaration spec lambda-list))
1870         (if argument-precedence-order
1871             (set-arg-info fin
1872                           :lambda-list lambda-list
1873                           :argument-precedence-order argument-precedence-order)
1874             (set-arg-info fin :lambda-list lambda-list))))
1875     fin))
1876
1877 (defun set-dfun (gf &optional dfun cache info)
1878   (when cache
1879     (setf (cache-owner cache) gf))
1880   (let ((new-state (if (and dfun (or cache info))
1881                        (list* dfun cache info)
1882                        dfun)))
1883     (if (eq *boot-state* 'complete)
1884         (setf (gf-dfun-state gf) new-state)
1885         (setf (clos-slots-ref (get-slots gf) *sgf-dfun-state-index*)
1886               new-state)))
1887   dfun)
1888
1889 (defun gf-dfun-cache (gf)
1890   (let ((state (if (eq *boot-state* 'complete)
1891                    (gf-dfun-state gf)
1892                    (clos-slots-ref (get-slots gf) *sgf-dfun-state-index*))))
1893     (typecase state
1894       (function nil)
1895       (cons (cadr state)))))
1896
1897 (defun gf-dfun-info (gf)
1898   (let ((state (if (eq *boot-state* 'complete)
1899                    (gf-dfun-state gf)
1900                    (clos-slots-ref (get-slots gf) *sgf-dfun-state-index*))))
1901     (typecase state
1902       (function nil)
1903       (cons (cddr state)))))
1904
1905 (defvar *sgf-name-index*
1906   (!bootstrap-slot-index 'standard-generic-function 'name))
1907
1908 (defun !early-gf-name (gf)
1909   (clos-slots-ref (get-slots gf) *sgf-name-index*))
1910
1911 (defun gf-lambda-list (gf)
1912   (let ((arg-info (if (eq *boot-state* 'complete)
1913                       (gf-arg-info gf)
1914                       (early-gf-arg-info gf))))
1915     (if (eq :no-lambda-list (arg-info-lambda-list arg-info))
1916         (let ((methods (if (eq *boot-state* 'complete)
1917                            (generic-function-methods gf)
1918                            (early-gf-methods gf))))
1919           (if (null methods)
1920               (progn
1921                 (warn "no way to determine the lambda list for ~S" gf)
1922                 nil)
1923               (let* ((method (car (last methods)))
1924                      (ll (if (consp method)
1925                              (early-method-lambda-list method)
1926                              (method-lambda-list method))))
1927                 (create-gf-lambda-list ll))))
1928         (arg-info-lambda-list arg-info))))
1929
1930 (defmacro real-ensure-gf-internal (gf-class all-keys env)
1931   `(progn
1932      (cond ((symbolp ,gf-class)
1933             (setq ,gf-class (find-class ,gf-class t ,env)))
1934            ((classp ,gf-class))
1935            (t
1936             (error "The :GENERIC-FUNCTION-CLASS argument (~S) was neither a~%~
1937                     class nor a symbol that names a class."
1938                    ,gf-class)))
1939      (remf ,all-keys :generic-function-class)
1940      (remf ,all-keys :environment)
1941      (let ((combin (getf ,all-keys :method-combination '.shes-not-there.)))
1942        (unless (eq combin '.shes-not-there.)
1943          (setf (getf ,all-keys :method-combination)
1944                (find-method-combination (class-prototype ,gf-class)
1945                                         (car combin)
1946                                         (cdr combin)))))
1947     (let ((method-class (getf ,all-keys :method-class '.shes-not-there.)))
1948       (unless (eq method-class '.shes-not-there.)
