Make the eww buffers read-only

[gnu-emacs] / lisp / emacs-lisp / avl-tree.el

diff --git a/lisp/emacs-lisp/avl-tree.el b/lisp/emacs-lisp/avl-tree.el
index e8b7a1f9a8b34713bc9216a9df6a911923b2ea4f..813576efb469adfdc3065df17234743bdaf580bb 100644 (file)
--- a/lisp/emacs-lisp/avl-tree.el
+++ b/lisp/emacs-lisp/avl-tree.el
@@ -1,12 +1,12 @@
 ;;; avl-tree.el --- balanced binary trees, AVL-trees
 
 ;;; avl-tree.el --- balanced binary trees, AVL-trees
 

-;; Copyright (C) 1995, 2007-2011  Free Software Foundation, Inc.
+;; Copyright (C) 1995, 2007-2014 Free Software Foundation, Inc.

 
 ;; Author: Per Cederqvist <ceder@lysator.liu.se>
 ;;         Inge Wallin <inge@lysator.liu.se>
 ;;         Thomas Bellman <bellman@lysator.liu.se>
 ;;         Toby Cubitt <toby-predictive@dr-qubit.org>
 
 ;; Author: Per Cederqvist <ceder@lysator.liu.se>
 ;;         Inge Wallin <inge@lysator.liu.se>
 ;;         Thomas Bellman <bellman@lysator.liu.se>
 ;;         Toby Cubitt <toby-predictive@dr-qubit.org>

-;; Maintainer: FSF
+;; Maintainer: emacs-devel@gnu.org

 ;; Created: 10 May 1991
 ;; Keywords: extensions, data structures, AVL, tree
 
 ;; Created: 10 May 1991
 ;; Keywords: extensions, data structures, AVL, tree
 


@@ -31,7 +31,7 @@
 ;; deleting, and retrieving data from an AVL tree containing n elements
 ;; is O(log n). It is somewhat more rigidly balanced than other
 ;; self-balancing binary trees (such as red-black trees and AA trees),
 ;; deleting, and retrieving data from an AVL tree containing n elements
 ;; is O(log n). It is somewhat more rigidly balanced than other
 ;; self-balancing binary trees (such as red-black trees and AA trees),

-;; making insertion slighty slower, deletion somewhat slower, and
+;; making insertion slightly slower, deletion somewhat slower, and

 ;; retrieval somewhat faster (the asymptotic scaling is of course the
 ;; same for all types). Thus it may be a good choice when the tree will
 ;; be relatively static, i.e. data will be retrieved more often than
 ;; retrieval somewhat faster (the asymptotic scaling is of course the
 ;; same for all types). Thus it may be a good choice when the tree will
 ;; be relatively static, i.e. data will be retrieved more often than


@@ -74,7 +74,7 @@
   cmpfun)
 
 (defmacro avl-tree--root (tree)
   cmpfun)
 
 (defmacro avl-tree--root (tree)

-  ;; Return the root node for an avl-tree.  INTERNAL USE ONLY.
+  ;; Return the root node for an AVL tree.  INTERNAL USE ONLY.

   `(avl-tree--node-left (avl-tree--dummyroot ,tree)))
 
 (defsetf avl-tree--root (tree) (node)
   `(avl-tree--node-left (avl-tree--dummyroot ,tree)))
 
 (defsetf avl-tree--root (tree) (node)


@@ -206,7 +206,7 @@ Return t if the height of the tree has shrunk."
 
 Return cons cell (SHRUNK . DATA), where SHRUNK is t if the
 height of the tree has shrunk and nil otherwise, and DATA is
 
 Return cons cell (SHRUNK . DATA), where SHRUNK is t if the
 height of the tree has shrunk and nil otherwise, and DATA is

-the releted data."
+the related data."

   (let ((br (avl-tree--node-branch root branch)))
     (cond
      ;; DATA not in tree.
   (let ((br (avl-tree--node-branch root branch)))
     (cond
      ;; DATA not in tree.


@@ -260,7 +260,7 @@ Return t if the height of the tree has grown."
        (opp (avl-tree--switch-dir dir))
        ;; direction 0,1 -> sign factor -1,+1
        (sgn (avl-tree--dir-to-sign dir))
        (opp (avl-tree--switch-dir dir))
        ;; direction 0,1 -> sign factor -1,+1
        (sgn (avl-tree--dir-to-sign dir))

-        p1 p2 b2 result)
+        p1 p2 b2)

     (cond
      ((< (* sgn (avl-tree--node-balance br)) 0)
       (setf (avl-tree--node-balance br) 0)
     (cond
      ((< (* sgn (avl-tree--node-balance br)) 0)
       (setf (avl-tree--node-balance br) 0)


