0.9.2.45:

[sbcl/lichteblau.git] / src / pcl / braid.lisp

;;;; bootstrapping the meta-braid
;;;;
;;;; The code in this file takes the early definitions that have been
;;;; saved up and actually builds those class objects. This work is
;;;; largely driven off of those class definitions, but the fact that
;;;; STANDARD-CLASS is the class of all metaclasses in the braid is
;;;; built into this code pretty deeply.

;;;; This software is part of the SBCL system. See the README file for
;;;; more information.

;;;; This software is derived from software originally released by Xerox
;;;; Corporation. Copyright and release statements follow. Later modifications
;;;; to the software are in the public domain and are provided with
;;;; absolutely no warranty. See the COPYING and CREDITS files for more
;;;; information.

;;;; copyright information from original PCL sources:
;;;;
;;;; Copyright (c) 1985, 1986, 1987, 1988, 1989, 1990 Xerox Corporation.
;;;; All rights reserved.
;;;;
;;;; Use and copying of this software and preparation of derivative works based
;;;; upon this software are permitted. Any distribution of this software or
;;;; derivative works must comply with all applicable United States export
;;;; control laws.
;;;;
;;;; This software is made available AS IS, and Xerox Corporation makes no
;;;; warranty about the software, its performance or its conformity to any
;;;; specification.

(in-package "SB-PCL")
\f
(defun allocate-standard-instance (wrapper
                                   &optional (slots-init nil slots-init-p))
  (let ((instance (%make-standard-instance nil (get-instance-hash-code)))
        (no-of-slots (wrapper-no-of-instance-slots wrapper)))
    (setf (std-instance-wrapper instance) wrapper)
    (setf (std-instance-slots instance)
          (cond (slots-init-p
                 ;; Inline the slots vector allocation and initialization.
                 (let ((slots (make-array no-of-slots :initial-element 0)))
                   (do ((rem-slots slots-init (rest rem-slots))
                        (i 0 (1+ i)))
                       ((>= i no-of-slots)) ;endp rem-slots))
                     (declare (list rem-slots)
                              (type index i))
                     (setf (aref slots i) (first rem-slots)))
                   slots))
                (t
                 (make-array no-of-slots
                             :initial-element +slot-unbound+))))
    instance))

(defmacro allocate-funcallable-instance-slots (wrapper &optional
                                                       slots-init-p slots-init)
  `(let ((no-of-slots (wrapper-no-of-instance-slots ,wrapper)))
     ,(if slots-init-p
          `(if ,slots-init-p
               (make-array no-of-slots :initial-contents ,slots-init)
               (make-array no-of-slots :initial-element +slot-unbound+))
          `(make-array no-of-slots :initial-element +slot-unbound+))))

(defun allocate-funcallable-instance (wrapper &optional
                                              (slots-init nil slots-init-p))
  (let ((fin (%make-pcl-funcallable-instance nil nil
                                             (get-instance-hash-code))))
    (set-funcallable-instance-function
     fin
     #'(instance-lambda (&rest args)
         (declare (ignore args))
         (error "The function of the funcallable-instance ~S has not been set."
                fin)))
    (setf (fsc-instance-wrapper fin) wrapper
          (fsc-instance-slots fin) (allocate-funcallable-instance-slots
                                    wrapper slots-init-p slots-init))
    fin))

(defun allocate-structure-instance (wrapper &optional
                                            (slots-init nil slots-init-p))
  (let* ((class (wrapper-class wrapper))
         (constructor (class-defstruct-constructor class)))
    (if constructor
        (let ((instance (funcall constructor))
              (slots (class-slots class)))
          (when slots-init-p
            (dolist (slot slots)
              (setf (slot-value-using-class class instance slot)
                    (pop slots-init))))
          instance)
        (error "can't allocate an instance of class ~S" (class-name class)))))
\f
;;;; BOOTSTRAP-META-BRAID
;;;;
;;;; This function builds the base metabraid from the early class definitions.

