0.8.20.19:

[sbcl.git] / src / pcl / std-class.lisp

diff --git a/src/pcl/std-class.lisp b/src/pcl/std-class.lisp
index 3a6b3b9..09f820a 100644 (file)
--- a/src/pcl/std-class.lisp
+++ b/src/pcl/std-class.lisp
@@ -943,13 +943,21 @@
          :class class
          initargs))
 
+;;; I (CSR) am not sure, but I believe that the particular order of
+;;; slots is quite important: it is ideal to attempt to have a
+;;; constant slot location for the same notional slots as much as
+;;; possible, so that clever discriminating functions (ONE-INDEX et
+;;; al.) have a chance of working.  The below at least walks through
+;;; the slots predictably, but maybe it would be good to compute some
+;;; kind of optimal slot layout by looking at locations of slots in
+;;; superclasses?
 (defmethod compute-slots ((class std-class))
   ;; As specified, we must call COMPUTE-EFFECTIVE-SLOT-DEFINITION once
   ;; for each different slot name we find in our superclasses. Each
   ;; call receives the class and a list of the dslotds with that name.
   ;; The list is in most-specific-first order.
   (let ((name-dslotds-alist ()))
-    (dolist (c (class-precedence-list class))
+    (dolist (c (reverse (class-precedence-list class)))
       (dolist (slot (class-direct-slots c))
        (let* ((name (slot-definition-name slot))
               (entry (assq name name-dslotds-alist)))
@@ -959,8 +967,8 @@
     (mapcar (lambda (direct)
              (compute-effective-slot-definition class
                                                 (car direct)
-                                                (nreverse (cdr direct))))
-           name-dslotds-alist)))
+                                                (cdr direct)))
+           (nreverse name-dslotds-alist))))
 
 (defmethod compute-slots ((class standard-class))
   (call-next-method))
@@ -1489,8 +1497,12 @@
 (defmethod class-default-initargs      ((class built-in-class)) ())
 
 (defmethod validate-superclass ((c class) (s built-in-class))
-  (or (eq s *the-class-t*)
-      (eq s *the-class-stream*)))
+  (or (eq s *the-class-t*) (eq s *the-class-stream*)
+      ;; FIXME: bad things happen if someone tries to mix in both
+      ;; FILE-STREAM and STRING-STREAM (as they have the same
+      ;; layout-depthoid).  Is there any way we can provide a useful
+      ;; error message?  -- CSR, 2005-05-03
+      (eq s *the-class-file-stream*) (eq s *the-class-string-stream*)))
 \f
 ;;; Some necessary methods for FORWARD-REFERENCED-CLASS
 (defmethod class-direct-slots ((class forward-referenced-class)) ())