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 (declaim (notinline make-a-method
  72                     add-named-method
  73                     ensure-generic-function-using-class
  74                     add-method
  75                     remove-method))
  76
  77 (defvar *!early-functions*
  78         '((make-a-method early-make-a-method
  79                          real-make-a-method)
  80           (add-named-method early-add-named-method
  81                             real-add-named-method)
  82           ))
  83
  84 ;;; For each of the early functions, arrange to have it point to its
  85 ;;; early definition. Do this in a way that makes sure that if we
  86 ;;; redefine one of the early definitions the redefinition will take
  87 ;;; effect. This makes development easier.
  88 (dolist (fns *!early-functions*)
  89   (let ((name (car fns))
  90         (early-name (cadr fns)))
  91     (setf (gdefinition name)
  92             (set-fun-name
  93              (lambda (&rest args)
  94                (apply (fdefinition early-name) args))
  95              name))))
  96
  97 ;;; *!GENERIC-FUNCTION-FIXUPS* is used by !FIX-EARLY-GENERIC-FUNCTIONS
  98 ;;; to convert the few functions in the bootstrap which are supposed
  99 ;;; to be generic functions but can't be early on.
 100 (defvar *!generic-function-fixups*
 101   '((add-method
 102      ((generic-function method)  ;lambda-list
 103       (standard-generic-function method) ;specializers
 104       real-add-method))          ;method-function
 105     (remove-method
 106      ((generic-function method)
 107       (standard-generic-function method)
 108       real-remove-method))
 109     (get-method
 110      ((generic-function qualifiers specializers &optional (errorp t))
 111       (standard-generic-function t t)
 112       real-get-method))
 113     (ensure-generic-function-using-class
 114      ((generic-function fun-name
 115                         &key generic-function-class environment
 116                         &allow-other-keys)
 117       (generic-function t)
 118       real-ensure-gf-using-class--generic-function)
 119      ((generic-function fun-name
 120                         &key generic-function-class environment
 121                         &allow-other-keys)
 122       (null t)
 123       real-ensure-gf-using-class--null))
 124     (make-method-lambda
 125      ((proto-generic-function proto-method lambda-expression environment)
 126       (standard-generic-function standard-method t t)
 127       real-make-method-lambda))
 128     (make-method-initargs-form
 129      ((proto-generic-function proto-method
 130                               lambda-expression
 131                               lambda-list environment)
 132       (standard-generic-function standard-method t t t)
 133       real-make-method-initargs-form))
 134     (compute-effective-method
 135      ((generic-function combin applicable-methods)
 136       (generic-function standard-method-combination t)
 137       standard-compute-effective-method))))
 138 \f
 139 (defmacro defgeneric (fun-name lambda-list &body options)
 140   (declare (type list lambda-list))
 141   (unless (legal-fun-name-p fun-name)
 142     (error 'simple-program-error
 143            :format-control "illegal generic function name ~S"
 144            :format-arguments (list fun-name)))
 145   (check-gf-lambda-list lambda-list)
 146   (let ((initargs ())
 147         (methods ()))
 148     (flet ((duplicate-option (name)
 149              (error 'simple-program-error
 150                     :format-control "The option ~S appears more than once."
 151                     :format-arguments (list name)))
 152            (expand-method-definition (qab) ; QAB = qualifiers, arglist, body
 153              (let* ((arglist-pos (position-if #'listp qab))
 154                     (arglist (elt qab arglist-pos))
 155                     (qualifiers (subseq qab 0 arglist-pos))
 156                     (body (nthcdr (1+ arglist-pos) qab)))
 157                `(push (defmethod ,fun-name ,@qualifiers ,arglist ,@body)
 158                       (generic-function-initial-methods (fdefinition ',fun-name))))))
 159       (macrolet ((initarg (key) `(getf initargs ,key)))
 160         (dolist (option options)
 161           (let ((car-option (car option)))
 162             (case car-option
 163               (declare
 164                (when (and
 165                       (consp (cadr option))
 166                       (member (first (cadr option))
 167                               ;; FIXME: this list is slightly weird.
 168                               ;; ANSI (on the DEFGENERIC page) in one
 169                               ;; place allows only OPTIMIZE; in
 170                               ;; another place gives this list of
 171                               ;; disallowed declaration specifiers.
 172                               ;; This seems to be the only place where
 173                               ;; the FUNCTION declaration is
 174                               ;; mentioned; TYPE seems to be missing.
 175                               ;; Very strange.  -- CSR, 2002-10-21
 176                               '(declaration ftype function
 177                                 inline notinline special)))
 178                  (error 'simple-program-error
 179                         :format-control "The declaration specifier ~S ~
 180                                          is not allowed inside DEFGENERIC."
 181                         :format-arguments (list (cadr option))))
 182                (push (cadr option) (initarg :declarations)))
 183               (:method-combination
 184                (when (initarg car-option)
 185                  (duplicate-option car-option))
 186                (unless (symbolp (cadr option))
 187                  (error 'simple-program-error
 188                         :format-control "METHOD-COMBINATION name not a ~
 189                                          symbol: ~S"
 190                         :format-arguments (list (cadr option))))
 191                (setf (initarg car-option)
 192                      `',(cdr option)))
 193               (:argument-precedence-order
 194                (let* ((required (parse-lambda-list lambda-list))
 195                       (supplied (cdr option)))
 196                  (unless (= (length required) (length supplied))
 197                    (error 'simple-program-error
 198                           :format-control "argument count discrepancy in ~
 199                                            :ARGUMENT-PRECEDENCE-ORDER clause."
 200                           :format-arguments nil))
 201                  (when (set-difference required supplied)
 202                    (error 'simple-program-error
 203                           :format-control "unequal sets for ~
 204                                            :ARGUMENT-PRECEDENCE-ORDER clause: ~
 205                                            ~S and ~S"
 206                           :format-arguments (list required supplied)))
 207                  (setf (initarg car-option)
 208                        `',(cdr option))))
 209               ((:documentation :generic-function-class :method-class)
 210                (unless (proper-list-of-length-p option 2)
 211                  (error "bad list length for ~S" option))
 212                (if (initarg car-option)
 213                    (duplicate-option car-option)
 214                    (setf (initarg car-option) `',(cadr option))))
 215               (:method
 216                (push (cdr option) methods))
 217               (t
 218                ;; ANSI requires that unsupported things must get a
 219                ;; PROGRAM-ERROR.
 220                (error 'simple-program-error
 221                       :format-control "unsupported option ~S"
 222                       :format-arguments (list option))))))
 223
 224         (when (initarg :declarations)
 225           (setf (initarg :declarations)
 226                 `',(initarg :declarations))))
 227       `(progn
 228          (eval-when (:compile-toplevel :load-toplevel :execute)
 229            (compile-or-load-defgeneric ',fun-name))
 230          (load-defgeneric ',fun-name ',lambda-list
 231                           (sb-c:source-location) ,@initargs)
 232         ,@(mapcar #'expand-method-definition methods)
 233         (fdefinition ',fun-name)))))
 234
 235 (defun compile-or-load-defgeneric (fun-name)
 236   (proclaim-as-fun-name fun-name)
 237   (note-name-defined fun-name :function)
 238   (unless (eq (info :function :where-from fun-name) :declared)
 239     (setf (info :function :where-from fun-name) :defined)
 240     (setf (info :function :type fun-name)
 241           (specifier-type 'function))))
 242
 243 (defun load-defgeneric (fun-name lambda-list source-location &rest initargs)
 244   (when (fboundp fun-name)
 245     (style-warn "redefining ~S in DEFGENERIC" fun-name)
 246     (let ((fun (fdefinition fun-name)))
 247       (when (generic-function-p fun)
 248         (loop for method in (generic-function-initial-methods fun)
 249               do (remove-method fun method))
 250         (setf (generic-function-initial-methods fun) '()))))
 251   (apply #'ensure-generic-function
 252          fun-name
 253          :lambda-list lambda-list
 254          :definition-source source-location
 255          initargs))
 256
 257 (define-condition generic-function-lambda-list-error
 258     (reference-condition simple-program-error)
 259   ()
 260   (:default-initargs :references (list '(:ansi-cl :section (3 4 2)))))
 261
 262 (defun check-gf-lambda-list (lambda-list)
 263   (flet ((ensure (arg ok)
 264            (unless ok
 265              (error 'generic-function-lambda-list-error
 266                     :format-control
 267                     "~@<invalid ~S ~_in the generic function lambda list ~S~:>"
 268                     :format-arguments (list arg lambda-list)))))
 269     (multiple-value-bind (required optional restp rest keyp keys allowp
 270                           auxp aux morep more-context more-count)
 271         (parse-lambda-list lambda-list)
 272       (declare (ignore required)) ; since they're no different in a gf ll
 273       (declare (ignore restp rest)) ; since they're no different in a gf ll
 274       (declare (ignore allowp)) ; since &ALLOW-OTHER-KEYS is fine either way
 275       (declare (ignore aux)) ; since we require AUXP=NIL
 276       (declare (ignore more-context more-count)) ; safely ignored unless MOREP
 277       ;; no defaults allowed for &OPTIONAL arguments
 278       (dolist (i optional)
 279         (ensure i (or (symbolp i)
 280                       (and (consp i) (symbolp (car i)) (null (cdr i))))))
 281       ;; no defaults allowed for &KEY arguments
 282       (when keyp
 283         (dolist (i keys)
 284           (ensure i (or (symbolp i)
 285                         (and (consp i)
 286                              (or (symbolp (car i))
 287                                  (and (consp (car i))
 288                                       (symbolp (caar i))
 289                                       (symbolp (cadar i))
 290                                       (null (cddar i))))
 291                              (null (cdr i)))))))
 292       ;; no &AUX allowed
 293       (when auxp
 294         (error "&AUX is not allowed in a generic function lambda list: ~S"
 295                lambda-list))
 296       ;; Oh, *puhlease*... not specifically as per section 3.4.2 of
 297       ;; the ANSI spec, but the CMU CL &MORE extension does not
 298       ;; belong here!
 299       (aver (not morep)))))
 300 \f
 301 (defmacro defmethod (&rest args &environment env)
 302   (multiple-value-bind (name qualifiers lambda-list body)
 303       (parse-defmethod args)
 304     (multiple-value-bind (proto-gf proto-method)
 305         (prototypes-for-make-method-lambda name)
 306       (expand-defmethod name
 307                         proto-gf
 308                         proto-method
 309                         qualifiers
 310                         lambda-list
 311                         body
 312                         env))))
 313
 314 (defun prototypes-for-make-method-lambda (name)
 315   (if (not (eq *boot-state* 'complete))
 316       (values nil nil)
 317       (let ((gf? (and (fboundp name)
 318                       (gdefinition name))))
 319         (if (or (null gf?)
 320                 (not (generic-function-p gf?)))
 321             (values (class-prototype (find-class 'standard-generic-function))
 322                     (class-prototype (find-class 'standard-method)))
 323             (values gf?
 324                     (class-prototype (or (generic-function-method-class gf?)
 325                                          (find-class 'standard-method))))))))
 326
 327 ;;; Take a name which is either a generic function name or a list specifying
 328 ;;; a SETF generic function (like: (SETF <generic-function-name>)). Return
 329 ;;; the prototype instance of the method-class for that generic function.
 330 ;;;
 331 ;;; If there is no generic function by that name, this returns the
 332 ;;; default value, the prototype instance of the class
 333 ;;; STANDARD-METHOD. This default value is also returned if the spec
 334 ;;; names an ordinary function or even a macro. In effect, this leaves
 335 ;;; the signalling of the appropriate error until load time.
 336 ;;;
 337 ;;; Note: During bootstrapping, this function is allowed to return NIL.
 338 (defun method-prototype-for-gf (name)
 339   (let ((gf? (and (fboundp name)
 340                   (gdefinition name))))
 341     (cond ((neq *boot-state* 'complete) nil)
 342           ((or (null gf?)
 343                (not (generic-function-p gf?)))          ; Someone else MIGHT
 344                                                         ; error at load time.
 345            (class-prototype (find-class 'standard-method)))
 346           (t
 347             (class-prototype (or (generic-function-method-class gf?)
 348                                  (find-class 'standard-method)))))))
 349 \f
 350 (defun expand-defmethod (name
 351                          proto-gf
 352                          proto-method
 353                          qualifiers
 354                          lambda-list
 355                          body
 356                          env)
 357   (multiple-value-bind (method-lambda unspecialized-lambda-list specializers)
 358       (add-method-declarations name qualifiers lambda-list body env)
 359     (multiple-value-bind (method-function-lambda initargs)
 360         (make-method-lambda proto-gf proto-method method-lambda env)
 361       (let ((initargs-form (make-method-initargs-form proto-gf
 362                                                       proto-method
 363                                                       method-function-lambda
 364                                                       initargs
 365                                                       env)))
 366         `(progn
 367           ;; Note: We could DECLAIM the ftype of the generic function
 368           ;; here, since ANSI specifies that we create it if it does
 369           ;; not exist. However, I chose not to, because I think it's
 370           ;; more useful to support a style of programming where every
 371           ;; generic function has an explicit DEFGENERIC and any typos
 372           ;; in DEFMETHODs are warned about. Otherwise
 373           ;;
 374           ;;   (DEFGENERIC FOO-BAR-BLETCH ((X T)))
 375           ;;   (DEFMETHOD FOO-BAR-BLETCH ((X HASH-TABLE)) ..)
 376           ;;   (DEFMETHOD FOO-BRA-BLETCH ((X SIMPLE-VECTOR)) ..)
 377           ;;   (DEFMETHOD FOO-BAR-BLETCH ((X VECTOR)) ..)
 378           ;;   (DEFMETHOD FOO-BAR-BLETCH ((X ARRAY)) ..)
 379           ;;   (DEFMETHOD FOO-BAR-BLETCH ((X LIST)) ..)
