(ewoc--current-dll): New var.

(ewoc--node-next, ewoc--node-prev, ewoc--node-nth): Don't
take DLL arg.  Instead, use `ewoc--current-dll'.  Update all callers.
(ewoc--set-buffer-bind-dll-let*): Bind `ewoc--current-dll', not `dll'.
(ewoc--adjust): Use `ewoc--current-dll'.
(ewoc-next, ewoc-prev, ewoc-nth): Bind `ewoc--current-dll'.

2 files changed, 70 insertions, 55 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index ce5cf60fcbb..ec6e6aab37e 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,12 @@
+2006-05-26  Thien-Thi Nguyen  <ttn@gnu.org>
+
+        * emacs-lisp/ewoc.el (ewoc--current-dll): New var.
+        (ewoc--node-next, ewoc--node-prev, ewoc--node-nth): Don't take
+        DLL arg.  Instead, use ewoc--current-dll.  Update all callers.
+        (ewoc--set-buffer-bind-dll-let*): Bind ewoc--current-dll, not `dll'.
+        (ewoc--adjust): Use ewoc--current-dll.
+        (ewoc-next, ewoc-prev, ewoc-nth): Bind ewoc--current-dll.
+
 2006-05-26  Carsten Dominik  <dominik@science.uva.nl>
 
         * textmodes/org.el: (org-next-item, org-previous-item): Emit more
diff --git a/lisp/emacs-lisp/ewoc.el b/lisp/emacs-lisp/ewoc.el
index 2cb90738072..6f14fb37cf5 100644
--- a/lisp/emacs-lisp/ewoc.el
+++ b/lisp/emacs-lisp/ewoc.el
@@ -134,7 +134,9 @@
 
 ;; The doubly linked list is implemented as a circular list
 ;; with a dummy node first and last. The dummy node is used as
-;; "the dll" (or rather is the dll handle passed around).
+;; "the dll" (or rather the dynamically bound `ewoc--current-dll').
+
+(defvar ewoc--current-dll)
 
 (defstruct (ewoc--node
             (:type vector)              ;required for ewoc--node-branch hack
@@ -146,29 +148,31 @@
 
 \(fn NODE CHILD)")
 
-(defun ewoc--node-next (dll node)
+(defun ewoc--node-next (node)
   "Return the node after NODE, or nil if NODE is the last node."
-  (unless (eq (ewoc--node-right node) dll) (ewoc--node-right node)))
+  (let ((R (ewoc--node-right node)))
+    (unless (eq ewoc--current-dll R) R)))
 
-(defun ewoc--node-prev (dll node)
+(defun ewoc--node-prev (node)
   "Return the node before NODE, or nil if NODE is the first node."
-  (unless (eq (ewoc--node-left node) dll) (ewoc--node-left node)))
-
-(defun ewoc--node-nth (dll n)
-  "Return the Nth node from the doubly linked list DLL.
-N counts from zero. If DLL is not that long, nil is returned.
-If N is negative, return the -(N+1)th last element.
-Thus, (ewoc--node-nth dll 0) returns the first node,
-and (ewoc--node-nth dll -1) returns the last node."
+  (let ((L (ewoc--node-left node)))
+    (unless (eq ewoc--current-dll L) L)))
+
+(defun ewoc--node-nth (n)
+  "Return the Nth node from the doubly linked list `ewoc--current-dll'.
+N counts from zero.  If N is negative, return the -(N+1)th last element.
+If N is out of range, return nil.
+Thus, (ewoc--node-nth 0) returns the first node,
+and (ewoc--node-nth -1) returns the last node."
   ;; Branch 0 ("follow left pointer") is used when n is negative.
   ;; Branch 1 ("follow right pointer") is used otherwise.
   (let* ((branch (if (< n 0) 0 1))
-         (node   (ewoc--node-branch dll branch)))
+         (node   (ewoc--node-branch ewoc--current-dll branch)))
     (if (< n 0) (setq n (- -1 n)))
-    (while (and (not (eq dll node)) (> n 0))
+    (while (and (not (eq ewoc--current-dll node)) (> n 0))
       (setq node (ewoc--node-branch node branch))
       (setq n (1- n)))
-    (unless (eq dll node) node)))
+    (unless (eq ewoc--current-dll node) node)))
 
 (defun ewoc-location (node)
   "Return the start location of NODE."
@@ -186,13 +190,13 @@ and (ewoc--node-nth dll -1) returns the last node."
 
