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|
;;;-*-Mode:LISP; Package: PCL; Base:10; Syntax:Common-lisp -*-
;;;
;;; *************************************************************************
;;; 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.
;;;
;;; Any person obtaining a copy of this software is requested to send their
;;; name and post office or electronic mail address to:
;;; CommonLoops Coordinator
;;; Xerox PARC
;;; 3333 Coyote Hill Rd.
;;; Palo Alto, CA 94304
;;; (or send Arpanet mail to CommonLoops-Coordinator.pa@Xerox.arpa)
;;;
;;; Suggestions, comments and requests for improvements are also welcome.
;;; *************************************************************************
;;;
(in-package :pcl)
(defmethod wrapper-fetcher ((class standard-class))
'std-instance-wrapper)
(defmethod slots-fetcher ((class standard-class))
'std-instance-slots)
(defmethod raw-instance-allocator ((class standard-class))
'allocate-standard-instance)
;;;
;;; These four functions work on std-instances and fsc-instances. These are
;;; instances for which it is possible to change the wrapper and the slots.
;;;
;;; For these kinds of instances, most specified methods from the instance
;;; structure protocol are promoted to the implementation-specific class
;;; std-class. Many of these methods call these four functions.
;;;
(defun set-wrapper (inst new)
(cond ((std-instance-p inst)
#+new-kcl-wrapper
(set-structure-def inst new)
#-new-kcl-wrapper
(setf (std-instance-wrapper inst) new))
((fsc-instance-p inst)
(setf (fsc-instance-wrapper inst) new))
(t
(error "What kind of instance is this?"))))
#+ignore ; can't do this when using #+new-kcl-wrapper
(defun set-slots (inst new)
(cond ((std-instance-p inst)
(setf (std-instance-slots inst) new))
((fsc-instance-p inst)
(setf (fsc-instance-slots inst) new))
(t
(error "What kind of instance is this?"))))
(defun swap-wrappers-and-slots (i1 i2)
(without-interrupts
(cond ((std-instance-p i1)
#+new-kcl-wrapper
(swap-structure-contents i1 i2)
#-new-kcl-wrapper
(let ((w1 (std-instance-wrapper i1))
(s1 (std-instance-slots i1)))
(setf (std-instance-wrapper i1) (std-instance-wrapper i2))
(setf (std-instance-slots i1) (std-instance-slots i2))
(setf (std-instance-wrapper i2) w1)
(setf (std-instance-slots i2) s1)))
((fsc-instance-p i1)
(let ((w1 (fsc-instance-wrapper i1))
(s1 (fsc-instance-slots i1)))
(setf (fsc-instance-wrapper i1) (fsc-instance-wrapper i2))
(setf (fsc-instance-slots i1) (fsc-instance-slots i2))
(setf (fsc-instance-wrapper i2) w1)
(setf (fsc-instance-slots i2) s1)))
(t
(error "What kind of instance is this?")))))
(defun get-class-slot-value-1 (object wrapper slot-name)
(let ((entry (assoc slot-name (wrapper-class-slots wrapper))))
(if (null entry)
(slot-missing (wrapper-class wrapper) object slot-name 'slot-value)
(if (eq (cdr entry) *slot-unbound*)
(slot-unbound (wrapper-class wrapper) object slot-name)
(cdr entry)))))
(defun set-class-slot-value-1 (new-value object wrapper slot-name)
(let ((entry (assoc slot-name (wrapper-class-slots wrapper))))
(if (null entry)
(slot-missing (wrapper-class wrapper)
object
slot-name
'setf
new-value)
(setf (cdr entry) new-value))))
(defmethod class-slot-value ((class std-class) slot-name)
(let ((wrapper (class-wrapper class))
(prototype (class-prototype class)))
(get-class-slot-value-1 prototype wrapper slot-name)))
(defmethod (setf class-slot-value) (nv (class std-class) slot-name)
(let ((wrapper (class-wrapper class))
(prototype (class-prototype class)))
(set-class-slot-value-1 nv prototype wrapper slot-name)))
(defun find-slot-definition (class slot-name)
(dolist (slot (class-slots class) nil)
(when (eql slot-name (slot-definition-name slot))
(return slot))))
(defun slot-value (object slot-name)
(let* ((class (class-of object))
(slot-definition (find-slot-definition class slot-name)))
(if (null slot-definition)
(slot-missing class object slot-name 'slot-value)
(slot-value-using-class class object slot-definition))))
(setf (gdefinition 'slot-value-normal) #'slot-value)
(define-compiler-macro slot-value (object-form slot-name-form)
