src/pcl/boot.lisp

   1 ;;;; This software is part of the SBCL system. See the README file for
   2 ;;;; more information.
   3
   4 ;;;; This software is derived from software originally released by Xerox
   5 ;;;; Corporation. Copyright and release statements follow. Later modifications
   6 ;;;; to the software are in the public domain and are provided with
   7 ;;;; absolutely no warranty. See the COPYING and CREDITS files for more
   8 ;;;; information.
   9
  10 ;;;; copyright information from original PCL sources:
  11 ;;;;
  12 ;;;; Copyright (c) 1985, 1986, 1987, 1988, 1989, 1990 Xerox Corporation.
  13 ;;;; All rights reserved.
  14 ;;;;
  15 ;;;; Use and copying of this software and preparation of derivative works based
  16 ;;;; upon this software are permitted. Any distribution of this software or
  17 ;;;; derivative works must comply with all applicable United States export
  18 ;;;; control laws.
  19 ;;;;
  20 ;;;; This software is made available AS IS, and Xerox Corporation makes no
  21 ;;;; warranty about the software, its performance or its conformity to any
  22 ;;;; specification.
  23
  24 (in-package "SB-PCL")
  25 \f
  26 #|
  27
  28 The CommonLoops evaluator is meta-circular.
  29
  30 Most of the code in PCL is methods on generic functions, including
  31 most of the code that actually implements generic functions and method
  32 lookup.
  33
  34 So, we have a classic bootstrapping problem. The solution to this is
  35 to first get a cheap implementation of generic functions running,
  36 these are called early generic functions. These early generic
  37 functions and the corresponding early methods and early method lookup
  38 are used to get enough of the system running that it is possible to
  39 create real generic functions and methods and implement real method
  40 lookup. At that point (done in the file FIXUP) the function
  41 !FIX-EARLY-GENERIC-FUNCTIONS is called to convert all the early generic
  42 functions to real generic functions.
  43
  44 The cheap generic functions are built using the same
  45 FUNCALLABLE-INSTANCE objects that real generic functions are made out of.
  46 This means that as PCL is being bootstrapped, the cheap generic
  47 function objects which are being created are the same objects which
  48 will later be real generic functions. This is good because:
  49   - we don't cons garbage structure, and
  50   - we can keep pointers to the cheap generic function objects
  51     during booting because those pointers will still point to
  52     the right object after the generic functions are all fixed up.
  53
  54 This file defines the DEFMETHOD macro and the mechanism used to expand
  55 it. This includes the mechanism for processing the body of a method.
  56 DEFMETHOD basically expands into a call to LOAD-DEFMETHOD, which
  57 basically calls ADD-METHOD to add the method to the generic function.
  58 These expansions can be loaded either during bootstrapping or when PCL
  59 is fully up and running.
  60
  61 An important effect of this arrangement is it means we can compile
  62 files with DEFMETHOD forms in them in a completely running PCL, but
  63 then load those files back in during bootstrapping. This makes
  64 development easier. It also means there is only one set of code for
  65 processing DEFMETHOD. Bootstrapping works by being sure to have
  66 LOAD-METHOD be careful to call only primitives which work during
  67 bootstrapping.
  68
  69 |#
  70
  71 ;;; FIXME: As of sbcl-0.6.9.10, PCL still uses this nonstandard type
  72 ;;; of declaration internally. It would be good to figure out how to
  73 ;;; get rid of it, or failing that, (1) document why it's needed and
  74 ;;; (2) use a private symbol with a forbidding name which suggests
  75 ;;; it's not to be messed with by the user (e.g. SB-PCL:%CLASS)
  76 ;;; instead of the too-inviting CLASS. (I tried just deleting the
  77 ;;; declarations in MAKE-METHOD-LAMBDA-INTERNAL ca. sbcl-0.6.9.10, but
  78 ;;; then things break.)
  79 (declaim (declaration class))
  80
  81 ;;; FIXME: SB-KERNEL::PCL-CHECK-WRAPPER-VALIDITY-HOOK shouldn't be a
  82 ;;; separate function. Instead, we should define a simple placeholder
  83 ;;; version of SB-PCL:CHECK-WRAPPER-VALIDITY where
  84 ;;; SB-KERNEL::PCL-CHECK-WRAPPER-VALIDITY is defined now, then just
  85 ;;; let the later real PCL DEFUN of SB-PCL:CHECK-WRAPPER-VALIDITY
  86 ;;; overwrite it.
  87 (setf (symbol-function 'sb-kernel::pcl-check-wrapper-validity-hook)
  88       #'check-wrapper-validity)
  89
  90 (declaim (notinline make-a-method
  91                     add-named-method
  92                     ensure-generic-function-using-class
  93                     add-method
  94                     remove-method))
  95
  96 (defvar *!early-functions*
  97         '((make-a-method early-make-a-method
  98                          real-make-a-method)
  99           (add-named-method early-add-named-method
 100                             real-add-named-method)
 101           ))
 102
 103 ;;; For each of the early functions, arrange to have it point to its
 104 ;;; early definition. Do this in a way that makes sure that if we
 105 ;;; redefine one of the early definitions the redefinition will take
 106 ;;; effect. This makes development easier.
 107 (dolist (fns *!early-functions*)
 108   (let ((name (car fns))
 109         (early-name (cadr fns)))
 110     (setf (gdefinition name)
 111             (set-fun-name
 112              (lambda (&rest args)
 113                (apply (fdefinition early-name) args))
 114              name))))
 115
 116 ;;; *!GENERIC-FUNCTION-FIXUPS* is used by !FIX-EARLY-GENERIC-FUNCTIONS
 117 ;;; to convert the few functions in the bootstrap which are supposed
 118 ;;; to be generic functions but can't be early on.
 119 (defvar *!generic-function-fixups*
 120   '((add-method
 121      ((generic-function method)  ;lambda-list
 122       (standard-generic-function method) ;specializers
 123       real-add-method))          ;method-function
 124     (remove-method
 125      ((generic-function method)
 126       (standard-generic-function method)
 127       real-remove-method))
 128     (get-method
 129      ((generic-function qualifiers specializers &optional (errorp t))
 130       (standard-generic-function t t)
 131       real-get-method))
 132     (ensure-generic-function-using-class
 133      ((generic-function fun-name
 134                         &key generic-function-class environment
 135                         &allow-other-keys)
 136       (generic-function t)
 137       real-ensure-gf-using-class--generic-function)
 138      ((generic-function fun-name
 139                         &key generic-function-class environment
 140                         &allow-other-keys)
 141       (null t)
 142       real-ensure-gf-using-class--null))
 143     (make-method-lambda
 144      ((proto-generic-function proto-method lambda-expression environment)
 145       (standard-generic-function standard-method t t)
 146       real-make-method-lambda))
 147     (make-method-initargs-form
 148      ((proto-generic-function proto-method
 149                               lambda-expression
 150                               lambda-list environment)
 151       (standard-generic-function standard-method t t t)
 152       real-make-method-initargs-form))
 153     (compute-effective-method
 154      ((generic-function combin applicable-methods)
 155       (generic-function standard-method-combination t)
 156       standard-compute-effective-method))))
 157 \f
 158 (defmacro defgeneric (fun-name lambda-list &body options)
 159   (declare (type list lambda-list))
 160   (unless (legal-fun-name-p fun-name)
 161     (error 'simple-program-error
 162            :format-control "illegal generic function name ~S"
 163            :format-arguments (list fun-name)))
 164   (let ((initargs ())
 165         (methods ()))
 166     (flet ((duplicate-option (name)
 167              (error 'simple-program-error
 168                     :format-control "The option ~S appears more than once."
 169                     :format-arguments (list name)))
 170            (expand-method-definition (qab) ; QAB = qualifiers, arglist, body
 171              (let* ((arglist-pos (position-if #'listp qab))
 172                     (arglist (elt qab arglist-pos))
 173                     (qualifiers (subseq qab 0 arglist-pos))
 174                     (body (nthcdr (1+ arglist-pos) qab)))
 175                `(push (defmethod ,fun-name ,@qualifiers ,arglist ,@body)
 176                       (generic-function-initial-methods #',fun-name)))))
 177       (macrolet ((initarg (key) `(getf initargs ,key)))
 178         (dolist (option options)
 179           (let ((car-option (car option)))
 180             (case car-option
 181               (declare
 182                (push (cdr option) (initarg :declarations)))
 183               ((:argument-precedence-order :method-combination)
 184                (if (initarg car-option)
 185                    (duplicate-option car-option)
 186                    (setf (initarg car-option)
 187                          `',(cdr option))))
 188               ((:documentation :generic-function-class :method-class)
 189                (unless (proper-list-of-length-p option 2)
 190                  (error "bad list length for ~S" option))
 191                (if (initarg car-option)
 192                    (duplicate-option car-option)
 193                    (setf (initarg car-option) `',(cadr option))))
 194               (:method
 195                (push (cdr option) methods))
 196               (t
 197                ;; ANSI requires that unsupported things must get a
 198                ;; PROGRAM-ERROR.
 199                (error 'simple-program-error
 200                       :format-control "unsupported option ~S"
 201                       :format-arguments (list option))))))
 202
 203         (when (initarg :declarations)
 204           (setf (initarg :declarations)
 205                 `',(initarg :declarations))))
 206       `(progn
 207          (eval-when (:compile-toplevel :load-toplevel :execute)
 208            (compile-or-load-defgeneric ',fun-name))
 209          (load-defgeneric ',fun-name ',lambda-list ,@initargs)
 210         ,@(mapcar #'expand-method-definition methods)
 211          #',fun-name))))
 212
 213 (defun compile-or-load-defgeneric (fun-name)
 214   (sb-kernel:proclaim-as-fun-name fun-name)
 215   (sb-kernel:note-name-defined fun-name :function)
 216   (unless (eq (info :function :where-from fun-name) :declared)
 217     (setf (info :function :where-from fun-name) :defined)
 218     (setf (info :function :type fun-name)
 219           (sb-kernel:specifier-type 'function))))
 220
 221 (defun load-defgeneric (fun-name lambda-list &rest initargs)
 222   (when (fboundp fun-name)
 223     (sb-kernel::style-warn "redefining ~S in DEFGENERIC" fun-name)
 224     (let ((fun (fdefinition fun-name)))
 225       (when (generic-function-p fun)
 226         (loop for method in (generic-function-initial-methods fun)
 227               do (remove-method fun method))
 228         (setf (generic-function-initial-methods fun) '()))))
 229   (apply #'ensure-generic-function
 230          fun-name
 231          :lambda-list lambda-list
 232          :definition-source `((defgeneric ,fun-name) ,*load-truename*)
 233          initargs))
 234 \f
 235 (defmacro defmethod (&rest args &environment env)
 236   (multiple-value-bind (name qualifiers lambda-list body)
 237       (parse-defmethod args)
 238     (multiple-value-bind (proto-gf proto-method)
 239         (prototypes-for-make-method-lambda name)
 240       (expand-defmethod name
 241                         proto-gf
 242                         proto-method
 243                         qualifiers
 244                         lambda-list
 245                         body
 246                         env))))
 247
 248 (defun prototypes-for-make-method-lambda (name)
 249   (if (not (eq *boot-state* 'complete))
 250       (values nil nil)
 251       (let ((gf? (and (gboundp name)
 252                       (gdefinition name))))
 253         (if (or (null gf?)
 254                 (not (generic-function-p gf?)))
 255             (values (class-prototype (find-class 'standard-generic-function))
 256                     (class-prototype (find-class 'standard-method)))
 257             (values gf?
 258                     (class-prototype (or (generic-function-method-class gf?)
 259                                          (find-class 'standard-method))))))))
 260
 261 ;;; Take a name which is either a generic function name or a list specifying
 262 ;;; a SETF generic function (like: (SETF <generic-function-name>)). Return
 263 ;;; the prototype instance of the method-class for that generic function.
 264 ;;;
 265 ;;; If there is no generic function by that name, this returns the
 266 ;;; default value, the prototype instance of the class
 267 ;;; STANDARD-METHOD. This default value is also returned if the spec
 268 ;;; names an ordinary function or even a macro. In effect, this leaves
 269 ;;; the signalling of the appropriate error until load time.
 270 ;;;
 271 ;;; Note: During bootstrapping, this function is allowed to return NIL.
 272 (defun method-prototype-for-gf (name)
 273   (let ((gf? (and (gboundp name)
 274                   (gdefinition name))))
 275     (cond ((neq *boot-state* 'complete) nil)
 276           ((or (null gf?)
 277                (not (generic-function-p gf?)))          ; Someone else MIGHT
 278                                                         ; error at load time.
 279            (class-prototype (find-class 'standard-method)))
 280           (t
 281             (class-prototype (or (generic-function-method-class gf?)