 380           ;;
 381           ;; compiles without raising an error and runs without
 382           ;; raising an error (since SIMPLE-VECTOR cases fall through
 383           ;; to VECTOR) but still doesn't do what was intended. I hate
 384           ;; that kind of bug (code which silently gives the wrong
 385           ;; answer), so we don't do a DECLAIM here. -- WHN 20000229
 386           ,(make-defmethod-form name qualifiers specializers
 387                                 unspecialized-lambda-list
 388                                 (if proto-method
 389                                     (class-name (class-of proto-method))
 390                                     'standard-method)
 391                                 initargs-form
 392                                 (getf (getf initargs :plist)
 393                                       :pv-table-symbol)))))))
 394
 395 (defun interned-symbol-p (x)
 396   (and (symbolp x) (symbol-package x)))
 397
 398 (defun make-defmethod-form (name qualifiers specializers
 399                                  unspecialized-lambda-list method-class-name
 400                                  initargs-form &optional pv-table-symbol)
 401   (let (fn
 402         fn-lambda)
 403     (if (and (interned-symbol-p (fun-name-block-name name))
 404              (every #'interned-symbol-p qualifiers)
 405              (every (lambda (s)
 406                       (if (consp s)
 407                           (and (eq (car s) 'eql)
 408                                (constantp (cadr s))
 409                                (let ((sv (constant-form-value (cadr s))))
 410                                  (or (interned-symbol-p sv)
 411                                      (integerp sv)
 412                                      (and (characterp sv)
 413                                           (standard-char-p sv)))))
 414                           (interned-symbol-p s)))
 415                     specializers)
 416              (consp initargs-form)
 417              (eq (car initargs-form) 'list*)
 418              (memq (cadr initargs-form) '(:function :fast-function))
 419              (consp (setq fn (caddr initargs-form)))
 420              (eq (car fn) 'function)
 421              (consp (setq fn-lambda (cadr fn)))
 422              (eq (car fn-lambda) 'lambda))
 423         (let* ((specls (mapcar (lambda (specl)
 424                                  (if (consp specl)
 425                                      `(,(car specl) ,(eval (cadr specl)))
 426                                    specl))
 427                                specializers))
 428                (mname `(,(if (eq (cadr initargs-form) :function)
 429                              'slow-method 'fast-method)
 430                         ,name ,@qualifiers ,specls)))
 431           `(progn
 432              (defun ,mname ,(cadr fn-lambda)
 433                ,@(cddr fn-lambda))
 434              ,(make-defmethod-form-internal
 435                name qualifiers `',specls
 436                unspecialized-lambda-list method-class-name
 437                `(list* ,(cadr initargs-form)
 438                        #',mname
 439                        ,@(cdddr initargs-form))
 440                pv-table-symbol)))
 441         (make-defmethod-form-internal
 442          name qualifiers
 443          `(list ,@(mapcar (lambda (specializer)
 444                             (if (consp specializer)
 445                                 ``(,',(car specializer)
 446                                       ,,(cadr specializer))
 447                                 `',specializer))
 448                           specializers))
 449          unspecialized-lambda-list
 450          method-class-name
 451          initargs-form
 452          pv-table-symbol))))
 453
 454 (defun make-defmethod-form-internal
 455     (name qualifiers specializers-form unspecialized-lambda-list
 456      method-class-name initargs-form &optional pv-table-symbol)
 457   `(load-defmethod
 458     ',method-class-name
 459     ',name
 460     ',qualifiers
 461     ,specializers-form
 462     ',unspecialized-lambda-list
 463     ,initargs-form
 464     ;; Paper over a bug in KCL by passing the cache-symbol here in
 465     ;; addition to in the list. FIXME: We should no longer need to do
 466     ;; this, since the CLOS code is now SBCL-specific, and doesn't
 467     ;; need to be ported to every buggy compiler in existence.
 468     ',pv-table-symbol
 469     (sb-c:source-location)))
 470
 471 (defmacro make-method-function (method-lambda &environment env)
 472   (make-method-function-internal method-lambda env))
 473
 474 (defun make-method-function-internal (method-lambda &optional env)
 475   (multiple-value-bind (proto-gf proto-method)
 476       (prototypes-for-make-method-lambda nil)
 477     (multiple-value-bind (method-function-lambda initargs)
 478         (make-method-lambda proto-gf proto-method method-lambda env)
 479       (make-method-initargs-form proto-gf
 480                                  proto-method
 481                                  method-function-lambda
 482                                  initargs
 483                                  env))))
 484
 485 (defun add-method-declarations (name qualifiers lambda-list body env)
 486   (declare (ignore env))
 487   (multiple-value-bind (parameters unspecialized-lambda-list specializers)
 488       (parse-specialized-lambda-list lambda-list)
 489     (multiple-value-bind (real-body declarations documentation)
 490         (parse-body body)
 491       (values `(lambda ,unspecialized-lambda-list
 492                  ,@(when documentation `(,documentation))
 493                  ;; (Old PCL code used a somewhat different style of
 494                  ;; list for %METHOD-NAME values. Our names use
 495                  ;; ,@QUALIFIERS instead of ,QUALIFIERS so that the
 496                  ;; method names look more like what you see in a
 497                  ;; DEFMETHOD form.)
 498                  ;;
 499                  ;; FIXME: As of sbcl-0.7.0.6, code elsewhere, at
 500                  ;; least the code to set up named BLOCKs around the
 501                  ;; bodies of methods, depends on the function's base
 502                  ;; name being the first element of the %METHOD-NAME
 503                  ;; list. It would be good to remove this dependency,
 504                  ;; perhaps by building the BLOCK here, or by using
 505                  ;; another declaration (e.g. %BLOCK-NAME), so that
 506                  ;; our method debug names are free to have any format,
 507                  ;; e.g. (:METHOD PRINT-OBJECT :AROUND (CLOWN T)).
 508                  ;;
 509                  ;; Further, as of sbcl-0.7.9.10, the code to
 510                  ;; implement NO-NEXT-METHOD is coupled to the form of
 511                  ;; this declaration; see the definition of
 512                  ;; CALL-NO-NEXT-METHOD (and the passing of
 513                  ;; METHOD-NAME-DECLARATION arguments around the
 514                  ;; various CALL-NEXT-METHOD logic).
 515                  (declare (%method-name (,name
 516                                          ,@qualifiers
 517                                          ,specializers)))
 518                  (declare (%method-lambda-list ,@lambda-list))
 519                  ,@declarations
 520                  ,@real-body)
 521               unspecialized-lambda-list specializers))))
 522
 523 (defun real-make-method-initargs-form (proto-gf proto-method
 524                                        method-lambda initargs env)
 525   (declare (ignore proto-gf proto-method))
 526   (unless (and (consp method-lambda)
 527                (eq (car method-lambda) 'lambda))
 528     (error "The METHOD-LAMBDA argument to MAKE-METHOD-FUNCTION, ~S, ~
 529             is not a lambda form."
 530            method-lambda))
 531   (make-method-initargs-form-internal method-lambda initargs env))
 532
 533 (unless (fboundp 'make-method-initargs-form)
 534   (setf (gdefinition 'make-method-initargs-form)
 535         (symbol-function 'real-make-method-initargs-form)))
 536
 537 (defun real-make-method-lambda (proto-gf proto-method method-lambda env)
 538   (declare (ignore proto-gf proto-method))
 539   (make-method-lambda-internal method-lambda env))
 540
 541 ;;; a helper function for creating Python-friendly type declarations
 542 ;;; in DEFMETHOD forms
 543 (defun parameter-specializer-declaration-in-defmethod (parameter specializer)
 544   (cond ((and (consp specializer)
 545               (eq (car specializer) 'eql))
 546          ;; KLUDGE: ANSI, in its wisdom, says that
 547          ;; EQL-SPECIALIZER-FORMs in EQL specializers are evaluated at
 548          ;; DEFMETHOD expansion time. Thus, although one might think
 549          ;; that in
 550          ;;   (DEFMETHOD FOO ((X PACKAGE)
 551          ;;                   (Y (EQL 12))
 552          ;;      ..))
 553          ;; the PACKAGE and (EQL 12) forms are both parallel type
 554          ;; names, they're not, as is made clear when you do
 555          ;;   (DEFMETHOD FOO ((X PACKAGE)
 556          ;;                   (Y (EQL 'BAR)))
 557          ;;     ..)
 558          ;; where Y needs to be a symbol named "BAR", not some cons
 559          ;; made by (CONS 'QUOTE 'BAR). I.e. when the
 560          ;; EQL-SPECIALIZER-FORM is (EQL 'X), it requires an argument
 561          ;; to be of type (EQL X). It'd be easy to transform one to
 562          ;; the other, but it'd be somewhat messier to do so while
 563          ;; ensuring that the EQL-SPECIALIZER-FORM is only EVAL'd
 564          ;; once. (The new code wouldn't be messy, but it'd require a
 565          ;; big transformation of the old code.) So instead we punt.
 566          ;; -- WHN 20000610
 567          '(ignorable))
 568         ((member specializer
 569                  ;; KLUDGE: For some low-level implementation
 570                  ;; classes, perhaps because of some problems related
 571                  ;; to the incomplete integration of PCL into SBCL's
 572                  ;; type system, some specializer classes can't be
 573                  ;; declared as argument types. E.g.
 574                  ;;   (DEFMETHOD FOO ((X SLOT-OBJECT))
 575                  ;;     (DECLARE (TYPE SLOT-OBJECT X))
 576                  ;;     ..)
 577                  ;; loses when
 578                  ;;   (DEFSTRUCT BAR A B)
 579                  ;;   (FOO (MAKE-BAR))
 580                  ;; perhaps because of the way that STRUCTURE-OBJECT
 581                  ;; inherits both from SLOT-OBJECT and from
 582                  ;; SB-KERNEL:INSTANCE. In an effort to sweep such
 583                  ;; problems under the rug, we exclude these problem
 584                  ;; cases by blacklisting them here. -- WHN 2001-01-19
 585                  (list 'slot-object #+nil (find-class 'slot-object)))
 586          '(ignorable))
 587         ((not (eq *boot-state* 'complete))
 588          ;; KLUDGE: PCL, in its wisdom, sometimes calls methods with
 589          ;; types which don't match their specializers. (Specifically,
 590          ;; it calls ENSURE-CLASS-USING-CLASS (T NULL) with a non-NULL
 591          ;; second argument.) Hopefully it only does this kind of
 592          ;; weirdness when bootstrapping.. -- WHN 20000610
 593          '(ignorable))
 594         ((typep specializer 'eql-specializer)
 595          `(type (eql ,(eql-specializer-object specializer)) ,parameter))
 596         ((var-globally-special-p parameter)
 597          ;; KLUDGE: Don't declare types for global special variables
 598          ;; -- our rebinding magic for SETQ cases don't work right
 599          ;; there.
 600          ;;
 601          ;; FIXME: It would be better to detect the SETQ earlier and
 602          ;; skip declarations for specials only when needed, not
 603          ;; always.
 604          ;;
 605          ;; --NS 2004-10-14
 606          '(ignorable))
 607         (t
 608          ;; Otherwise, we can usually make Python very happy.
 609          ;;
 610          ;; KLUDGE: Since INFO doesn't work right for class objects here,
 611          ;; and they are valid specializers, see if the specializer is
 612          ;; a named class, and use the name in that case -- otherwise
 613          ;; the class instance is ok, since info will just return NIL, NIL.
 614          ;;
 615          ;; We still need to deal with the class case too, but at
 616          ;; least #.(find-class 'integer) and integer as equivalent
 617          ;; specializers with this.
 618          (let* ((specializer (if (and (typep specializer 'class)
 619                                       (let ((name (class-name specializer)))
 620                                         (and name (symbolp name)
 621                                              (eq specializer (find-class name nil)))))
 622                                  (class-name specializer)
 623                                  specializer))
 624                 (kind (info :type :kind specializer)))
 625
 626            (flet ((specializer-class ()
 627                     (if (typep specializer 'class)
 628                         specializer
 629                         (find-class specializer nil))))
 630              (ecase kind
 631                ((:primitive) `(type ,specializer ,parameter))
 632                ((:defined)
 633                 (let ((class (specializer-class)))
 634                   ;; CLASS can be null here if the user has erroneously
 635                  ;; tried to use a defined type as a specializer; it
 636                  ;; can be a non-BUILT-IN-CLASS if the user defines a
 637                  ;; type and calls (SETF FIND-CLASS) in a consistent
 638                  ;; way.
 639                  (when (and class (typep class 'built-in-class))
 640                    `(type ,specializer ,parameter))))
 641               ((:instance nil)
 642                (let ((class (specializer-class)))
 643                  (cond
 644                    (class
 645                     (if (typep class '(or built-in-class structure-class))
 646                         `(type ,specializer ,parameter)
 647                         ;; don't declare CLOS classes as parameters;
 648                         ;; it's too expensive.
 649                         '(ignorable)))
 650                    (t
 651                     ;; we can get here, and still not have a failure
 652                     ;; case, by doing MOP programming like (PROGN
 653                     ;; (ENSURE-CLASS 'FOO) (DEFMETHOD BAR ((X FOO))
 654                     ;; ...)).  Best to let the user know we haven't
 655                     ;; been able to extract enough information:
 656                     (style-warn
 657                      "~@<can't find type for presumed class ~S in ~S.~@:>"
 658                      specializer
 659                      'parameter-specializer-declaration-in-defmethod)
 660                     '(ignorable)))))
 661               ((:forthcoming-defclass-type)
 662                '(ignorable))))))))
 663
 664 (defun make-method-lambda-internal (method-lambda &optional env)
 665   (unless (and (consp method-lambda) (eq (car method-lambda) 'lambda))
 666     (error "The METHOD-LAMBDA argument to MAKE-METHOD-LAMBDA, ~S, ~
 667             is not a lambda form."
 668            method-lambda))
 669   (multiple-value-bind (real-body declarations documentation)
 670       (parse-body (cddr method-lambda))
 671     (let* ((name-decl (get-declaration '%method-name declarations))
 672            (sll-decl (get-declaration '%method-lambda-list declarations))
 673            (method-name (when (consp name-decl) (car name-decl)))
 674            (generic-function-name (when method-name (car method-name)))
 675            (specialized-lambda-list (or sll-decl (cadr method-lambda))))
 676       (multiple-value-bind (parameters lambda-list specializers)
 677           (parse-specialized-lambda-list specialized-lambda-list)
 678         (let* ((required-parameters
 679                 (mapcar (lambda (r s) (declare (ignore s)) r)
 680                         parameters
 681                         specializers))
 682                (slots (mapcar #'list required-parameters))
 683                (calls (list nil))
 684                (class-declarations
 685                 `(declare
 686                   ;; These declarations seem to be used by PCL to pass
 687                   ;; information to itself; when I tried to delete 'em
 688                   ;; ca. 0.6.10 it didn't work. I'm not sure how
 689                   ;; they work, but note the (VAR-DECLARATION '%CLASS ..)