(defmacro !initial-classes-and-wrappers (&rest classes)
  `(progn
     ,@(mapcar (lambda (class)
                 (let ((wr (format-symbol *pcl-package* "~A-WRAPPER" class)))
                   `(setf ,wr ,(if (eq class 'standard-generic-function)
                                   '*sgf-wrapper*
                                   `(boot-make-wrapper
                                     (early-class-size ',class)
                                     ',class))
                          ,class (allocate-standard-instance
                                  ,(if (eq class 'standard-generic-function)
                                       'funcallable-standard-class-wrapper
                                       'standard-class-wrapper))
                          (wrapper-class ,wr) ,class
                          (find-class ',class) ,class)))
               classes)))

(defun !bootstrap-meta-braid ()
  (let* ((*create-classes-from-internal-structure-definitions-p* nil)
         std-class-wrapper std-class
         standard-class-wrapper standard-class
         funcallable-standard-class-wrapper funcallable-standard-class
         slot-class-wrapper slot-class
         built-in-class-wrapper built-in-class
         structure-class-wrapper structure-class
         condition-class-wrapper condition-class
         standard-direct-slot-definition-wrapper
         standard-direct-slot-definition
         standard-effective-slot-definition-wrapper
         standard-effective-slot-definition
         class-eq-specializer-wrapper class-eq-specializer
         standard-generic-function-wrapper standard-generic-function)
    (!initial-classes-and-wrappers
     standard-class funcallable-standard-class
     slot-class built-in-class structure-class condition-class std-class
     standard-direct-slot-definition standard-effective-slot-definition
     class-eq-specializer standard-generic-function)
    ;; First, make a class metaobject for each of the early classes. For
    ;; each metaobject we also set its wrapper. Except for the class T,
    ;; the wrapper is always that of STANDARD-CLASS.
    (dolist (definition *early-class-definitions*)
      (let* ((name (ecd-class-name definition))
             (meta (ecd-metaclass definition))
             (wrapper (ecase meta
                        (slot-class slot-class-wrapper)
                        (std-class std-class-wrapper)
                        (standard-class standard-class-wrapper)
                        (funcallable-standard-class
                         funcallable-standard-class-wrapper)
                        (built-in-class built-in-class-wrapper)
                        (structure-class structure-class-wrapper)
                        (condition-class condition-class-wrapper)))
             (class (or (find-class name nil)
                        (allocate-standard-instance wrapper))))
        (setf (find-class name) class)))
    (dolist (definition *early-class-definitions*)
      (let ((name (ecd-class-name definition))
            (meta (ecd-metaclass definition))
            (source (ecd-source definition))
            (direct-supers (ecd-superclass-names definition))
            (direct-slots  (ecd-canonical-slots definition))
            (other-initargs (ecd-other-initargs definition)))
        (let ((direct-default-initargs
               (getf other-initargs :direct-default-initargs)))
          (multiple-value-bind (slots cpl default-initargs direct-subclasses)
              (early-collect-inheritance name)
            (let* ((class (find-class name))
                   (wrapper (cond ((eq class slot-class)
                                   slot-class-wrapper)
                                  ((eq class std-class)
                                   std-class-wrapper)
                                  ((eq class standard-class)
                                   standard-class-wrapper)
                                  ((eq class funcallable-standard-class)
                                   funcallable-standard-class-wrapper)
                                  ((eq class standard-direct-slot-definition)
                                   standard-direct-slot-definition-wrapper)
                                  ((eq class
                                       standard-effective-slot-definition)
                                   standard-effective-slot-definition-wrapper)
                                  ((eq class built-in-class)
                                   built-in-class-wrapper)
                                  ((eq class structure-class)
                                   structure-class-wrapper)
                                  ((eq class condition-class)
                                   condition-class-wrapper)
                                  ((eq class class-eq-specializer)
                                   class-eq-specializer-wrapper)
                                  ((eq class standard-generic-function)
                                   standard-generic-function-wrapper)
                                  (t
                                   (boot-make-wrapper (length slots) name))))
                   (proto nil))
              (when (eq name t) (setq *the-wrapper-of-t* wrapper))
              (set (make-class-symbol name) class)
              (dolist (slot slots)
                (unless (eq (getf slot :allocation :instance) :instance)
                  (error "Slot allocation ~S is not supported in bootstrap."
                         (getf slot :allocation))))

              (when (typep wrapper 'wrapper)
                (setf (wrapper-instance-slots-layout wrapper)
                      (mapcar #'canonical-slot-name slots))
                (setf (wrapper-class-slots wrapper)
                      ()))

