-(defun make-std-writer-method-function (class-name slot-name)
- (let* ((pv-table-symbol (gensym))
- (initargs (copy-tree
- (make-method-function
- (lambda (nv instance)
- (pv-binding1 (.pv. .calls.
- (symbol-value pv-table-symbol)
- (instance) (instance-slots))
- (instance-write-internal
- .pv. instance-slots 1 nv
- (setf (slot-value instance slot-name) nv))))))))
- (setf (getf (getf initargs :plist) :slot-name-lists)
- (list nil (list nil slot-name)))
- (setf (getf (getf initargs :plist) :pv-table-symbol) pv-table-symbol)
- (list* :method-spec `(writer-method ,class-name ,slot-name)
- initargs)))
+(defun make-std-writer-method-function (class-or-name slot-name)
+ (let* ((class (when (eq *boot-state* 'complete)
+ (if (typep class-or-name 'class)
+ class-or-name
+ (find-class class-or-name nil))))
+ (safe-p (and class
+ (safe-p class)))
+ (check-fun (lambda (new-value instance)
+ (let* ((class (class-of instance))
+ (slotd (find-slot-definition class slot-name))
+ (type-check-function
+ (when slotd
+ (slot-definition-type-check-function slotd))))
+ (when type-check-function
+ (funcall type-check-function new-value)))))
+ (initargs (copy-tree
+ (if safe-p
+ (make-method-function
+ (lambda (nv instance)
+ (funcall check-fun nv instance)
+ (pv-binding1 ((bug "Please report this")
+ (instance) (instance-slots))
+ (instance-write-internal
+ .pv. instance-slots 0 nv
+ (setf (slot-value instance slot-name) nv)))))
+ (make-method-function
+ (lambda (nv instance)
+ (pv-binding1 ((bug "Please report this")
+ (instance) (instance-slots))
+ (instance-write-internal
+ .pv. instance-slots 0 nv
+ (setf (slot-value instance slot-name) nv)))))))))
+ (setf (getf (getf initargs 'plist) :slot-name-lists)
+ (list nil (list nil slot-name)))
+ initargs))
+
+(defun make-std-boundp-method-function (class-or-name slot-name)
+ (declare (ignore class-or-name))
+ (let* ((initargs (copy-tree
+ (make-method-function
+ (lambda (instance)
+ (pv-binding1 ((bug "Please report this")
+ (instance) (instance-slots))
+ (instance-boundp-internal
+ .pv. instance-slots 0
+ (slot-boundp instance slot-name))))))))
+ (setf (getf (getf initargs 'plist) :slot-name-lists)
+ (list (list nil slot-name)))
+ initargs))
+\f
+;;;; FINDING SLOT DEFINITIONS
+;;;
+;;; Historical PCL found slot definitions by iterating over
+;;; CLASS-SLOTS, which is O(N) for number of slots, and moreover
+;;; requires a GF call (for SLOT-DEFINITION-NAME) for each slot in
+;;; list up to the desired one.
+;;;
+;;; Current SBCL hashes the effective slot definitions, and some
+;;; information pulled out from them into a simple-vector, with bucket
+;;; chains made out of plists keyed by the slot names. This fixes
+;;; gives O(1) performance, and avoid the GF calls.
+;;;
+;;; MAKE-SLOT-TABLE constructs the hashed vector out of a list of
+;;; effective slot definitions and the class they pertain to, and
+;;; FIND-SLOT-DEFINITION knows how to look up slots in that vector.
+;;;
+;;; The only bit of cleverness in the implementation is to make the
+;;; vectors fairly tight, but always longer then 0 elements:
+;;;
+;;; -- We don't want to waste huge amounts of space no these vectors,
+;;; which are mostly required by things like SLOT-VALUE with a
+;;; variable slot name, so a constant extension over the minimum
+;;; size seems like a good choise.
+;;;
+;;; -- As long as the vector always has a length > 0
+;;; FIND-SLOT-DEFINITION doesn't need to handle the rare case of an
+;;; empty vector separately: it just returns a NIL.
+;;;
+;;; In addition to the slot-definition we also store the slot-location
+;;; and type-check function for instances of standard metaclasses, so
+;;; that SLOT-VALUE &co using variable slot names can get at them
+;;; without additional GF calls.
+;;;
+;;; Notes:
+;;; It would be probably better to store the vector in wrapper
+;;; instead: one less memory indirection, one less CLOS slot
+;;; access to get at it.
+;;;
+;;; It would also be nice to have STANDARD-INSTANCE-STRUCTURE-P
+;;; generic instead of checking versus STANDARD-CLASS and
+;;; FUNCALLABLE-STANDARD-CLASS.
projects / sbcl.git / blobdiff