1949         (setf (getf ,all-keys :method-class)
1950               (find-class method-class t ,env))))))
1951
1952 (defun real-ensure-gf-using-class--generic-function
1953        (existing
1954         fun-name
1955         &rest all-keys
1956         &key environment (lambda-list nil lambda-list-p)
1957              (generic-function-class 'standard-generic-function gf-class-p)
1958         &allow-other-keys)
1959   (real-ensure-gf-internal generic-function-class all-keys environment)
1960   (unless (or (null gf-class-p)
1961               (eq (class-of existing) generic-function-class))
1962     (change-class existing generic-function-class))
1963   (prog1
1964       (apply #'reinitialize-instance existing all-keys)
1965     (when lambda-list-p
1966       (proclaim (defgeneric-declaration fun-name lambda-list)))))
1967
1968 (defun real-ensure-gf-using-class--null
1969        (existing
1970         fun-name
1971         &rest all-keys
1972         &key environment (lambda-list nil lambda-list-p)
1973              (generic-function-class 'standard-generic-function)
1974         &allow-other-keys)
1975   (declare (ignore existing))
1976   (real-ensure-gf-internal generic-function-class all-keys environment)
1977   (prog1
1978       (setf (gdefinition fun-name)
1979             (apply #'make-instance generic-function-class
1980                    :name fun-name all-keys))
1981     (when lambda-list-p
1982       (proclaim (defgeneric-declaration fun-name lambda-list)))))
1983 \f
1984 (defun get-generic-fun-info (gf)
1985   ;; values   nreq applyp metatypes nkeys arg-info
1986   (multiple-value-bind (applyp metatypes arg-info)
1987       (let* ((arg-info (if (early-gf-p gf)
1988                            (early-gf-arg-info gf)
1989                            (gf-arg-info gf)))
1990              (metatypes (arg-info-metatypes arg-info)))
1991         (values (arg-info-applyp arg-info)
1992                 metatypes
1993                 arg-info))
1994     (values (length metatypes) applyp metatypes
1995             (count-if (lambda (x) (neq x t)) metatypes)
1996             arg-info)))
1997
1998 (defun early-make-a-method (class qualifiers arglist specializers initargs doc
1999                             &optional slot-name)
2000   (initialize-method-function initargs)
2001   (let ((parsed ())
2002         (unparsed ()))
2003     ;; Figure out whether we got class objects or class names as the
2004     ;; specializers and set parsed and unparsed appropriately. If we
2005     ;; got class objects, then we can compute unparsed, but if we got
2006     ;; class names we don't try to compute parsed.
2007     ;;
2008     ;; Note that the use of not symbolp in this call to every should be
2009     ;; read as 'classp' we can't use classp itself because it doesn't
2010     ;; exist yet.
2011     (if (every (lambda (s) (not (symbolp s))) specializers)
2012         (setq parsed specializers
2013               unparsed (mapcar (lambda (s)
2014                                  (if (eq s t) t (class-name s)))
2015                                specializers))
2016         (setq unparsed specializers
2017               parsed ()))
2018     (list :early-method           ;This is an early method dammit!
2019
2020           (getf initargs :function)
2021           (getf initargs :fast-function)
2022
2023           parsed                  ;The parsed specializers. This is used
2024                                   ;by early-method-specializers to cache
2025                                   ;the parse. Note that this only comes
2026                                   ;into play when there is more than one
2027                                   ;early method on an early gf.
2028
2029           (list class        ;A list to which real-make-a-method
2030                 qualifiers      ;can be applied to make a real method
2031                 arglist    ;corresponding to this early one.
2032                 unparsed
2033                 initargs
2034                 doc
2035                 slot-name))))
2036
2037 (defun real-make-a-method
2038        (class qualifiers lambda-list specializers initargs doc
2039         &optional slot-name)
2040   (setq specializers (parse-specializers specializers))
2041   (apply #'make-instance class
2042          :qualifiers qualifiers
2043          :lambda-list lambda-list
2044          :specializers specializers
2045          :documentation doc
2046          :slot-name slot-name
2047          :allow-other-keys t
2048          initargs))
2049
2050 (defun early-method-function (early-method)
2051   (values (cadr early-method) (caddr early-method)))
2052
2053 (defun early-method-class (early-method)
2054   (find-class (car (fifth early-method))))
2055
2056 (defun early-method-standard-accessor-p (early-method)
2057   (let ((class (first (fifth early-method))))
2058     (or (eq class 'standard-reader-method)
2059         (eq class 'standard-writer-method)
2060         (eq class 'standard-boundp-method))))
2061
2062 (defun early-method-standard-accessor-slot-name (early-method)
2063   (seventh (fifth early-method)))
2064
2065 ;;; Fetch the specializers of an early method. This is basically just
2066 ;;; a simple accessor except that when the second argument is t, this
2067 ;;; converts the specializers from symbols into class objects. The
2068 ;;; class objects are cached in the early method, this makes
2069 ;;; bootstrapping faster because the class objects only have to be
2070 ;;; computed once.