(if (and (constantp slot-name-form)
(let ((slot-name (eval slot-name-form)))
(and (symbolp slot-name) (symbol-package slot-name))))
`(accessor-slot-value ,object-form ,slot-name-form)
`(slot-value-normal ,object-form ,slot-name-form)))
(defun set-slot-value (object slot-name new-value)
(let* ((class (class-of object))
(slot-definition (find-slot-definition class slot-name)))
(if (null slot-definition)
(slot-missing class object slot-name 'setf)
(setf (slot-value-using-class class object slot-definition)
new-value))))
(setf (gdefinition 'set-slot-value-normal) #'set-slot-value)
(define-compiler-macro set-slot-value (object-form slot-name-form new-value-form)
(if (and (constantp slot-name-form)
(let ((slot-name (eval slot-name-form)))
(and (symbolp slot-name) (symbol-package slot-name))))
`(accessor-set-slot-value ,object-form ,slot-name-form ,new-value-form)
`(set-slot-value-normal ,object-form ,slot-name-form ,new-value-form)))
(defconstant *optimize-slot-boundp* nil)
(defun slot-boundp (object slot-name)
(let* ((class (class-of object))
(slot-definition (find-slot-definition class slot-name)))
(if (null slot-definition)
(slot-missing class object slot-name 'slot-boundp)
(slot-boundp-using-class class object slot-definition))))
(setf (gdefinition 'slot-boundp-normal) #'slot-boundp)
(define-compiler-macro slot-boundp (object-form slot-name-form)
(if (and (constantp slot-name-form)
(let ((slot-name (eval slot-name-form)))
(and (symbolp slot-name) (symbol-package slot-name))))
`(accessor-slot-boundp ,object-form ,slot-name-form)
`(slot-boundp-normal ,object-form ,slot-name-form)))
(defun slot-makunbound (object slot-name)
(let* ((class (class-of object))
(slot-definition (find-slot-definition class slot-name)))
(if (null slot-definition)
(slot-missing class object slot-name 'slot-makunbound)
(slot-makunbound-using-class class object slot-definition))))
(defun slot-exists-p (object slot-name)
(let ((class (class-of object)))
(not (null (find-slot-definition class slot-name)))))
;;;
;;; This isn't documented, but is used within PCL in a number of print
;;; object methods (see named-object-print-function).
;;;
(defun slot-value-or-default (object slot-name &optional (default "unbound"))
(if (slot-boundp object slot-name)
(slot-value object slot-name)
default))
;;;
;;;
;;;
(defun standard-instance-access (instance location)
(%instance-ref (std-instance-slots instance) location))
(defun funcallable-standard-instance-access (instance location)
(%instance-ref (fsc-instance-slots instance) location))
(defmethod slot-value-using-class ((class std-class)
(object standard-object)
(slotd standard-effective-slot-definition))
(let* ((location (slot-definition-location slotd))
(value (typecase location
(fixnum
(cond ((std-instance-p object)
(unless (eq 't (wrapper-state (std-instance-wrapper object)))
(check-wrapper-validity object))
(%instance-ref (std-instance-slots object) location))
((fsc-instance-p object)
(unless (eq 't (wrapper-state (fsc-instance-wrapper object)))
(check-wrapper-validity object))
(%instance-ref (fsc-instance-slots object) location))
(t (error "What kind of instance is this?"))))
(cons
(cdr location))
(t
(error "The slot ~s has neither :instance nor :class allocation, ~@
so it can't be read by the default ~s method."
slotd 'slot-value-using-class)))))
(if (eq value *slot-unbound*)
(slot-unbound class object (slot-definition-name slotd))
value)))
(defmethod (setf slot-value-using-class)
(new-value (class std-class)
(object standard-object)
(slotd standard-effective-slot-definition))
(let ((location (slot-definition-location slotd)))
(typecase location
(fixnum
(cond ((std-instance-p object)
(unless (eq 't (wrapper-state (std-instance-wrapper object)))
(check-wrapper-validity object))
(setf (%instance-ref (std-instance-slots object) location) new-value))
((fsc-instance-p object)
(unless (eq 't (wrapper-state (fsc-instance-wrapper object)))
(check-wrapper-validity object))
(setf (%instance-ref (fsc-instance-slots object) location) new-value))
(t (error "What kind of instance is this?"))))