 (defmacro ewoc--set-buffer-bind-dll-let* (ewoc varlist &rest forms)
   "Execute FORMS with ewoc--buffer selected as current buffer,
-dll bound to ewoc--dll, and VARLIST bound as in a let*.
-dll will be bound when VARLIST is initialized, but the current
-buffer will *not* have been changed.
+`ewoc--current-dll' bound to the dll, and VARLIST bound as in a let*.
+`ewoc--current-dll' will be bound when VARLIST is initialized, but
+the current buffer will *not* have been changed.
 Return value of last form in FORMS."
   (let ((hnd (make-symbol "ewoc")))
     `(let* ((,hnd ,ewoc)
-            (dll (ewoc--dll ,hnd))
+            (ewoc--current-dll (ewoc--dll ,hnd))
             ,@varlist)
        (with-current-buffer (ewoc--buffer ,hnd)
          ,@forms))))
@@ -213,14 +217,14 @@ BUT if it is the header or the footer in EWOC return nil instead."
   ;; BEG, to END.  BEG and END are buffer positions describing NODE's left
   ;; neighbor.  This operation is functionally equivalent to temporarily
   ;; setting these nodes' markers' insertion type to t around the pretty-print
-  ;; call that precedes the call to `ewoc-adjust', and then changing them back
+  ;; call that precedes the call to `ewoc--adjust', and then changing them back
   ;; to nil.
   (when (< beg end)
     (let (m)
       (while (and (= beg (setq m (ewoc--node-start-marker node)))
                   (progn
                     (set-marker m end)
-                    (not (eq dll node))))
+                    (not (eq ewoc--current-dll node))))
         (setq node (ewoc--node-right node))))))
 
 (defun ewoc--insert-new-node (node data pretty-printer)
@@ -306,20 +310,20 @@ respectively, of the ewoc."
   "Enter DATA first in EWOC.
 Return the new node."
   (ewoc--set-buffer-bind-dll ewoc
-    (ewoc-enter-after ewoc (ewoc--node-nth dll 0) data)))
+    (ewoc-enter-after ewoc (ewoc--node-nth 0) data)))
 
 (defun ewoc-enter-last (ewoc data)
   "Enter DATA last in EWOC.
 Return the new node."
   (ewoc--set-buffer-bind-dll ewoc
-    (ewoc-enter-before ewoc (ewoc--node-nth dll -1) data)))
+    (ewoc-enter-before ewoc (ewoc--node-nth -1) data)))
 
 
 (defun ewoc-enter-after (ewoc node data)
   "Enter a new element DATA after NODE in EWOC.
 Return the new node."
   (ewoc--set-buffer-bind-dll ewoc
-    (ewoc-enter-before ewoc (ewoc--node-next dll node) data)))
+    (ewoc-enter-before ewoc (ewoc--node-next node) data)))
 
 (defun ewoc-enter-before (ewoc node data)
   "Enter a new element DATA before NODE in EWOC.
@@ -332,28 +336,30 @@ Return the new node."
 Return nil if NODE is nil or the last element."
   (when node
     (ewoc--filter-hf-nodes
-     ewoc (ewoc--node-next (ewoc--dll ewoc) node))))
+     ewoc (let ((ewoc--current-dll (ewoc--dll ewoc)))
+            (ewoc--node-next node)))))
 
 (defun ewoc-prev (ewoc node)
   "Return the node in EWOC that precedes NODE.
 Return nil if NODE is nil or the first element."
   (when node
     (ewoc--filter-hf-nodes
-     ewoc
-     (ewoc--node-prev (ewoc--dll ewoc) node))))
+     ewoc (let ((ewoc--current-dll (ewoc--dll ewoc)))
+            (ewoc--node-prev node)))))
 