2071 ;;;
2072 ;;; NOTE:
2073 ;;;  The second argument should only be passed as T by
2074 ;;;  early-lookup-method. This is to implement the rule that only when
2075 ;;;  there is more than one early method on a generic function is the
2076 ;;;  conversion from class names to class objects done. This
2077 ;;;  corresponds to the fact that we are only allowed to have one
2078 ;;;  method on any generic function up until the time classes exist.
2079 (defun early-method-specializers (early-method &optional objectsp)
2080   (if (and (listp early-method)
2081            (eq (car early-method) :early-method))
2082       (cond ((eq objectsp t)
2083              (or (fourth early-method)
2084                  (setf (fourth early-method)
2085                        (mapcar #'find-class (cadddr (fifth early-method))))))
2086             (t
2087              (cadddr (fifth early-method))))
2088       (error "~S is not an early-method." early-method)))
2089
2090 (defun early-method-qualifiers (early-method)
2091   (cadr (fifth early-method)))
2092
2093 (defun early-method-lambda-list (early-method)
2094   (caddr (fifth early-method)))
2095
2096 (defun early-add-named-method (generic-function-name
2097                                qualifiers
2098                                specializers
2099                                arglist
2100                                &rest initargs)
2101   (let* ((gf (ensure-generic-function generic-function-name))
2102          (existing
2103            (dolist (m (early-gf-methods gf))
2104              (when (and (equal (early-method-specializers m) specializers)
2105                         (equal (early-method-qualifiers m) qualifiers))
2106                (return m))))
2107          (new (make-a-method 'standard-method
2108                              qualifiers
2109                              arglist
2110                              specializers
2111                              initargs
2112                              ())))
2113     (when existing (remove-method gf existing))
2114     (add-method gf new)))
2115
2116 ;;; This is the early version of ADD-METHOD. Later this will become a
2117 ;;; generic function. See !FIX-EARLY-GENERIC-FUNCTIONS which has
2118 ;;; special knowledge about ADD-METHOD.
2119 (defun add-method (generic-function method)
2120   (when (not (fsc-instance-p generic-function))
2121     (error "Early ADD-METHOD didn't get a funcallable instance."))
2122   (when (not (and (listp method) (eq (car method) :early-method)))
2123     (error "Early ADD-METHOD didn't get an early method."))
2124   (push method (early-gf-methods generic-function))
2125   (set-arg-info generic-function :new-method method)
2126   (unless (assoc (!early-gf-name generic-function)
2127                  *!generic-function-fixups*
2128                  :test #'equal)
2129     (update-dfun generic-function)))
2130
2131 ;;; This is the early version of REMOVE-METHOD. See comments on
2132 ;;; the early version of ADD-METHOD.
2133 (defun remove-method (generic-function method)
2134   (when (not (fsc-instance-p generic-function))
2135     (error "An early remove-method didn't get a funcallable instance."))
2136   (when (not (and (listp method) (eq (car method) :early-method)))
2137     (error "An early remove-method didn't get an early method."))
2138   (setf (early-gf-methods generic-function)
2139         (remove method (early-gf-methods generic-function)))
2140   (set-arg-info generic-function)
2141   (unless (assoc (!early-gf-name generic-function)
2142                  *!generic-function-fixups*
2143                  :test #'equal)
2144     (update-dfun generic-function)))
2145
2146 ;;; This is the early version of GET-METHOD. See comments on the early
2147 ;;; version of ADD-METHOD.
2148 (defun get-method (generic-function qualifiers specializers
2149                                     &optional (errorp t))
2150   (if (early-gf-p generic-function)
2151       (or (dolist (m (early-gf-methods generic-function))
2152             (when (and (or (equal (early-method-specializers m nil)
2153                                   specializers)
2154                            (equal (early-method-specializers m t)
2155                                   specializers))
2156                        (equal (early-method-qualifiers m) qualifiers))
2157               (return m)))
2158           (if errorp
2159               (error "can't get early method")
2160               nil))
2161       (real-get-method generic-function qualifiers specializers errorp)))
2162
2163 (defun !fix-early-generic-functions ()
2164   (let ((accessors nil))
2165     ;; Rearrange *!EARLY-GENERIC-FUNCTIONS* to speed up
2166     ;; FIX-EARLY-GENERIC-FUNCTIONS.