 690                   ;; expression in CAN-OPTIMIZE-ACCESS1. -- WHN 2000-12-30
 691                   ,@(remove nil
 692                             (mapcar (lambda (a s) (and (symbolp s)
 693                                                        (neq s t)
 694                                                        `(%class ,a ,s)))
 695                                     parameters
 696                                     specializers))
 697                   ;; These TYPE declarations weren't in the original
 698                   ;; PCL code, but the Python compiler likes them a
 699                   ;; lot. (We're telling the compiler about our
 700                   ;; knowledge of specialized argument types so that
 701                   ;; it can avoid run-time type dispatch overhead,
 702                   ;; which can be a huge win for Python.)
 703                   ;;
 704                   ;; KLUDGE: when I tried moving these to
 705                   ;; ADD-METHOD-DECLARATIONS, things broke.  No idea
 706                   ;; why.  -- CSR, 2004-06-16
 707                   ,@(mapcar #'parameter-specializer-declaration-in-defmethod
 708                             parameters
 709                             specializers)))
 710                (method-lambda
 711                 ;; Remove the documentation string and insert the
 712                 ;; appropriate class declarations. The documentation
 713                 ;; string is removed to make it easy for us to insert
 714                 ;; new declarations later, they will just go after the
 715                 ;; CADR of the method lambda. The class declarations
 716                 ;; are inserted to communicate the class of the method's
 717                 ;; arguments to the code walk.
 718                 `(lambda ,lambda-list
 719                    ;; The default ignorability of method parameters
 720                    ;; doesn't seem to be specified by ANSI. PCL had
 721                    ;; them basically ignorable but was a little
 722                    ;; inconsistent. E.g. even though the two
 723                    ;; method definitions
 724                    ;;   (DEFMETHOD FOO ((X T) (Y T)) "Z")
 725                    ;;   (DEFMETHOD FOO ((X T) Y) "Z")
 726                    ;; are otherwise equivalent, PCL treated Y as
 727                    ;; ignorable in the first definition but not in the
 728                    ;; second definition. We make all required
 729                    ;; parameters ignorable as a way of systematizing
 730                    ;; the old PCL behavior. -- WHN 2000-11-24
 731                    (declare (ignorable ,@required-parameters))
 732                    ,class-declarations
 733                    ,@declarations
 734                    (block ,(fun-name-block-name generic-function-name)
 735                      ,@real-body)))
 736                (constant-value-p (and (null (cdr real-body))
 737                                       (constantp (car real-body))))
 738                (constant-value (and constant-value-p
 739                                     (constant-form-value (car real-body))))
 740                (plist (and constant-value-p
 741                            (or (typep constant-value
 742                                       '(or number character))
 743                                (and (symbolp constant-value)
 744                                     (symbol-package constant-value)))
 745                            (list :constant-value constant-value)))
 746                (applyp (dolist (p lambda-list nil)
 747                          (cond ((memq p '(&optional &rest &key))
 748                                 (return t))
 749                                ((eq p '&aux)
 750                                 (return nil))))))
 751           (multiple-value-bind
 752                 (walked-lambda call-next-method-p closurep
 753                                next-method-p-p setq-p)
 754               (walk-method-lambda method-lambda
 755                                   required-parameters
 756                                   env
 757                                   slots
 758                                   calls)
 759             (multiple-value-bind (walked-lambda-body
 760                                   walked-declarations
 761                                   walked-documentation)
 762                 (parse-body (cddr walked-lambda))
 763               (declare (ignore walked-documentation))
 764               (when (or next-method-p-p call-next-method-p)
 765                 (setq plist (list* :needs-next-methods-p t plist)))
 766               (when (some #'cdr slots)
 767                 (multiple-value-bind (slot-name-lists call-list)
 768                     (slot-name-lists-from-slots slots calls)
 769                   (let ((pv-table-symbol (make-symbol "pv-table")))
 770                     (setq plist
 771                           `(,@(when slot-name-lists
 772                                     `(:slot-name-lists ,slot-name-lists))
 773                               ,@(when call-list
 774                                       `(:call-list ,call-list))
 775                               :pv-table-symbol ,pv-table-symbol
 776                               ,@plist))
 777                     (setq walked-lambda-body
 778                           `((pv-binding (,required-parameters
 779                                          ,slot-name-lists
 780                                          ,pv-table-symbol)
 781                               ,@walked-lambda-body))))))
 782               (when (and (memq '&key lambda-list)
 783                          (not (memq '&allow-other-keys lambda-list)))
 784                 (let ((aux (memq '&aux lambda-list)))
 785                   (setq lambda-list (nconc (ldiff lambda-list aux)
 786                                            (list '&allow-other-keys)
 787                                            aux))))
 788               (values `(lambda (.method-args. .next-methods.)
 789                          (simple-lexical-method-functions
 790                              (,lambda-list .method-args. .next-methods.
 791                                            :call-next-method-p
 792                                            ,call-next-method-p
 793                                            :next-method-p-p ,next-method-p-p
 794                                            :setq-p ,setq-p
 795                                            ;; we need to pass this along
 796                                            ;; so that NO-NEXT-METHOD can
 797                                            ;; be given a suitable METHOD
 798                                            ;; argument; we need the
 799                                            ;; QUALIFIERS and SPECIALIZERS
 800                                            ;; inside the declaration to
 801                                            ;; give to FIND-METHOD.
 802                                            :method-name-declaration ,name-decl
 803                                            :closurep ,closurep
 804                                            :applyp ,applyp)
 805                            ,@walked-declarations
 806                            ,@walked-lambda-body))
 807                       `(,@(when plist
 808                                 `(:plist ,plist))
 809                           ,@(when documentation
 810                                   `(:documentation ,documentation)))))))))))
 811
 812 (unless (fboundp 'make-method-lambda)
 813   (setf (gdefinition 'make-method-lambda)
 814         (symbol-function 'real-make-method-lambda)))
 815
 816 (defmacro simple-lexical-method-functions ((lambda-list
 817                                             method-args
 818                                             next-methods
 819                                             &rest lmf-options)
 820                                            &body body)
 821   `(progn
 822      ,method-args ,next-methods
 823      (bind-simple-lexical-method-functions (,method-args ,next-methods
 824                                                          ,lmf-options)
 825          (bind-args (,lambda-list ,method-args)
 826            ,@body))))
 827
 828 (defmacro fast-lexical-method-functions ((lambda-list
 829                                           next-method-call
 830                                           args
 831                                           rest-arg
 832                                           &rest lmf-options)
 833                                          &body body)
 834   `(bind-fast-lexical-method-functions (,args ,rest-arg ,next-method-call ,lmf-options)
 835      (bind-args (,(nthcdr (length args) lambda-list) ,rest-arg)
 836        ,@body)))
 837
 838 (defmacro bind-simple-lexical-method-functions
 839     ((method-args next-methods (&key call-next-method-p next-method-p-p setq-p
 840                                      closurep applyp method-name-declaration))
 841      &body body
 842      &environment env)
 843   (if (not (or call-next-method-p setq-p closurep next-method-p-p applyp))
 844       `(locally
 845            ,@body)
 846       `(let ((.next-method. (car ,next-methods))
 847              (,next-methods (cdr ,next-methods)))
 848          (declare (ignorable .next-method. ,next-methods))
 849          (flet (,@(and call-next-method-p
 850                        `((call-next-method
 851                           (&rest cnm-args)
 852                           ,@(if (safe-code-p env)
 853                                 `((%check-cnm-args cnm-args
 854                                                    ,method-args
 855                                                    ',method-name-declaration))
 856                                 nil)
 857                           (if .next-method.
 858                               (funcall (if (std-instance-p .next-method.)
 859                                            (method-function .next-method.)
 860                                            .next-method.) ; for early methods
 861                                        (or cnm-args ,method-args)
 862                                        ,next-methods)
 863                               (apply #'call-no-next-method
 864                                      ',method-name-declaration
 865                                      (or cnm-args ,method-args))))))
 866                 ,@(and next-method-p-p
 867                        '((next-method-p ()
 868                           (not (null .next-method.))))))
 869            ,@body))))
 870
 871 (defun call-no-next-method (method-name-declaration &rest args)
 872   (destructuring-bind (name) method-name-declaration
 873     (destructuring-bind (name &rest qualifiers-and-specializers) name
 874       ;; KLUDGE: inefficient traversal, but hey.  This should only
 875       ;; happen on the slow error path anyway.
 876       (let* ((qualifiers (butlast qualifiers-and-specializers))
 877              (specializers (car (last qualifiers-and-specializers)))
 878              (method (find-method (gdefinition name) qualifiers specializers)))
 879         (apply #'no-next-method
 880                (method-generic-function method)
 881                method
 882                args)))))
 883
 884 (defstruct (method-call (:copier nil))
 885   (function #'identity :type function)
 886   call-method-args)
 887
 888 #-sb-fluid (declaim (sb-ext:freeze-type method-call))
 889
 890 (defmacro invoke-method-call1 (function args cm-args)
 891   `(let ((.function. ,function)
 892          (.args. ,args)
 893          (.cm-args. ,cm-args))
 894      (if (and .cm-args. (null (cdr .cm-args.)))
 895          (funcall .function. .args. (car .cm-args.))
 896          (apply .function. .args. .cm-args.))))
 897
 898 (defmacro invoke-method-call (method-call restp &rest required-args+rest-arg)
 899   `(invoke-method-call1 (method-call-function ,method-call)
 900                         ,(if restp
 901                              `(list* ,@required-args+rest-arg)
 902                              `(list ,@required-args+rest-arg))
 903                         (method-call-call-method-args ,method-call)))
 904
 905 (defstruct (fast-method-call (:copier nil))
 906   (function #'identity :type function)
 907   pv-cell
 908   next-method-call
 909   arg-info)
 910
 911 #-sb-fluid (declaim (sb-ext:freeze-type fast-method-call))
 912
 913 (defmacro fmc-funcall (fn pv-cell next-method-call &rest args)
 914   `(funcall ,fn ,pv-cell ,next-method-call ,@args))
 915
 916 (defmacro invoke-fast-method-call (method-call &rest required-args+rest-arg)
 917   `(fmc-funcall (fast-method-call-function ,method-call)
 918                 (fast-method-call-pv-cell ,method-call)
 919                 (fast-method-call-next-method-call ,method-call)
 920                 ,@required-args+rest-arg))
 921
 922 (defstruct (fast-instance-boundp (:copier nil))
 923   (index 0 :type fixnum))
 924
 925 #-sb-fluid (declaim (sb-ext:freeze-type fast-instance-boundp))
 926
 927 (eval-when (:compile-toplevel :load-toplevel :execute)
 928   (defvar *allow-emf-call-tracing-p* nil)
 929   (defvar *enable-emf-call-tracing-p* #-sb-show nil #+sb-show t))
 930 \f
 931 ;;;; effective method functions
 932
 933 (defvar *emf-call-trace-size* 200)
 934 (defvar *emf-call-trace* nil)
 935 (defvar *emf-call-trace-index* 0)
 936
 937 ;;; This function was in the CMU CL version of PCL (ca Debian 2.4.8)
 938 ;;; without explanation. It appears to be intended for debugging, so
 939 ;;; it might be useful someday, so I haven't deleted it.
 940 ;;; But it isn't documented and isn't used for anything now, so
 941 ;;; I've conditionalized it out of the base system. -- WHN 19991213
 942 #+sb-show
 943 (defun show-emf-call-trace ()
 944   (when *emf-call-trace*
 945     (let ((j *emf-call-trace-index*)
 946           (*enable-emf-call-tracing-p* nil))
 947       (format t "~&(The oldest entries are printed first)~%")
 948       (dotimes-fixnum (i *emf-call-trace-size*)
 949         (let ((ct (aref *emf-call-trace* j)))
 950           (when ct (print ct)))
 951         (incf j)
 952         (when (= j *emf-call-trace-size*)
 953           (setq j 0))))))
 954
 955 (defun trace-emf-call-internal (emf format args)
 956   (unless *emf-call-trace*
 957     (setq *emf-call-trace* (make-array *emf-call-trace-size*)))
 958   (setf (aref *emf-call-trace* *emf-call-trace-index*)
 959         (list* emf format args))
 960   (incf *emf-call-trace-index*)
 961   (when (= *emf-call-trace-index* *emf-call-trace-size*)
 962     (setq *emf-call-trace-index* 0)))
 963
 964 (defmacro trace-emf-call (emf format args)
 965   (when *allow-emf-call-tracing-p*
 966     `(when *enable-emf-call-tracing-p*
 967        (trace-emf-call-internal ,emf ,format ,args))))
 968
 969 (defmacro invoke-effective-method-function-fast
 970     (emf restp &rest required-args+rest-arg)
 971   `(progn
 972      (trace-emf-call ,emf ,restp (list ,@required-args+rest-arg))
 973      (invoke-fast-method-call ,emf ,@required-args+rest-arg)))
 974
 975 (defmacro invoke-effective-method-function (emf restp
 976                                                 &rest required-args+rest-arg)
 977   (unless (constantp restp)
 978     (error "The RESTP argument is not constant."))
 979   ;; FIXME: The RESTP handling here is confusing and maybe slightly
 980   ;; broken if RESTP evaluates to a non-self-evaluating form. E.g. if
 981   ;;   (INVOKE-EFFECTIVE-METHOD-FUNCTION EMF '(ERROR "gotcha") ...)
 982   ;; then TRACE-EMF-CALL-CALL-INTERNAL might die on a gotcha error.
 983   (setq restp (constant-form-value restp))
 984   `(progn
 985      (trace-emf-call ,emf ,restp (list ,@required-args+rest-arg))
 986      (cond ((typep ,emf 'fast-method-call)
 987             (invoke-fast-method-call ,emf ,@required-args+rest-arg))
 988            ;; "What," you may wonder, "do these next two clauses do?"
 989            ;; In that case, you are not a PCL implementor, for they
 990            ;; considered this to be self-documenting.:-| Or CSR, for
 991            ;; that matter, since he can also figure it out by looking
 992            ;; at it without breaking stride. For the rest of us,
 993            ;; though: From what the code is doing with .SLOTS. and
 994            ;; whatnot, evidently it's implementing SLOT-VALUEish and
 995            ;; GET-SLOT-VALUEish things. Then we can reason backwards
 996            ;; and conclude that setting EMF to a FIXNUM is an
 997            ;; optimized way to represent these slot access operations.
