;;;; ANSI CL condition for unbound slots
(define-condition unbound-slot (cell-error)
- ((instance :reader unbound-slot-instance :initarg :instance)
- (slot :reader unbound-slot-slot :initarg :slot))
- (:report (lambda(condition stream)
- (format stream "The slot ~S is unbound in the object ~S."
- (unbound-slot-slot condition)
- (unbound-slot-instance condition)))))
+ ((instance :reader unbound-slot-instance :initarg :instance))
+ (:report (lambda (condition stream)
+ (format stream "The slot ~S is unbound in the object ~S."
+ (cell-error-name condition)
+ (unbound-slot-instance condition)))))
(defmethod wrapper-fetcher ((class standard-class))
'std-instance-wrapper)
(defmethod raw-instance-allocator ((class standard-class))
'allocate-standard-instance)
-;;; These four functions work on std-instances and fsc-instances. These are
+;;; These three 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)
- (setf (std-instance-wrapper inst) new))
- ((fsc-instance-p inst)
- (setf (fsc-instance-wrapper inst) new))
- (t
- (error "unrecognized instance type"))))
-
-(defun swap-wrappers-and-slots (i1 i2)
- (sb-sys:without-interrupts
- (cond ((std-instance-p i1)
- (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 "unrecognized instance type")))))
+(defun %swap-wrappers-and-slots (i1 i2)
+ (cond ((std-instance-p i1)
+ (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 "unrecognized instance type"))))
\f
-(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)))
-\f
-(defun find-slot-definition (class slot-name)
- (dolist (slot (class-slots class) nil)
- (when (eql slot-name (slot-definition-name slot))
- (return slot))))
+;;;; STANDARD-INSTANCE-ACCESS
-(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))))
+(declaim (inline standard-instance-access (setf standard-instance-access)
+ funcallable-standard-instance-access
+ (setf funcallable-standard-instance-access)))
-(setf (gdefinition 'slot-value-normal) #'slot-value)
+(defun standard-instance-access (instance location)
+ (clos-slots-ref (std-instance-slots instance) location))
-(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 (setf standard-instance-access) (new-value instance location)
+ (setf (clos-slots-ref (std-instance-slots instance) location) new-value))
-(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 new-value)
- (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 funcallable-standard-instance-access (instance location)
+ (clos-slots-ref (fsc-instance-slots instance) location))
-(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))))
+(defun (setf funcallable-standard-instance-access) (new-value instance location)
+ (setf (clos-slots-ref (fsc-instance-slots instance) location) new-value))
+\f
+;;;; SLOT-VALUE, (SETF SLOT-VALUE), SLOT-BOUNDP, SLOT-MAKUNBOUND
+
+(declaim (ftype (sfunction (t symbol) t) slot-value))
+(defun slot-value (object slot-name)
+ (let* ((wrapper (valid-wrapper-of object))
+ (cell (find-slot-cell wrapper slot-name))
+ (location (car cell))
+ (value
+ (cond ((fixnump location)
+ (if (std-instance-p object)
+ (standard-instance-access object location)
+ (funcallable-standard-instance-access object location)))
+ ((consp location)
+ (cdr location))
+ ((not cell)
+ (return-from slot-value
+ (values (slot-missing (wrapper-class* wrapper) object slot-name
+ 'slot-value))))
+ ((not location)
+ (return-from slot-value
+ (slot-value-using-class (wrapper-class* wrapper) object (cddr cell))))
+ (t
+ (bug "Bogus slot cell in SLOT-VALUE: ~S" cell)))))
+ (if (eq +slot-unbound+ value)
+ (slot-unbound (wrapper-class* wrapper) object slot-name)
+ value)))
+
+(define-compiler-macro slot-value (&whole form object slot-name
+ &environment env)
+ (if (and (constantp slot-name env)
+ (interned-symbol-p (constant-form-value slot-name env)))
+ `(accessor-slot-value ,object ,slot-name)
+ form))
-(setf (gdefinition 'slot-boundp-normal) #'slot-boundp)
+(defun set-slot-value (object slot-name new-value)
+ (let* ((wrapper (valid-wrapper-of object))