2167     (dolist (early-gf-spec *!early-generic-functions*)
2168       (when (every #'early-method-standard-accessor-p
2169                    (early-gf-methods (gdefinition early-gf-spec)))
2170         (push early-gf-spec accessors)))
2171     (dolist (spec (nconc accessors
2172                          '(accessor-method-slot-name
2173                            generic-function-methods
2174                            method-specializers
2175                            specializerp
2176                            specializer-type
2177                            specializer-class
2178                            slot-definition-location
2179                            slot-definition-name
2180                            class-slots
2181                            gf-arg-info
2182                            class-precedence-list
2183                            slot-boundp-using-class
2184                            (setf slot-value-using-class)
2185                            slot-value-using-class
2186                            structure-class-p
2187                            standard-class-p
2188                            funcallable-standard-class-p
2189                            specializerp)))
2190       (/show spec)
2191       (setq *!early-generic-functions*
2192             (cons spec
2193                   (delete spec *!early-generic-functions* :test #'equal))))
2194
2195     (dolist (early-gf-spec *!early-generic-functions*)
2196       (/show early-gf-spec)
2197       (let* ((gf (gdefinition early-gf-spec))
2198              (methods (mapcar (lambda (early-method)
2199                                 (let ((args (copy-list (fifth
2200                                                         early-method))))
2201                                   (setf (fourth args)
2202                                         (early-method-specializers
2203                                          early-method t))
2204                                   (apply #'real-make-a-method args)))
2205                               (early-gf-methods gf))))
2206         (setf (generic-function-method-class gf) *the-class-standard-method*)
2207         (setf (generic-function-method-combination gf)
2208               *standard-method-combination*)
2209         (set-methods gf methods)))
2210
2211     (dolist (fn *!early-functions*)
2212       (/show fn)
2213       (setf (gdefinition (car fn)) (fdefinition (caddr fn))))
2214
2215     (dolist (fixup *!generic-function-fixups*)
2216       (/show fixup)
2217       (let* ((fspec (car fixup))
2218              (gf (gdefinition fspec))
2219              (methods (mapcar (lambda (method)
2220                                 (let* ((lambda-list (first method))
2221                                        (specializers (second method))
2222                                        (method-fn-name (third method))
2223                                        (fn-name (or method-fn-name fspec))
2224                                        (fn (fdefinition fn-name))
2225                                        (initargs
2226                                         (list :function
2227                                               (set-fun-name
2228                                                (lambda (args next-methods)
2229                                                  (declare (ignore
2230                                                            next-methods))
2231                                                  (apply fn args))
2232                                                `(call ,fn-name)))))
2233                                   (declare (type function fn))
2234                                   (make-a-method 'standard-method
2235                                                  ()
2236                                                  lambda-list
2237                                                  specializers
2238                                                  initargs
2239                                                  nil)))
2240                               (cdr fixup))))
2241         (setf (generic-function-method-class gf) *the-class-standard-method*)
2242         (setf (generic-function-method-combination gf)
2243               *standard-method-combination*)
2244         (set-methods gf methods))))
2245   (/show "leaving !FIX-EARLY-GENERIC-FUNCTIONS"))
2246 \f
2247 ;;; PARSE-DEFMETHOD is used by DEFMETHOD to parse the &REST argument
2248 ;;; into the 'real' arguments. This is where the syntax of DEFMETHOD
2249 ;;; is really implemented.
2250 (defun parse-defmethod (cdr-of-form)
2251   (declare (list cdr-of-form))
2252   (let ((name (pop cdr-of-form))
2253         (qualifiers ())
2254         (spec-ll ()))
2255     (loop (if (and (car cdr-of-form) (atom (car cdr-of-form)))
2256               (push (pop cdr-of-form) qualifiers)
2257               (return (setq qualifiers (nreverse qualifiers)))))
2258     (setq spec-ll (pop cdr-of-form))
2259     (values name qualifiers spec-ll cdr-of-form)))
2260
2261 (defun parse-specializers (specializers)
2262   (declare (list specializers))
2263   (flet ((parse (spec)
2264            (let ((result (specializer-from-type spec)))
2265              (if (specializerp result)
2266                  result
2267                  (if (symbolp spec)
2268                      (error "~S was used as a specializer,~%~
2269                              but is not the name of a class."