 282                                  (find-class 'standard-method)))))))
 283 \f
 284 (defvar *optimize-asv-funcall-p* nil)
 285 (defvar *asv-readers*)
 286 (defvar *asv-writers*)
 287 (defvar *asv-boundps*)
 288
 289 (defun expand-defmethod (name
 290                          proto-gf
 291                          proto-method
 292                          qualifiers
 293                          lambda-list
 294                          body
 295                          env)
 296   (let ((*make-instance-function-keys* nil)
 297         (*optimize-asv-funcall-p* t)
 298         (*asv-readers* nil) (*asv-writers* nil) (*asv-boundps* nil))
 299     (declare (special *make-instance-function-keys*))
 300     (multiple-value-bind (method-lambda unspecialized-lambda-list specializers)
 301         (add-method-declarations name qualifiers lambda-list body env)
 302       (multiple-value-bind (method-function-lambda initargs)
 303           (make-method-lambda proto-gf proto-method method-lambda env)
 304         (let ((initargs-form (make-method-initargs-form proto-gf
 305                                                         proto-method
 306                                                         method-function-lambda
 307                                                         initargs
 308                                                         env)))
 309           `(progn
 310              ;; Note: We could DECLAIM the ftype of the generic
 311              ;; function here, since ANSI specifies that we create it
 312              ;; if it does not exist. However, I chose not to, because
 313              ;; I think it's more useful to support a style of
 314              ;; programming where every generic function has an
 315              ;; explicit DEFGENERIC and any typos in DEFMETHODs are
 316              ;; warned about. Otherwise
 317              ;;   (DEFGENERIC FOO-BAR-BLETCH ((X T)))
 318              ;;   (DEFMETHOD FOO-BAR-BLETCH ((X HASH-TABLE)) ..)
 319              ;;   (DEFMETHOD FOO-BRA-BLETCH ((X SIMPLE-VECTOR)) ..)
 320              ;;   (DEFMETHOD FOO-BAR-BLETCH ((X VECTOR)) ..)
 321              ;;   (DEFMETHOD FOO-BAR-BLETCH ((X ARRAY)) ..)
 322              ;;   (DEFMETHOD FOO-BAR-BLETCH ((X LIST)) ..)
 323              ;; compiles without raising an error and runs without
 324              ;; raising an error (since SIMPLE-VECTOR cases fall
 325              ;; through to VECTOR) but still doesn't do what was
 326              ;; intended. I hate that kind of bug (code which silently
 327              ;; gives the wrong answer), so we don't do a DECLAIM
 328              ;; here. -- WHN 20000229
 329              ,@(when *make-instance-function-keys*
 330                  `((get-make-instance-functions
 331                     ',*make-instance-function-keys*)))
 332              ,@(when (or *asv-readers* *asv-writers* *asv-boundps*)
 333                  `((initialize-internal-slot-gfs*
 334                     ',*asv-readers* ',*asv-writers* ',*asv-boundps*)))
 335              ,(make-defmethod-form name qualifiers specializers
 336                                    unspecialized-lambda-list
 337                                    (if proto-method
 338                                        (class-name (class-of proto-method))
 339                                        'standard-method)
 340                                    initargs-form
 341                                    (getf (getf initargs :plist)
 342                                          :pv-table-symbol))))))))
 343
 344 (defun interned-symbol-p (x)
 345   (and (symbolp x) (symbol-package x)))
 346
 347 (defun make-defmethod-form (name qualifiers specializers
 348                                  unspecialized-lambda-list method-class-name
 349                                  initargs-form &optional pv-table-symbol)
 350   (let (fn
 351         fn-lambda)
 352     (if (and (interned-symbol-p (fun-name-block-name name))
 353              (every #'interned-symbol-p qualifiers)
 354              (every (lambda (s)
 355                       (if (consp s)
 356                           (and (eq (car s) 'eql)
 357                                (constantp (cadr s))
 358                                (let ((sv (eval (cadr s))))
 359                                  (or (interned-symbol-p sv)
 360                                      (integerp sv)
 361                                      (and (characterp sv)
 362                                           (standard-char-p sv)))))
 363                           (interned-symbol-p s)))
 364                     specializers)
 365              (consp initargs-form)
 366              (eq (car initargs-form) 'list*)
 367              (memq (cadr initargs-form) '(:function :fast-function))
 368              (consp (setq fn (caddr initargs-form)))
 369              (eq (car fn) 'function)
 370              (consp (setq fn-lambda (cadr fn)))
 371              (eq (car fn-lambda) 'lambda))
 372         (let* ((specls (mapcar (lambda (specl)
 373                                  (if (consp specl)
 374                                      `(,(car specl) ,(eval (cadr specl)))
 375                                    specl))
 376                                specializers))
 377                (mname `(,(if (eq (cadr initargs-form) :function)
 378                              'method 'fast-method)
 379                         ,name ,@qualifiers ,specls))
 380                (mname-sym (intern (let ((*print-pretty* nil)
 381                                         ;; (We bind *PACKAGE* to
 382                                         ;; KEYWORD here as a way to
 383                                         ;; force symbols to be printed
 384                                         ;; with explicit package
 385                                         ;; prefixes.)
 386                                         (*package* *keyword-package*))
 387                                     (format nil "~S" mname)))))
 388           `(progn
 389              (defun ,mname-sym ,(cadr fn-lambda)
 390                ,@(cddr fn-lambda))
 391              ,(make-defmethod-form-internal
 392                name qualifiers `',specls
 393                unspecialized-lambda-list method-class-name
 394                `(list* ,(cadr initargs-form)
 395                        #',mname-sym
 396                        ,@(cdddr initargs-form))
 397                pv-table-symbol)))
 398         (make-defmethod-form-internal
 399          name qualifiers
 400          `(list ,@(mapcar (lambda (specializer)
 401                             (if (consp specializer)
 402                                 ``(,',(car specializer)
 403                                    ,,(cadr specializer))
 404                                 `',specializer))
 405                           specializers))
 406          unspecialized-lambda-list
 407          method-class-name
 408          initargs-form
 409          pv-table-symbol))))
 410
 411 (defun make-defmethod-form-internal
 412     (name qualifiers specializers-form unspecialized-lambda-list
 413      method-class-name initargs-form &optional pv-table-symbol)
 414   `(load-defmethod
 415     ',method-class-name
 416     ',name
 417     ',qualifiers
 418     ,specializers-form
 419     ',unspecialized-lambda-list
 420     ,initargs-form
 421     ;; Paper over a bug in KCL by passing the cache-symbol here in
 422     ;; addition to in the list. FIXME: We should no longer need to do
 423     ;; this, since the CLOS code is now SBCL-specific, and doesn't
 424     ;; need to be ported to every buggy compiler in existence.
 425     ',pv-table-symbol))
 426
 427 (defmacro make-method-function (method-lambda &environment env)
 428   (make-method-function-internal method-lambda env))
 429
 430 (defun make-method-function-internal (method-lambda &optional env)
 431   (multiple-value-bind (proto-gf proto-method)
 432       (prototypes-for-make-method-lambda nil)
 433     (multiple-value-bind (method-function-lambda initargs)
 434         (make-method-lambda proto-gf proto-method method-lambda env)
 435       (make-method-initargs-form proto-gf
 436                                  proto-method
 437                                  method-function-lambda
 438                                  initargs
 439                                  env))))
 440
 441 (defun add-method-declarations (name qualifiers lambda-list body env)
 442   (multiple-value-bind (parameters unspecialized-lambda-list specializers)
 443       (parse-specialized-lambda-list lambda-list)
 444     (declare (ignore parameters))
 445     (multiple-value-bind (documentation declarations real-body)
 446         (extract-declarations body env)
 447       (values `(lambda ,unspecialized-lambda-list
 448                  ,@(when documentation `(,documentation))
 449                  ;; (Old PCL code used a somewhat different style of
 450                  ;; list for %METHOD-NAME values. Our names use
 451                  ;; ,@QUALIFIERS instead of ,QUALIFIERS so that the
 452                  ;; method names look more like what you see in a
 453                  ;; DEFMETHOD form.)
 454                  ;;
 455                  ;; FIXME: As of sbcl-0.7.0.6, code elsewhere, at
 456                  ;; least the code to set up named BLOCKs around the
 457                  ;; bodies of methods, depends on the function's base
 458                  ;; name being the first element of the %METHOD-NAME
 459                  ;; list. It would be good to remove this dependency,
 460                  ;; perhaps by building the BLOCK here, or by using
 461                  ;; another declaration (e.g. %BLOCK-NAME), so that
 462                  ;; our method debug names are free to have any format,
 463                  ;; e.g. (:METHOD PRINT-OBJECT :AROUND (CLOWN T)).
 464                  (declare (%method-name (,name
 465                                          ,@qualifiers
 466                                          ,specializers)))
 467                  (declare (%method-lambda-list ,@lambda-list))
 468                  ,@declarations
 469                  ,@real-body)
 470               unspecialized-lambda-list specializers))))
 471
 472 (defun real-make-method-initargs-form (proto-gf proto-method
 473                                        method-lambda initargs env)
 474   (declare (ignore proto-gf proto-method))
 475   (unless (and (consp method-lambda)
 476                (eq (car method-lambda) 'lambda))
 477     (error "The METHOD-LAMBDA argument to MAKE-METHOD-FUNCTION, ~S, ~
 478             is not a lambda form."
 479            method-lambda))
 480   (make-method-initargs-form-internal method-lambda initargs env))
 481
 482 (unless (fboundp 'make-method-initargs-form)
 483   (setf (gdefinition 'make-method-initargs-form)
 484         (symbol-function 'real-make-method-initargs-form)))
 485
 486 (defun real-make-method-lambda (proto-gf proto-method method-lambda env)
 487   (declare (ignore proto-gf proto-method))
 488   (make-method-lambda-internal method-lambda env))
 489
 490 ;;; a helper function for creating Python-friendly type declarations
 491 ;;; in DEFMETHOD forms
 492 (defun parameter-specializer-declaration-in-defmethod (parameter specializer)
 493   (cond ((and (consp specializer)
 494               (eq (car specializer) 'eql))
 495          ;; KLUDGE: ANSI, in its wisdom, says that
 496          ;; EQL-SPECIALIZER-FORMs in EQL specializers are evaluated at
 497          ;; DEFMETHOD expansion time. Thus, although one might think
 498          ;; that in
 499          ;;   (DEFMETHOD FOO ((X PACKAGE)
 500          ;;                   (Y (EQL 12))
 501          ;;      ..))
 502          ;; the PACKAGE and (EQL 12) forms are both parallel type
 503          ;; names, they're not, as is made clear when you do
 504          ;;   (DEFMETHOD FOO ((X PACKAGE)
 505          ;;                   (Y (EQL 'BAR)))
 506          ;;     ..)
 507          ;; where Y needs to be a symbol named "BAR", not some cons
 508          ;; made by (CONS 'QUOTE 'BAR). I.e. when the
 509          ;; EQL-SPECIALIZER-FORM is (EQL 'X), it requires an argument
 510          ;; to be of type (EQL X). It'd be easy to transform one to
 511          ;; the other, but it'd be somewhat messier to do so while
 512          ;; ensuring that the EQL-SPECIALIZER-FORM is only EVAL'd
 513          ;; once. (The new code wouldn't be messy, but it'd require a
 514          ;; big transformation of the old code.) So instead we punt.
 515          ;; -- WHN 20000610
 516          '(ignorable))
 517         ((member specializer
 518                  ;; KLUDGE: For some low-level implementation
 519                  ;; classes, perhaps because of some problems related
 520                  ;; to the incomplete integration of PCL into SBCL's
 521                  ;; type system, some specializer classes can't be
 522                  ;; declared as argument types. E.g.
 523                  ;;   (DEFMETHOD FOO ((X SLOT-OBJECT))
 524                  ;;     (DECLARE (TYPE SLOT-OBJECT X))
 525                  ;;     ..)
 526                  ;; loses when
 527                  ;;   (DEFSTRUCT BAR A B)
 528                  ;;   (FOO (MAKE-BAR))
 529                  ;; perhaps because of the way that STRUCTURE-OBJECT
 530                  ;; inherits both from SLOT-OBJECT and from
 531                  ;; SB-KERNEL:INSTANCE. In an effort to sweep such
 532                  ;; problems under the rug, we exclude these problem
 533                  ;; cases by blacklisting them here. -- WHN 2001-01-19
 534                  '(slot-object))
 535          '(ignorable))
 536         ((not (eq *boot-state* 'complete))
 537          ;; KLUDGE: PCL, in its wisdom, sometimes calls methods with
 538          ;; types which don't match their specializers. (Specifically,
 539          ;; it calls ENSURE-CLASS-USING-CLASS (T NULL) with a non-NULL
 540          ;; second argument.) Hopefully it only does this kind of
 541          ;; weirdness when bootstrapping.. -- WHN 20000610
 542          '(ignorable))
 543         (t
 544          ;; Otherwise, we can make Python very happy.
 545          `(type ,specializer ,parameter))))
 546
 547 (defun make-method-lambda-internal (method-lambda &optional env)
 548   (unless (and (consp method-lambda) (eq (car method-lambda) 'lambda))
 549     (error "The METHOD-LAMBDA argument to MAKE-METHOD-LAMBDA, ~S, ~
 550             is not a lambda form."