 998            ,@(when (and (null restp) (= 1 (length required-args+rest-arg)))
 999                `(((typep ,emf 'fixnum)
1000                   (let* ((.slots. (get-slots-or-nil
1001                                    ,(car required-args+rest-arg)))
1002                          (value (when .slots. (clos-slots-ref .slots. ,emf))))
1003                     (if (eq value +slot-unbound+)
1004                         (slot-unbound-internal ,(car required-args+rest-arg)
1005                                                ,emf)
1006                         value)))))
1007            ,@(when (and (null restp) (= 2 (length required-args+rest-arg)))
1008                `(((typep ,emf 'fixnum)
1009                   (let ((.new-value. ,(car required-args+rest-arg))
1010                         (.slots. (get-slots-or-nil
1011                                   ,(cadr required-args+rest-arg))))
1012                     (when .slots.
1013                       (setf (clos-slots-ref .slots. ,emf) .new-value.))))))
1014            ;; (In cmucl-2.4.8 there was a commented-out third ,@(WHEN
1015            ;; ...) clause here to handle SLOT-BOUNDish stuff. Since
1016            ;; there was no explanation and presumably the code is 10+
1017            ;; years stale, I simply deleted it. -- WHN)
1018            (t
1019             (etypecase ,emf
1020               (method-call
1021                (invoke-method-call ,emf ,restp ,@required-args+rest-arg))
1022               (function
1023                ,(if restp
1024                     `(apply (the function ,emf) ,@required-args+rest-arg)
1025                     `(funcall (the function ,emf)
1026                               ,@required-args+rest-arg))))))))
1027
1028 (defun invoke-emf (emf args)
1029   (trace-emf-call emf t args)
1030   (etypecase emf
1031     (fast-method-call
1032      (let* ((arg-info (fast-method-call-arg-info emf))
1033             (restp (cdr arg-info))
1034             (nreq (car arg-info)))
1035        (if restp
1036            (let* ((rest-args (nthcdr nreq args))
1037                   (req-args (ldiff args rest-args)))
1038              (apply (fast-method-call-function emf)
1039                     (fast-method-call-pv-cell emf)
1040                     (fast-method-call-next-method-call emf)
1041                     (nconc req-args (list rest-args))))
1042            (cond ((null args)
1043                   (if (eql nreq 0)
1044                       (invoke-fast-method-call emf)
1045                       (error 'simple-program-error
1046                              :format-control "invalid number of arguments: 0"
1047                              :format-arguments nil)))
1048                  ((null (cdr args))
1049                   (if (eql nreq 1)
1050                       (invoke-fast-method-call emf (car args))
1051                       (error 'simple-program-error
1052                              :format-control "invalid number of arguments: 1"
1053                              :format-arguments nil)))
1054                  ((null (cddr args))
1055                   (if (eql nreq 2)
1056                       (invoke-fast-method-call emf (car args) (cadr args))
1057                       (error 'simple-program-error
1058                              :format-control "invalid number of arguments: 2"
1059                              :format-arguments nil)))
1060                  (t
1061                   (apply (fast-method-call-function emf)
1062                          (fast-method-call-pv-cell emf)
1063                          (fast-method-call-next-method-call emf)
1064                          args))))))
1065     (method-call
1066      (apply (method-call-function emf)
1067             args
1068             (method-call-call-method-args emf)))
1069     (fixnum
1070      (cond ((null args)
1071             (error 'simple-program-error
1072                    :format-control "invalid number of arguments: 0"
1073                    :format-arguments nil))
1074            ((null (cdr args))
1075             (let* ((slots (get-slots (car args)))
1076                    (value (clos-slots-ref slots emf)))
1077               (if (eq value +slot-unbound+)
1078                   (slot-unbound-internal (car args) emf)
1079                   value)))
1080            ((null (cddr args))
1081             (setf (clos-slots-ref (get-slots (cadr args)) emf)
1082                   (car args)))
1083            (t (error 'simple-program-error
1084                      :format-control "invalid number of arguments"
1085                      :format-arguments nil))))
1086     (fast-instance-boundp
1087      (if (or (null args) (cdr args))
1088          (error 'simple-program-error
1089                 :format-control "invalid number of arguments"
1090                 :format-arguments nil)
1091          (let ((slots (get-slots (car args))))
1092            (not (eq (clos-slots-ref slots (fast-instance-boundp-index emf))
1093                     +slot-unbound+)))))
1094     (function
1095      (apply emf args))))
1096 \f
1097
1098 (defmacro fast-narrowed-emf (emf)
1099   ;; INVOKE-EFFECTIVE-METHOD-FUNCTION has code in it to dispatch on
1100   ;; the possibility that EMF might be of type FIXNUM (as an optimized
1101   ;; representation of a slot accessor). But as far as I (WHN
1102   ;; 2002-06-11) can tell, it's impossible for such a representation
1103   ;; to end up as .NEXT-METHOD-CALL. By reassuring INVOKE-E-M-F that
1104   ;; when called from this context it needn't worry about the FIXNUM
1105   ;; case, we can keep those cases from being compiled, which is good
1106   ;; both because it saves bytes and because it avoids annoying type
1107   ;; mismatch compiler warnings.
1108   ;;
1109   ;; KLUDGE: In sbcl-0.7.4.29, the compiler's type system isn't smart
1110   ;; enough about NOT and intersection types to benefit from a (NOT
1111   ;; FIXNUM) declaration here. -- WHN 2002-06-12 (FIXME: maybe it is
1112   ;; now... -- CSR, 2003-06-07)
1113   ;;
1114   ;; FIXME: Might the FUNCTION type be omittable here, leaving only
1115   ;; METHOD-CALLs? Failing that, could this be documented somehow?
1116   ;; (It'd be nice if the types involved could be understood without
1117   ;; solving the halting problem.)
1118   `(the (or function method-call fast-method-call)
1119      ,emf))
1120
1121 (defmacro fast-call-next-method-body ((args next-method-call rest-arg)
1122                                       method-name-declaration
1123                                       cnm-args)
1124   `(if ,next-method-call
1125        ,(let ((call `(invoke-effective-method-function
1126                       (fast-narrowed-emf ,next-method-call)
1127                       ,(not (null rest-arg))
1128                       ,@args
1129                       ,@(when rest-arg `(,rest-arg)))))
1130              `(if ,cnm-args
1131                   (bind-args ((,@args
1132                                ,@(when rest-arg
1133                                        `(&rest ,rest-arg)))
1134                               ,cnm-args)
1135                     ,call)
1136                   ,call))
1137        (call-no-next-method ',method-name-declaration
1138                             ,@args
1139                             ,@(when rest-arg
1140                                     `(,rest-arg)))))
1141
1142 (defmacro bind-fast-lexical-method-functions
1143     ((args rest-arg next-method-call (&key
1144                                       call-next-method-p
1145                                       setq-p
1146                                       method-name-declaration
1147                                       next-method-p-p
1148                                       closurep
1149                                       applyp))
1150      &body body
1151      &environment env)
1152   (let* ((all-params (append args (when rest-arg (list rest-arg))))
1153          (rebindings (when (or setq-p call-next-method-p)
1154                        (mapcar (lambda (x) (list x x)) all-params))))
1155     (if (not (or call-next-method-p setq-p closurep next-method-p-p applyp))
1156         `(locally
1157              ,@body)
1158         `(flet (,@(when call-next-method-p
1159                         `((call-next-method (&rest cnm-args)
1160                            (declare (muffle-conditions code-deletion-note))
1161                            ,@(if (safe-code-p env)
1162                                  `((%check-cnm-args cnm-args (list ,@args)
1163                                                     ',method-name-declaration))
1164                                  nil)
1165                            (fast-call-next-method-body (,args
1166                                                         ,next-method-call
1167                                                         ,rest-arg)
1168                                                         ,method-name-declaration
1169                                                        cnm-args))))
1170                 ,@(when next-method-p-p
1171                         `((next-method-p
1172                            ()
1173                            (not (null ,next-method-call))))))
1174            (let ,rebindings
1175              ,@(when rebindings `((declare (ignorable ,@all-params))))
1176              ,@body)))))
1177
1178 ;;; CMUCL comment (Gerd Moellmann):
1179 ;;;
1180 ;;; The standard says it's an error if CALL-NEXT-METHOD is called with
1181 ;;; arguments, and the set of methods applicable to those arguments is
1182 ;;; different from the set of methods applicable to the original
1183 ;;; method arguments.  (According to Barry Margolin, this rule was
1184 ;;; probably added to ensure that before and around methods are always
1185 ;;; run before primary methods.)
1186 ;;;
1187 ;;; This could be optimized for the case that the generic function
1188 ;;; doesn't have hairy methods, does have standard method combination,
1189 ;;; is a standard generic function, there are no methods defined on it
1190 ;;; for COMPUTE-APPLICABLE-METHODS and probably a lot more of such
1191 ;;; preconditions.  That looks hairy and is probably not worth it,
1192 ;;; because this check will never be fast.
1193 (defun %check-cnm-args (cnm-args orig-args method-name-declaration)
1194   (when cnm-args
1195     (let* ((gf (fdefinition (caar method-name-declaration)))
1196            (omethods (compute-applicable-methods gf orig-args))
1197            (nmethods (compute-applicable-methods gf cnm-args)))
1198       (unless (equal omethods nmethods)
1199         (error "~@<The set of methods ~S applicable to argument~P ~
1200                 ~{~S~^, ~} to call-next-method is different from ~
1201                 the set of methods ~S applicable to the original ~
1202                 method argument~P ~{~S~^, ~}.~@:>"
1203                nmethods (length cnm-args) cnm-args omethods
1204                (length orig-args) orig-args)))))
1205
1206 (defmacro bind-args ((lambda-list args) &body body)
1207   (let ((args-tail '.args-tail.)
1208         (key '.key.)
1209         (state 'required))
1210     (flet ((process-var (var)
1211              (if (memq var lambda-list-keywords)
1212                  (progn
1213                    (case var
1214                      (&optional       (setq state 'optional))
1215                      (&key            (setq state 'key))
1216                      (&allow-other-keys)
1217                      (&rest           (setq state 'rest))
1218                      (&aux            (setq state 'aux))
1219                      (otherwise
1220                       (error
1221                        "encountered the non-standard lambda list keyword ~S"
1222                        var)))
1223                    nil)
1224                  (case state
1225                    (required `((,var (pop ,args-tail))))
1226                    (optional (cond ((not (consp var))
1227                                     `((,var (when ,args-tail
1228                                               (pop ,args-tail)))))
1229                                    ((null (cddr var))
1230                                     `((,(car var) (if ,args-tail
1231                                                       (pop ,args-tail)
1232                                                       ,(cadr var)))))
1233                                    (t
1234                                     `((,(caddr var) ,args-tail)
1235                                       (,(car var) (if ,args-tail
1236                                                       (pop ,args-tail)
1237                                                       ,(cadr var)))))))
1238                    (rest `((,var ,args-tail)))
1239                    (key (cond ((not (consp var))
1240                                `((,var (car
1241                                         (get-key-arg-tail ,(keywordicate var)
1242                                                           ,args-tail)))))
1243                               ((null (cddr var))
1244                                (multiple-value-bind (keyword variable)
1245                                    (if (consp (car var))
1246                                        (values (caar var)
1247                                                (cadar var))
1248                                        (values (keywordicate (car var))
1249                                                (car var)))
1250                                  `((,key (get-key-arg-tail ',keyword
1251                                                            ,args-tail))
1252                                    (,variable (if ,key
1253                                                   (car ,key)
1254                                                   ,(cadr var))))))
1255                               (t
1256                                (multiple-value-bind (keyword variable)
1257                                    (if (consp (car var))
1258                                        (values (caar var)
1259                                                (cadar var))
1260                                        (values (keywordicate (car var))
1261                                                (car var)))
1262                                  `((,key (get-key-arg-tail ',keyword
1263                                                            ,args-tail))
1264                                    (,(caddr var) ,key)
1265                                    (,variable (if ,key
1266                                                   (car ,key)
1267                                                   ,(cadr var))))))))
1268                    (aux `(,var))))))
1269       (let ((bindings (mapcan #'process-var lambda-list)))
1270         `(let* ((,args-tail ,args)
1271                 ,@bindings
1272                 (.dummy0.
1273                  ,@(when (eq state 'optional)
1274                      `((unless (null ,args-tail)
1275                          (error 'simple-program-error
1276                                 :format-control "surplus arguments: ~S"
1277                                 :format-arguments (list ,args-tail)))))))
1278            (declare (ignorable ,args-tail .dummy0.))
1279            ,@body)))))
1280
1281 (defun get-key-arg-tail (keyword list)
1282   (loop for (key . tail) on list by #'cddr
1283         when (null tail) do
1284           ;; FIXME: Do we want to export this symbol? Or maybe use an
1285           ;; (ERROR 'SIMPLE-PROGRAM-ERROR) form?
1286           (sb-c::%odd-key-args-error)
1287         when (eq key keyword)
1288           return tail))
1289
1290 (defun walk-method-lambda (method-lambda required-parameters env slots calls)
1291   (let ((call-next-method-p nil)   ; flag indicating that CALL-NEXT-METHOD
1292                                    ; should be in the method definition
1293         (closurep nil)             ; flag indicating that #'CALL-NEXT-METHOD
1294                                    ; was seen in the body of a method
1295         (next-method-p-p nil)      ; flag indicating that NEXT-METHOD-P
1296                                    ; should be in the method definition
1297         (setq-p nil))
1298     (flet ((walk-function (form context env)
1299              (cond ((not (eq context :eval)) form)
1300                    ;; FIXME: Jumping to a conclusion from the way it's used
1301                    ;; above, perhaps CONTEXT should be called SITUATION
1302                    ;; (after the term used in the ANSI specification of
1303                    ;; EVAL-WHEN) and given modern ANSI keyword values
1304                    ;; like :LOAD-TOPLEVEL.