2270                             spec)
2271                      (error "~S is not a legal specializer." spec))))))
2272     (mapcar #'parse specializers)))
2273
2274 (defun unparse-specializers (specializers-or-method)
2275   (if (listp specializers-or-method)
2276       (flet ((unparse (spec)
2277                (if (specializerp spec)
2278                    (let ((type (specializer-type spec)))
2279                      (if (and (consp type)
2280                               (eq (car type) 'class))
2281                          (let* ((class (cadr type))
2282                                 (class-name (class-name class)))
2283                            (if (eq class (find-class class-name nil))
2284                                class-name
2285                                type))
2286                          type))
2287                    (error "~S is not a legal specializer." spec))))
2288         (mapcar #'unparse specializers-or-method))
2289       (unparse-specializers (method-specializers specializers-or-method))))
2290
2291 (defun parse-method-or-spec (spec &optional (errorp t))
2292   (let (gf method name temp)
2293     (if (method-p spec)
2294         (setq method spec
2295               gf (method-generic-function method)
2296               temp (and gf (generic-function-name gf))
2297               name (if temp
2298                        (make-method-spec temp
2299                                          (method-qualifiers method)
2300                                          (unparse-specializers
2301                                           (method-specializers method)))
2302                        (make-symbol (format nil "~S" method))))
2303         (multiple-value-bind (gf-spec quals specls)
2304             (parse-defmethod spec)
2305           (and (setq gf (and (or errorp (gboundp gf-spec))
2306                              (gdefinition gf-spec)))
2307                (let ((nreq (compute-discriminating-function-arglist-info gf)))
2308                  (setq specls (append (parse-specializers specls)
2309                                       (make-list (- nreq (length specls))
2310                                                  :initial-element
2311                                                  *the-class-t*)))
2312                  (and
2313                    (setq method (get-method gf quals specls errorp))
2314                    (setq name
2315                          (make-method-spec
2316                           gf-spec quals (unparse-specializers specls))))))))
2317     (values gf method name)))
2318 \f
2319 (defun extract-parameters (specialized-lambda-list)
2320   (multiple-value-bind (parameters ignore1 ignore2)
2321       (parse-specialized-lambda-list specialized-lambda-list)
2322     (declare (ignore ignore1 ignore2))
2323     parameters))
2324
2325 (defun extract-lambda-list (specialized-lambda-list)
2326   (multiple-value-bind (ignore1 lambda-list ignore2)
2327       (parse-specialized-lambda-list specialized-lambda-list)
2328     (declare (ignore ignore1 ignore2))
2329     lambda-list))
2330
2331 (defun extract-specializer-names (specialized-lambda-list)
2332   (multiple-value-bind (ignore1 ignore2 specializers)
2333       (parse-specialized-lambda-list specialized-lambda-list)
2334     (declare (ignore ignore1 ignore2))
2335     specializers))
2336
2337 (defun extract-required-parameters (specialized-lambda-list)
2338   (multiple-value-bind (ignore1 ignore2 ignore3 required-parameters)
2339       (parse-specialized-lambda-list specialized-lambda-list)
2340     (declare (ignore ignore1 ignore2 ignore3))
2341     required-parameters))
2342
2343 (define-condition specialized-lambda-list-error
2344     (reference-condition simple-program-error)
2345   ()
2346   (:default-initargs :references (list '(:ansi-cl :section (3 4 3)))))
2347
2348 (defun parse-specialized-lambda-list
2349     (arglist
2350      &optional supplied-keywords (allowed-keywords '(&optional &rest &key &aux))
2351      &aux (specialized-lambda-list-keywords
2352            '(&optional &rest &key &allow-other-keys &aux)))
2353   (let ((arg (car arglist)))
2354     (cond ((null arglist) (values nil nil nil nil))
2355           ((eq arg '&aux)
2356            (values nil arglist nil nil))
2357           ((memq arg lambda-list-keywords)
2358            ;; non-standard lambda-list-keywords are errors.
2359            (unless (memq arg specialized-lambda-list-keywords)
2360              (error 'specialized-lambda-list-error
2361                     :format-control "unknown specialized-lambda-list ~
2362                                      keyword ~S~%"
2363                     :format-arguments (list arg)))
2364            ;; no multiple &rest x &rest bla specifying
2365            (when (memq arg supplied-keywords)
2366              (error 'specialized-lambda-list-error
2367                     :format-control "multiple occurrence of ~
2368                                      specialized-lambda-list keyword ~S~%"
2369                     :format-arguments (list arg)))
2370            ;; And no placing &key in front of &optional, either.