 551            method-lambda))
 552   (multiple-value-bind (documentation declarations real-body)
 553       (extract-declarations (cddr method-lambda) env)
 554     (let* ((name-decl (get-declaration '%method-name declarations))
 555            (sll-decl (get-declaration '%method-lambda-list declarations))
 556            (method-name (when (consp name-decl) (car name-decl)))
 557            (generic-function-name (when method-name (car method-name)))
 558            (specialized-lambda-list (or sll-decl (cadr method-lambda))))
 559       (multiple-value-bind (parameters lambda-list specializers)
 560           (parse-specialized-lambda-list specialized-lambda-list)
 561         (let* ((required-parameters
 562                 (mapcar (lambda (r s) (declare (ignore s)) r)
 563                         parameters
 564                         specializers))
 565                (slots (mapcar #'list required-parameters))
 566                (calls (list nil))
 567                (class-declarations
 568                 `(declare
 569                   ;; These declarations seem to be used by PCL to pass
 570                   ;; information to itself; when I tried to delete 'em
 571                   ;; ca. 0.6.10 it didn't work. I'm not sure how
 572                   ;; they work, but note the (VAR-DECLARATION '%CLASS ..)
 573                   ;; expression in CAN-OPTIMIZE-ACCESS1. -- WHN 2000-12-30
 574                   ,@(remove nil
 575                             (mapcar (lambda (a s) (and (symbolp s)
 576                                                        (neq s t)
 577                                                        `(%class ,a ,s)))
 578                                     parameters
 579                                     specializers))
 580                   ;; These TYPE declarations weren't in the original
 581                   ;; PCL code, but the Python compiler likes them a
 582                   ;; lot. (We're telling the compiler about our
 583                   ;; knowledge of specialized argument types so that
 584                   ;; it can avoid run-time type dispatch overhead,
 585                   ;; which can be a huge win for Python.)
 586                   ;;
 587                   ;; FIXME: Perhaps these belong in
 588                   ;; ADD-METHOD-DECLARATIONS instead of here?
 589                   ,@(mapcar #'parameter-specializer-declaration-in-defmethod
 590                             parameters
 591                             specializers)))
 592                (method-lambda
 593                 ;; Remove the documentation string and insert the
 594                 ;; appropriate class declarations. The documentation
 595                 ;; string is removed to make it easy for us to insert
 596                 ;; new declarations later, they will just go after the
 597                 ;; CADR of the method lambda. The class declarations
 598                 ;; are inserted to communicate the class of the method's
 599                 ;; arguments to the code walk.
 600                 `(lambda ,lambda-list
 601                    ;; The default ignorability of method parameters
 602                    ;; doesn't seem to be specified by ANSI. PCL had
 603                    ;; them basically ignorable but was a little
 604                    ;; inconsistent. E.g. even though the two
 605                    ;; method definitions
 606                    ;;   (DEFMETHOD FOO ((X T) (Y T)) "Z")
 607                    ;;   (DEFMETHOD FOO ((X T) Y) "Z")
 608                    ;; are otherwise equivalent, PCL treated Y as
 609                    ;; ignorable in the first definition but not in the
 610                    ;; second definition. We make all required
 611                    ;; parameters ignorable as a way of systematizing
 612                    ;; the old PCL behavior. -- WHN 2000-11-24
 613                    (declare (ignorable ,@required-parameters))
 614                    ,class-declarations
 615                    ,@declarations
 616                    (block ,(fun-name-block-name generic-function-name)
 617                      ,@real-body)))
 618                (constant-value-p (and (null (cdr real-body))
 619                                       (constantp (car real-body))))
 620                (constant-value (and constant-value-p
 621                                     (eval (car real-body))))
 622                (plist (and constant-value-p
 623                            (or (typep constant-value
 624                                       '(or number character))
 625                                (and (symbolp constant-value)
 626                                     (symbol-package constant-value)))
 627                            (list :constant-value constant-value)))
 628                (applyp (dolist (p lambda-list nil)
 629                          (cond ((memq p '(&optional &rest &key))
 630                                 (return t))
 631                                ((eq p '&aux)
 632                                 (return nil))))))
 633           (multiple-value-bind
 634               (walked-lambda call-next-method-p closurep next-method-p-p)
 635               (walk-method-lambda method-lambda
 636                                   required-parameters
 637                                   env
 638                                   slots
 639                                   calls)
 640             (multiple-value-bind
 641                 (ignore walked-declarations walked-lambda-body)
 642                 (extract-declarations (cddr walked-lambda))
 643               (declare (ignore ignore))
 644               (when (or next-method-p-p call-next-method-p)
 645                 (setq plist (list* :needs-next-methods-p t plist)))
 646               (when (some #'cdr slots)
 647                 (multiple-value-bind (slot-name-lists call-list)
 648                     (slot-name-lists-from-slots slots calls)
 649                   (let ((pv-table-symbol (make-symbol "pv-table")))
 650                     (setq plist
 651                           `(,@(when slot-name-lists
 652                                 `(:slot-name-lists ,slot-name-lists))
 653                               ,@(when call-list
 654                                   `(:call-list ,call-list))
 655                               :pv-table-symbol ,pv-table-symbol
 656                               ,@plist))
 657                     (setq walked-lambda-body
 658                           `((pv-binding (,required-parameters
 659                                          ,slot-name-lists
 660                                          ,pv-table-symbol)
 661                                         ,@walked-lambda-body))))))
 662               (when (and (memq '&key lambda-list)
 663                          (not (memq '&allow-other-keys lambda-list)))
 664                 (let ((aux (memq '&aux lambda-list)))
 665                 (setq lambda-list (nconc (ldiff lambda-list aux)
 666                                          (list '&allow-other-keys)
 667                                          aux))))
 668               (values `(lambda (.method-args. .next-methods.)
 669                          (simple-lexical-method-functions
 670                           (,lambda-list .method-args. .next-methods.
 671                                         :call-next-method-p
 672                                         ,call-next-method-p
 673                                         :next-method-p-p ,next-method-p-p
 674                                         :closurep ,closurep
 675                                         :applyp ,applyp)
 676                           ,@walked-declarations
 677                           ,@walked-lambda-body))
 678                       `(,@(when plist
 679                       `(:plist ,plist))
 680                           ,@(when documentation
 681                           `(:documentation ,documentation)))))))))))
 682
 683 (unless (fboundp 'make-method-lambda)
 684   (setf (gdefinition 'make-method-lambda)
 685         (symbol-function 'real-make-method-lambda)))
 686
 687 (defmacro simple-lexical-method-functions ((lambda-list
 688                                             method-args
 689                                             next-methods
 690                                             &rest lmf-options)
 691                                            &body body)
 692   `(progn
 693      ,method-args ,next-methods
 694      (bind-simple-lexical-method-macros (,method-args ,next-methods)
 695        (bind-lexical-method-functions (,@lmf-options)
 696          (bind-args (,lambda-list ,method-args)
 697            ,@body)))))
 698
 699 (defmacro fast-lexical-method-functions ((lambda-list
 700                                           next-method-call
 701                                           args
 702                                           rest-arg
 703                                           &rest lmf-options)
 704                                          &body body)
 705   `(bind-fast-lexical-method-macros (,args ,rest-arg ,next-method-call)
 706      (bind-lexical-method-functions (,@lmf-options)
 707        (bind-args (,(nthcdr (length args) lambda-list) ,rest-arg)
 708          ,@body))))
 709
 710 (defmacro bind-simple-lexical-method-macros ((method-args next-methods)
 711                                              &body body)
 712   `(macrolet ((call-next-method-bind (&body body)
 713                 `(let ((.next-method. (car ,',next-methods))
 714                        (,',next-methods (cdr ,',next-methods)))
 715                    .next-method. ,',next-methods
 716                    ,@body))
 717               (call-next-method-body (cnm-args)
 718                 `(if .next-method.
 719                      (funcall (if (std-instance-p .next-method.)
 720                                   (method-function .next-method.)
 721                                   .next-method.) ; for early methods
 722                               (or ,cnm-args ,',method-args)
 723                               ,',next-methods)
 724                      (error "no next method")))
 725               (next-method-p-body ()
 726                 `(not (null .next-method.))))
 727      ,@body))
 728
 729 (defstruct (method-call (:copier nil))
 730   (function #'identity :type function)
 731   call-method-args)
 732
 733 #-sb-fluid (declaim (sb-ext:freeze-type method-call))
 734
 735 (defmacro invoke-method-call1 (function args cm-args)
 736   `(let ((.function. ,function)
 737          (.args. ,args)
 738          (.cm-args. ,cm-args))
 739      (if (and .cm-args. (null (cdr .cm-args.)))
 740          (funcall .function. .args. (car .cm-args.))
 741          (apply .function. .args. .cm-args.))))
 742
 743 (defmacro invoke-method-call (method-call restp &rest required-args+rest-arg)
 744   `(invoke-method-call1 (method-call-function ,method-call)
 745                         ,(if restp
 746                              `(list* ,@required-args+rest-arg)
 747                              `(list ,@required-args+rest-arg))
 748                         (method-call-call-method-args ,method-call)))
 749
 750 (defstruct (fast-method-call (:copier nil))
 751   (function #'identity :type function)
 752   pv-cell
 753   next-method-call
 754   arg-info)
 755
 756 #-sb-fluid (declaim (sb-ext:freeze-type fast-method-call))
 757
 758 (defmacro fmc-funcall (fn pv-cell next-method-call &rest args)
 759   `(funcall ,fn ,pv-cell ,next-method-call ,@args))
 760
 761 (defmacro invoke-fast-method-call (method-call &rest required-args+rest-arg)
 762   `(fmc-funcall (fast-method-call-function ,method-call)
 763                 (fast-method-call-pv-cell ,method-call)
 764                 (fast-method-call-next-method-call ,method-call)
 765                 ,@required-args+rest-arg))
 766
 767 (defstruct (fast-instance-boundp (:copier nil))
 768   (index 0 :type fixnum))
 769
 770 #-sb-fluid (declaim (sb-ext:freeze-type fast-instance-boundp))
 771
 772 (eval-when (:compile-toplevel :load-toplevel :execute)
 773   (defvar *allow-emf-call-tracing-p* nil)
 774   (defvar *enable-emf-call-tracing-p* #-sb-show nil #+sb-show t))
 775 \f
 776 ;;;; effective method functions
 777
 778 (defvar *emf-call-trace-size* 200)
 779 (defvar *emf-call-trace* nil)
 780 (defvar *emf-call-trace-index* 0)
 781
 782 ;;; This function was in the CMU CL version of PCL (ca Debian 2.4.8)
 783 ;;; without explanation. It appears to be intended for debugging, so
 784 ;;; it might be useful someday, so I haven't deleted it.
 785 ;;; But it isn't documented and isn't used for anything now, so
 786 ;;; I've conditionalized it out of the base system. -- WHN 19991213
 787 #+sb-show
 788 (defun show-emf-call-trace ()
 789   (when *emf-call-trace*
 790     (let ((j *emf-call-trace-index*)
 791           (*enable-emf-call-tracing-p* nil))
 792       (format t "~&(The oldest entries are printed first)~%")
 793       (dotimes-fixnum (i *emf-call-trace-size*)
 794         (let ((ct (aref *emf-call-trace* j)))
 795           (when ct (print ct)))
 796         (incf j)
 797         (when (= j *emf-call-trace-size*)
 798           (setq j 0))))))
 799
 800 (defun trace-emf-call-internal (emf format args)
 801   (unless *emf-call-trace*
 802     (setq *emf-call-trace* (make-array *emf-call-trace-size*)))
 803   (setf (aref *emf-call-trace* *emf-call-trace-index*)
 804         (list* emf format args))
 805   (incf *emf-call-trace-index*)
 806   (when (= *emf-call-trace-index* *emf-call-trace-size*)
 807     (setq *emf-call-trace-index* 0)))
 808
 809 (defmacro trace-emf-call (emf format args)
 810   (when *allow-emf-call-tracing-p*
 811     `(when *enable-emf-call-tracing-p*
 812        (trace-emf-call-internal ,emf ,format ,args))))
 813
 814 (defmacro invoke-effective-method-function-fast
 815     (emf restp &rest required-args+rest-arg)
 816   `(progn
 817      (trace-emf-call ,emf ,restp (list ,@required-args+rest-arg))
 818      (invoke-fast-method-call ,emf ,@required-args+rest-arg)))
 819
 820 (defmacro invoke-effective-method-function (emf restp
 821                                                 &rest required-args+rest-arg)
 822   (unless (constantp restp)
 823     (error "The RESTP argument is not constant."))
 824   ;; FIXME: The RESTP handling here is confusing and maybe slightly
 825   ;; broken if RESTP evaluates to a non-self-evaluating form. E.g. if
 826   ;;   (INVOKE-EFFECTIVE-METHOD-FUNCTION EMF '(ERROR "gotcha") ...)
 827   ;; then TRACE-EMF-CALL-CALL-INTERNAL might die on a gotcha error.