              (setq proto (if (eq meta 'funcallable-standard-class)
                              (allocate-funcallable-instance wrapper)
                              (allocate-standard-instance wrapper)))

              (setq direct-slots
                    (!bootstrap-make-slot-definitions
                     name class direct-slots
                     standard-direct-slot-definition-wrapper nil))
              (setq slots
                    (!bootstrap-make-slot-definitions
                     name class slots
                     standard-effective-slot-definition-wrapper t))

              (case meta
                ((std-class standard-class funcallable-standard-class)
                 (!bootstrap-initialize-class
                  meta
                  class name class-eq-specializer-wrapper source
                  direct-supers direct-subclasses cpl wrapper proto
                  direct-slots slots direct-default-initargs default-initargs))
                (built-in-class         ; *the-class-t*
                 (!bootstrap-initialize-class
                  meta
                  class name class-eq-specializer-wrapper source
                  direct-supers direct-subclasses cpl wrapper proto))
                (slot-class             ; *the-class-slot-object*
                 (!bootstrap-initialize-class
                  meta
                  class name class-eq-specializer-wrapper source
                  direct-supers direct-subclasses cpl wrapper proto))
                (structure-class        ; *the-class-structure-object*
                 (!bootstrap-initialize-class
                  meta
                  class name class-eq-specializer-wrapper source
                  direct-supers direct-subclasses cpl wrapper))
                (condition-class
                 (!bootstrap-initialize-class
                  meta
                  class name class-eq-specializer-wrapper source
                  direct-supers direct-subclasses cpl wrapper))))))))

    (let* ((smc-class (find-class 'standard-method-combination))
           (smc-wrapper (!bootstrap-get-slot 'standard-class
                                             smc-class
                                             'wrapper))
           (smc (allocate-standard-instance smc-wrapper)))
      (flet ((set-slot (name value)
               (!bootstrap-set-slot 'standard-method-combination
                                    smc
                                    name
                                    value)))
        (set-slot 'source *load-pathname*)
        (set-slot 'type 'standard)
        (set-slot 'documentation "The standard method combination.")
        (set-slot 'options ()))
      (setq *standard-method-combination* smc))))

;;; Initialize a class metaobject.
(defun !bootstrap-initialize-class
       (metaclass-name class name
        class-eq-wrapper source direct-supers direct-subclasses cpl wrapper
        &optional
        (proto nil proto-p)
        direct-slots slots direct-default-initargs default-initargs)
  (flet ((classes (names) (mapcar #'find-class names))
         (set-slot (slot-name value)
           (!bootstrap-set-slot metaclass-name class slot-name value)))
    (set-slot 'name name)
    (set-slot 'finalized-p t)
    (set-slot 'source source)
    (set-slot 'type (if (eq class (find-class t))
                        t
                        ;; FIXME: Could this just be CLASS instead
                        ;; of `(CLASS ,CLASS)? If not, why not?
                        ;; (See also similar expression in 
                        ;; SHARED-INITIALIZE :BEFORE (CLASS).)
                        `(class ,class)))
    (set-slot 'class-eq-specializer
              (let ((spec (allocate-standard-instance class-eq-wrapper)))
                (!bootstrap-set-slot 'class-eq-specializer spec 'type
                                     `(class-eq ,class))
                (!bootstrap-set-slot 'class-eq-specializer spec 'object
                                     class)
                spec))
    (set-slot 'class-precedence-list (classes cpl))
    (set-slot 'cpl-available-p t)
    (set-slot 'can-precede-list (classes (cdr cpl)))
    (set-slot 'incompatible-superclass-list nil)
    (set-slot 'direct-superclasses (classes direct-supers))
    (set-slot 'direct-subclasses (classes direct-subclasses))
    (set-slot 'direct-methods (cons nil nil))
    (set-slot 'wrapper wrapper)
    (set-slot 'predicate-name (or (cadr (assoc name *early-class-predicates*))
                                  (make-class-predicate-name name)))
    (set-slot 'documentation nil)
    (set-slot 'plist
              `(,@(and direct-default-initargs
                       `(direct-default-initargs ,direct-default-initargs))
                ,@(and default-initargs
                       `(default-initargs ,default-initargs))))
    (when (memq metaclass-name '(standard-class funcallable-standard-class
                                 structure-class condition-class
                                 slot-class std-class))
      (set-slot 'direct-slots direct-slots)
      (set-slot 'slots slots))