2371            (unless (memq arg allowed-keywords)
2372              (error 'specialized-lambda-list-error
2373                     :format-control "misplaced specialized-lambda-list ~
2374                                      keyword ~S~%"
2375                     :format-arguments (list arg)))
2376            ;; When we are at a lambda-list keyword, the parameters
2377            ;; don't include the lambda-list keyword; the lambda-list
2378            ;; does include the lambda-list keyword; and no
2379            ;; specializers are allowed to follow the lambda-list
2380            ;; keywords (at least for now).
2381            (multiple-value-bind (parameters lambda-list)
2382                (parse-specialized-lambda-list (cdr arglist)
2383                                               (cons arg supplied-keywords)
2384                                               (if (eq arg '&key)
2385                                                   (cons '&allow-other-keys
2386                                                         (cdr (member arg allowed-keywords)))
2387                                                 (cdr (member arg allowed-keywords))))
2388              (when (and (eq arg '&rest)
2389                         (or (null lambda-list)
2390                             (memq (car lambda-list)
2391                                   specialized-lambda-list-keywords)
2392                             (not (or (null (cadr lambda-list))
2393                                      (memq (cadr lambda-list)
2394                                            specialized-lambda-list-keywords)))))
2395                (error 'specialized-lambda-list-error
2396                       :format-control
2397                       "in a specialized-lambda-list, excactly one ~
2398                        variable must follow &REST.~%"
2399                       :format-arguments nil))
2400              (values parameters
2401                      (cons arg lambda-list)
2402                      ()
2403                      ())))
2404           (supplied-keywords
2405            ;; After a lambda-list keyword there can be no specializers.
2406            (multiple-value-bind (parameters lambda-list)
2407                (parse-specialized-lambda-list (cdr arglist)
2408                                               supplied-keywords
2409                                               allowed-keywords)
2410              (values (cons (if (listp arg) (car arg) arg) parameters)
2411                      (cons arg lambda-list)
2412                      ()
2413                      ())))
2414           (t
2415            (multiple-value-bind (parameters lambda-list specializers required)
2416                (parse-specialized-lambda-list (cdr arglist))
2417              (values (cons (if (listp arg) (car arg) arg) parameters)
2418                      (cons (if (listp arg) (car arg) arg) lambda-list)
2419                      (cons (if (listp arg) (cadr arg) t) specializers)
2420                      (cons (if (listp arg) (car arg) arg) required)))))))
2421 \f
2422 (setq *boot-state* 'early)
2423 \f
2424 ;;; FIXME: In here there was a #-CMU definition of SYMBOL-MACROLET
2425 ;;; which used %WALKER stuff. That suggests to me that maybe the code
2426 ;;; walker stuff was only used for implementing stuff like that; maybe
2427 ;;; it's not needed any more? Hunt down what it was used for and see.
2428
2429 (defmacro with-slots (slots instance &body body)
2430   (let ((in (gensym)))
2431     `(let ((,in ,instance))
2432        (declare (ignorable ,in))
2433        ,@(let ((instance (if (and (consp instance) (eq (car instance) 'the))
2434                              (third instance)
2435                              instance)))
2436            (and (symbolp instance)
2437                 `((declare (%variable-rebinding ,in ,instance)))))
2438        ,in
2439        (symbol-macrolet ,(mapcar (lambda (slot-entry)
2440                                    (let ((var-name
2441                                           (if (symbolp slot-entry)
2442                                               slot-entry
2443                                               (car slot-entry)))
2444                                          (slot-name
2445                                           (if (symbolp slot-entry)
2446                                               slot-entry
2447                                               (cadr slot-entry))))
2448                                      `(,var-name
2449                                        (slot-value ,in ',slot-name))))
2450                                  slots)
2451                         ,@body))))
2452
2453 (defmacro with-accessors (slots instance &body body)
2454   (let ((in (gensym)))
2455     `(let ((,in ,instance))
2456        (declare (ignorable ,in))
2457        ,@(let ((instance (if (and (consp instance) (eq (car instance) 'the))
2458                              (third instance)
2459                              instance)))
2460            (and (symbolp instance)
2461                 `((declare (%variable-rebinding ,in ,instance)))))
2462        ,in
2463        (symbol-macrolet ,(mapcar (lambda (slot-entry)
2464                                    (let ((var-name (car slot-entry))
2465                                          (accessor-name (cadr slot-entry)))
2466                                      `(,var-name (,accessor-name ,in))))
2467                                  slots)
2468           ,@body))))