 828   (setq restp (eval restp))
 829   `(progn
 830      (trace-emf-call ,emf ,restp (list ,@required-args+rest-arg))
 831      (cond ((typep ,emf 'fast-method-call)
 832             (invoke-fast-method-call ,emf ,@required-args+rest-arg))
 833            ;; "What," you may wonder, "do these next two clauses do?"
 834            ;; In that case, you are not a PCL implementor, for they
 835            ;; considered this to be self-documenting.:-| Or CSR, for
 836            ;; that matter, since he can also figure it out by looking
 837            ;; at it without breaking stride. For the rest of us,
 838            ;; though: From what the code is doing with .SLOTS. and
 839            ;; whatnot, evidently it's implementing SLOT-VALUEish and
 840            ;; GET-SLOT-VALUEish things. Then we can reason backwards
 841            ;; and conclude that setting EMF to a FIXNUM is an
 842            ;; optimized way to represent these slot access operations.
 843            ,@(when (and (null restp) (= 1 (length required-args+rest-arg)))
 844                `(((typep ,emf 'fixnum)
 845                   (let* ((.slots. (get-slots-or-nil
 846                                    ,(car required-args+rest-arg)))
 847                          (value (when .slots. (clos-slots-ref .slots. ,emf))))
 848                     (if (eq value +slot-unbound+)
 849                         (slot-unbound-internal ,(car required-args+rest-arg)
 850                                                ,emf)
 851                         value)))))
 852            ,@(when (and (null restp) (= 2 (length required-args+rest-arg)))
 853                `(((typep ,emf 'fixnum)
 854                   (let ((.new-value. ,(car required-args+rest-arg))
 855                         (.slots. (get-slots-or-nil
 856                                   ,(car required-args+rest-arg))))
 857                     (when .slots.
 858                       (setf (clos-slots-ref .slots. ,emf) .new-value.))))))
 859            ;; (In cmucl-2.4.8 there was a commented-out third ,@(WHEN
 860            ;; ...) clause here to handle SLOT-BOUNDish stuff. Since
 861            ;; there was no explanation and presumably the code is 10+
 862            ;; years stale, I simply deleted it. -- WHN)
 863            (t
 864             (etypecase ,emf
 865               (method-call
 866                (invoke-method-call ,emf ,restp ,@required-args+rest-arg))
 867               (function
 868                ,(if restp
 869                     `(apply (the function ,emf) ,@required-args+rest-arg)
 870                     `(funcall (the function ,emf)
 871                               ,@required-args+rest-arg))))))))
 872
 873 (defun invoke-emf (emf args)
 874   (trace-emf-call emf t args)
 875   (etypecase emf
 876     (fast-method-call
 877      (let* ((arg-info (fast-method-call-arg-info emf))
 878             (restp (cdr arg-info))
 879             (nreq (car arg-info)))
 880        (if restp
 881            (let* ((rest-args (nthcdr nreq args))
 882                   (req-args (ldiff args rest-args)))
 883              (apply (fast-method-call-function emf)
 884                     (fast-method-call-pv-cell emf)
 885                     (fast-method-call-next-method-call emf)
 886                     (nconc req-args (list rest-args))))
 887            (cond ((null args)
 888                   (if (eql nreq 0)
 889                       (invoke-fast-method-call emf)
 890                       (error "wrong number of args")))
 891                  ((null (cdr args))
 892                   (if (eql nreq 1)
 893                       (invoke-fast-method-call emf (car args))
 894                       (error "wrong number of args")))
 895                  ((null (cddr args))
 896                   (if (eql nreq 2)
 897                       (invoke-fast-method-call emf (car args) (cadr args))
 898                       (error "wrong number of args")))
 899                  (t
 900                   (apply (fast-method-call-function emf)
 901                          (fast-method-call-pv-cell emf)
 902                          (fast-method-call-next-method-call emf)
 903                          args))))))
 904     (method-call
 905      (apply (method-call-function emf)
 906             args
 907             (method-call-call-method-args emf)))
 908     (fixnum
 909      (cond ((null args) (error "1 or 2 args were expected."))
 910            ((null (cdr args))
 911             (let* ((slots (get-slots (car args)))
 912                    (value (clos-slots-ref slots emf)))
 913               (if (eq value +slot-unbound+)
 914                   (slot-unbound-internal (car args) emf)
 915                   value)))
 916            ((null (cddr args))
 917              (setf (clos-slots-ref (get-slots (cadr args)) emf)
 918                    (car args)))
 919            (t (error "1 or 2 args were expected."))))
 920     (fast-instance-boundp
 921      (if (or (null args) (cdr args))
 922          (error "1 arg was expected.")
 923        (let ((slots (get-slots (car args))))
 924          (not (eq (clos-slots-ref slots
 925                                   (fast-instance-boundp-index emf))
 926                   +slot-unbound+)))))
 927     (function
 928      (apply emf args))))
 929
 930 ;; KLUDGE: A comment from the original PCL said "This can be improved alot."
 931 (defun gf-make-function-from-emf (gf emf)
 932   (etypecase emf
 933     (fast-method-call (let* ((arg-info (gf-arg-info gf))
 934                              (nreq (arg-info-number-required arg-info))
 935                              (restp (arg-info-applyp arg-info)))
 936                         (lambda (&rest args)
 937                           (trace-emf-call emf t args)
 938                           (apply (fast-method-call-function emf)
 939                                  (fast-method-call-pv-cell emf)
 940                                  (fast-method-call-next-method-call emf)
 941                                  (if restp
 942                                      (let* ((rest-args (nthcdr nreq args))
 943                                             (req-args (ldiff args
 944                                                              rest-args)))
 945                                        (nconc req-args rest-args))
 946                                      args)))))
 947     (method-call (lambda (&rest args)
 948                    (trace-emf-call emf t args)
 949                    (apply (method-call-function emf)
 950                           args
 951                           (method-call-call-method-args emf))))
 952     (function emf)))
 953 \f
 954 (defmacro bind-fast-lexical-method-macros ((args rest-arg next-method-call)
 955                                            &body body)
 956   `(macrolet ((narrowed-emf (emf)
 957                 ;; INVOKE-EFFECTIVE-METHOD-FUNCTION has code in it to
 958                 ;; dispatch on the possibility that EMF might be of
 959                 ;; type FIXNUM (as an optimized representation of a
 960                 ;; slot accessor). But as far as I (WHN 2002-06-11)
 961                 ;; can tell, it's impossible for such a representation
 962                 ;; to end up as .NEXT-METHOD-CALL. By reassuring
 963                 ;; INVOKE-E-M-F that when called from this context
 964                 ;; it needn't worry about the FIXNUM case, we can
 965                 ;; keep those cases from being compiled, which is
 966                 ;; good both because it saves bytes and because it
 967                 ;; avoids annoying type mismatch compiler warnings.
 968                 ;;
 969                 ;; KLUDGE: In sbcl-0.7.4.29, the compiler's type
 970                 ;; system isn't smart enough about NOT and intersection
 971                 ;; types to benefit from a (NOT FIXNUM) declaration
 972                 ;; here. -- WHN 2002-06-12
 973                 ;;
 974                 ;; FIXME: Might the FUNCTION type be omittable here,
 975                 ;; leaving only METHOD-CALLs? Failing that, could this
 976                 ;; be documented somehow? (It'd be nice if the types
 977                 ;; involved could be understood without solving the
 978                 ;; halting problem.)
 979                 `(the (or function method-call fast-method-call)
 980                    ,emf))
 981               (call-next-method-bind (&body body)
 982                `(let () ,@body))
 983               (call-next-method-body (cnm-args)
 984                `(if ,',next-method-call
 985                  ,(locally
 986                    ;; This declaration suppresses a "deleting
 987                    ;; unreachable code" note for the following IF when
 988                    ;; REST-ARG is NIL. It is not nice for debugging
 989                    ;; SBCL itself, but at least it keeps us from
 990                    ;; annoying users.
 991                    (declare (optimize (inhibit-warnings 3)))
 992                    (if (and (null ',rest-arg)
 993                             (consp cnm-args)
 994                             (eq (car cnm-args) 'list))
 995                        `(invoke-effective-method-function
 996                          (narrowed-emf ,',next-method-call)
 997                          nil
 998                          ,@(cdr cnm-args))
 999                        (let ((call `(invoke-effective-method-function
1000                                      (narrowed-emf ,',next-method-call)
1001                                      ,',(not (null rest-arg))
1002                                      ,@',args
1003                                      ,@',(when rest-arg `(,rest-arg)))))
1004                          `(if ,cnm-args
1005                            (bind-args ((,@',args
1006                                         ,@',(when rest-arg
1007                                               `(&rest ,rest-arg)))
1008                                        ,cnm-args)
1009                             ,call)
1010                            ,call))))
1011                  (error "no next method")))
1012               (next-method-p-body ()
1013                `(not (null ,',next-method-call))))
1014     ,@body))
1015
1016 (defmacro bind-lexical-method-functions
1017     ((&key call-next-method-p next-method-p-p closurep applyp)
1018      &body body)
1019   (cond ((and (null call-next-method-p) (null next-method-p-p)
1020               (null closurep)
1021               (null applyp))
1022          `(let () ,@body))
1023         ((and (null closurep)
1024               (null applyp))
1025          ;; OK to use MACROLET, and all args are mandatory
1026          ;; (else APPLYP would be true).
1027          `(call-next-method-bind
1028             (macrolet ((call-next-method (&rest cnm-args)
1029                          `(call-next-method-body ,(when cnm-args
1030                                                     `(list ,@cnm-args))))
1031                        (next-method-p ()
1032                          `(next-method-p-body)))
1033                ,@body)))
1034         (t
1035          `(call-next-method-bind
1036             (flet (,@(and call-next-method-p
1037                           '((call-next-method (&rest cnm-args)
1038                               (call-next-method-body cnm-args))))
1039                    ,@(and next-method-p-p
1040                           '((next-method-p ()
1041                               (next-method-p-body)))))
1042               ,@body)))))
1043
1044 (defmacro bind-args ((lambda-list args) &body body)
1045   (let ((args-tail '.args-tail.)
1046         (key '.key.)
1047         (state 'required))
1048     (flet ((process-var (var)
1049              (if (memq var lambda-list-keywords)
1050                  (progn
1051                    (case var
1052                      (&optional       (setq state 'optional))
1053                      (&key            (setq state 'key))
1054                      (&allow-other-keys)
1055                      (&rest           (setq state 'rest))
1056                      (&aux            (setq state 'aux))
1057                      (otherwise
1058                       (error
1059                        "encountered the non-standard lambda list keyword ~S"
1060                        var)))
1061                    nil)
1062                  (case state
1063                    (required `((,var (pop ,args-tail))))
1064                    (optional (cond ((not (consp var))
1065                                     `((,var (when ,args-tail
1066                                               (pop ,args-tail)))))
1067                                    ((null (cddr var))
1068                                     `((,(car var) (if ,args-tail
1069                                                       (pop ,args-tail)
1070                                                       ,(cadr var)))))
1071                                    (t
1072                                     `((,(caddr var) ,args-tail)
1073                                       (,(car var) (if ,args-tail
1074                                                       (pop ,args-tail)
1075                                                       ,(cadr var)))))))
1076                    (rest `((,var ,args-tail)))
1077                    (key (cond ((not (consp var))
1078                                `((,var (get-key-arg ,(keywordicate var)
1079                                                     ,args-tail))))
1080                               ((null (cddr var))
1081                                (multiple-value-bind (keyword variable)
1082                                    (if (consp (car var))
1083                                        (values (caar var)
1084                                                (cadar var))
1085                                        (values (keywordicate (car var))
1086                                                (car var)))
1087                                  `((,key (get-key-arg1 ',keyword ,args-tail))
1088                                    (,variable (if (consp ,key)
1089                                                   (car ,key)
1090                                                   ,(cadr var))))))
1091                               (t
1092                                (multiple-value-bind (keyword variable)
1093                                    (if (consp (car var))
1094                                        (values (caar var)
1095                                                (cadar var))
1096                                        (values (keywordicate (car var))
1097                                                (car var)))
1098                                  `((,key (get-key-arg1 ',keyword ,args-tail))
1099                                    (,(caddr var) ,key)
1100                                    (,variable (if (consp ,key)
1101                                                   (car ,key)
1102                                                   ,(cadr var))))))))
1103                    (aux `(,var))))))
1104       (let ((bindings (mapcan #'process-var lambda-list)))
1105         `(let* ((,args-tail ,args)
1106                 ,@bindings)
1107            (declare (ignorable ,args-tail))
1108            ,@body)))))
1109
1110 (defun get-key-arg (keyword list)
1111   (loop (when (atom list) (return nil))
1112         (when (eq (car list) keyword) (return (cadr list)))
1113         (setq list (cddr list))))
1114
1115 (defun get-key-arg1 (keyword list)
1116   (loop (when (atom list) (return nil))
1117         (when (eq (car list) keyword) (return (cdr list)))
1118         (setq list (cddr list))))
1119
1120 (defun walk-method-lambda (method-lambda required-parameters env slots calls)
1121   (let ((call-next-method-p nil)   ; flag indicating that CALL-NEXT-METHOD
1122                                    ; should be in the method definition
1123         (closurep nil)             ; flag indicating that #'CALL-NEXT-METHOD
1124                                    ; was seen in the body of a method
1125         (next-method-p-p nil))     ; flag indicating that NEXT-METHOD-P
1126                                    ; should be in the method definition
1127     (flet ((walk-function (form context env)
1128              (cond ((not (eq context :eval)) form)
1129                    ;; FIXME: Jumping to a conclusion from the way it's used
1130                    ;; above, perhaps CONTEXT should be called SITUATION
1131                    ;; (after the term used in the ANSI specification of
1132                    ;; EVAL-WHEN) and given modern ANSI keyword values
1133                    ;; like :LOAD-TOPLEVEL.