1305                    ((not (listp form)) form)
1306                    ((eq (car form) 'call-next-method)
1307                     (setq call-next-method-p t)
1308                     form)
1309                    ((eq (car form) 'next-method-p)
1310                     (setq next-method-p-p t)
1311                     form)
1312                    ((memq (car form) '(setq multiple-value-setq))
1313                     ;; FIXME: this is possibly a little strong as
1314                     ;; conditions go.  Ideally we would want to detect
1315                     ;; which, if any, of the method parameters are
1316                     ;; being set, and communicate that information to
1317                     ;; e.g. SPLIT-DECLARATIONS.  However, the brute
1318                     ;; force method doesn't really cost much; a little
1319                     ;; loss of discrimination over IGNORED variables
1320                     ;; should be all.  -- CSR, 2004-07-01
1321                     (setq setq-p t)
1322                     form)
1323                    ((and (eq (car form) 'function)
1324                          (cond ((eq (cadr form) 'call-next-method)
1325                                 (setq call-next-method-p t)
1326                                 (setq closurep t)
1327                                 form)
1328                                ((eq (cadr form) 'next-method-p)
1329                                 (setq next-method-p-p t)
1330                                 (setq closurep t)
1331                                 form)
1332                                (t nil))))
1333                    ((and (memq (car form)
1334                                '(slot-value set-slot-value slot-boundp))
1335                          (constantp (caddr form)))
1336                      (let ((parameter (can-optimize-access form
1337                                                            required-parameters
1338                                                            env)))
1339                       (let ((fun (ecase (car form)
1340                                    (slot-value #'optimize-slot-value)
1341                                    (set-slot-value #'optimize-set-slot-value)
1342                                    (slot-boundp #'optimize-slot-boundp))))
1343                         (funcall fun slots parameter form))))
1344                    ((and (eq (car form) 'apply)
1345                          (consp (cadr form))
1346                          (eq (car (cadr form)) 'function)
1347                          (generic-function-name-p (cadr (cadr form))))
1348                     (optimize-generic-function-call
1349                      form required-parameters env slots calls))
1350                    ((generic-function-name-p (car form))
1351                     (optimize-generic-function-call
1352                      form required-parameters env slots calls))
1353                    (t form))))
1354
1355       (let ((walked-lambda (walk-form method-lambda env #'walk-function)))
1356         (values walked-lambda
1357                 call-next-method-p
1358                 closurep
1359                 next-method-p-p
1360                 setq-p)))))
1361
1362 (defun generic-function-name-p (name)
1363   (and (legal-fun-name-p name)
1364        (fboundp name)
1365        (if (eq *boot-state* 'complete)
1366            (standard-generic-function-p (gdefinition name))
1367            (funcallable-instance-p (gdefinition name)))))
1368 \f
1369 (defvar *method-function-plist* (make-hash-table :test 'eq))
1370
1371 (defun method-function-plist (method-function)
1372   (gethash method-function *method-function-plist*))
1373
1374 (defun (setf method-function-plist) (val method-function)
1375   (setf (gethash method-function *method-function-plist*) val))
1376
1377 (defun method-function-get (method-function key &optional default)
1378   (getf (method-function-plist method-function) key default))
1379
1380 (defun (setf method-function-get)
1381     (val method-function key)
1382   (setf (getf (method-function-plist method-function) key) val))
1383
1384 (defun method-function-pv-table (method-function)
1385   (method-function-get method-function :pv-table))
1386
1387 (defun method-function-method (method-function)
1388   (method-function-get method-function :method))
1389
1390 (defun method-function-needs-next-methods-p (method-function)
1391   (method-function-get method-function :needs-next-methods-p t))
1392 \f
1393 (defmacro method-function-closure-generator (method-function)
1394   `(method-function-get ,method-function 'closure-generator))
1395
1396 (defun load-defmethod
1397     (class name quals specls ll initargs pv-table-symbol source-location)
1398   (setq initargs (copy-tree initargs))
1399   (let ((method-spec (or (getf initargs :method-spec)
1400                          (make-method-spec name quals specls))))
1401     (setf (getf initargs :method-spec) method-spec)
1402     (load-defmethod-internal class name quals specls
1403                              ll initargs pv-table-symbol
1404                              source-location)))
1405
1406 (defun load-defmethod-internal
1407     (method-class gf-spec qualifiers specializers lambda-list
1408                   initargs pv-table-symbol source-location)
1409   (when pv-table-symbol
1410     (setf (getf (getf initargs :plist) :pv-table-symbol)
1411           pv-table-symbol))
1412   (when (and (eq *boot-state* 'complete)
1413              (fboundp gf-spec))
1414     (let* ((gf (fdefinition gf-spec))
1415            (method (and (generic-function-p gf)
1416                         (generic-function-methods gf)
1417                         (find-method gf
1418                                      qualifiers
1419                                      (parse-specializers specializers)
1420                                      nil))))
1421       (when method
1422         (style-warn "redefining ~S~{ ~S~} ~S in DEFMETHOD"
1423                     gf-spec qualifiers specializers))))
1424   (let ((method (apply #'add-named-method
1425                        gf-spec qualifiers specializers lambda-list
1426                        :definition-source source-location
1427                        initargs)))
1428     (unless (or (eq method-class 'standard-method)
1429                 (eq (find-class method-class nil) (class-of method)))
1430       ;; FIXME: should be STYLE-WARNING?
1431       (format *error-output*
1432               "~&At the time the method with qualifiers ~:S and~%~
1433                specializers ~:S on the generic function ~S~%~
1434                was compiled, the method-class for that generic function was~%~
1435                ~S. But, the method class is now ~S, this~%~
1436                may mean that this method was compiled improperly.~%"
1437               qualifiers specializers gf-spec
1438               method-class (class-name (class-of method))))
1439     method))
1440
1441 (defun make-method-spec (gf-spec qualifiers unparsed-specializers)
1442   `(slow-method ,gf-spec ,@qualifiers ,unparsed-specializers))
1443
1444 (defun initialize-method-function (initargs &optional return-function-p method)
1445   (let* ((mf (getf initargs :function))
1446          (method-spec (getf initargs :method-spec))
1447          (plist (getf initargs :plist))
1448          (pv-table-symbol (getf plist :pv-table-symbol))
1449          (pv-table nil)
1450          (mff (getf initargs :fast-function)))
1451     (flet ((set-mf-property (p v)
1452              (when mf
1453                (setf (method-function-get mf p) v))
1454              (when mff
1455                (setf (method-function-get mff p) v))))
1456       (when method-spec
1457         (when mf
1458           (setq mf (set-fun-name mf method-spec)))
1459         (when mff
1460           (let ((name `(fast-method ,@(cdr method-spec))))
1461             (set-fun-name mff name)
1462             (unless mf
1463               (set-mf-property :name name)))))
1464       (when plist
1465         (let ((snl (getf plist :slot-name-lists))
1466               (cl (getf plist :call-list)))
1467           (when (or snl cl)
1468             (setq pv-table (intern-pv-table :slot-name-lists snl
1469                                             :call-list cl))
1470             (when pv-table (set pv-table-symbol pv-table))
1471             (set-mf-property :pv-table pv-table)))
1472         (loop (when (null plist) (return nil))
1473               (set-mf-property (pop plist) (pop plist)))
1474         (when method
1475           (set-mf-property :method method))
1476         (when return-function-p
1477           (or mf (method-function-from-fast-function mff)))))))
1478 \f
1479 (defun analyze-lambda-list (lambda-list)
1480   (flet (;; FIXME: Is this redundant with SB-C::MAKE-KEYWORD-FOR-ARG?
1481          (parse-key-arg (arg)
1482            (if (listp arg)
1483                (if (listp (car arg))
1484                    (caar arg)
1485                    (keywordicate (car arg)))
1486                (keywordicate arg))))
1487     (let ((nrequired 0)
1488           (noptional 0)
1489           (keysp nil)
1490           (restp nil)
1491           (nrest 0)
1492           (allow-other-keys-p nil)
1493           (keywords ())
1494           (keyword-parameters ())
1495           (state 'required))
1496       (dolist (x lambda-list)
1497         (if (memq x lambda-list-keywords)
1498             (case x
1499               (&optional         (setq state 'optional))
1500               (&key              (setq keysp t
1501                                        state 'key))
1502               (&allow-other-keys (setq allow-other-keys-p t))
1503               (&rest             (setq restp t
1504                                        state 'rest))
1505               (&aux           (return t))
1506               (otherwise
1507                 (error "encountered the non-standard lambda list keyword ~S"
1508                        x)))
1509             (ecase state
1510               (required  (incf nrequired))
1511               (optional  (incf noptional))
1512               (key       (push (parse-key-arg x) keywords)
1513                          (push x keyword-parameters))
1514               (rest      (incf nrest)))))
1515       (when (and restp (zerop nrest))
1516         (error "Error in lambda-list:~%~
1517                 After &REST, a DEFGENERIC lambda-list ~
1518                 must be followed by at least one variable."))
1519       (values nrequired noptional keysp restp allow-other-keys-p
1520               (reverse keywords)
1521               (reverse keyword-parameters)))))
1522
1523 (defun keyword-spec-name (x)
1524   (let ((key (if (atom x) x (car x))))
1525     (if (atom key)
1526         (keywordicate key)
1527         (car key))))
1528
1529 (defun ftype-declaration-from-lambda-list (lambda-list name)
1530   (multiple-value-bind (nrequired noptional keysp restp allow-other-keys-p
1531                                   keywords keyword-parameters)
1532       (analyze-lambda-list lambda-list)
1533     (declare (ignore keyword-parameters))
1534     (let* ((old (info :function :type name)) ;FIXME:FDOCUMENTATION instead?
1535            (old-ftype (if (fun-type-p old) old nil))
1536            (old-restp (and old-ftype (fun-type-rest old-ftype)))
1537            (old-keys (and old-ftype
1538                           (mapcar #'key-info-name
1539                                   (fun-type-keywords
1540                                    old-ftype))))
1541            (old-keysp (and old-ftype (fun-type-keyp old-ftype)))
1542            (old-allowp (and old-ftype
1543                             (fun-type-allowp old-ftype)))
1544            (keywords (union old-keys (mapcar #'keyword-spec-name keywords))))
1545       `(function ,(append (make-list nrequired :initial-element t)
1546                           (when (plusp noptional)
1547                             (append '(&optional)
1548                                     (make-list noptional :initial-element t)))
1549                           (when (or restp old-restp)
1550                             '(&rest t))
1551                           (when (or keysp old-keysp)
1552                             (append '(&key)
1553                                     (mapcar (lambda (key)
1554                                               `(,key t))
1555                                             keywords)
1556                                     (when (or allow-other-keys-p old-allowp)
1557                                       '(&allow-other-keys)))))
1558                  *))))
1559
1560 (defun defgeneric-declaration (spec lambda-list)
1561   `(ftype ,(ftype-declaration-from-lambda-list lambda-list spec) ,spec))
1562 \f
1563 ;;;; early generic function support
1564
1565 (defvar *!early-generic-functions* ())
1566
1567 (defun ensure-generic-function (fun-name
1568                                 &rest all-keys
1569                                 &key environment source-location
1570                                 &allow-other-keys)
1571   (declare (ignore environment))
1572   (let ((existing (and (fboundp fun-name)
1573                        (gdefinition fun-name))))
1574     (if (and existing
1575              (eq *boot-state* 'complete)
1576              (null (generic-function-p existing)))
1577         (generic-clobbers-function fun-name)
1578         (apply #'ensure-generic-function-using-class
1579                existing fun-name all-keys))))
1580
1581 (defun generic-clobbers-function (fun-name)
1582   (error 'simple-program-error
1583          :format-control "~S already names an ordinary function or a macro."
1584          :format-arguments (list fun-name)))
1585
1586 (defvar *sgf-wrapper*
1587   (boot-make-wrapper (early-class-size 'standard-generic-function)
1588                      'standard-generic-function))
1589
1590 (defvar *sgf-slots-init*
1591   (mapcar (lambda (canonical-slot)
1592             (if (memq (getf canonical-slot :name) '(arg-info source))
1593                 +slot-unbound+
1594                 (let ((initfunction (getf canonical-slot :initfunction)))
1595                   (if initfunction
1596                       (funcall initfunction)
1597                       +slot-unbound+))))
1598           (early-collect-inheritance 'standard-generic-function)))
1599
1600 (defvar *sgf-method-class-index*
1601   (!bootstrap-slot-index 'standard-generic-function 'method-class))
1602
1603 (defun early-gf-p (x)
1604   (and (fsc-instance-p x)
1605        (eq (clos-slots-ref (get-slots x) *sgf-method-class-index*)
1606            +slot-unbound+)))
1607
1608 (defvar *sgf-methods-index*
1609   (!bootstrap-slot-index 'standard-generic-function 'methods))
1610
1611 (defmacro early-gf-methods (gf)
1612   `(clos-slots-ref (get-slots ,gf) *sgf-methods-index*))
1613
1614 (defun safe-generic-function-methods (generic-function)
1615   (if (eq (class-of generic-function) *the-class-standard-generic-function*)
1616       (clos-slots-ref (get-slots generic-function) *sgf-methods-index*)
1617       (generic-function-methods generic-function)))
1618
1619 (defvar *sgf-arg-info-index*
1620   (!bootstrap-slot-index 'standard-generic-function 'arg-info))
1621
1622 (defmacro early-gf-arg-info (gf)
1623   `(clos-slots-ref (get-slots ,gf) *sgf-arg-info-index*))
1624
1625 (defvar *sgf-dfun-state-index*
1626   (!bootstrap-slot-index 'standard-generic-function 'dfun-state))
1627
1628 (defstruct (arg-info
1629             (:conc-name nil)
1630             (:constructor make-arg-info ())
1631             (:copier nil))
1632   (arg-info-lambda-list :no-lambda-list)
1633   arg-info-precedence
1634   arg-info-metatypes
1635   arg-info-number-optional
1636   arg-info-key/rest-p
1637   arg-info-keys   ;nil        no &KEY or &REST allowed
1638                   ;(k1 k2 ..) Each method must accept these &KEY arguments.