    ;; For all direct superclasses SUPER of CLASS, make sure CLASS is
    ;; a direct subclass of SUPER.  Note that METACLASS-NAME doesn't
    ;; matter here for the slot DIRECT-SUBCLASSES, since every class
    ;; inherits the slot from class CLASS.
    (dolist (super direct-supers)
      (let* ((super (find-class super))
             (subclasses (!bootstrap-get-slot metaclass-name super
                                              'direct-subclasses)))
        (cond ((eq +slot-unbound+ subclasses)
               (!bootstrap-set-slot metaclass-name super 'direct-subclasses
                                    (list class)))
              ((not (memq class subclasses))
               (!bootstrap-set-slot metaclass-name super 'direct-subclasses
                                    (cons class subclasses))))))

    (case metaclass-name
      (structure-class
       (let ((constructor-sym '|STRUCTURE-OBJECT class constructor|))
         (set-slot 'predicate-name (or (cadr (assoc name
                                                    *early-class-predicates*))
                                       (make-class-predicate-name name)))
         (set-slot 'defstruct-form
                   `(defstruct (structure-object (:constructor
                                                  ,constructor-sym)
                                                 (:copier nil))))
         (set-slot 'defstruct-constructor constructor-sym)
         (set-slot 'from-defclass-p t)
         (set-slot 'plist nil)
         (set-slot 'prototype (funcall constructor-sym))))
      (condition-class
       (set-slot 'prototype (make-condition name)))
      (t
       (set-slot 'prototype
                 (if proto-p proto (allocate-standard-instance wrapper)))))
    class))

(defun !bootstrap-make-slot-definitions (name class slots wrapper effective-p)
  (let ((index -1))
    (mapcar (lambda (slot)
              (incf index)
              (!bootstrap-make-slot-definition
               name class slot wrapper effective-p index))
            slots)))

(defun !bootstrap-make-slot-definition
    (name class slot wrapper effective-p index)
  (let* ((slotd-class-name (if effective-p
                               'standard-effective-slot-definition
                               'standard-direct-slot-definition))
         (slotd (allocate-standard-instance wrapper))
         (slot-name (getf slot :name)))
    (flet ((get-val (name) (getf slot name))
           (set-val (name val)
                    (!bootstrap-set-slot slotd-class-name slotd name val)))
      (set-val 'name         slot-name)
      (set-val 'initform     (get-val :initform))
      (set-val 'initfunction (get-val :initfunction))
      (set-val 'initargs     (get-val :initargs))
      (set-val 'readers      (get-val :readers))
      (set-val 'writers      (get-val :writers))
      (set-val 'allocation   :instance)
      (set-val 'type         (or (get-val :type) t))
      (set-val 'documentation (or (get-val :documentation) ""))
      (set-val 'class   class)
      (when effective-p
        (set-val 'location index)
        (let ((fsc-p nil))
          (set-val 'reader-function (make-optimized-std-reader-method-function
                                     fsc-p nil slot-name index))
          (set-val 'writer-function (make-optimized-std-writer-method-function
                                     fsc-p nil slot-name index))
          (set-val 'boundp-function (make-optimized-std-boundp-method-function
                                     fsc-p nil slot-name index)))
        (set-val 'accessor-flags 7)
        (let ((table (or (gethash slot-name *name->class->slotd-table*)
                         (setf (gethash slot-name *name->class->slotd-table*)
                               (make-hash-table :test 'eq :size 5)))))
          (setf (gethash class table) slotd)))
      (when (and (eq name 'standard-class)
                 (eq slot-name 'slots) effective-p)
        (setq *the-eslotd-standard-class-slots* slotd))
      (when (and (eq name 'funcallable-standard-class)
                 (eq slot-name 'slots) effective-p)
        (setq *the-eslotd-funcallable-standard-class-slots* slotd))
      slotd)))