@@ -295,9 +295,9 @@ Return t if the height of the tree has grown."
                (if (> (* sgn b2) 0) (- sgn) 0)
              (avl-tree--node-balance p1)
                (if (< (* sgn b2) 0) sgn 0)
                (if (> (* sgn b2) 0) (- sgn) 0)
              (avl-tree--node-balance p1)
                (if (< (* sgn b2) 0) sgn 0)

-             (avl-tree--node-branch node branch) p2
-             (avl-tree--node-balance
-              (avl-tree--node-branch node branch)) 0))
+                (avl-tree--node-branch node branch) p2))
+      (setf (avl-tree--node-balance
+             (avl-tree--node-branch node branch)) 0)

       nil))))
 
 (defun avl-tree--do-enter (cmpfun root branch data &optional updatefun)
       nil))))
 
 (defun avl-tree--do-enter (cmpfun root branch data &optional updatefun)


@@ -339,6 +339,16 @@ inserted data."
        (cons nil newdata))  ; return value
       ))))
 
        (cons nil newdata))  ; return value
       ))))
 

+(defun avl-tree--check (tree)
+  "Check the tree's balance."
+  (avl-tree--check-node (avl-tree--root tree)))
+(defun avl-tree--check-node (node)
+  (if (null node) 0
+    (let ((dl (avl-tree--check-node (avl-tree--node-left node)))
+         (dr (avl-tree--check-node (avl-tree--node-right node))))
+      (assert (= (- dr dl) (avl-tree--node-balance node)))
+      (1+ (max dl dr)))))
+

 ;; ----------------------------------------------------------------
 
 
 ;; ----------------------------------------------------------------
 
 


@@ -372,7 +382,7 @@ itself."
 
 ;;; INTERNAL USE ONLY
 (defun avl-tree--do-copy (root)
 
 ;;; INTERNAL USE ONLY
 (defun avl-tree--do-copy (root)

-  "Copy the avl tree with ROOT as root. Highly recursive."
+  "Copy the AVL tree with ROOT as root.  Highly recursive."

   (if (null root)
       nil
     (avl-tree--node-create
   (if (null root)
       nil
     (avl-tree--node-create


@@ -401,7 +411,7 @@ itself."
   ;; front of the STACK, until a leaf is reached.
   (let ((node (car (avl-tree--stack-store stack)))
        (dir (if (avl-tree--stack-reverse stack) 1 0)))
   ;; front of the STACK, until a leaf is reached.
   (let ((node (car (avl-tree--stack-store stack)))
        (dir (if (avl-tree--stack-reverse stack) 1 0)))

-    (when node  ; check for emtpy stack
+    (when node  ; check for empty stack

       (while (setq node (avl-tree--node-branch node dir))
        (push node (avl-tree--stack-store stack))))))
 
       (while (setq node (avl-tree--node-branch node dir))
        (push node (avl-tree--stack-store stack))))))
 


@@ -411,21 +421,21 @@ itself."
 
 ;; define public alias for constructors so that we can set docstring
 (defalias 'avl-tree-create 'avl-tree--create
 
 ;; define public alias for constructors so that we can set docstring
 (defalias 'avl-tree-create 'avl-tree--create

-  "Create an empty avl tree.
+  "Create an empty AVL tree.

 COMPARE-FUNCTION is a function which takes two arguments, A and B,
 and returns non-nil if A is less than B, and nil otherwise.")
 
 (defalias 'avl-tree-compare-function 'avl-tree--cmpfun
 COMPARE-FUNCTION is a function which takes two arguments, A and B,
 and returns non-nil if A is less than B, and nil otherwise.")
 
 (defalias 'avl-tree-compare-function 'avl-tree--cmpfun

-  "Return the comparison function for the avl tree TREE.
+  "Return the comparison function for the AVL tree TREE.

 
 \(fn TREE)")
 
 (defun avl-tree-empty (tree)
 
 \(fn TREE)")
 
 (defun avl-tree-empty (tree)

-  "Return t if avl tree TREE is emtpy, otherwise return nil."
+  "Return t if AVL tree TREE is empty, otherwise return nil."

   (null (avl-tree--root tree)))
 
 (defun avl-tree-enter (tree data &optional updatefun)
   (null (avl-tree--root tree)))
 
 (defun avl-tree-enter (tree data &optional updatefun)

-  "Insert DATA into the avl tree TREE.
+  "Insert DATA into the AVL tree TREE.

 
 If an element that matches DATA (according to the tree's
 comparison function, see `avl-tree-create') already exists in
 
 If an element that matches DATA (according to the tree's
 comparison function, see `avl-tree-create') already exists in


@@ -433,8 +443,8 @@ TREE, it will be replaced by DATA by default.
 