 
 (defun ewoc-nth (ewoc n)
   "Return the Nth node.
 N counts from zero.  Return nil if there is less than N elements.
 If N is negative, return the -(N+1)th last element.
-Thus, (ewoc-nth dll 0) returns the first node,
-and (ewoc-nth dll -1) returns the last node.
+Thus, (ewoc-nth ewoc 0) returns the first node,
+and (ewoc-nth ewoc -1) returns the last node.
 Use `ewoc-data' to extract the data from the node."
   ;; Skip the header (or footer, if n is negative).
   (setq n (if (< n 0) (1- n) (1+ n)))
   (ewoc--filter-hf-nodes ewoc
-                  (ewoc--node-nth (ewoc--dll ewoc) n)))
+                         (let ((ewoc--current-dll (ewoc--dll ewoc)))
+                           (ewoc--node-nth n))))
 
 (defun ewoc-map (map-function ewoc &rest args)
   "Apply MAP-FUNCTION to all elements in EWOC.
@@ -370,12 +376,12 @@ arguments will be passed to MAP-FUNCTION."
   (ewoc--set-buffer-bind-dll-let* ewoc
       ((footer (ewoc--footer ewoc))
        (pp (ewoc--pretty-printer ewoc))
-       (node (ewoc--node-nth dll 1)))
+       (node (ewoc--node-nth 1)))
     (save-excursion
       (while (not (eq node footer))
         (if (apply map-function (ewoc--node-data node) args)
             (ewoc--refresh-node pp node))
-        (setq node (ewoc--node-next dll node))))))
+        (setq node (ewoc--node-next node))))))
 
 (defun ewoc-delete (ewoc &rest nodes)
   "Delete NODES from EWOC."
@@ -387,7 +393,7 @@ arguments will be passed to MAP-FUNCTION."
       (if (eq (ewoc--last-node ewoc) node)
           (setf (ewoc--last-node ewoc) nil))
       (delete-region (ewoc--node-start-marker node)
-                     (ewoc--node-start-marker (ewoc--node-next dll node)))
+                     (ewoc--node-start-marker (ewoc--node-next node)))
       (set-marker (ewoc--node-start-marker node) nil)
       (setf L (ewoc--node-left  node)
             R (ewoc--node-right node)
@@ -406,14 +412,14 @@ if it changes it.
 The PREDICATE is called with the element as its first argument.  If any
 ARGS are given they will be passed to the PREDICATE."
   (ewoc--set-buffer-bind-dll-let* ewoc
-      ((node (ewoc--node-nth dll 1))
+      ((node (ewoc--node-nth 1))
        (footer (ewoc--footer ewoc))
        (goodbye nil)
        (inhibit-read-only t))
     (while (not (eq node footer))
       (unless (apply predicate (ewoc--node-data node) args)
         (push node goodbye))
-      (setq node (ewoc--node-next dll node)))
+      (setq node (ewoc--node-next node)))
     (apply 'ewoc-delete ewoc goodbye)))
 
 (defun ewoc-locate (ewoc &optional pos guess)
@@ -430,22 +436,22 @@ If the EWOC is empty, nil is returned."
 
     (cond
      ;; Nothing present?
-     ((eq (ewoc--node-nth dll 1) (ewoc--node-nth dll -1))
+     ((eq (ewoc--node-nth 1) (ewoc--node-nth -1))
       nil)
 
      ;; Before second elem?
-     ((< pos (ewoc--node-start-marker (ewoc--node-nth dll 2)))
-      (ewoc--node-nth dll 1))
+     ((< pos (ewoc--node-start-marker (ewoc--node-nth 2)))
+      (ewoc--node-nth 1))
 
      ;; After one-before-last elem?
-     ((>= pos (ewoc--node-start-marker (ewoc--node-nth dll -2)))
-      (ewoc--node-nth dll -2))
+     ((>= pos (ewoc--node-start-marker (ewoc--node-nth -2)))
+      (ewoc--node-nth -2))
 
      ;; We now know that pos is within a elem.
      (t
       ;; Make an educated guess about which of the three known
       ;; node'es (the first, the last, or GUESS) is nearest.
-      (let* ((best-guess (ewoc--node-nth dll 1))
+      (let* ((best-guess (ewoc--node-nth 1))
              (distance (abs (- pos (ewoc--node-start-marker best-guess)))))
         (when guess
           (let ((d (abs (- pos (ewoc--node-start-marker guess)))))
@@ -453,13 +459,13 @@ If the EWOC is empty, nil is returned."
               (setq distance d)
               (setq best-guess guess))))
 