(defun !bootstrap-accessor-definitions (early-p)
  (let ((*early-p* early-p))
    (dolist (definition *early-class-definitions*)
      (let ((name (ecd-class-name definition))
            (meta (ecd-metaclass definition)))
        (unless (eq meta 'built-in-class)
          (let ((direct-slots  (ecd-canonical-slots definition)))
            (dolist (slotd direct-slots)
              (let ((slot-name (getf slotd :name))
                    (readers (getf slotd :readers))
                    (writers (getf slotd :writers)))
                (!bootstrap-accessor-definitions1
                 name
                 slot-name
                 readers
                 writers
                 nil)
                (!bootstrap-accessor-definitions1
                 'slot-object
                 slot-name
                 (list (slot-reader-name slot-name))
                 (list (slot-writer-name slot-name))
                 (list (slot-boundp-name slot-name)))))))))))

(defun !bootstrap-accessor-definition (class-name accessor-name slot-name type)
  (multiple-value-bind (accessor-class make-method-function arglist specls doc)
      (ecase type
        (reader (values 'standard-reader-method
                        #'make-std-reader-method-function
                        (list class-name)
                        (list class-name)
                        "automatically generated reader method"))
        (writer (values 'standard-writer-method
                        #'make-std-writer-method-function
                        (list 'new-value class-name)
                        (list t class-name)
                        "automatically generated writer method"))
        (boundp (values 'standard-boundp-method
                        #'make-std-boundp-method-function
                        (list class-name)
                        (list class-name)
                        "automatically generated boundp method")))
    (let ((gf (ensure-generic-function accessor-name
                                       :lambda-list arglist)))
      (if (find specls (early-gf-methods gf)
                :key #'early-method-specializers
                :test 'equal)
          (unless (assoc accessor-name *!generic-function-fixups*
                         :test #'equal)
            (update-dfun gf))
          (add-method gf
                      (make-a-method accessor-class
                                     ()
                                     arglist specls
                                     (funcall make-method-function
                                              class-name slot-name)
                                     doc
                                     slot-name))))))

(defun !bootstrap-accessor-definitions1 (class-name
                                        slot-name
                                        readers
                                        writers
                                        boundps)
  (flet ((do-reader-definition (reader)
           (!bootstrap-accessor-definition class-name
                                           reader
                                           slot-name
                                           'reader))
         (do-writer-definition (writer)
           (!bootstrap-accessor-definition class-name
                                           writer
                                           slot-name
                                           'writer))
         (do-boundp-definition (boundp)
           (!bootstrap-accessor-definition class-name
                                           boundp
                                           slot-name
                                           'boundp)))
    (dolist (reader readers) (do-reader-definition reader))
    (dolist (writer writers) (do-writer-definition writer))
    (dolist (boundp boundps) (do-boundp-definition boundp))))

(defun !bootstrap-class-predicates (early-p)
  (let ((*early-p* early-p))
    (dolist (definition *early-class-definitions*)
      (let* ((name (ecd-class-name definition))
             (class (find-class name)))
        (setf (find-class-predicate name)
              (make-class-predicate class (class-predicate-name class)))))))

(defun !bootstrap-built-in-classes ()

  ;; First make sure that all the supers listed in
  ;; *BUILT-IN-CLASS-LATTICE* are themselves defined by
  ;; *BUILT-IN-CLASS-LATTICE*. This is just to check for typos and
  ;; other sorts of brainos.
  (dolist (e *built-in-classes*)
    (dolist (super (cadr e))
      (unless (or (eq super t)
                  (assq super *built-in-classes*))
        (error "in *BUILT-IN-CLASSES*: ~S has ~S as a super,~%~
                but ~S is not itself a class in *BUILT-IN-CLASSES*."
               (car e) super super))))

  ;; In the first pass, we create a skeletal object to be bound to the
  ;; class name.
  (let* ((built-in-class (find-class 'built-in-class))
         (built-in-class-wrapper (class-wrapper built-in-class)))
    (dolist (e *built-in-classes*)
      (let ((class (allocate-standard-instance built-in-class-wrapper)))
        (setf (find-class (car e)) class))))

  ;; In the second pass, we initialize the class objects.
  (let ((class-eq-wrapper (class-wrapper (find-class 'class-eq-specializer))))
    (dolist (e *built-in-classes*)
      (destructuring-bind (name supers subs cpl prototype) e
        (let* ((class (find-class name))
               (lclass (find-classoid name))
               (wrapper (classoid-layout lclass)))
          (set (get-built-in-class-symbol name) class)
          (set (get-built-in-wrapper-symbol name) wrapper)
          (setf (classoid-pcl-class lclass) class)