 If UPDATEFUN is supplied and an element matching DATA already
 exists in TREE, UPDATEFUN is called with two arguments: DATA, and
 
 If UPDATEFUN is supplied and an element matching DATA already
 exists in TREE, UPDATEFUN is called with two arguments: DATA, and

-the matching element. Its return value replaces the existing
-element. This value *must* itself match DATA (and hence the
+the matching element.  Its return value replaces the existing
+element.  This value *must* itself match DATA (and hence the

 pre-existing data), or an error will occur.
 
 Returns the new data."
 pre-existing data), or an error will occur.
 
 Returns the new data."


@@ -443,7 +453,7 @@ Returns the new data."
                           0 data updatefun)))
 
 (defun avl-tree-delete (tree data &optional test nilflag)
                           0 data updatefun)))
 
 (defun avl-tree-delete (tree data &optional test nilflag)

-  "Delete the element matching DATA from the avl tree TREE.
+  "Delete the element matching DATA from the AVL tree TREE.

 Matching uses the comparison function previously specified in
 `avl-tree-create' when TREE was created.
 
 Matching uses the comparison function previously specified in
 `avl-tree-create' when TREE was created.
 


@@ -456,7 +466,7 @@ distinguished from the case of a successfully deleted null
 element.
 
 If supplied, TEST specifies a test that a matching element must
 element.
 
 If supplied, TEST specifies a test that a matching element must

-pass before it is deleted. If a matching element is found, it is
+pass before it is deleted.  If a matching element is found, it is

 passed as an argument to TEST, and is deleted only if the return
 value is non-nil."
   (cdr (avl-tree--do-delete (avl-tree--cmpfun tree)
 passed as an argument to TEST, and is deleted only if the return
 value is non-nil."
   (cdr (avl-tree--do-delete (avl-tree--cmpfun tree)


@@ -465,14 +475,14 @@ value is non-nil."
 
 
 (defun avl-tree-member (tree data &optional nilflag)
 
 
 (defun avl-tree-member (tree data &optional nilflag)

-  "Return the element in the avl tree TREE which matches DATA.
+  "Return the element in the AVL tree TREE which matches DATA.

 Matching uses the comparison function previously specified in
 `avl-tree-create' when TREE was created.
 
 If there is no such element in the tree, nil is
 Matching uses the comparison function previously specified in
 `avl-tree-create' when TREE was created.
 
 If there is no such element in the tree, nil is

-returned. Optional argument NILFLAG specifies a value to return
-instead of nil in this case. This allows non-existent elements to
-be distinguished from a null element. (See also
+returned.  Optional argument NILFLAG specifies a value to return
+instead of nil in this case.  This allows non-existent elements to
+be distinguished from a null element.  (See also

 `avl-tree-member-p', which does this for you.)"
   (let ((node (avl-tree--root tree))
        (compare-function (avl-tree--cmpfun tree)))
 `avl-tree-member-p', which does this for you.)"
   (let ((node (avl-tree--root tree))
        (compare-function (avl-tree--cmpfun tree)))


@@ -488,15 +498,15 @@ be distinguished from a null element. (See also
 
 
 (defun avl-tree-member-p (tree data)
 
 
 (defun avl-tree-member-p (tree data)

-  "Return t if an element matching DATA exists in the avl tree TREE,
-otherwise return nil. Matching uses the comparison function
+  "Return t if an element matching DATA exists in the AVL tree TREE.
+Otherwise return nil.  Matching uses the comparison function

 previously specified in `avl-tree-create' when TREE was created."
   (let ((flag '(nil)))
     (not (eq (avl-tree-member tree data flag) flag))))
 
 
 (defun avl-tree-map (__map-function__ tree &optional reverse)
 previously specified in `avl-tree-create' when TREE was created."
   (let ((flag '(nil)))
     (not (eq (avl-tree-member tree data flag) flag))))
 
 
 (defun avl-tree-map (__map-function__ tree &optional reverse)

-  "Modify all elements in the avl tree TREE by applying FUNCTION.
+  "Modify all elements in the AVL tree TREE by applying FUNCTION.

 
 Each element is replaced by the return value of FUNCTION applied
 to that element.
 
 Each element is replaced by the return value of FUNCTION applied
 to that element.


@@ -512,7 +522,7 @@ descending order if REVERSE is non-nil."
 
 
 (defun avl-tree-mapc (__map-function__ tree &optional reverse)
 
 
 (defun avl-tree-mapc (__map-function__ tree &optional reverse)

-  "Apply FUNCTION to all elements in avl tree TREE,
+  "Apply FUNCTION to all elements in AVL tree TREE,

 for side-effect only.
 
 FUNCTION is applied to the elements in ascending order, or
 for side-effect only.
 
 FUNCTION is applied to the elements in ascending order, or


@@ -526,7 +536,7 @@ descending order if REVERSE is non-nil."
 