1134                    ((not (listp form)) form)
1135                    ((eq (car form) 'call-next-method)
1136                     (setq call-next-method-p t)
1137                     form)
1138                    ((eq (car form) 'next-method-p)
1139                     (setq next-method-p-p t)
1140                     form)
1141                    ((and (eq (car form) 'function)
1142                          (cond ((eq (cadr form) 'call-next-method)
1143                                 (setq call-next-method-p t)
1144                                 (setq closurep t)
1145                                 form)
1146                                ((eq (cadr form) 'next-method-p)
1147                                 (setq next-method-p-p t)
1148                                 (setq closurep t)
1149                                 form)
1150                                (t nil))))
1151                    ((and (memq (car form)
1152                                '(slot-value set-slot-value slot-boundp))
1153                          (constantp (caddr form)))
1154                      (let ((parameter (can-optimize-access form
1155                                                            required-parameters
1156                                                            env)))
1157                       (let ((fun (ecase (car form)
1158                                    (slot-value #'optimize-slot-value)
1159                                    (set-slot-value #'optimize-set-slot-value)
1160                                    (slot-boundp #'optimize-slot-boundp))))
1161                         (funcall fun slots parameter form))))
1162                    ((and (eq (car form) 'apply)
1163                          (consp (cadr form))
1164                          (eq (car (cadr form)) 'function)
1165                          (generic-function-name-p (cadr (cadr form))))
1166                     (optimize-generic-function-call
1167                      form required-parameters env slots calls))
1168                    ((generic-function-name-p (car form))
1169                     (optimize-generic-function-call
1170                      form required-parameters env slots calls))
1171                    ((and (eq (car form) 'asv-funcall)
1172                          *optimize-asv-funcall-p*)
1173                     (case (fourth form)
1174                       (reader (push (third form) *asv-readers*))
1175                       (writer (push (third form) *asv-writers*))
1176                       (boundp (push (third form) *asv-boundps*)))
1177                     `(,(second form) ,@(cddddr form)))
1178                    (t form))))
1179
1180       (let ((walked-lambda (walk-form method-lambda env #'walk-function)))
1181         (values walked-lambda
1182                 call-next-method-p
1183                 closurep
1184                 next-method-p-p)))))
1185
1186 (defun generic-function-name-p (name)
1187   (and (legal-fun-name-p name)
1188        (gboundp name)
1189        (if (eq *boot-state* 'complete)
1190            (standard-generic-function-p (gdefinition name))
1191            (funcallable-instance-p (gdefinition name)))))
1192 \f
1193 (defvar *method-function-plist* (make-hash-table :test 'eq))
1194 (defvar *mf1* nil)
1195 (defvar *mf1p* nil)
1196 (defvar *mf1cp* nil)
1197 (defvar *mf2* nil)
1198 (defvar *mf2p* nil)
1199 (defvar *mf2cp* nil)
1200
1201 (defun method-function-plist (method-function)
1202   (unless (eq method-function *mf1*)
1203     (rotatef *mf1* *mf2*)
1204     (rotatef *mf1p* *mf2p*)
1205     (rotatef *mf1cp* *mf2cp*))
1206   (unless (or (eq method-function *mf1*) (null *mf1cp*))
1207     (setf (gethash *mf1* *method-function-plist*) *mf1p*))
1208   (unless (eq method-function *mf1*)
1209     (setf *mf1* method-function
1210           *mf1cp* nil
1211           *mf1p* (gethash method-function *method-function-plist*)))
1212   *mf1p*)
1213
1214 (defun (setf method-function-plist)
1215     (val method-function)
1216   (unless (eq method-function *mf1*)
1217     (rotatef *mf1* *mf2*)
1218     (rotatef *mf1cp* *mf2cp*)
1219     (rotatef *mf1p* *mf2p*))
1220   (unless (or (eq method-function *mf1*) (null *mf1cp*))
1221     (setf (gethash *mf1* *method-function-plist*) *mf1p*))
1222   (setf *mf1* method-function
1223         *mf1cp* t
1224         *mf1p* val))
1225
1226 (defun method-function-get (method-function key &optional default)
1227   (getf (method-function-plist method-function) key default))
1228
1229 (defun (setf method-function-get)
1230     (val method-function key)
1231   (setf (getf (method-function-plist method-function) key) val))
1232
1233 (defun method-function-pv-table (method-function)
1234   (method-function-get method-function :pv-table))
1235
1236 (defun method-function-method (method-function)
1237   (method-function-get method-function :method))
1238
1239 (defun method-function-needs-next-methods-p (method-function)
1240   (method-function-get method-function :needs-next-methods-p t))
1241 \f
1242 (defmacro method-function-closure-generator (method-function)
1243   `(method-function-get ,method-function 'closure-generator))
1244
1245 (defun load-defmethod
1246     (class name quals specls ll initargs &optional pv-table-symbol)
1247   (setq initargs (copy-tree initargs))
1248   (let ((method-spec (or (getf initargs :method-spec)
1249                          (make-method-spec name quals specls))))
1250     (setf (getf initargs :method-spec) method-spec)
1251     (load-defmethod-internal class name quals specls
1252                              ll initargs pv-table-symbol)))
1253
1254 (defun load-defmethod-internal
1255     (method-class gf-spec qualifiers specializers lambda-list
1256                   initargs pv-table-symbol)
1257   (when pv-table-symbol
1258     (setf (getf (getf initargs :plist) :pv-table-symbol)
1259           pv-table-symbol))
1260   (when (and (eq *boot-state* 'complete)
1261              (fboundp gf-spec))
1262     (let* ((gf (fdefinition gf-spec))
1263            (method (and (generic-function-p gf)
1264                         (find-method gf
1265                                      qualifiers
1266                                      (parse-specializers specializers)
1267                                      nil))))
1268       (when method
1269         (sb-kernel::style-warn "redefining ~S~{ ~S~} ~S in DEFMETHOD"
1270                                gf-spec qualifiers specializers))))
1271   (let ((method (apply #'add-named-method
1272                        gf-spec qualifiers specializers lambda-list
1273                        :definition-source `((defmethod ,gf-spec
1274                                                 ,@qualifiers
1275                                               ,specializers)
1276                                             ,*load-truename*)
1277                        initargs)))
1278     (unless (or (eq method-class 'standard-method)
1279                 (eq (find-class method-class nil) (class-of method)))
1280       ;; FIXME: should be STYLE-WARNING?
1281       (format *error-output*
1282               "~&At the time the method with qualifiers ~:S and~%~
1283                specializers ~:S on the generic function ~S~%~
1284                was compiled, the method-class for that generic function was~%~
1285                ~S. But, the method class is now ~S, this~%~
1286                may mean that this method was compiled improperly.~%"
1287               qualifiers specializers gf-spec
1288               method-class (class-name (class-of method))))
1289     method))
1290
1291 (defun make-method-spec (gf-spec qualifiers unparsed-specializers)
1292   `(method ,gf-spec ,@qualifiers ,unparsed-specializers))
1293
1294 (defun initialize-method-function (initargs &optional return-function-p method)
1295   (let* ((mf (getf initargs :function))
1296          (method-spec (getf initargs :method-spec))
1297          (plist (getf initargs :plist))
1298          (pv-table-symbol (getf plist :pv-table-symbol))
1299          (pv-table nil)
1300          (mff (getf initargs :fast-function)))
1301     (flet ((set-mf-property (p v)
1302              (when mf
1303                (setf (method-function-get mf p) v))
1304              (when mff
1305                (setf (method-function-get mff p) v))))
1306       (when method-spec
1307         (when mf
1308           (setq mf (set-fun-name mf method-spec)))
1309         (when mff
1310           (let ((name `(,(or (get (car method-spec) 'fast-sym)
1311                              (setf (get (car method-spec) 'fast-sym)
1312                                    ;; KLUDGE: If we're going to be
1313                                    ;; interning private symbols in our
1314                                    ;; a this way, it would be cleanest
1315                                    ;; to use a separate package
1316                                    ;; %PCL-PRIVATE or something, and
1317                                    ;; failing that, to use a special
1318                                    ;; symbol prefix denoting privateness.
1319                                    ;; -- WHN 19991201
1320                                    (intern (format nil "FAST-~A"
1321                                                    (car method-spec))
1322                                            *pcl-package*)))
1323                          ,@(cdr method-spec))))
1324             (set-fun-name mff name)
1325             (unless mf
1326               (set-mf-property :name name)))))
1327       (when plist
1328         (let ((snl (getf plist :slot-name-lists))
1329               (cl (getf plist :call-list)))
1330           (when (or snl cl)
1331             (setq pv-table (intern-pv-table :slot-name-lists snl
1332                                             :call-list cl))
1333             (when pv-table (set pv-table-symbol pv-table))
1334             (set-mf-property :pv-table pv-table)))
1335         (loop (when (null plist) (return nil))
1336               (set-mf-property (pop plist) (pop plist)))
1337         (when method
1338           (set-mf-property :method method))
1339         (when return-function-p
1340           (or mf (method-function-from-fast-function mff)))))))
1341 \f
1342 (defun analyze-lambda-list (lambda-list)
1343   (flet (;; FIXME: Is this redundant with SB-C::MAKE-KEYWORD-FOR-ARG?
1344          (parse-key-arg (arg)
1345            (if (listp arg)
1346                (if (listp (car arg))
1347                    (caar arg)
1348                    (keywordicate (car arg)))
1349                (keywordicate arg))))
1350     (let ((nrequired 0)
1351           (noptional 0)
1352           (keysp nil)
1353           (restp nil)
1354           (nrest 0)
1355           (allow-other-keys-p nil)
1356           (keywords ())
1357           (keyword-parameters ())
1358           (state 'required))
1359       (dolist (x lambda-list)
1360         (if (memq x lambda-list-keywords)
1361             (case x
1362               (&optional         (setq state 'optional))
1363               (&key              (setq keysp t
1364                                        state 'key))
1365               (&allow-other-keys (setq allow-other-keys-p t))
1366               (&rest             (setq restp t
1367                                        state 'rest))
1368               (&aux           (return t))
1369               (otherwise
1370                 (error "encountered the non-standard lambda list keyword ~S"
1371                        x)))
1372             (ecase state
1373               (required  (incf nrequired))
1374               (optional  (incf noptional))
1375               (key       (push (parse-key-arg x) keywords)
1376                          (push x keyword-parameters))
1377               (rest      (incf nrest)))))
1378       (when (and restp (zerop nrest))
1379         (error "Error in lambda-list:~%~
1380                 After &REST, a DEFGENERIC lambda-list ~
1381                 must be followed by at least one variable."))
1382       (values nrequired noptional keysp restp allow-other-keys-p
1383               (reverse keywords)
1384               (reverse keyword-parameters)))))
1385
1386 (defun keyword-spec-name (x)
1387   (let ((key (if (atom x) x (car x))))
1388     (if (atom key)
1389         (keywordicate key)
1390         (car key))))
1391
1392 (defun ftype-declaration-from-lambda-list (lambda-list name)
1393   (multiple-value-bind (nrequired noptional keysp restp allow-other-keys-p
1394                                   keywords keyword-parameters)
1395       (analyze-lambda-list lambda-list)
1396     (declare (ignore keyword-parameters))
1397     (let* ((old (info :function :type name)) ;FIXME:FDOCUMENTATION instead?