          (!bootstrap-initialize-class 'built-in-class class
                                       name class-eq-wrapper nil
                                       supers subs
                                       (cons name cpl)
                                       wrapper prototype)))))

  (dolist (e *built-in-classes*)
    (let* ((name (car e))
           (class (find-class name)))
      (setf (find-class-predicate name)
            (make-class-predicate class (class-predicate-name class))))))
\f
(defmacro wrapper-of-macro (x)
  `(layout-of ,x))

(defun class-of (x)
  (wrapper-class* (wrapper-of-macro x)))

;;; FIXME: We probably don't need both WRAPPER-OF and WRAPPER-OF-MACRO.
#-sb-fluid (declaim (inline wrapper-of))
(defun wrapper-of (x)
  (wrapper-of-macro x))

(defun eval-form (form)
  (lambda () (eval form)))

(defun ensure-non-standard-class (name &optional existing-class)
  (flet
      ((ensure (metaclass &optional (slots nil slotsp))
         (let ((supers
                (mapcar #'classoid-name (classoid-direct-superclasses
                                         (find-classoid name)))))
           (if slotsp
               (ensure-class-using-class existing-class name
                                         :metaclass metaclass :name name
                                         :direct-superclasses supers
                                         :direct-slots slots)
               (ensure-class-using-class existing-class name
                                         :metaclass metaclass :name name
                                         :direct-superclasses supers))))
       (slot-initargs-from-structure-slotd (slotd)
         (let ((accessor (structure-slotd-accessor-symbol slotd)))
           `(:name ,(structure-slotd-name slotd)
             :defstruct-accessor-symbol ,accessor
             ,@(when (fboundp accessor)
                 `(:internal-reader-function
                   ,(structure-slotd-reader-function slotd)
                   :internal-writer-function
                   ,(structure-slotd-writer-function name slotd)))
             :type ,(or (structure-slotd-type slotd) t)
             :initform ,(structure-slotd-init-form slotd)
             :initfunction ,(eval-form (structure-slotd-init-form slotd)))))
       (slot-initargs-from-condition-slot (slot)
         `(:name ,(condition-slot-name slot)
           :initargs ,(condition-slot-initargs slot)
           :readers ,(condition-slot-readers slot)
           :writers ,(condition-slot-writers slot)
           ,@(when (condition-slot-initform-p slot)
               (let ((form-or-fun (condition-slot-initform slot)))
                 (if (functionp form-or-fun)
                     `(:initfunction ,form-or-fun)
                     `(:initform ,form-or-fun
                       :initfunction ,(lambda () form-or-fun)))))
           :allocation ,(condition-slot-allocation slot)
           :documentation ,(condition-slot-documentation slot))))
    (cond ((structure-type-p name)
           (ensure 'structure-class
                   (mapcar #'slot-initargs-from-structure-slotd
                           (structure-type-slot-description-list name))))
          ((condition-type-p name)
           (ensure 'condition-class
                   (mapcar #'slot-initargs-from-condition-slot
                           (condition-classoid-slots (find-classoid name)))))
          (t
           (error "~@<~S is not the name of a class.~@:>" name)))))

(defun ensure-defstruct-class (classoid)
  (let ((class (classoid-pcl-class classoid)))
    (cond (class
           (ensure-non-standard-class (class-name class) class))
          ((eq 'complete *boot-state*) 
           (ensure-non-standard-class (classoid-name classoid))))))

(pushnew 'ensure-defstruct-class sb-kernel::*defstruct-hooks*)
\f
(defun make-class-predicate (class name)
  (let* ((gf (ensure-generic-function name :lambda-list '(object)))
         (mlist (if (eq *boot-state* 'complete)
                    (generic-function-methods gf)
                    (early-gf-methods gf))))
    (unless mlist
      (unless (eq class *the-class-t*)
        (let* ((default-method-function #'constantly-nil)
               (default-method-initargs (list :function
                                              default-method-function))
               (default-method (make-a-method
                                'standard-method
                                ()
                                (list 'object)
                                (list *the-class-t*)
                                default-method-initargs
                                "class predicate default method")))
          (setf (method-function-get default-method-function :constant-value)
                nil)
          (add-method gf default-method)))
      (let* ((class-method-function #'constantly-t)
             (class-method-initargs (list :function
                                          class-method-function))
             (class-method (make-a-method 'standard-method
                                          ()
                                          (list 'object)
                                          (list class)
                                          class-method-initargs
                                          "class predicate class method")))
        (setf (method-function-get class-method-function :constant-value) t)
        (add-method gf class-method)))
    gf))