+ (cell (find-slot-cell wrapper slot-name))
+ (location (car cell))
+ (type-check-function (cadr cell)))
+ (when type-check-function
+ (funcall (the function type-check-function) new-value))
+ (cond ((fixnump location)
+ (if (std-instance-p object)
+ (setf (standard-instance-access object location) new-value)
+ (setf (funcallable-standard-instance-access object location)
+ new-value)))
+ ((consp location)
+ (setf (cdr location) new-value))
+ ((not cell)
+ (slot-missing (wrapper-class* wrapper) object slot-name 'setf new-value))
+ ((not location)
+ (setf (slot-value-using-class (wrapper-class* wrapper) object (cddr cell))
+ new-value))
+ (t
+ (bug "Bogus slot-cell in SET-SLOT-VALUE: ~S" cell))))
+ new-value)
+
+;;; A version of SET-SLOT-VALUE for use in safe code, where we want to
+;;; check types when writing to slots:
+;;; * Doesn't have an optimizing compiler-macro
+;;; * Isn't special-cased in WALK-METHOD-LAMBDA
+(defun safe-set-slot-value (object slot-name new-value)
+ (set-slot-value object slot-name new-value))
+
+(define-compiler-macro set-slot-value (&whole form object slot-name new-value
+ &environment env)
+ (if (and (constantp slot-name env)
+ (interned-symbol-p (constant-form-value slot-name env))
+ ;; We can't use the ACCESSOR-SET-SLOT-VALUE path in safe
+ ;; code, since it'll use the global automatically generated
+ ;; accessor, which won't do typechecking. (SLOT-OBJECT
+ ;; won't have been compiled with SAFETY 3, so SAFE-P will
+ ;; be NIL in MAKE-STD-WRITER-METHOD-FUNCTION).
+ (not (safe-code-p env)))
+ `(accessor-set-slot-value ,object ,slot-name ,new-value)
+ form))
-(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-boundp (object slot-name)
+ (let* ((wrapper (valid-wrapper-of object))
+ (cell (find-slot-cell wrapper slot-name))
+ (location (car cell))
+ (value
+ (cond ((fixnump location)
+ (if (std-instance-p object)
+ (standard-instance-access object location)
+ (funcallable-standard-instance-access object location)))
+ ((consp location)
+ (cdr location))
+ ((not cell)
+ (return-from slot-boundp
+ (and (slot-missing (wrapper-class* wrapper) object slot-name
+ 'slot-boundp)
+ t)))
+ ((not location)
+ (return-from slot-boundp
+ (slot-boundp-using-class (wrapper-class* wrapper) object (cddr cell))))
+ (t
+ (bug "Bogus slot cell in SLOT-VALUE: ~S" cell)))))
+ (not (eq +slot-unbound+ value))))
+
+(define-compiler-macro slot-boundp (&whole form object slot-name
+ &environment env)
+ (if (and (constantp slot-name env)
+ (interned-symbol-p (constant-form-value slot-name env)))
+ `(accessor-slot-boundp ,object ,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))))
+ (let* ((wrapper (valid-wrapper-of object))
+ (cell (find-slot-cell wrapper slot-name))
+ (location (car cell)))
+ (cond ((fixnump location)
+ (if (std-instance-p object)
+ (setf (standard-instance-access object location) +slot-unbound+)
+ (setf (funcallable-standard-instance-access object location)
+ +slot-unbound+)))
+ ((consp location)
+ (setf (cdr location) +slot-unbound+))
+ ((not cell)
+ (slot-missing (wrapper-class* wrapper) object slot-name 'slot-makunbound))
+ ((not location)
+ (slot-makunbound-using-class (wrapper-class* wrapper) object (cddr cell)))
+ (t
+ (bug "Bogus slot-cell in SLOT-MAKUNBOUND: ~S" cell))))
+ object)
(defun slot-exists-p (object slot-name)
(let ((class (class-of object)))
(not (null (find-slot-definition class slot-name)))))
+(defvar *unbound-slot-value-marker* (make-unprintable-object "unbound slot"))
+
;;; 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"))
+(defun slot-value-or-default (object slot-name &optional
+ (default *unbound-slot-value-marker*))
(if (slot-boundp object slot-name)
(slot-value object slot-name)
default))
-\f
-(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 std-object)
- (slotd standard-effective-slot-definition))
+ (object standard-object)
+ (slotd standard-effective-slot-definition))
+ ;; FIXME: Do we need this? SLOT-VALUE checks for obsolete
+ ;; instances. Are users allowed to call this directly?