1639                   ;T          must have &KEY or &REST
1640
1641   gf-info-simple-accessor-type ; nil, reader, writer, boundp
1642   (gf-precompute-dfun-and-emf-p nil) ; set by set-arg-info
1643
1644   gf-info-static-c-a-m-emf
1645   (gf-info-c-a-m-emf-std-p t)
1646   gf-info-fast-mf-p)
1647
1648 #-sb-fluid (declaim (sb-ext:freeze-type arg-info))
1649
1650 (defun arg-info-valid-p (arg-info)
1651   (not (null (arg-info-number-optional arg-info))))
1652
1653 (defun arg-info-applyp (arg-info)
1654   (or (plusp (arg-info-number-optional arg-info))
1655       (arg-info-key/rest-p arg-info)))
1656
1657 (defun arg-info-number-required (arg-info)
1658   (length (arg-info-metatypes arg-info)))
1659
1660 (defun arg-info-nkeys (arg-info)
1661   (count-if (lambda (x) (neq x t)) (arg-info-metatypes arg-info)))
1662
1663 (defun create-gf-lambda-list (lambda-list)
1664   ;;; Create a gf lambda list from a method lambda list
1665   (loop for x in lambda-list
1666         collect (if (consp x) (list (car x)) x)
1667         if (eq x '&key) do (loop-finish)))
1668
1669 (defun set-arg-info (gf &key new-method (lambda-list nil lambda-list-p)
1670                         argument-precedence-order)
1671   (let* ((arg-info (if (eq *boot-state* 'complete)
1672                        (gf-arg-info gf)
1673                        (early-gf-arg-info gf)))
1674          (methods (if (eq *boot-state* 'complete)
1675                       (generic-function-methods gf)
1676                       (early-gf-methods gf)))
1677          (was-valid-p (integerp (arg-info-number-optional arg-info)))
1678          (first-p (and new-method (null (cdr methods)))))
1679     (when (and (not lambda-list-p) methods)
1680       (setq lambda-list (gf-lambda-list gf)))
1681     (when (or lambda-list-p
1682               (and first-p
1683                    (eq (arg-info-lambda-list arg-info) :no-lambda-list)))
1684       (multiple-value-bind (nreq nopt keysp restp allow-other-keys-p keywords)
1685           (analyze-lambda-list lambda-list)
1686         (when (and methods (not first-p))
1687           (let ((gf-nreq (arg-info-number-required arg-info))
1688                 (gf-nopt (arg-info-number-optional arg-info))
1689                 (gf-key/rest-p (arg-info-key/rest-p arg-info)))
1690             (unless (and (= nreq gf-nreq)
1691                          (= nopt gf-nopt)
1692                          (eq (or keysp restp) gf-key/rest-p))
1693               (error "The lambda-list ~S is incompatible with ~
1694                      existing methods of ~S."
1695                      lambda-list gf))))
1696         (setf (arg-info-lambda-list arg-info)
1697               (if lambda-list-p
1698                   lambda-list
1699                    (create-gf-lambda-list lambda-list)))
1700         (when (or lambda-list-p argument-precedence-order
1701                   (null (arg-info-precedence arg-info)))
1702           (setf (arg-info-precedence arg-info)
1703                 (compute-precedence lambda-list nreq argument-precedence-order)))
1704         (setf (arg-info-metatypes arg-info) (make-list nreq))
1705         (setf (arg-info-number-optional arg-info) nopt)
1706         (setf (arg-info-key/rest-p arg-info) (not (null (or keysp restp))))
1707         (setf (arg-info-keys arg-info)
1708               (if lambda-list-p
1709                   (if allow-other-keys-p t keywords)
1710                   (arg-info-key/rest-p arg-info)))))
1711     (when new-method
1712       (check-method-arg-info gf arg-info new-method))
1713     (set-arg-info1 gf arg-info new-method methods was-valid-p first-p)
1714     arg-info))
1715
1716 (defun check-method-arg-info (gf arg-info method)
1717   (multiple-value-bind (nreq nopt keysp restp allow-other-keys-p keywords)
1718       (analyze-lambda-list (if (consp method)
1719                                (early-method-lambda-list method)
1720                                (method-lambda-list method)))
1721     (flet ((lose (string &rest args)
1722              (error 'simple-program-error
1723                     :format-control "~@<attempt to add the method~2I~_~S~I~_~
1724                                      to the generic function~2I~_~S;~I~_~
1725                                      but ~?~:>"
1726                     :format-arguments (list method gf string args)))
1727            (comparison-description (x y)
1728              (if (> x y) "more" "fewer")))
1729       (let ((gf-nreq (arg-info-number-required arg-info))
1730             (gf-nopt (arg-info-number-optional arg-info))
1731             (gf-key/rest-p (arg-info-key/rest-p arg-info))
1732             (gf-keywords (arg-info-keys arg-info)))
1733         (unless (= nreq gf-nreq)
1734           (lose
1735            "the method has ~A required arguments than the generic function."
1736            (comparison-description nreq gf-nreq)))
1737         (unless (= nopt gf-nopt)
1738           (lose
1739            "the method has ~A optional arguments than the generic function."
1740            (comparison-description nopt gf-nopt)))
1741         (unless (eq (or keysp restp) gf-key/rest-p)
1742           (lose
1743            "the method and generic function differ in whether they accept~_~
1744             &REST or &KEY arguments."))
1745         (when (consp gf-keywords)
1746           (unless (or (and restp (not keysp))
1747                       allow-other-keys-p
1748                       (every (lambda (k) (memq k keywords)) gf-keywords))
1749             (lose "the method does not accept each of the &KEY arguments~2I~_~
1750                    ~S."
1751                   gf-keywords)))))))
1752
1753 (defvar *sm-specializers-index*
1754   (!bootstrap-slot-index 'standard-method 'specializers))
1755 (defvar *sm-fast-function-index*
1756   (!bootstrap-slot-index 'standard-method 'fast-function))
1757 (defvar *sm-%function-index*
1758   (!bootstrap-slot-index 'standard-method '%function))
1759 (defvar *sm-plist-index*
1760   (!bootstrap-slot-index 'standard-method 'plist))
1761
1762 ;;; FIXME: we don't actually need this; we could test for the exact
1763 ;;; class and deal with it as appropriate.  In fact we probably don't
1764 ;;; need it anyway because we only use this for METHOD-SPECIALIZERS on
1765 ;;; the standard reader method for METHOD-SPECIALIZERS.  Probably.
1766 (dolist (s '(specializers fast-function %function plist))
1767   (aver (= (symbol-value (intern (format nil "*SM-~A-INDEX*" s)))
1768            (!bootstrap-slot-index 'standard-reader-method s)
1769            (!bootstrap-slot-index 'standard-writer-method s)
1770            (!bootstrap-slot-index 'standard-boundp-method s))))
1771
1772 (defun safe-method-specializers (method)
1773   (let ((standard-method-classes
1774          (list *the-class-standard-method*
1775                *the-class-standard-reader-method*
1776                *the-class-standard-writer-method*
1777                *the-class-standard-boundp-method*))
1778         (class (class-of method)))
1779     (if (member class standard-method-classes)
1780         (clos-slots-ref (get-slots method) *sm-specializers-index*)
1781         (method-specializers method))))
1782 (defun safe-method-fast-function (method)
1783   (let ((standard-method-classes
1784          (list *the-class-standard-method*
1785                *the-class-standard-reader-method*
1786                *the-class-standard-writer-method*
1787                *the-class-standard-boundp-method*))
1788         (class (class-of method)))
1789     (if (member class standard-method-classes)
1790         (clos-slots-ref (get-slots method) *sm-fast-function-index*)
1791         (method-fast-function method))))
1792 (defun safe-method-function (method)
1793   (let ((standard-method-classes
1794          (list *the-class-standard-method*
1795                *the-class-standard-reader-method*
1796                *the-class-standard-writer-method*
1797                *the-class-standard-boundp-method*))
1798         (class (class-of method)))
1799     (if (member class standard-method-classes)
1800         (clos-slots-ref (get-slots method) *sm-%function-index*)
1801         (method-function method))))
1802 (defun safe-method-qualifiers (method)
1803   (let ((standard-method-classes
1804          (list *the-class-standard-method*
1805                *the-class-standard-reader-method*
1806                *the-class-standard-writer-method*
1807                *the-class-standard-boundp-method*))
1808         (class (class-of method)))
1809     (if (member class standard-method-classes)
1810         (let ((plist (clos-slots-ref (get-slots method) *sm-plist-index*)))
1811           (getf plist 'qualifiers))
1812         (method-qualifiers method))))
1813
1814 (defun set-arg-info1 (gf arg-info new-method methods was-valid-p first-p)
1815   (let* ((existing-p (and methods (cdr methods) new-method))
1816          (nreq (length (arg-info-metatypes arg-info)))
1817          (metatypes (if existing-p
1818                         (arg-info-metatypes arg-info)
1819                         (make-list nreq)))
1820          (type (if existing-p
1821                    (gf-info-simple-accessor-type arg-info)
1822                    nil)))
1823     (when (arg-info-valid-p arg-info)
1824       (dolist (method (if new-method (list new-method) methods))
1825         (let* ((specializers (if (or (eq *boot-state* 'complete)
1826                                      (not (consp method)))
1827                                  (safe-method-specializers method)
1828                                  (early-method-specializers method t)))
1829                (class (if (or (eq *boot-state* 'complete) (not (consp method)))
1830                           (class-of method)
1831                           (early-method-class method)))
1832                (new-type
1833                 (when (and class
1834                            (or (not (eq *boot-state* 'complete))
1835                                (eq (generic-function-method-combination gf)
1836                                    *standard-method-combination*)))
1837                   (cond ((or (eq class *the-class-standard-reader-method*)
1838                              (eq class *the-class-global-reader-method*))
1839                          'reader)
1840                         ((or (eq class *the-class-standard-writer-method*)
1841                              (eq class *the-class-global-writer-method*))
1842                          'writer)
1843                         ((or (eq class *the-class-standard-boundp-method*)
1844                              (eq class *the-class-global-boundp-method*))
1845                          'boundp)))))
1846           (setq metatypes (mapcar #'raise-metatype metatypes specializers))
1847           (setq type (cond ((null type) new-type)
1848                            ((eq type new-type) type)
1849                            (t nil)))))
1850       (setf (arg-info-metatypes arg-info) metatypes)
1851       (setf (gf-info-simple-accessor-type arg-info) type)))
1852   (when (or (not was-valid-p) first-p)
1853     (multiple-value-bind (c-a-m-emf std-p)
1854         (if (early-gf-p gf)
1855             (values t t)
1856             (compute-applicable-methods-emf gf))
1857       (setf (gf-info-static-c-a-m-emf arg-info) c-a-m-emf)
1858       (setf (gf-info-c-a-m-emf-std-p arg-info) std-p)
1859       (unless (gf-info-c-a-m-emf-std-p arg-info)
1860         (setf (gf-info-simple-accessor-type arg-info) t))))
1861   (unless was-valid-p
1862     (let ((name (if (eq *boot-state* 'complete)
1863                     (generic-function-name gf)
1864                     (!early-gf-name gf))))
1865       (setf (gf-precompute-dfun-and-emf-p arg-info)
1866             (cond
1867               ((and (consp name)
1868                     (member (car name)
1869                             *internal-pcl-generalized-fun-name-symbols*))
1870                 nil)
1871               (t (let* ((symbol (fun-name-block-name name))
1872                         (package (symbol-package symbol)))
1873                    (and (or (eq package *pcl-package*)
1874                             (memq package (package-use-list *pcl-package*)))
1875                         ;; FIXME: this test will eventually be
1876                         ;; superseded by the *internal-pcl...* test,
1877                         ;; above.  While we are in a process of
1878                         ;; transition, however, it should probably
1879                         ;; remain.
1880                         (not (find #\Space (symbol-name symbol))))))))))
1881   (setf (gf-info-fast-mf-p arg-info)
1882         (or (not (eq *boot-state* 'complete))
1883             (let* ((method-class (generic-function-method-class gf))
1884                    (methods (compute-applicable-methods
1885                              #'make-method-lambda
1886                              (list gf (class-prototype method-class)
1887                                    '(lambda) nil))))
1888               (and methods (null (cdr methods))
1889                    (let ((specls (method-specializers (car methods))))
1890                      (and (classp (car specls))
1891                           (eq 'standard-generic-function
1892                               (class-name (car specls)))
1893                           (classp (cadr specls))
1894                           (eq 'standard-method
1895                               (class-name (cadr specls)))))))))
1896   arg-info)
1897
1898 ;;; This is the early definition of ENSURE-GENERIC-FUNCTION-USING-CLASS.
1899 ;;;
1900 ;;; The STATIC-SLOTS field of the funcallable instances used as early
1901 ;;; generic functions is used to store the early methods and early
1902 ;;; discriminator code for the early generic function. The static
1903 ;;; slots field of the fins contains a list whose:
1904 ;;;    CAR    -   a list of the early methods on this early gf
1905 ;;;    CADR   -   the early discriminator code for this method
1906 (defun ensure-generic-function-using-class (existing spec &rest keys
1907                                             &key (lambda-list nil
1908                                                               lambda-list-p)
1909                                             argument-precedence-order
1910                                             source-location
1911                                             &allow-other-keys)
1912   (declare (ignore keys))
1913   (cond ((and existing (early-gf-p existing))
1914          (when lambda-list-p
1915            (set-arg-info existing :lambda-list lambda-list))
1916          existing)
1917         ((assoc spec *!generic-function-fixups* :test #'equal)
1918          (if existing
1919              (make-early-gf spec lambda-list lambda-list-p existing
1920                             argument-precedence-order source-location)
1921              (error "The function ~S is not already defined." spec)))
1922         (existing
1923          (error "~S should be on the list ~S."