1398            (old-ftype (if (sb-kernel:fun-type-p old) old nil))
1399            (old-restp (and old-ftype (sb-kernel:fun-type-rest old-ftype)))
1400            (old-keys (and old-ftype
1401                           (mapcar #'sb-kernel:key-info-name
1402                                   (sb-kernel:fun-type-keywords
1403                                    old-ftype))))
1404            (old-keysp (and old-ftype (sb-kernel:fun-type-keyp old-ftype)))
1405            (old-allowp (and old-ftype
1406                             (sb-kernel:fun-type-allowp old-ftype)))
1407            (keywords (union old-keys (mapcar #'keyword-spec-name keywords))))
1408       `(function ,(append (make-list nrequired :initial-element t)
1409                           (when (plusp noptional)
1410                             (append '(&optional)
1411                                     (make-list noptional :initial-element t)))
1412                           (when (or restp old-restp)
1413                             '(&rest t))
1414                           (when (or keysp old-keysp)
1415                             (append '(&key)
1416                                     (mapcar (lambda (key)
1417                                               `(,key t))
1418                                             keywords)
1419                                     (when (or allow-other-keys-p old-allowp)
1420                                       '(&allow-other-keys)))))
1421                  *))))
1422
1423 (defun defgeneric-declaration (spec lambda-list)
1424   (when (consp spec)
1425     (setq spec (get-setf-fun-name (cadr spec))))
1426   `(ftype ,(ftype-declaration-from-lambda-list lambda-list spec) ,spec))
1427 \f
1428 ;;;; early generic function support
1429
1430 (defvar *!early-generic-functions* ())
1431
1432 (defun ensure-generic-function (fun-name
1433                                 &rest all-keys
1434                                 &key environment
1435                                 &allow-other-keys)
1436   (declare (ignore environment))
1437   (let ((existing (and (gboundp fun-name)
1438                        (gdefinition fun-name))))
1439     (if (and existing
1440              (eq *boot-state* 'complete)
1441              (null (generic-function-p existing)))
1442         (generic-clobbers-function fun-name)
1443         (apply #'ensure-generic-function-using-class
1444                existing fun-name all-keys))))
1445
1446 (defun generic-clobbers-function (fun-name)
1447   (error 'simple-program-error
1448          :format-control "~S already names an ordinary function or a macro."
1449          :format-arguments (list fun-name)))
1450
1451 (defvar *sgf-wrapper*
1452   (boot-make-wrapper (early-class-size 'standard-generic-function)
1453                      'standard-generic-function))
1454
1455 (defvar *sgf-slots-init*
1456   (mapcar (lambda (canonical-slot)
1457             (if (memq (getf canonical-slot :name) '(arg-info source))
1458                 +slot-unbound+
1459                 (let ((initfunction (getf canonical-slot :initfunction)))
1460                   (if initfunction
1461                       (funcall initfunction)
1462                       +slot-unbound+))))
1463           (early-collect-inheritance 'standard-generic-function)))
1464
1465 (defvar *sgf-method-class-index*
1466   (!bootstrap-slot-index 'standard-generic-function 'method-class))
1467
1468 (defun early-gf-p (x)
1469   (and (fsc-instance-p x)
1470        (eq (clos-slots-ref (get-slots x) *sgf-method-class-index*)
1471            +slot-unbound+)))
1472
1473 (defvar *sgf-methods-index*
1474   (!bootstrap-slot-index 'standard-generic-function 'methods))
1475
1476 (defmacro early-gf-methods (gf)
1477   `(clos-slots-ref (get-slots ,gf) *sgf-methods-index*))
1478
1479 (defvar *sgf-arg-info-index*
1480   (!bootstrap-slot-index 'standard-generic-function 'arg-info))
1481
1482 (defmacro early-gf-arg-info (gf)
1483   `(clos-slots-ref (get-slots ,gf) *sgf-arg-info-index*))
1484
1485 (defvar *sgf-dfun-state-index*
1486   (!bootstrap-slot-index 'standard-generic-function 'dfun-state))
1487
1488 (defstruct (arg-info
1489             (:conc-name nil)
1490             (:constructor make-arg-info ())
1491             (:copier nil))
1492   (arg-info-lambda-list :no-lambda-list)
1493   arg-info-precedence
1494   arg-info-metatypes
1495   arg-info-number-optional
1496   arg-info-key/rest-p
1497   arg-info-keys   ;nil        no &KEY or &REST allowed
1498                   ;(k1 k2 ..) Each method must accept these &KEY arguments.
1499                   ;T          must have &KEY or &REST
1500
1501   gf-info-simple-accessor-type ; nil, reader, writer, boundp
1502   (gf-precompute-dfun-and-emf-p nil) ; set by set-arg-info
1503
1504   gf-info-static-c-a-m-emf
1505   (gf-info-c-a-m-emf-std-p t)
1506   gf-info-fast-mf-p)
1507
1508 #-sb-fluid (declaim (sb-ext:freeze-type arg-info))
1509
1510 (defun arg-info-valid-p (arg-info)
1511   (not (null (arg-info-number-optional arg-info))))
1512
1513 (defun arg-info-applyp (arg-info)
1514   (or (plusp (arg-info-number-optional arg-info))
1515       (arg-info-key/rest-p arg-info)))
1516
1517 (defun arg-info-number-required (arg-info)
1518   (length (arg-info-metatypes arg-info)))
1519
1520 (defun arg-info-nkeys (arg-info)
1521   (count-if (lambda (x) (neq x t)) (arg-info-metatypes arg-info)))
1522
1523 ;;; Keep pages clean by not setting if the value is already the same.
1524 (defmacro esetf (pos val)
1525   (let ((valsym (gensym "value")))
1526     `(let ((,valsym ,val))
1527        (unless (equal ,pos ,valsym)
1528          (setf ,pos ,valsym)))))
1529
1530 (defun set-arg-info (gf &key new-method (lambda-list nil lambda-list-p)
1531                         argument-precedence-order)
1532   (let* ((arg-info (if (eq *boot-state* 'complete)
1533                        (gf-arg-info gf)
1534                        (early-gf-arg-info gf)))
1535          (methods (if (eq *boot-state* 'complete)
1536                       (generic-function-methods gf)
1537                       (early-gf-methods gf)))
1538          (was-valid-p (integerp (arg-info-number-optional arg-info)))
1539          (first-p (and new-method (null (cdr methods)))))
1540     (when (and (not lambda-list-p) methods)
1541       (setq lambda-list (gf-lambda-list gf)))
1542     (when (or lambda-list-p
1543               (and first-p
1544                    (eq (arg-info-lambda-list arg-info) :no-lambda-list)))
1545       (multiple-value-bind (nreq nopt keysp restp allow-other-keys-p keywords)
1546           (analyze-lambda-list lambda-list)
1547         (when (and methods (not first-p))
1548           (let ((gf-nreq (arg-info-number-required arg-info))
1549                 (gf-nopt (arg-info-number-optional arg-info))
1550                 (gf-key/rest-p (arg-info-key/rest-p arg-info)))
1551             (unless (and (= nreq gf-nreq)
1552                          (= nopt gf-nopt)
1553                          (eq (or keysp restp) gf-key/rest-p))
1554               (error "The lambda-list ~S is incompatible with ~
1555                      existing methods of ~S."
1556                      lambda-list gf))))
1557         (when lambda-list-p
1558           (esetf (arg-info-lambda-list arg-info) lambda-list))
1559         (when (or lambda-list-p argument-precedence-order
1560                   (null (arg-info-precedence arg-info)))
1561           (esetf (arg-info-precedence arg-info)
1562                  (compute-precedence lambda-list nreq
1563                                      argument-precedence-order)))
1564         (esetf (arg-info-metatypes arg-info) (make-list nreq))
1565         (esetf (arg-info-number-optional arg-info) nopt)
1566         (esetf (arg-info-key/rest-p arg-info) (not (null (or keysp restp))))
1567         (esetf (arg-info-keys arg-info)
1568                (if lambda-list-p
1569                    (if allow-other-keys-p t keywords)
1570                    (arg-info-key/rest-p arg-info)))))
1571     (when new-method
1572       (check-method-arg-info gf arg-info new-method))
1573     (set-arg-info1 gf arg-info new-method methods was-valid-p first-p)
1574     arg-info))
1575
1576 (defun check-method-arg-info (gf arg-info method)
1577   (multiple-value-bind (nreq nopt keysp restp allow-other-keys-p keywords)
1578       (analyze-lambda-list (if (consp method)
1579                                (early-method-lambda-list method)
1580                                (method-lambda-list method)))
1581     (flet ((lose (string &rest args)
1582              (error
1583               "attempt to add the method ~S to the generic function ~S.~%~
1584                But ~A"
1585               method
1586               gf
1587               (apply #'format nil string args)))
1588            (comparison-description (x y)
1589              (if (> x y) "more" "fewer")))
1590       (let ((gf-nreq (arg-info-number-required arg-info))
1591             (gf-nopt (arg-info-number-optional arg-info))
1592             (gf-key/rest-p (arg-info-key/rest-p arg-info))
1593             (gf-keywords (arg-info-keys arg-info)))
1594         (unless (= nreq gf-nreq)
1595           (lose
1596            "the method has ~A required arguments than the generic function."
1597            (comparison-description nreq gf-nreq)))
1598         (unless (= nopt gf-nopt)
1599           (lose
1600            "the method has ~A optional arguments than the generic function."
1601            (comparison-description nopt gf-nopt)))
1602         (unless (eq (or keysp restp) gf-key/rest-p)
1603           (error
1604            "The method and generic function differ in whether they accept~%~
1605             &REST or &KEY arguments."))
1606         (when (consp gf-keywords)
1607           (unless (or (and restp (not keysp))
1608                       allow-other-keys-p
1609                       (every (lambda (k) (memq k keywords)) gf-keywords))
1610             (lose "the method does not accept each of the &KEY arguments~%~
1611                    ~S."
1612                   gf-keywords)))))))
1613
1614 (defun set-arg-info1 (gf arg-info new-method methods was-valid-p first-p)
1615   (let* ((existing-p (and methods (cdr methods) new-method))
1616          (nreq (length (arg-info-metatypes arg-info)))
1617          (metatypes (if existing-p
1618                         (arg-info-metatypes arg-info)
1619                         (make-list nreq)))
1620          (type (if existing-p
1621                    (gf-info-simple-accessor-type arg-info)
1622                    nil)))
1623     (when (arg-info-valid-p arg-info)
1624       (dolist (method (if new-method (list new-method) methods))
1625         (let* ((specializers (if (or (eq *boot-state* 'complete)
1626                                      (not (consp method)))
1627                                  (method-specializers method)
1628                                  (early-method-specializers method t)))
1629                (class (if (or (eq *boot-state* 'complete) (not (consp method)))
1630                           (class-of method)
1631                           (early-method-class method)))
1632                (new-type (when (and class
1633                                     (or (not (eq *boot-state* 'complete))
1634                                         (eq (generic-function-method-combination gf)
1635                                             *standard-method-combination*)))
1636                            (cond ((eq class *the-class-standard-reader-method*)
1637                                   'reader)
1638                                  ((eq class *the-class-standard-writer-method*)
1639                                   'writer)
1640                                  ((eq class *the-class-standard-boundp-method*)
1641                                   'boundp)))))
1642           (setq metatypes (mapcar #'raise-metatype metatypes specializers))
1643           (setq type (cond ((null type) new-type)
1644                            ((eq type new-type) type)
1645                            (t nil)))))
1646       (esetf (arg-info-metatypes arg-info) metatypes)
1647       (esetf (gf-info-simple-accessor-type arg-info) type)))
1648   (when (or (not was-valid-p) first-p)
1649     (multiple-value-bind (c-a-m-emf std-p)
1650         (if (early-gf-p gf)
1651             (values t t)
1652             (compute-applicable-methods-emf gf))
1653       (esetf (gf-info-static-c-a-m-emf arg-info) c-a-m-emf)
1654       (esetf (gf-info-c-a-m-emf-std-p arg-info) std-p)
1655       (unless (gf-info-c-a-m-emf-std-p arg-info)
1656         (esetf (gf-info-simple-accessor-type arg-info) t))))
1657   (unless was-valid-p
1658     (let ((name (if (eq *boot-state* 'complete)
1659                     (generic-function-name gf)
1660                     (!early-gf-name gf))))
1661       (esetf (gf-precompute-dfun-and-emf-p arg-info)
1662              (let* ((sym (if (atom name) name (cadr name)))
1663                     (pkg-list (cons *pcl-package*
1664                                     (package-use-list *pcl-package*))))
1665                (and sym (symbolp sym)
1666                     (not (null (memq (symbol-package sym) pkg-list)))
1667                     (not (find #\space (symbol-name sym))))))))
1668   (esetf (gf-info-fast-mf-p arg-info)
1669          (or (not (eq *boot-state* 'complete))
1670              (let* ((method-class (generic-function-method-class gf))
1671                     (methods (compute-applicable-methods
1672                               #'make-method-lambda
1673                               (list gf (class-prototype method-class)
1674                                     '(lambda) nil))))
1675                (and methods (null (cdr methods))
1676                     (let ((specls (method-specializers (car methods))))
1677                       (and (classp (car specls))
1678                            (eq 'standard-generic-function
1679                                (class-name (car specls)))
1680                            (classp (cadr specls))
1681                            (eq 'standard-method
1682                                (class-name (cadr specls)))))))))
1683   arg-info)
1684
1685 ;;; This is the early definition of ENSURE-GENERIC-FUNCTION-USING-CLASS.
1686 ;;;
1687 ;;; The STATIC-SLOTS field of the funcallable instances used as early
1688 ;;; generic functions is used to store the early methods and early
1689 ;;; discriminator code for the early generic function. The static
1690 ;;; slots field of the fins contains a list whose:
1691 ;;;    CAR    -   a list of the early methods on this early gf
1692 ;;;    CADR   -   the early discriminator code for this method
1693 (defun ensure-generic-function-using-class (existing spec &rest keys
1694                                             &key (lambda-list nil
1695                                                               lambda-list-p)
1696                                             &allow-other-keys)
1697   (declare (ignore keys))
1698   (cond ((and existing (early-gf-p existing))
1699          existing)
1700         ((assoc spec *!generic-function-fixups* :test #'equal)
1701          (if existing
1702              (make-early-gf spec lambda-list lambda-list-p existing)
1703              (error "The function ~S is not already defined." spec)))
1704         (existing
1705          (error "~S should be on the list ~S."