+ (check-obsolete-instance object)
(let* ((location (slot-definition-location slotd))
- (value (typecase location
- (fixnum
- (cond ((std-instance-p object)
- ;; FIXME: EQ T (WRAPPER-STATE ..) is better done
- ;; through INVALID-WRAPPER-P (here and below).
- (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 "unrecognized instance type"))))
- (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)))))
+ (value
+ (typecase location
+ (fixnum
+ (cond ((std-instance-p object)
+ (clos-slots-ref (std-instance-slots object)
+ location))
+ ((fsc-instance-p object)
+ (clos-slots-ref (fsc-instance-slots object)
+ location))
+ (t (bug "unrecognized instance type in ~S"
+ 'slot-value-using-class))))
+ (cons
+ (cdr location))
+ (t
+ (instance-structure-protocol-error slotd
+ 'slot-value-using-class)))))
(if (eq value +slot-unbound+)
- (slot-unbound class object (slot-definition-name slotd))
- value)))
+ (values (slot-unbound class object (slot-definition-name slotd)))
+ value)))
(defmethod (setf slot-value-using-class)
- (new-value (class std-class)
- (object std-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 "unrecognized instance type"))))
- (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))))))
+ (new-value (class std-class)
+ (object standard-object)
+ (slotd standard-effective-slot-definition))
+ ;; FIXME: Do we need this? SET-SLOT-VALUE checks for obsolete
+ ;; instances. Are users allowed to call this directly?
+ (check-obsolete-instance object)
+ (let ((location (slot-definition-location slotd))
+ (type-check-function
+ (when (safe-p class)
+ (slot-definition-type-check-function slotd))))
+ (flet ((check (new-value)
+ (when type-check-function
+ (funcall (the function type-check-function) new-value))
+ new-value))
+ (typecase location
+ (fixnum
+ (cond ((std-instance-p object)
+ (setf (clos-slots-ref (std-instance-slots object) location)
+ (check new-value)))
+ ((fsc-instance-p object)
+ (setf (clos-slots-ref (fsc-instance-slots object) location)
+ (check new-value)))
+ (t (bug "unrecognized instance type in ~S"
+ '(setf slot-value-using-class)))))
+ (cons
+ (setf (cdr location) (check new-value)))
+ (t
+ (instance-structure-protocol-error
+ slotd '(setf slot-value-using-class)))))))
(defmethod slot-boundp-using-class
- ((class std-class)
- (object std-object)
- (slotd standard-effective-slot-definition))
+ ((class std-class)
+ (object standard-object)
+ (slotd standard-effective-slot-definition))
+ ;; FIXME: Do we need this? SLOT-BOUNDP checks for obsolete
+ ;; instances. Are users allowed to call this directly?
+ (check-obsolete-instance object)
(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 "unrecognized instance type"))))
- (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)))))
+ (value
+ (typecase location
+ (fixnum
+ (cond ((std-instance-p object)
+ (clos-slots-ref (std-instance-slots object)
+ location))
+ ((fsc-instance-p object)
+ (clos-slots-ref (fsc-instance-slots object)
+ location))
+ (t (bug "unrecognized instance type in ~S"
+ 'slot-boundp-using-class))))
+ (cons
+ (cdr location))
+ (t
+ (instance-structure-protocol-error slotd
+ 'slot-boundp-using-class)))))
(not (eq value +slot-unbound+))))
(defmethod slot-makunbound-using-class
- ((class std-class)
- (object std-object)
- (slotd standard-effective-slot-definition))
+ ((class std-class)
+ (object standard-object)
+ (slotd standard-effective-slot-definition))
+ (check-obsolete-instance object)
(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 "unrecognized instance type"))))
+ (setf (clos-slots-ref (std-instance-slots object) location)
+ +slot-unbound+))
+ ((fsc-instance-p object)
+ (setf (clos-slots-ref (fsc-instance-slots object) location)
+ +slot-unbound+))
+ (t (bug "unrecognized instance type in ~S"
+ 'slot-makunbound-using-class))))
(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)
+ (instance-structure-protocol-error slotd
+ 'slot-makunbound-using-class))))
+ object)
+
+(defmethod slot-value-using-class
+ ((class condition-class)
+ (object condition)
+ (slotd condition-effective-slot-definition))
+ (let ((fun (slot-definition-reader-function slotd)))
+ (declare (type function fun))
+ (funcall fun object)))
+
+(defmethod (setf slot-value-using-class)
+ (new-value
+ (class condition-class)
+ (object condition)
+ (slotd condition-effective-slot-definition))
+ (let ((fun (slot-definition-writer-function slotd)))
+ (declare (type function fun))
+ (funcall fun new-value object)))
+
+(defmethod slot-boundp-using-class
+ ((class condition-class)
+ (object condition)
+ (slotd condition-effective-slot-definition))
+ (let ((fun (slot-definition-boundp-function slotd)))
+ (declare (type function fun))
+ (funcall fun object)))
+
+(defmethod slot-makunbound-using-class ((class condition-class) object slot)
+ (error "attempt to unbind slot ~S in condition object ~S."