1924                 spec
1925                 '*!generic-function-fixups*))
1926         (t
1927          (pushnew spec *!early-generic-functions* :test #'equal)
1928          (make-early-gf spec lambda-list lambda-list-p nil
1929                         argument-precedence-order source-location))))
1930
1931 (defun make-early-gf (spec &optional lambda-list lambda-list-p
1932                       function argument-precedence-order source-location)
1933   (let ((fin (allocate-standard-funcallable-instance
1934               *sgf-wrapper* *sgf-slots-init*)))
1935     (set-funcallable-instance-function
1936      fin
1937      (or function
1938          (if (eq spec 'print-object)
1939              #'(lambda (instance stream)
1940                  (print-unreadable-object (instance stream :identity t)
1941                    (format stream "std-instance")))
1942              #'(lambda (&rest args)
1943                  (declare (ignore args))
1944                  (error "The function of the funcallable-instance ~S~
1945                          has not been set." fin)))))
1946     (setf (gdefinition spec) fin)
1947     (!bootstrap-set-slot 'standard-generic-function fin 'name spec)
1948     (!bootstrap-set-slot 'standard-generic-function
1949                          fin
1950                          'source
1951                          source-location)
1952     (set-fun-name fin spec)
1953     (let ((arg-info (make-arg-info)))
1954       (setf (early-gf-arg-info fin) arg-info)
1955       (when lambda-list-p
1956         (proclaim (defgeneric-declaration spec lambda-list))
1957         (if argument-precedence-order
1958             (set-arg-info fin
1959                           :lambda-list lambda-list
1960                           :argument-precedence-order argument-precedence-order)
1961             (set-arg-info fin :lambda-list lambda-list))))
1962     fin))
1963
1964 (defun safe-gf-dfun-state (generic-function)
1965   (if (eq (class-of generic-function) *the-class-standard-generic-function*)
1966       (clos-slots-ref (get-slots generic-function) *sgf-dfun-state-index*)
1967       (gf-dfun-state generic-function)))
1968 (defun (setf safe-gf-dfun-state) (new-value generic-function)
1969   (if (eq (class-of generic-function) *the-class-standard-generic-function*)
1970       (setf (clos-slots-ref (get-slots generic-function)
1971                             *sgf-dfun-state-index*)
1972             new-value)
1973       (setf (gf-dfun-state generic-function) new-value)))
1974
1975 (defun set-dfun (gf &optional dfun cache info)
1976   (when cache
1977     (setf (cache-owner cache) gf))
1978   (let ((new-state (if (and dfun (or cache info))
1979                        (list* dfun cache info)
1980                        dfun)))
1981     (if (eq *boot-state* 'complete)
1982         (setf (safe-gf-dfun-state gf) new-state)
1983         (setf (clos-slots-ref (get-slots gf) *sgf-dfun-state-index*)
1984               new-state)))
1985   dfun)
1986
1987 (defun gf-dfun-cache (gf)
1988   (let ((state (if (eq *boot-state* 'complete)
1989                    (safe-gf-dfun-state gf)
1990                    (clos-slots-ref (get-slots gf) *sgf-dfun-state-index*))))
1991     (typecase state
1992       (function nil)
1993       (cons (cadr state)))))
1994
1995 (defun gf-dfun-info (gf)
1996   (let ((state (if (eq *boot-state* 'complete)
1997                    (safe-gf-dfun-state gf)
1998                    (clos-slots-ref (get-slots gf) *sgf-dfun-state-index*))))
1999     (typecase state
2000       (function nil)
2001       (cons (cddr state)))))
2002
2003 (defvar *sgf-name-index*
2004   (!bootstrap-slot-index 'standard-generic-function 'name))
2005
2006 (defun !early-gf-name (gf)
2007   (clos-slots-ref (get-slots gf) *sgf-name-index*))
2008
2009 (defun gf-lambda-list (gf)
2010   (let ((arg-info (if (eq *boot-state* 'complete)
2011                       (gf-arg-info gf)
2012                       (early-gf-arg-info gf))))
2013     (if (eq :no-lambda-list (arg-info-lambda-list arg-info))
2014         (let ((methods (if (eq *boot-state* 'complete)
2015                            (generic-function-methods gf)
2016                            (early-gf-methods gf))))
2017           (if (null methods)
2018               (progn
2019                 (warn "no way to determine the lambda list for ~S" gf)
2020                 nil)
2021               (let* ((method (car (last methods)))
2022                      (ll (if (consp method)
2023                              (early-method-lambda-list method)
2024                              (method-lambda-list method))))
2025                 (create-gf-lambda-list ll))))
2026         (arg-info-lambda-list arg-info))))
2027
2028 (defmacro real-ensure-gf-internal (gf-class all-keys env)
2029   `(progn
2030      (cond ((symbolp ,gf-class)
2031             (setq ,gf-class (find-class ,gf-class t ,env)))
2032            ((classp ,gf-class))
2033            (t
2034             (error "The :GENERIC-FUNCTION-CLASS argument (~S) was neither a~%~
2035                     class nor a symbol that names a class."
2036                    ,gf-class)))
2037      (unless (class-finalized-p ,gf-class)
2038        (if (class-has-a-forward-referenced-superclass-p ,gf-class)
2039            ;; FIXME: reference MOP documentation -- this is an
2040            ;; additional requirement on our users
2041            (error "The generic function class ~S is not finalizeable" ,gf-class)
2042            (finalize-inheritance ,gf-class)))
2043      (remf ,all-keys :generic-function-class)
2044      (remf ,all-keys :environment)
2045      (let ((combin (getf ,all-keys :method-combination '.shes-not-there.)))
2046        (unless (eq combin '.shes-not-there.)
2047          (setf (getf ,all-keys :method-combination)
2048                (find-method-combination (class-prototype ,gf-class)
2049                                         (car combin)
2050                                         (cdr combin)))))
2051     (let ((method-class (getf ,all-keys :method-class '.shes-not-there.)))
2052       (unless (eq method-class '.shes-not-there.)
2053         (setf (getf ,all-keys :method-class)
2054               (cond ((classp method-class)
2055                      method-class)
2056                     (t (find-class method-class t ,env))))))))
2057
2058 (defun real-ensure-gf-using-class--generic-function
2059        (existing
2060         fun-name
2061         &rest all-keys
2062         &key environment (lambda-list nil lambda-list-p)
2063              (generic-function-class 'standard-generic-function gf-class-p)
2064         &allow-other-keys)
2065   (real-ensure-gf-internal generic-function-class all-keys environment)
2066   (unless (or (null gf-class-p)
2067               (eq (class-of existing) generic-function-class))
2068     (change-class existing generic-function-class))
2069   (prog1
2070       (apply #'reinitialize-instance existing all-keys)
2071     (when lambda-list-p
2072       (proclaim (defgeneric-declaration fun-name lambda-list)))))
2073
2074 (defun real-ensure-gf-using-class--null
2075        (existing
2076         fun-name
2077         &rest all-keys
2078         &key environment (lambda-list nil lambda-list-p)
2079              (generic-function-class 'standard-generic-function)
2080         &allow-other-keys)
2081   (declare (ignore existing))
2082   (real-ensure-gf-internal generic-function-class all-keys environment)
2083   (prog1
2084       (setf (gdefinition fun-name)
2085             (apply #'make-instance generic-function-class
2086                    :name fun-name all-keys))
2087     (when lambda-list-p
2088       (proclaim (defgeneric-declaration fun-name lambda-list)))))
2089 \f
2090 (defun safe-gf-arg-info (generic-function)
2091   (if (eq (class-of generic-function) *the-class-standard-generic-function*)
2092       (clos-slots-ref (fsc-instance-slots generic-function)
2093                       *sgf-arg-info-index*)
2094       (gf-arg-info generic-function)))
2095
2096 ;;; FIXME: this function took on a slightly greater role than it
2097 ;;; previously had around 2005-11-02, when CSR fixed the bug whereby
2098 ;;; having more than one subclass of standard-generic-function caused
2099 ;;; the whole system to die horribly through a metacircle in
2100 ;;; GF-ARG-INFO.  The fix is to be slightly more disciplined about
2101 ;;; calling accessor methods -- we call GET-GENERIC-FUN-INFO when
2102 ;;; computing discriminating functions, so we need to be careful about
2103 ;;; having a base case for the recursion, and we provide that with the
2104 ;;; STANDARD-GENERIC-FUNCTION case below.  However, we are not (yet)
2105 ;;; as disciplined as CLISP's CLOS/MOP, and it would be nice to get to
2106 ;;; that stage, where all potentially dangerous cases are enumerated
2107 ;;; and stopped.  -- CSR, 2005-11-02.
2108 (defun get-generic-fun-info (gf)
2109   ;; values   nreq applyp metatypes nkeys arg-info
2110   (multiple-value-bind (applyp metatypes arg-info)
2111       (let* ((arg-info (if (early-gf-p gf)
2112                            (early-gf-arg-info gf)
2113                            (safe-gf-arg-info gf)))
2114              (metatypes (arg-info-metatypes arg-info)))
2115         (values (arg-info-applyp arg-info)
2116                 metatypes
2117                 arg-info))
2118     (values (length metatypes) applyp metatypes
2119             (count-if (lambda (x) (neq x t)) metatypes)
2120             arg-info)))
2121
2122 (defun early-make-a-method (class qualifiers arglist specializers initargs doc
2123                             &key slot-name object-class method-class-function)
2124   (initialize-method-function initargs)
2125   (let ((parsed ())
2126         (unparsed ()))
2127     ;; Figure out whether we got class objects or class names as the
2128     ;; specializers and set parsed and unparsed appropriately. If we
2129     ;; got class objects, then we can compute unparsed, but if we got
2130     ;; class names we don't try to compute parsed.
2131     ;;
2132     ;; Note that the use of not symbolp in this call to every should be
2133     ;; read as 'classp' we can't use classp itself because it doesn't
2134     ;; exist yet.
2135     (if (every (lambda (s) (not (symbolp s))) specializers)
2136         (setq parsed specializers
2137               unparsed (mapcar (lambda (s)
2138                                  (if (eq s t) t (class-name s)))
2139                                specializers))
2140         (setq unparsed specializers
2141               parsed ()))
2142     (list :early-method           ;This is an early method dammit!
2143
2144           (getf initargs :function)
2145           (getf initargs :fast-function)
2146
2147           parsed                  ;The parsed specializers. This is used
2148                                   ;by early-method-specializers to cache
2149                                   ;the parse. Note that this only comes
2150                                   ;into play when there is more than one
2151                                   ;early method on an early gf.
2152
2153           (append
2154            (list class        ;A list to which real-make-a-method
2155                  qualifiers      ;can be applied to make a real method
2156                  arglist    ;corresponding to this early one.
2157                  unparsed
2158                  initargs
2159                  doc)
2160            (when slot-name
2161              (list :slot-name slot-name :object-class object-class
2162                    :method-class-function method-class-function))))))
2163
2164 (defun real-make-a-method
2165        (class qualifiers lambda-list specializers initargs doc
2166         &rest args &key slot-name object-class method-class-function)
2167   (setq specializers (parse-specializers specializers))
2168   (if method-class-function
2169       (let* ((object-class (if (classp object-class) object-class
2170                                (find-class object-class)))
2171              (slots (class-direct-slots object-class))
2172              (slot-definition (find slot-name slots
2173                                     :key #'slot-definition-name)))
2174         (aver slot-name)
2175         (aver slot-definition)
2176         (let ((initargs (list* :qualifiers qualifiers :lambda-list lambda-list
2177                                :specializers specializers :documentation doc
2178                                :slot-definition slot-definition
2179                                :slot-name slot-name initargs)))
2180           (apply #'make-instance
2181                  (apply method-class-function object-class slot-definition
2182                         initargs)
2183                  initargs)))
2184       (apply #'make-instance class :qualifiers qualifiers
2185              :lambda-list lambda-list :specializers specializers
2186              :documentation doc (append args initargs))))
2187
2188 (defun early-method-function (early-method)
2189   (values (cadr early-method) (caddr early-method)))
2190
2191 (defun early-method-class (early-method)
2192   (find-class (car (fifth early-method))))
2193
2194 (defun early-method-standard-accessor-p (early-method)
2195   (let ((class (first (fifth early-method))))
2196     (or (eq class 'standard-reader-method)
2197         (eq class 'standard-writer-method)
2198         (eq class 'standard-boundp-method))))
2199
2200 (defun early-method-standard-accessor-slot-name (early-method)
2201   (eighth (fifth early-method)))
2202
2203 ;;; Fetch the specializers of an early method. This is basically just
2204 ;;; a simple accessor except that when the second argument is t, this
2205 ;;; converts the specializers from symbols into class objects. The
2206 ;;; class objects are cached in the early method, this makes
2207 ;;; bootstrapping faster because the class objects only have to be
2208 ;;; computed once.
2209 ;;;
2210 ;;; NOTE:
2211 ;;;  The second argument should only be passed as T by
2212 ;;;  early-lookup-method. This is to implement the rule that only when
2213 ;;;  there is more than one early method on a generic function is the
2214 ;;;  conversion from class names to class objects done. This
2215 ;;;  corresponds to the fact that we are only allowed to have one
2216 ;;;  method on any generic function up until the time classes exist.
2217 (defun early-method-specializers (early-method &optional objectsp)
2218   (if (and (listp early-method)
2219            (eq (car early-method) :early-method))
2220       (cond ((eq objectsp t)
2221              (or (fourth early-method)
2222                  (setf (fourth early-method)
2223                        (mapcar #'find-class (cadddr (fifth early-method))))))
2224             (t
2225              (fourth (fifth early-method))))
2226       (error "~S is not an early-method." early-method)))
2227
2228 (defun early-method-qualifiers (early-method)
2229   (second (fifth early-method)))
2230
2231 (defun early-method-lambda-list (early-method)
2232   (third (fifth early-method)))
2233
2234 (defun early-add-named-method (generic-function-name
2235                                qualifiers
2236                                specializers
2237                                arglist
2238                                &rest initargs)
2239   (let* ((gf (ensure-generic-function generic-function-name))
2240          (existing
2241            (dolist (m (early-gf-methods gf))
2242              (when (and (equal (early-method-specializers m) specializers)
2243                         (equal (early-method-qualifiers m) qualifiers))
2244                (return m))))
2245          (new (make-a-method 'standard-method
2246                              qualifiers
2247                              arglist
2248                              specializers
2249                              initargs
2250                              ())))
2251     (when existing (remove-method gf existing))
2252     (add-method gf new)))
2253
2254 ;;; This is the early version of ADD-METHOD. Later this will become a
2255 ;;; generic function. See !FIX-EARLY-GENERIC-FUNCTIONS which has
2256 ;;; special knowledge about ADD-METHOD.
2257 (defun add-method (generic-function method)
2258   (when (not (fsc-instance-p generic-function))
2259     (error "Early ADD-METHOD didn't get a funcallable instance."))
2260   (when (not (and (listp method) (eq (car method) :early-method)))
2261     (error "Early ADD-METHOD didn't get an early method."))
2262   (push method (early-gf-methods generic-function))
2263   (set-arg-info generic-function :new-method method)
2264   (unless (assoc (!early-gf-name generic-function)
2265                  *!generic-function-fixups*
2266                  :test #'equal)
2267     (update-dfun generic-function)))
2268
2269 ;;; This is the early version of REMOVE-METHOD. See comments on
2270 ;;; the early version of ADD-METHOD.
2271 (defun remove-method (generic-function method)
2272   (when (not (fsc-instance-p generic-function))
2273     (error "An early remove-method didn't get a funcallable instance."))