(cons
(setf (cdr location) new-value))
(t
(error "The slot ~s has neither :instance nor :class allocation, ~@
so it can't be written by the default ~s method."
slotd '(setf slot-value-using-class))))))
(defmethod slot-boundp-using-class
((class std-class)
(object standard-object)
(slotd standard-effective-slot-definition))
(let* ((location (slot-definition-location slotd))
(value (typecase location
(fixnum
(cond ((std-instance-p object)
(unless (eq 't (wrapper-state (std-instance-wrapper object)))
(check-wrapper-validity object))
(%instance-ref (std-instance-slots object) location))
((fsc-instance-p object)
(unless (eq 't (wrapper-state (fsc-instance-wrapper object)))
(check-wrapper-validity object))
(%instance-ref (fsc-instance-slots object) location))
(t (error "What kind of instance is this?"))))
(cons
(cdr location))
(t
(error "The slot ~s has neither :instance nor :class allocation, ~@
so it can't be read by the default ~s method."
slotd 'slot-boundp-using-class)))))
(not (eq value *slot-unbound*))))
(defmethod slot-makunbound-using-class
((class std-class)
(object standard-object)
(slotd standard-effective-slot-definition))
(let ((location (slot-definition-location slotd)))
(typecase location
(fixnum
(cond ((std-instance-p object)
(unless (eq 't (wrapper-state (std-instance-wrapper object)))
(check-wrapper-validity object))
(setf (%instance-ref (std-instance-slots object) location) *slot-unbound*))
((fsc-instance-p object)
(unless (eq 't (wrapper-state (fsc-instance-wrapper object)))
(check-wrapper-validity object))
(setf (%instance-ref (fsc-instance-slots object) location) *slot-unbound*))
(t (error "What kind of instance is this?"))))
(cons
(setf (cdr location) *slot-unbound*))
(t
(error "The slot ~s has neither :instance nor :class allocation, ~@
so it can't be written by the default ~s method."
slotd 'slot-makunbound-using-class))))
nil)
(defmethod slot-value-using-class
((class structure-class)
(object structure-object)
(slotd structure-effective-slot-definition))
(let* ((function (slot-definition-internal-reader-function slotd))
(value (funcall function object)))
#+cmu (declare (type function function))
(if (eq value *slot-unbound*)
(slot-unbound class object (slot-definition-name slotd))
value)))
(defmethod (setf slot-value-using-class)
(new-value (class structure-class)
(object structure-object)
(slotd structure-effective-slot-definition))
(let ((function (slot-definition-internal-writer-function slotd)))
#+cmu (declare (type function function))
(funcall function new-value object)))
(defmethod slot-boundp-using-class
((class structure-class)
(object structure-object)
(slotd structure-effective-slot-definition))
#-new-kcl-wrapper t
#+new-kcl-wrapper
(let* ((function (slot-definition-internal-reader-function slotd))
(value (funcall function object)))
#+cmu (declare (type function function))
(not (eq value *slot-unbound*))))
(defmethod slot-makunbound-using-class
((class structure-class)
(object structure-object)
(slotd structure-effective-slot-definition))
(error "Structure slots can't be unbound"))
(defmethod slot-missing
((class t) instance slot-name operation &optional new-value)
(error "When attempting to ~A,~%the slot ~S is missing from the object ~S."
(ecase operation
(slot-value "read the slot's value (slot-value)")
(setf (format nil
"set the slot's value to ~S (setf of slot-value)"
new-value))
(slot-boundp "test to see if slot is bound (slot-boundp)")
(slot-makunbound "make the slot unbound (slot-makunbound)"))
slot-name
instance))
(defmethod slot-unbound ((class t) instance slot-name)
(error "The slot ~S is unbound in the object ~S." slot-name instance))
(defun slot-unbound-internal (instance position)
(slot-unbound (class-of instance) instance
(etypecase position
(fixnum
(nth position
(wrapper-instance-slots-layout (wrapper-of instance))))
(cons
(car position)))))
(defmethod allocate-instance ((class standard-class) &rest initargs)
(declare (ignore initargs))
(unless (class-finalized-p class) (finalize-inheritance class))
(allocate-standard-instance (class-wrapper class)))
(defmethod allocate-instance ((class structure-class) &rest initargs)
(declare (ignore initargs))
#-new-kcl-wrapper
(let ((constructor (class-defstruct-constructor class)))
(if constructor
(funcall constructor)
(error "Can't allocate an instance of class ~S" (class-name class))))
#+new-kcl-wrapper
(allocate-standard-instance (class-wrapper class)))
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