+ slot object))
(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)))
+ (value (funcall function object)))
(declare (type function function))
+ ;; FIXME: Is this really necessary? Structure slots should surely
+ ;; never be unbound!
(if (eq value +slot-unbound+)
- (slot-unbound class object (slot-definition-name slotd))
- value)))
+ (values (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))
+ (object structure-object)
+ (slotd structure-effective-slot-definition))
(let ((function (slot-definition-internal-writer-function slotd)))
(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))
+ ((class structure-class)
+ (object structure-object)
+ (slotd structure-effective-slot-definition))
t)
(defmethod slot-makunbound-using-class
- ((class structure-class)
- (object structure-object)
- (slotd structure-effective-slot-definition))
+ ((class structure-class)
+ (object structure-object)
+ (slotd structure-effective-slot-definition))
(error "Structure slots can't be unbound."))
\f
(defmethod slot-missing
- ((class t) instance slot-name operation &optional new-value)
+ ((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 whether slot is bound (SLOT-BOUNDP)")
- (slot-makunbound "make the slot unbound (SLOT-MAKUNBOUND)"))
- slot-name
- instance))
+ (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 whether 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 'unbound-slot :slot slot-name :instance instance))
+ (restart-case
+ (error 'unbound-slot :name slot-name :instance instance)
+ (use-value (v)
+ :report "Return a value as the slot-value."
+ :interactive read-evaluated-form
+ v)
+ (store-value (v)
+ :report "Store and return a value as the slot-value."
+ :interactive read-evaluated-form
+ (setf (slot-value instance slot-name) v))))
(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)))))
+ (values
+ (slot-unbound
+ (class-of instance)
+ instance
+ (etypecase position
+ (fixnum
+ (nth position (wrapper-instance-slots-layout (wrapper-of instance))))
+ (cons
+ (car position))))))
\f
+;;; FIXME: AMOP says that allocate-instance imples finalize-inheritance
+;;; if the class is not yet finalized, but we don't seem to be taking
+;;; care of this for non-standard-classes.x
(defmethod allocate-instance ((class standard-class) &rest initargs)
(declare (ignore initargs))
- (unless (class-finalized-p class) (finalize-inheritance class))
+ (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))
(let ((constructor (class-defstruct-constructor class)))
(if constructor
- (funcall constructor)
- (error "can't allocate an instance of class ~S" (class-name class)))))
+ (funcall constructor)
+ (allocate-standard-instance (class-wrapper class)))))
+
+;;; FIXME: It would be nicer to have allocate-instance return
+;;; uninitialized objects for conditions as well.
+(defmethod allocate-instance ((class condition-class) &rest initargs)
+ (declare (ignore initargs))
+ (make-condition (class-name class)))
+
+(defmethod allocate-instance ((class built-in-class) &rest initargs)
+ (declare (ignore initargs))
+ (error "Cannot allocate an instance of ~S." class)) ; So sayeth AMOP
+
+;;; AMOP says that CLASS-SLOTS signals an error for unfinalized classes.
+(defmethod class-slots :before ((class slot-class))
+ (unless (class-finalized-p class)
+ (error 'simple-reference-error
+ :format-control "~S called on ~S, which is not yet finalized."
+ :format-arguments (list 'class-slots class)
+ :references (list '(:amop :generic-function class-slots)))))