 (defun avl-tree-mapf
   (__map-function__ combinator tree &optional reverse)
 
 (defun avl-tree-mapf
   (__map-function__ combinator tree &optional reverse)

-  "Apply FUNCTION to all elements in avl tree TREE,
+  "Apply FUNCTION to all elements in AVL tree TREE,

 and combine the results using COMBINATOR.
 
 The FUNCTION is applied and the results are combined in ascending
 and combine the results using COMBINATOR.
 
 The FUNCTION is applied and the results are combined in ascending


@@ -545,7 +555,7 @@ order, or descending order if REVERSE is non-nil."
 
 
 (defun avl-tree-mapcar (__map-function__ tree &optional reverse)
 
 
 (defun avl-tree-mapcar (__map-function__ tree &optional reverse)

-  "Apply FUNCTION to all elements in avl tree TREE,
+  "Apply FUNCTION to all elements in AVL tree TREE,

 and make a list of the results.
 
 The FUNCTION is applied and the list constructed in ascending
 and make a list of the results.
 
 The FUNCTION is applied and the list constructed in ascending


@@ -578,7 +588,7 @@ is more efficient."
       (avl-tree--node-data node))))
 
 (defun avl-tree-copy (tree)
       (avl-tree--node-data node))))
 
 (defun avl-tree-copy (tree)

-  "Return a copy of the avl tree TREE."
+  "Return a copy of the AVL tree TREE."

   (let ((new-tree (avl-tree-create (avl-tree--cmpfun tree))))
     (setf (avl-tree--root new-tree) (avl-tree--do-copy (avl-tree--root tree)))
     new-tree))
   (let ((new-tree (avl-tree-create (avl-tree--cmpfun tree))))
     (setf (avl-tree--root new-tree) (avl-tree--do-copy (avl-tree--root tree)))
     new-tree))


@@ -600,7 +610,7 @@ is more efficient."
     treesize))
 
 (defun avl-tree-clear (tree)
     treesize))
 
 (defun avl-tree-clear (tree)

-  "Clear the avl tree TREE."
+  "Clear the AVL tree TREE."

   (setf (avl-tree--root tree) nil))
 
 
   (setf (avl-tree--root tree) nil))
 
 


@@ -617,8 +627,8 @@ calling `avl-tree-stack-pop' will give unpredictable results).
 
 Operations on these objects are significantly more efficient than
 constructing a real stack with `avl-tree-flatten' and using
 
 Operations on these objects are significantly more efficient than
 constructing a real stack with `avl-tree-flatten' and using

-standard stack functions. As such, they can be useful in
-implementing efficient algorithms of AVL trees. However, in cases
+standard stack functions.  As such, they can be useful in
+implementing efficient algorithms of AVL trees.  However, in cases

 where mapping functions `avl-tree-mapc', `avl-tree-mapcar' or
 `avl-tree-mapf' would be sufficient, it is better to use one of
 those instead."
 where mapping functions `avl-tree-mapc', `avl-tree-mapcar' or
 `avl-tree-mapf' would be sufficient, it is better to use one of
 those instead."


@@ -629,11 +639,11 @@ those instead."
 
 (defun avl-tree-stack-pop (avl-tree-stack &optional nilflag)
   "Pop the first element from AVL-TREE-STACK.
 
 (defun avl-tree-stack-pop (avl-tree-stack &optional nilflag)
   "Pop the first element from AVL-TREE-STACK.

-\(See also `avl-tree-stack'\).
+\(See also `avl-tree-stack').

 
 

-Returns nil if the stack is empty, or NILFLAG if specified. (The
-latter allows an empty stack to be distinguished from a null
-element stored in the AVL tree.)"
+Returns nil if the stack is empty, or NILFLAG if specified.
+\(The latter allows an empty stack to be distinguished from
+a null element stored in the AVL tree.)"

   (let (node next)
     (if (not (setq node (pop (avl-tree--stack-store avl-tree-stack))))
        nilflag
   (let (node next)
     (if (not (setq node (pop (avl-tree--stack-store avl-tree-stack))))
        nilflag


@@ -650,9 +660,9 @@ element stored in the AVL tree.)"
   "Return the first element of AVL-TREE-STACK, without removing it
 from the stack.
 
   "Return the first element of AVL-TREE-STACK, without removing it
 from the stack.
 

-Returns nil if the stack is empty, or NILFLAG if specified. (The
-latter allows an empty stack to be distinguished from a null
-element stored in the AVL tree.)"
+Returns nil if the stack is empty, or NILFLAG if specified.
+\(The latter allows an empty stack to be distinguished from
+a null element stored in the AVL tree.)"

   (or (car (avl-tree--stack-store avl-tree-stack))
       nilflag))
 
   (or (car (avl-tree--stack-store avl-tree-stack))
       nilflag))