2274   (when (not (and (listp method) (eq (car method) :early-method)))
2275     (error "An early remove-method didn't get an early method."))
2276   (setf (early-gf-methods generic-function)
2277         (remove method (early-gf-methods generic-function)))
2278   (set-arg-info generic-function)
2279   (unless (assoc (!early-gf-name generic-function)
2280                  *!generic-function-fixups*
2281                  :test #'equal)
2282     (update-dfun generic-function)))
2283
2284 ;;; This is the early version of GET-METHOD. See comments on the early
2285 ;;; version of ADD-METHOD.
2286 (defun get-method (generic-function qualifiers specializers
2287                                     &optional (errorp t))
2288   (if (early-gf-p generic-function)
2289       (or (dolist (m (early-gf-methods generic-function))
2290             (when (and (or (equal (early-method-specializers m nil)
2291                                   specializers)
2292                            (equal (early-method-specializers m t)
2293                                   specializers))
2294                        (equal (early-method-qualifiers m) qualifiers))
2295               (return m)))
2296           (if errorp
2297               (error "can't get early method")
2298               nil))
2299       (real-get-method generic-function qualifiers specializers errorp)))
2300
2301 (defun !fix-early-generic-functions ()
2302   (let ((accessors nil))
2303     ;; Rearrange *!EARLY-GENERIC-FUNCTIONS* to speed up
2304     ;; FIX-EARLY-GENERIC-FUNCTIONS.
2305     (dolist (early-gf-spec *!early-generic-functions*)
2306       (when (every #'early-method-standard-accessor-p
2307                    (early-gf-methods (gdefinition early-gf-spec)))
2308         (push early-gf-spec accessors)))
2309     (dolist (spec (nconc accessors
2310                          '(accessor-method-slot-name
2311                            generic-function-methods
2312                            method-specializers
2313                            specializerp
2314                            specializer-type
2315                            specializer-class
2316                            slot-definition-location
2317                            slot-definition-name
2318                            class-slots
2319                            gf-arg-info
2320                            class-precedence-list
2321                            slot-boundp-using-class
2322                            (setf slot-value-using-class)
2323                            slot-value-using-class
2324                            structure-class-p
2325                            standard-class-p
2326                            funcallable-standard-class-p
2327                            specializerp)))
2328       (/show spec)
2329       (setq *!early-generic-functions*
2330             (cons spec
2331                   (delete spec *!early-generic-functions* :test #'equal))))
2332
2333     (dolist (early-gf-spec *!early-generic-functions*)
2334       (/show early-gf-spec)
2335       (let* ((gf (gdefinition early-gf-spec))
2336              (methods (mapcar (lambda (early-method)
2337                                 (let ((args (copy-list (fifth
2338                                                         early-method))))
2339                                   (setf (fourth args)
2340                                         (early-method-specializers
2341                                          early-method t))
2342                                   (apply #'real-make-a-method args)))
2343                               (early-gf-methods gf))))
2344         (setf (generic-function-method-class gf) *the-class-standard-method*)
2345         (setf (generic-function-method-combination gf)
2346               *standard-method-combination*)
2347         (set-methods gf methods)))
2348
2349     (dolist (fn *!early-functions*)
2350       (/show fn)
2351       (setf (gdefinition (car fn)) (fdefinition (caddr fn))))
2352
2353     (dolist (fixup *!generic-function-fixups*)
2354       (/show fixup)
2355       (let* ((fspec (car fixup))
2356              (gf (gdefinition fspec))
2357              (methods (mapcar (lambda (method)
2358                                 (let* ((lambda-list (first method))
2359                                        (specializers (second method))
2360                                        (method-fn-name (third method))
2361                                        (fn-name (or method-fn-name fspec))
2362                                        (fn (fdefinition fn-name))
2363                                        (initargs
2364                                         (list :function
2365                                               (set-fun-name
2366                                                (lambda (args next-methods)
2367                                                  (declare (ignore
2368                                                            next-methods))
2369                                                  (apply fn args))
2370                                                `(call ,fn-name)))))
2371                                   (declare (type function fn))
2372                                   (make-a-method 'standard-method
2373                                                  ()
2374                                                  lambda-list
2375                                                  specializers
2376                                                  initargs
2377                                                  nil)))
2378                               (cdr fixup))))
2379         (setf (generic-function-method-class gf) *the-class-standard-method*)
2380         (setf (generic-function-method-combination gf)
2381               *standard-method-combination*)
2382         (set-methods gf methods))))
2383   (/show "leaving !FIX-EARLY-GENERIC-FUNCTIONS"))
2384 \f
2385 ;;; PARSE-DEFMETHOD is used by DEFMETHOD to parse the &REST argument
2386 ;;; into the 'real' arguments. This is where the syntax of DEFMETHOD
2387 ;;; is really implemented.
2388 (defun parse-defmethod (cdr-of-form)
2389   (declare (list cdr-of-form))
2390   (let ((name (pop cdr-of-form))
2391         (qualifiers ())
2392         (spec-ll ()))
2393     (loop (if (and (car cdr-of-form) (atom (car cdr-of-form)))
2394               (push (pop cdr-of-form) qualifiers)
2395               (return (setq qualifiers (nreverse qualifiers)))))
2396     (setq spec-ll (pop cdr-of-form))
2397     (values name qualifiers spec-ll cdr-of-form)))
2398
2399 (defun parse-specializers (specializers)
2400   (declare (list specializers))
2401   (flet ((parse (spec)
2402            (let ((result (specializer-from-type spec)))
2403              (if (specializerp result)
2404                  result
2405                  (if (symbolp spec)
2406                      (error "~S was used as a specializer,~%~
2407                              but is not the name of a class."
2408                             spec)
2409                      (error "~S is not a legal specializer." spec))))))
2410     (mapcar #'parse specializers)))
2411
2412 (defun unparse-specializers (specializers-or-method)
2413   (if (listp specializers-or-method)
2414       (flet ((unparse (spec)
2415                (if (specializerp spec)
2416                    (let ((type (specializer-type spec)))
2417                      (if (and (consp type)
2418                               (eq (car type) 'class))
2419                          (let* ((class (cadr type))
2420                                 (class-name (class-name class)))
2421                            (if (eq class (find-class class-name nil))
2422                                class-name
2423                                type))
2424                          type))
2425                    (error "~S is not a legal specializer." spec))))
2426         (mapcar #'unparse specializers-or-method))
2427       (unparse-specializers (method-specializers specializers-or-method))))
2428
2429 (defun parse-method-or-spec (spec &optional (errorp t))
2430   (let (gf method name temp)
2431     (if (method-p spec)
2432         (setq method spec
2433               gf (method-generic-function method)
2434               temp (and gf (generic-function-name gf))
2435               name (if temp
2436                        (make-method-spec temp
2437                                          (method-qualifiers method)
2438                                          (unparse-specializers
2439                                           (method-specializers method)))
2440                        (make-symbol (format nil "~S" method))))
2441         (multiple-value-bind (gf-spec quals specls)
2442             (parse-defmethod spec)
2443           (and (setq gf (and (or errorp (fboundp gf-spec))
2444                              (gdefinition gf-spec)))
2445                (let ((nreq (compute-discriminating-function-arglist-info gf)))
2446                  (setq specls (append (parse-specializers specls)
2447                                       (make-list (- nreq (length specls))
2448                                                  :initial-element
2449                                                  *the-class-t*)))
2450                  (and
2451                    (setq method (get-method gf quals specls errorp))
2452                    (setq name
2453                          (make-method-spec
2454                           gf-spec quals (unparse-specializers specls))))))))
2455     (values gf method name)))
2456 \f
2457 (defun extract-parameters (specialized-lambda-list)
2458   (multiple-value-bind (parameters ignore1 ignore2)
2459       (parse-specialized-lambda-list specialized-lambda-list)
2460     (declare (ignore ignore1 ignore2))
2461     parameters))
2462
2463 (defun extract-lambda-list (specialized-lambda-list)
2464   (multiple-value-bind (ignore1 lambda-list ignore2)
2465       (parse-specialized-lambda-list specialized-lambda-list)
2466     (declare (ignore ignore1 ignore2))
2467     lambda-list))
2468
2469 (defun extract-specializer-names (specialized-lambda-list)
2470   (multiple-value-bind (ignore1 ignore2 specializers)
2471       (parse-specialized-lambda-list specialized-lambda-list)
2472     (declare (ignore ignore1 ignore2))
2473     specializers))
2474
2475 (defun extract-required-parameters (specialized-lambda-list)
2476   (multiple-value-bind (ignore1 ignore2 ignore3 required-parameters)
2477       (parse-specialized-lambda-list specialized-lambda-list)
2478     (declare (ignore ignore1 ignore2 ignore3))
2479     required-parameters))
2480
2481 (define-condition specialized-lambda-list-error
2482     (reference-condition simple-program-error)
2483   ()
2484   (:default-initargs :references (list '(:ansi-cl :section (3 4 3)))))
2485
2486 (defun parse-specialized-lambda-list
2487     (arglist
2488      &optional supplied-keywords (allowed-keywords '(&optional &rest &key &aux))
2489      &aux (specialized-lambda-list-keywords
2490            '(&optional &rest &key &allow-other-keys &aux)))
2491   (let ((arg (car arglist)))
2492     (cond ((null arglist) (values nil nil nil nil))
2493           ((eq arg '&aux)
2494            (values nil arglist nil nil))
2495           ((memq arg lambda-list-keywords)
2496            ;; non-standard lambda-list-keywords are errors.
2497            (unless (memq arg specialized-lambda-list-keywords)
2498              (error 'specialized-lambda-list-error
2499                     :format-control "unknown specialized-lambda-list ~
2500                                      keyword ~S~%"
2501                     :format-arguments (list arg)))
2502            ;; no multiple &rest x &rest bla specifying
2503            (when (memq arg supplied-keywords)
2504              (error 'specialized-lambda-list-error
2505                     :format-control "multiple occurrence of ~
2506                                      specialized-lambda-list keyword ~S~%"
2507                     :format-arguments (list arg)))
2508            ;; And no placing &key in front of &optional, either.
2509            (unless (memq arg allowed-keywords)
2510              (error 'specialized-lambda-list-error
2511                     :format-control "misplaced specialized-lambda-list ~
2512                                      keyword ~S~%"
2513                     :format-arguments (list arg)))
2514            ;; When we are at a lambda-list keyword, the parameters
2515            ;; don't include the lambda-list keyword; the lambda-list
2516            ;; does include the lambda-list keyword; and no
2517            ;; specializers are allowed to follow the lambda-list
2518            ;; keywords (at least for now).
2519            (multiple-value-bind (parameters lambda-list)
2520                (parse-specialized-lambda-list (cdr arglist)
2521                                               (cons arg supplied-keywords)
2522                                               (if (eq arg '&key)
2523                                                   (cons '&allow-other-keys
2524                                                         (cdr (member arg allowed-keywords)))
2525                                                 (cdr (member arg allowed-keywords))))
2526              (when (and (eq arg '&rest)
2527                         (or (null lambda-list)
2528                             (memq (car lambda-list)
2529                                   specialized-lambda-list-keywords)
2530                             (not (or (null (cadr lambda-list))
2531                                      (memq (cadr lambda-list)
2532                                            specialized-lambda-list-keywords)))))
2533                (error 'specialized-lambda-list-error
2534                       :format-control
2535                       "in a specialized-lambda-list, excactly one ~
2536                        variable must follow &REST.~%"
2537                       :format-arguments nil))
2538              (values parameters
2539                      (cons arg lambda-list)
2540                      ()
2541                      ())))
2542           (supplied-keywords
2543            ;; After a lambda-list keyword there can be no specializers.
2544            (multiple-value-bind (parameters lambda-list)
2545                (parse-specialized-lambda-list (cdr arglist)
2546                                               supplied-keywords
2547                                               allowed-keywords)
2548              (values (cons (if (listp arg) (car arg) arg) parameters)
2549                      (cons arg lambda-list)
2550                      ()
2551                      ())))
2552           (t
2553            (multiple-value-bind (parameters lambda-list specializers required)
2554                (parse-specialized-lambda-list (cdr arglist))
2555              (values (cons (if (listp arg) (car arg) arg) parameters)
2556                      (cons (if (listp arg) (car arg) arg) lambda-list)
2557                      (cons (if (listp arg) (cadr arg) t) specializers)
2558                      (cons (if (listp arg) (car arg) arg) required)))))))
2559 \f
2560 (setq *boot-state* 'early)
2561 \f
2562 ;;; FIXME: In here there was a #-CMU definition of SYMBOL-MACROLET
2563 ;;; which used %WALKER stuff. That suggests to me that maybe the code
2564 ;;; walker stuff was only used for implementing stuff like that; maybe
2565 ;;; it's not needed any more? Hunt down what it was used for and see.
2566
2567 (defmacro with-slots (slots instance &body body)
2568   (let ((in (gensym)))
2569     `(let ((,in ,instance))
2570        (declare (ignorable ,in))
2571        ,@(let ((instance (if (and (consp instance) (eq (car instance) 'the))
2572                              (third instance)
2573                              instance)))
2574            (and (symbolp instance)
2575                 `((declare (%variable-rebinding ,in ,instance)))))
2576        ,in
2577        (symbol-macrolet ,(mapcar (lambda (slot-entry)
2578                                    (let ((var-name
2579                                           (if (symbolp slot-entry)
2580                                               slot-entry
2581                                               (car slot-entry)))
2582                                          (slot-name
2583                                           (if (symbolp slot-entry)
2584                                               slot-entry
2585                                               (cadr slot-entry))))
2586                                      `(,var-name
2587                                        (slot-value ,in ',slot-name))))
2588                                  slots)
2589                         ,@body))))
2590
2591 (defmacro with-accessors (slots instance &body body)
2592   (let ((in (gensym)))
2593     `(let ((,in ,instance))
2594        (declare (ignorable ,in))
2595        ,@(let ((instance (if (and (consp instance) (eq (car instance) 'the))
2596                              (third instance)
2597                              instance)))
2598            (and (symbolp instance)
2599                 `((declare (%variable-rebinding ,in ,instance)))))
2600        ,in
2601        (symbol-macrolet ,(mapcar (lambda (slot-entry)
2602                                    (let ((var-name (car slot-entry))
2603                                          (accessor-name (cadr slot-entry)))
2604                                      `(,var-name (,accessor-name ,in))))
2605                                  slots)
2606           ,@body))))