1706                 spec
1707                 '*!generic-function-fixups*))
1708         (t
1709          (pushnew spec *!early-generic-functions* :test #'equal)
1710          (make-early-gf spec lambda-list lambda-list-p))))
1711
1712 (defun make-early-gf (spec &optional lambda-list lambda-list-p function)
1713   (let ((fin (allocate-funcallable-instance *sgf-wrapper* *sgf-slots-init*)))
1714     (set-funcallable-instance-fun
1715      fin
1716      (or function
1717          (if (eq spec 'print-object)
1718              #'(sb-kernel:instance-lambda (instance stream)
1719                  (print-unreadable-object (instance stream :identity t)
1720                    (format stream "std-instance")))
1721              #'(sb-kernel:instance-lambda (&rest args)
1722                  (declare (ignore args))
1723                  (error "The function of the funcallable-instance ~S~
1724                          has not been set." fin)))))
1725     (setf (gdefinition spec) fin)
1726     (!bootstrap-set-slot 'standard-generic-function fin 'name spec)
1727     (!bootstrap-set-slot 'standard-generic-function
1728                          fin
1729                          'source
1730                          *load-truename*)
1731     (set-fun-name fin spec)
1732     (let ((arg-info (make-arg-info)))
1733       (setf (early-gf-arg-info fin) arg-info)
1734       (when lambda-list-p
1735         (proclaim (defgeneric-declaration spec lambda-list))
1736         (set-arg-info fin :lambda-list lambda-list)))
1737     fin))
1738
1739 (defun set-dfun (gf &optional dfun cache info)
1740   (when cache
1741     (setf (cache-owner cache) gf))
1742   (let ((new-state (if (and dfun (or cache info))
1743                        (list* dfun cache info)
1744                        dfun)))
1745     (if (eq *boot-state* 'complete)
1746         (setf (gf-dfun-state gf) new-state)
1747         (setf (clos-slots-ref (get-slots gf) *sgf-dfun-state-index*)
1748               new-state)))
1749   dfun)
1750
1751 (defun gf-dfun-cache (gf)
1752   (let ((state (if (eq *boot-state* 'complete)
1753                    (gf-dfun-state gf)
1754                    (clos-slots-ref (get-slots gf) *sgf-dfun-state-index*))))
1755     (typecase state
1756       (function nil)
1757       (cons (cadr state)))))
1758
1759 (defun gf-dfun-info (gf)
1760   (let ((state (if (eq *boot-state* 'complete)
1761                    (gf-dfun-state gf)
1762                    (clos-slots-ref (get-slots gf) *sgf-dfun-state-index*))))
1763     (typecase state
1764       (function nil)
1765       (cons (cddr state)))))
1766
1767 (defvar *sgf-name-index*
1768   (!bootstrap-slot-index 'standard-generic-function 'name))
1769
1770 (defun !early-gf-name (gf)
1771   (clos-slots-ref (get-slots gf) *sgf-name-index*))
1772
1773 (defun gf-lambda-list (gf)
1774   (let ((arg-info (if (eq *boot-state* 'complete)
1775                       (gf-arg-info gf)
1776                       (early-gf-arg-info gf))))
1777     (if (eq :no-lambda-list (arg-info-lambda-list arg-info))
1778         (let ((methods (if (eq *boot-state* 'complete)
1779                            (generic-function-methods gf)
1780                            (early-gf-methods gf))))
1781           (if (null methods)
1782               (progn
1783                 (warn "no way to determine the lambda list for ~S" gf)
1784                 nil)
1785               (let* ((method (car (last methods)))
1786                      (ll (if (consp method)
1787                              (early-method-lambda-list method)
1788                              (method-lambda-list method)))
1789                      (k (member '&key ll)))
1790                 (if k
1791                     (append (ldiff ll (cdr k)) '(&allow-other-keys))
1792                     ll))))
1793         (arg-info-lambda-list arg-info))))
1794
1795 (defmacro real-ensure-gf-internal (gf-class all-keys env)
1796   `(progn
1797      (cond ((symbolp ,gf-class)
1798             (setq ,gf-class (find-class ,gf-class t ,env)))
1799            ((classp ,gf-class))
1800            (t
1801             (error "The :GENERIC-FUNCTION-CLASS argument (~S) was neither a~%~
1802                     class nor a symbol that names a class."
1803                    ,gf-class)))
1804      (remf ,all-keys :generic-function-class)
1805      (remf ,all-keys :environment)
1806      (let ((combin (getf ,all-keys :method-combination '.shes-not-there.)))
1807        (unless (eq combin '.shes-not-there.)
1808          (setf (getf ,all-keys :method-combination)
1809                (find-method-combination (class-prototype ,gf-class)
1810                                         (car combin)
1811                                         (cdr combin)))))
1812     (let ((method-class (getf ,all-keys :method-class '.shes-not-there.)))
1813       (unless (eq method-class '.shes-not-there.)
1814         (setf (getf ,all-keys :method-class)
1815                 (find-class method-class t ,env))))))
1816
1817 (defun real-ensure-gf-using-class--generic-function
1818        (existing
1819         fun-name
1820         &rest all-keys
1821         &key environment (lambda-list nil lambda-list-p)
1822              (generic-function-class 'standard-generic-function gf-class-p)
1823         &allow-other-keys)
1824   (real-ensure-gf-internal generic-function-class all-keys environment)
1825   (unless (or (null gf-class-p)
1826               (eq (class-of existing) generic-function-class))
1827     (change-class existing generic-function-class))
1828   (prog1
1829       (apply #'reinitialize-instance existing all-keys)
1830     (when lambda-list-p
1831       (proclaim (defgeneric-declaration fun-name lambda-list)))))
1832
1833 (defun real-ensure-gf-using-class--null
1834        (existing
1835         fun-name
1836         &rest all-keys
1837         &key environment (lambda-list nil lambda-list-p)
1838              (generic-function-class 'standard-generic-function)
1839         &allow-other-keys)
1840   (declare (ignore existing))
1841   (real-ensure-gf-internal generic-function-class all-keys environment)
1842   (prog1
1843       (setf (gdefinition fun-name)
1844             (apply #'make-instance generic-function-class
1845                    :name fun-name all-keys))
1846     (when lambda-list-p
1847       (proclaim (defgeneric-declaration fun-name lambda-list)))))
1848 \f
1849 (defun get-generic-fun-info (gf)
1850   ;; values   nreq applyp metatypes nkeys arg-info
1851   (multiple-value-bind (applyp metatypes arg-info)
1852       (let* ((arg-info (if (early-gf-p gf)
1853                            (early-gf-arg-info gf)
1854                            (gf-arg-info gf)))
1855              (metatypes (arg-info-metatypes arg-info)))
1856         (values (arg-info-applyp arg-info)
1857                 metatypes
1858                 arg-info))
1859     (values (length metatypes) applyp metatypes
1860             (count-if (lambda (x) (neq x t)) metatypes)
1861             arg-info)))
1862
1863 (defun early-make-a-method (class qualifiers arglist specializers initargs doc
1864                             &optional slot-name)
1865   (initialize-method-function initargs)
1866   (let ((parsed ())
1867         (unparsed ()))
1868     ;; Figure out whether we got class objects or class names as the
1869     ;; specializers and set parsed and unparsed appropriately. If we
1870     ;; got class objects, then we can compute unparsed, but if we got
1871     ;; class names we don't try to compute parsed.
1872     ;;
1873     ;; Note that the use of not symbolp in this call to every should be
1874     ;; read as 'classp' we can't use classp itself because it doesn't
1875     ;; exist yet.
1876     (if (every (lambda (s) (not (symbolp s))) specializers)
1877         (setq parsed specializers
1878               unparsed (mapcar (lambda (s)
1879                                  (if (eq s t) t (class-name s)))
1880                                specializers))
1881         (setq unparsed specializers
1882               parsed ()))
1883     (list :early-method           ;This is an early method dammit!
1884
1885           (getf initargs :function)
1886           (getf initargs :fast-function)
1887
1888           parsed                  ;The parsed specializers. This is used
1889                                   ;by early-method-specializers to cache
1890                                   ;the parse. Note that this only comes
1891                                   ;into play when there is more than one
1892                                   ;early method on an early gf.
1893
1894           (list class        ;A list to which real-make-a-method
1895                 qualifiers      ;can be applied to make a real method
1896                 arglist    ;corresponding to this early one.
1897                 unparsed
1898                 initargs
1899                 doc
1900                 slot-name))))
1901
1902 (defun real-make-a-method
1903        (class qualifiers lambda-list specializers initargs doc
1904         &optional slot-name)
1905   (setq specializers (parse-specializers specializers))
1906   (apply #'make-instance class
1907          :qualifiers qualifiers
1908          :lambda-list lambda-list
1909          :specializers specializers
1910          :documentation doc
1911          :slot-name slot-name
1912          :allow-other-keys t
1913          initargs))
1914
1915 (defun early-method-function (early-method)
1916   (values (cadr early-method) (caddr early-method)))
1917
1918 (defun early-method-class (early-method)
1919   (find-class (car (fifth early-method))))
1920
1921 (defun early-method-standard-accessor-p (early-method)
1922   (let ((class (first (fifth early-method))))
1923     (or (eq class 'standard-reader-method)
1924         (eq class 'standard-writer-method)
1925         (eq class 'standard-boundp-method))))
1926
1927 (defun early-method-standard-accessor-slot-name (early-method)
1928   (seventh (fifth early-method)))
1929
1930 ;;; Fetch the specializers of an early method. This is basically just
1931 ;;; a simple accessor except that when the second argument is t, this
1932 ;;; converts the specializers from symbols into class objects. The
1933 ;;; class objects are cached in the early method, this makes
1934 ;;; bootstrapping faster because the class objects only have to be
1935 ;;; computed once.
1936 ;;;
1937 ;;; NOTE:
1938 ;;;  The second argument should only be passed as T by
1939 ;;;  early-lookup-method. This is to implement the rule that only when
1940 ;;;  there is more than one early method on a generic function is the
1941 ;;;  conversion from class names to class objects done. This
1942 ;;;  corresponds to the fact that we are only allowed to have one
1943 ;;;  method on any generic function up until the time classes exist.
1944 (defun early-method-specializers (early-method &optional objectsp)
1945   (if (and (listp early-method)
1946            (eq (car early-method) :early-method))
1947       (cond ((eq objectsp t)
1948              (or (fourth early-method)
1949                  (setf (fourth early-method)
1950                        (mapcar #'find-class (cadddr (fifth early-method))))))
1951             (t
1952              (cadddr (fifth early-method))))
1953       (error "~S is not an early-method." early-method)))
1954
1955 (defun early-method-qualifiers (early-method)
1956   (cadr (fifth early-method)))
1957
1958 (defun early-method-lambda-list (early-method)
1959   (caddr (fifth early-method)))
1960
1961 (defun early-add-named-method (generic-function-name
1962                                qualifiers
1963                                specializers
1964                                arglist
1965                                &rest initargs)
1966   (let* ((gf (ensure-generic-function generic-function-name))
1967          (existing
1968            (dolist (m (early-gf-methods gf))
1969              (when (and (equal (early-method-specializers m) specializers)
1970                         (equal (early-method-qualifiers m) qualifiers))
1971                (return m))))
1972          (new (make-a-method 'standard-method
1973                              qualifiers
1974                              arglist
1975                              specializers
1976                              initargs
1977                              ())))
1978     (when existing (remove-method gf existing))
1979     (add-method gf new)))
1980
1981 ;;; This is the early version of ADD-METHOD. Later this will become a
1982 ;;; generic function. See !FIX-EARLY-GENERIC-FUNCTIONS which has
1983 ;;; special knowledge about ADD-METHOD.
1984 (defun add-method (generic-function method)
1985   (when (not (fsc-instance-p generic-function))
1986     (error "Early ADD-METHOD didn't get a funcallable instance."))
1987   (when (not (and (listp method) (eq (car method) :early-method)))
1988     (error "Early ADD-METHOD didn't get an early method."))
1989   (push method (early-gf-methods generic-function))
1990   (set-arg-info generic-function :new-method method)
1991   (unless (assoc (!early-gf-name generic-function)
1992                  *!generic-function-fixups*
1993                  :test #'equal)
1994     (update-dfun generic-function)))
1995
1996 ;;; This is the early version of REMOVE-METHOD. See comments on
1997 ;;; the early version of ADD-METHOD.
1998 (defun remove-method (generic-function method)
1999   (when (not (fsc-instance-p generic-function))
2000     (error "An early remove-method didn't get a funcallable instance."))
2001   (when (not (and (listp method) (eq (car method) :early-method)))
2002     (error "An early remove-method didn't get an early method."))