-        (let* ((g (ewoc--node-nth dll -1))      ;Check the last elem
+        (let* ((g (ewoc--node-nth -1))  ;Check the last elem
                (d (abs (- pos (ewoc--node-start-marker g)))))
           (when (< d distance)
             (setq distance d)
             (setq best-guess g)))
 
-        (when (ewoc--last-node ewoc) ;Check "previous".
+        (when (ewoc--last-node ewoc)    ;Check "previous".
           (let* ((g (ewoc--last-node ewoc))
                  (d (abs (- pos (ewoc--node-start-marker g)))))
             (when (< d distance)
@@ -476,14 +482,14 @@ If the EWOC is empty, nil is returned."
               (ewoc--node-start-marker best-guess))
           ;; Loop until we are exactly one node too far down...
           (while (>= pos (ewoc--node-start-marker best-guess))
-            (setq best-guess (ewoc--node-next dll best-guess)))
+            (setq best-guess (ewoc--node-next best-guess)))
           ;; ...and return the previous node.
-          (ewoc--node-prev dll best-guess))
+          (ewoc--node-prev best-guess))
 
          ;; Pos is before best-guess
          (t
           (while (< pos (ewoc--node-start-marker best-guess))
-            (setq best-guess (ewoc--node-prev dll best-guess)))
+            (setq best-guess (ewoc--node-prev best-guess)))
           best-guess)))))))
 
 (defun ewoc-invalidate (ewoc &rest nodes)
@@ -507,10 +513,10 @@ Return the node we moved to."
         (setq arg (1- arg)))
       (while (and node (> arg 0))
         (setq arg (1- arg))
-        (setq node (ewoc--node-prev dll node)))
+        (setq node (ewoc--node-prev node)))
       ;; Never step above the first element.
       (unless (ewoc--filter-hf-nodes ewoc node)
-        (setq node (ewoc--node-nth dll 1)))
+        (setq node (ewoc--node-nth 1)))
       (ewoc-goto-node ewoc node))))
 
 (defun ewoc-goto-next (ewoc arg)
@@ -520,10 +526,10 @@ Return the node (or nil if we just passed the last node)."
       ((node (ewoc-locate ewoc (point))))
     (while (and node (> arg 0))
       (setq arg (1- arg))
-      (setq node (ewoc--node-next dll node)))
+      (setq node (ewoc--node-next node)))
     ;; Never step below the first element.
     ;; (unless (ewoc--filter-hf-nodes ewoc node)
-    ;;   (setq node (ewoc--node-nth dll -2)))
+    ;;   (setq node (ewoc--node-nth -2)))
     (ewoc-goto-node ewoc node)))
 
 (defun ewoc-goto-node (ewoc node)
@@ -542,15 +548,15 @@ number of elements needs to be refreshed."
   (ewoc--set-buffer-bind-dll-let* ewoc
       ((footer (ewoc--footer ewoc)))
     (let ((inhibit-read-only t))
-      (delete-region (ewoc--node-start-marker (ewoc--node-nth dll 1))
+      (delete-region (ewoc--node-start-marker (ewoc--node-nth 1))
                      (ewoc--node-start-marker footer))
       (goto-char (ewoc--node-start-marker footer))
       (let ((pp (ewoc--pretty-printer ewoc))
-            (node (ewoc--node-nth dll 1)))
+            (node (ewoc--node-nth 1)))
         (while (not (eq node footer))
           (set-marker (ewoc--node-start-marker node) (point))
           (funcall pp (ewoc--node-data node))
-          (setq node (ewoc--node-next dll node)))))
+          (setq node (ewoc--node-next node)))))
     (set-marker (ewoc--node-start-marker footer) (point))))
 
 (defun ewoc-collect (ewoc predicate &rest args)
@@ -567,12 +573,12 @@ If more than two arguments are given the
 remaining arguments will be passed to PREDICATE."
   (ewoc--set-buffer-bind-dll-let* ewoc
       ((header (ewoc--header ewoc))
-       (node (ewoc--node-nth dll -2))
+       (node (ewoc--node-nth -2))
        result)
     (while (not (eq node header))
       (if (apply predicate (ewoc--node-data node) args)
           (push (ewoc--node-data node) result))
-      (setq node (ewoc--node-prev dll node)))
+      (setq node (ewoc--node-prev node)))
     (nreverse result)))
 
 (defun ewoc-buffer (ewoc)