;;; Set the inherits from CPL, and register the layout. This actually
;;; installs the class in the Lisp type system.
(defun update-lisp-class-layout (class layout)
  (let ((lclass (layout-classoid layout)))
    (unless (eq (classoid-layout lclass) layout)
      (setf (layout-inherits layout)
              (order-layout-inherits
               (map 'simple-vector #'class-wrapper
                    (reverse (rest (class-precedence-list class))))))
      (register-layout layout :invalidate t)

      ;; Subclasses of formerly forward-referenced-class may be
      ;; unknown to CL:FIND-CLASS and also anonymous. This
      ;; functionality moved here from (SETF FIND-CLASS).
      (let ((name (class-name class)))
        (setf (find-classoid name) lclass
              (classoid-name lclass) name)))))

(defun set-class-type-translation (class name)
  (let ((classoid (find-classoid name nil)))
    (etypecase classoid
      (null)
      (built-in-classoid
       (let ((translation (built-in-classoid-translation classoid)))
         (cond
           (translation
            (aver (ctype-p translation))
            (setf (info :type :translator class)
                  (lambda (spec) (declare (ignore spec)) translation)))
           (t
            (setf (info :type :translator class)
                  (lambda (spec) (declare (ignore spec)) classoid))))))
      (classoid
       (setf (info :type :translator class)
             (lambda (spec) (declare (ignore spec)) classoid))))))

(clrhash *find-class*)
(!bootstrap-meta-braid)
(!bootstrap-accessor-definitions t)
(!bootstrap-class-predicates t)
(!bootstrap-accessor-definitions nil)
(!bootstrap-class-predicates nil)
(!bootstrap-built-in-classes)

(dohash (name x *find-class*)
        (let* ((class (find-class-from-cell name x))
               (layout (class-wrapper class))
               (lclass (layout-classoid layout))
               (lclass-pcl-class (classoid-pcl-class lclass))
               (olclass (find-classoid name nil)))
          (if lclass-pcl-class
              (aver (eq class lclass-pcl-class))
              (setf (classoid-pcl-class lclass) class))

          (update-lisp-class-layout class layout)

          (cond (olclass
                 (aver (eq lclass olclass)))
                (t
                 (setf (find-classoid name) lclass)))

          (set-class-type-translation class name)))

(setq *boot-state* 'braid)

(defmethod no-applicable-method (generic-function &rest args)
  (error "~@<There is no applicable method for the generic function ~2I~_~S~
          ~I~_when called with arguments ~2I~_~S.~:>"
         generic-function
         args))

(defmethod no-next-method ((generic-function standard-generic-function)
                           (method standard-method) &rest args)
  (error "~@<There is no next method for the generic function ~2I~_~S~
          ~I~_when called from method ~2I~_~S~I~_with arguments ~2I~_~S.~:>"
         generic-function
         method
         args))

;;; An extension to the ANSI standard: in the presence of e.g. a
;;; :BEFORE method, it would seem that going through
;;; NO-APPLICABLE-METHOD is prohibited, as in fact there is an
;;; applicable method.  -- CSR, 2002-11-15
(defmethod no-primary-method (generic-function &rest args)
  (error "~@<There is no primary method for the generic function ~2I~_~S~
          ~I~_when called with arguments ~2I~_~S.~:>"
         generic-function
         args))

(defmethod invalid-qualifiers ((gf generic-function)
                               combin
                               method)
  (let ((qualifiers (method-qualifiers method)))
    (let ((why (cond
                 ((cdr qualifiers) "has too many qualifiers")
                 (t (aver (not (member (car qualifiers)
                                       '(:around :before :after))))
                    "has an invalid qualifier"))))
      (invalid-method-error
       method
       "The method ~S on ~S ~A.~%~
        Standard method combination requires all methods to have one~%~
        of the single qualifiers :AROUND, :BEFORE and :AFTER or to~%~
        have no qualifier at all."
       method gf why))))