2003   (setf (early-gf-methods generic-function)
2004         (remove method (early-gf-methods generic-function)))
2005   (set-arg-info generic-function)
2006   (unless (assoc (!early-gf-name generic-function)
2007                  *!generic-function-fixups*
2008                  :test #'equal)
2009     (update-dfun generic-function)))
2010
2011 ;;; This is the early version of GET-METHOD. See comments on the early
2012 ;;; version of ADD-METHOD.
2013 (defun get-method (generic-function qualifiers specializers
2014                                     &optional (errorp t))
2015   (if (early-gf-p generic-function)
2016       (or (dolist (m (early-gf-methods generic-function))
2017             (when (and (or (equal (early-method-specializers m nil)
2018                                   specializers)
2019                            (equal (early-method-specializers m t)
2020                                   specializers))
2021                        (equal (early-method-qualifiers m) qualifiers))
2022               (return m)))
2023           (if errorp
2024               (error "can't get early method")
2025               nil))
2026       (real-get-method generic-function qualifiers specializers errorp)))
2027
2028 (defun !fix-early-generic-functions ()
2029   (let ((accessors nil))
2030     ;; Rearrange *!EARLY-GENERIC-FUNCTIONS* to speed up
2031     ;; FIX-EARLY-GENERIC-FUNCTIONS.
2032     (dolist (early-gf-spec *!early-generic-functions*)
2033       (when (every #'early-method-standard-accessor-p
2034                    (early-gf-methods (gdefinition early-gf-spec)))
2035         (push early-gf-spec accessors)))
2036     (dolist (spec (nconc accessors
2037                          '(accessor-method-slot-name
2038                            generic-function-methods
2039                            method-specializers
2040                            specializerp
2041                            specializer-type
2042                            specializer-class
2043                            slot-definition-location
2044                            slot-definition-name
2045                            class-slots
2046                            gf-arg-info
2047                            class-precedence-list
2048                            slot-boundp-using-class
2049                            (setf slot-value-using-class)
2050                            slot-value-using-class
2051                            structure-class-p
2052                            standard-class-p
2053                            funcallable-standard-class-p
2054                            specializerp)))
2055       (/show spec)
2056       (setq *!early-generic-functions*
2057             (cons spec
2058                   (delete spec *!early-generic-functions* :test #'equal))))
2059
2060     (dolist (early-gf-spec *!early-generic-functions*)
2061       (/show early-gf-spec)
2062       (let* ((gf (gdefinition early-gf-spec))
2063              (methods (mapcar (lambda (early-method)
2064                                 (let ((args (copy-list (fifth
2065                                                         early-method))))
2066                                   (setf (fourth args)
2067                                         (early-method-specializers
2068                                          early-method t))
2069                                   (apply #'real-make-a-method args)))
2070                               (early-gf-methods gf))))
2071         (setf (generic-function-method-class gf) *the-class-standard-method*)
2072         (setf (generic-function-method-combination gf)
2073               *standard-method-combination*)
2074         (set-methods gf methods)))
2075
2076     (dolist (fn *!early-functions*)
2077       (/show fn)
2078       (setf (gdefinition (car fn)) (fdefinition (caddr fn))))
2079
2080     (dolist (fixup *!generic-function-fixups*)
2081       (/show fixup)
2082       (let* ((fspec (car fixup))
2083              (gf (gdefinition fspec))
2084              (methods (mapcar (lambda (method)
2085                                 (let* ((lambda-list (first method))
2086                                        (specializers (second method))
2087                                        (method-fn-name (third method))
2088                                        (fn-name (or method-fn-name fspec))
2089                                        (fn (fdefinition fn-name))
2090                                        (initargs
2091                                         (list :function
2092                                               (set-fun-name
2093                                                (lambda (args next-methods)
2094                                                  (declare (ignore
2095                                                            next-methods))
2096                                                  (apply fn args))
2097                                                `(call ,fn-name)))))
2098                                   (declare (type function fn))
2099                                   (make-a-method 'standard-method
2100                                                  ()
2101                                                  lambda-list
2102                                                  specializers
2103                                                  initargs
2104                                                  nil)))
2105                               (cdr fixup))))
2106         (setf (generic-function-method-class gf) *the-class-standard-method*)
2107         (setf (generic-function-method-combination gf)
2108               *standard-method-combination*)
2109         (set-methods gf methods))))
2110   (/show "leaving !FIX-EARLY-GENERIC-FUNCTIONS"))
2111 \f
2112 ;;; PARSE-DEFMETHOD is used by DEFMETHOD to parse the &REST argument
2113 ;;; into the 'real' arguments. This is where the syntax of DEFMETHOD
2114 ;;; is really implemented.
2115 (defun parse-defmethod (cdr-of-form)
2116   (declare (list cdr-of-form))
2117   (let ((name (pop cdr-of-form))
2118         (qualifiers ())
2119         (spec-ll ()))
2120     (loop (if (and (car cdr-of-form) (atom (car cdr-of-form)))
2121               (push (pop cdr-of-form) qualifiers)
2122               (return (setq qualifiers (nreverse qualifiers)))))
2123     (setq spec-ll (pop cdr-of-form))
2124     (values name qualifiers spec-ll cdr-of-form)))
2125
2126 (defun parse-specializers (specializers)
2127   (declare (list specializers))
2128   (flet ((parse (spec)
2129            (let ((result (specializer-from-type spec)))
2130              (if (specializerp result)
2131                  result
2132                  (if (symbolp spec)
2133                      (error "~S was used as a specializer,~%~
2134                              but is not the name of a class."
2135                             spec)
2136                      (error "~S is not a legal specializer." spec))))))
2137     (mapcar #'parse specializers)))
2138
2139 (defun unparse-specializers (specializers-or-method)
2140   (if (listp specializers-or-method)
2141       (flet ((unparse (spec)
2142                (if (specializerp spec)
2143                    (let ((type (specializer-type spec)))
2144                      (if (and (consp type)
2145                               (eq (car type) 'class))
2146                          (let* ((class (cadr type))
2147                                 (class-name (class-name class)))
2148                            (if (eq class (find-class class-name nil))
2149                                class-name
2150                                type))
2151                          type))
2152                    (error "~S is not a legal specializer." spec))))
2153         (mapcar #'unparse specializers-or-method))
2154       (unparse-specializers (method-specializers specializers-or-method))))
2155
2156 (defun parse-method-or-spec (spec &optional (errorp t))
2157   (let (gf method name temp)
2158     (if (method-p spec)
2159         (setq method spec
2160               gf (method-generic-function method)
2161               temp (and gf (generic-function-name gf))
2162               name (if temp
2163                        (intern-fun-name
2164                          (make-method-spec temp
2165                                            (method-qualifiers method)
2166                                            (unparse-specializers
2167                                              (method-specializers method))))
2168                        (make-symbol (format nil "~S" method))))
2169         (multiple-value-bind (gf-spec quals specls)
2170             (parse-defmethod spec)
2171           (and (setq gf (and (or errorp (gboundp gf-spec))
2172                              (gdefinition gf-spec)))
2173                (let ((nreq (compute-discriminating-function-arglist-info gf)))
2174                  (setq specls (append (parse-specializers specls)
2175                                       (make-list (- nreq (length specls))
2176                                                  :initial-element
2177                                                  *the-class-t*)))
2178                  (and
2179                    (setq method (get-method gf quals specls errorp))
2180                    (setq name
2181                          (intern-fun-name (make-method-spec gf-spec
2182                                                             quals
2183                                                             specls))))))))
2184     (values gf method name)))
2185 \f
2186 (defun extract-parameters (specialized-lambda-list)
2187   (multiple-value-bind (parameters ignore1 ignore2)
2188       (parse-specialized-lambda-list specialized-lambda-list)
2189     (declare (ignore ignore1 ignore2))
2190     parameters))
2191
2192 (defun extract-lambda-list (specialized-lambda-list)
2193   (multiple-value-bind (ignore1 lambda-list ignore2)
2194       (parse-specialized-lambda-list specialized-lambda-list)
2195     (declare (ignore ignore1 ignore2))
2196     lambda-list))
2197
2198 (defun extract-specializer-names (specialized-lambda-list)
2199   (multiple-value-bind (ignore1 ignore2 specializers)
2200       (parse-specialized-lambda-list specialized-lambda-list)
2201     (declare (ignore ignore1 ignore2))
2202     specializers))
2203
2204 (defun extract-required-parameters (specialized-lambda-list)
2205   (multiple-value-bind (ignore1 ignore2 ignore3 required-parameters)
2206       (parse-specialized-lambda-list specialized-lambda-list)
2207     (declare (ignore ignore1 ignore2 ignore3))
2208     required-parameters))
2209
2210 (defun parse-specialized-lambda-list (arglist &optional post-keyword)
2211   ;;(declare (values parameters lambda-list specializers required-parameters))
2212   (let ((arg (car arglist)))
2213     (cond ((null arglist) (values nil nil nil nil))
2214           ((eq arg '&aux)
2215            (values nil arglist nil))
2216           ((memq arg lambda-list-keywords)
2217            (unless (memq arg '(&optional &rest &key &allow-other-keys &aux))
2218              ;; Now, since we try to conform to ANSI, non-standard
2219              ;; lambda-list-keywords should be treated as errors.
2220              (error 'simple-program-error
2221                     :format-control "unrecognized lambda-list keyword ~S ~
2222                      in arglist.~%"
2223                     :format-arguments (list arg)))
2224            ;; When we are at a lambda-list keyword, the parameters
2225            ;; don't include the lambda-list keyword; the lambda-list
2226            ;; does include the lambda-list keyword; and no
2227            ;; specializers are allowed to follow the lambda-list
2228            ;; keywords (at least for now).
2229            (multiple-value-bind (parameters lambda-list)
2230                (parse-specialized-lambda-list (cdr arglist) t)
2231              (when (eq arg '&rest)
2232                ;; check, if &rest is followed by a var ...
2233                (when (or (null lambda-list)
2234                          (memq (car lambda-list) lambda-list-keywords))
2235                  (error "Error in lambda-list:~%~
2236                          After &REST, a DEFMETHOD lambda-list ~
2237                          must be followed by at least one variable.")))
2238              (values parameters
2239                      (cons arg lambda-list)
2240                      ()
2241                      ())))
2242           (post-keyword
2243            ;; After a lambda-list keyword there can be no specializers.
2244            (multiple-value-bind (parameters lambda-list)
2245                (parse-specialized-lambda-list (cdr arglist) t)
2246              (values (cons (if (listp arg) (car arg) arg) parameters)
2247                      (cons arg lambda-list)
2248                      ()
2249                      ())))
2250           (t
2251            (multiple-value-bind (parameters lambda-list specializers required)
2252                (parse-specialized-lambda-list (cdr arglist))
2253              (values (cons (if (listp arg) (car arg) arg) parameters)
2254                      (cons (if (listp arg) (car arg) arg) lambda-list)
2255                      (cons (if (listp arg) (cadr arg) t) specializers)
2256                      (cons (if (listp arg) (car arg) arg) required)))))))
2257 \f
2258 (setq *boot-state* 'early)
2259 \f
2260 ;;; FIXME: In here there was a #-CMU definition of SYMBOL-MACROLET
2261 ;;; which used %WALKER stuff. That suggests to me that maybe the code
2262 ;;; walker stuff was only used for implementing stuff like that; maybe
2263 ;;; it's not needed any more? Hunt down what it was used for and see.
2264
2265 (defmacro with-slots (slots instance &body body)
2266   (let ((in (gensym)))
2267     `(let ((,in ,instance))
2268        (declare (ignorable ,in))
2269        ,@(let ((instance (if (and (consp instance) (eq (car instance) 'the))
2270                              (third instance)
2271                              instance)))
2272            (and (symbolp instance)
2273                 `((declare (%variable-rebinding ,in ,instance)))))
2274        ,in
2275        (symbol-macrolet ,(mapcar (lambda (slot-entry)
2276                                    (let ((var-name
2277                                           (if (symbolp slot-entry)
2278                                               slot-entry
2279                                               (car slot-entry)))
2280                                          (slot-name
2281                                           (if (symbolp slot-entry)
2282                                               slot-entry
2283                                               (cadr slot-entry))))
2284                                      `(,var-name
2285                                        (slot-value ,in ',slot-name))))
2286                                  slots)
2287                         ,@body))))
2288
2289 (defmacro with-accessors (slots instance &body body)
2290   (let ((in (gensym)))
2291     `(let ((,in ,instance))
2292        (declare (ignorable ,in))
2293        ,@(let ((instance (if (and (consp instance) (eq (car instance) 'the))
2294                              (third instance)
2295                              instance)))
2296            (and (symbolp instance)
2297                 `((declare (%variable-rebinding ,in ,instance)))))
2298        ,in
2299        (symbol-macrolet ,(mapcar (lambda (slot-entry)
2300                                    (let ((var-name (car slot-entry))
2301                                          (accessor-name (cadr slot-entry)))
2302                                      `(,var-name (,accessor-name ,in))))
2303                                  slots)
2304           ,@body))))