diff lisp/cl-seq.el @ 428:3ecd8885ac67 r21-2-22

Import from CVS: tag r21-2-22
author cvs
date Mon, 13 Aug 2007 11:28:15 +0200
parents
children abe6d1db359e
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lisp/cl-seq.el	Mon Aug 13 11:28:15 2007 +0200
@@ -0,0 +1,938 @@
+;;; cl-seq.el --- Common Lisp extensions for GNU Emacs Lisp (part three)
+
+;; Copyright (C) 1993 Free Software Foundation, Inc.
+
+;; Author: Dave Gillespie <daveg@synaptics.com>
+;; Maintainer: XEmacs Development Team
+;; Version: 2.02
+;; Keywords: extensions, dumped
+
+;; This file is part of XEmacs.
+
+;; XEmacs is free software; you can redistribute it and/or modify it
+;; under the terms of the GNU General Public License as published by
+;; the Free Software Foundation; either version 2, or (at your option)
+;; any later version.
+
+;; XEmacs is distributed in the hope that it will be useful, but
+;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+;; General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with XEmacs; see the file COPYING.  If not, write to the Free
+;; Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+;; 02111-1307, USA.
+
+;;; Synched up with: FSF 19.34.
+
+;;; Commentary:
+
+;; This file is dumped with XEmacs.
+
+;; These are extensions to Emacs Lisp that provide a degree of
+;; Common Lisp compatibility, beyond what is already built-in
+;; in Emacs Lisp.
+;;
+;; This package was written by Dave Gillespie; it is a complete
+;; rewrite of Cesar Quiroz's original cl.el package of December 1986.
+;;
+;; This package works with Emacs 18, Emacs 19, and Lucid Emacs 19.
+;;
+;; Bug reports, comments, and suggestions are welcome!
+
+;; This file contains the Common Lisp sequence and list functions
+;; which take keyword arguments.
+
+;; See cl.el for Change Log.
+
+
+;;; Code:
+
+(or (memq 'cl-19 features)
+    (error "Tried to load `cl-seq' before `cl'!"))
+
+
+;;; We define these here so that this file can compile without having
+;;; loaded the cl.el file already.
+
+(defmacro cl-push (x place) (list 'setq place (list 'cons x place)))
+(defmacro cl-pop (place)
+  (list 'car (list 'prog1 place (list 'setq place (list 'cdr place)))))
+
+
+;;; Keyword parsing.  This is special-cased here so that we can compile
+;;; this file independent from cl-macs.
+
+(defmacro cl-parsing-keywords (kwords other-keys &rest body)
+  (cons
+   'let*
+   (cons (mapcar
+	  (function
+	   (lambda (x)
+	     (let* ((var (if (consp x) (car x) x))
+		    (mem (list 'car (list 'cdr (list 'memq (list 'quote var)
+						     'cl-keys)))))
+	       (if (eq var ':test-not)
+		   (setq mem (list 'and mem (list 'setq 'cl-test mem) t)))
+	       (if (eq var ':if-not)
+		   (setq mem (list 'and mem (list 'setq 'cl-if mem) t)))
+	       (list (intern
+		      (format "cl-%s" (substring (symbol-name var) 1)))
+		     (if (consp x) (list 'or mem (car (cdr x))) mem)))))
+	  kwords)
+	 (append
+	  (and (not (eq other-keys t))
+	       (list
+		(list 'let '((cl-keys-temp cl-keys))
+		      (list 'while 'cl-keys-temp
+			    (list 'or (list 'memq '(car cl-keys-temp)
+					    (list 'quote
+						  (mapcar
+						   (function
+						    (lambda (x)
+						      (if (consp x)
+							  (car x) x)))
+						   (append kwords
+							   other-keys))))
+				  '(car (cdr (memq (quote :allow-other-keys)
+						   cl-keys)))
+				  '(error "Bad keyword argument %s"
+					  (car cl-keys-temp)))
+			    '(setq cl-keys-temp (cdr (cdr cl-keys-temp)))))))
+	  body))))
+(put 'cl-parsing-keywords 'lisp-indent-function 2)
+(put 'cl-parsing-keywords 'edebug-form-spec '(sexp sexp &rest form))
+
+(defmacro cl-check-key (x)
+  (list 'if 'cl-key (list 'funcall 'cl-key x) x))
+
+(defmacro cl-check-test-nokey (item x)
+  (list 'cond
+	(list 'cl-test
+	      (list 'eq (list 'not (list 'funcall 'cl-test item x))
+		    'cl-test-not))
+	(list 'cl-if
+	      (list 'eq (list 'not (list 'funcall 'cl-if x)) 'cl-if-not))
+	(list 't (list 'if (list 'numberp item)
+		       (list 'equal item x) (list 'eq item x)))))
+
+(defmacro cl-check-test (item x)
+  (list 'cl-check-test-nokey item (list 'cl-check-key x)))
+
+(defmacro cl-check-match (x y)
+  (setq x (list 'cl-check-key x) y (list 'cl-check-key y))
+  (list 'if 'cl-test
+	(list 'eq (list 'not (list 'funcall 'cl-test x y)) 'cl-test-not)
+	(list 'if (list 'numberp x)
+	      (list 'equal x y) (list 'eq x y))))
+
+(put 'cl-check-key 'edebug-form-spec 'edebug-forms)
+(put 'cl-check-test 'edebug-form-spec 'edebug-forms)
+(put 'cl-check-test-nokey 'edebug-form-spec 'edebug-forms)
+(put 'cl-check-match 'edebug-form-spec 'edebug-forms)
+
+(defvar cl-test) (defvar cl-test-not)
+(defvar cl-if) (defvar cl-if-not)
+(defvar cl-key)
+
+
+(defun reduce (cl-func cl-seq &rest cl-keys)
+  "Reduce two-argument FUNCTION across SEQUENCE.
+Keywords supported:  :start :end :from-end :initial-value :key"
+  (cl-parsing-keywords (:from-end (:start 0) :end :initial-value :key) ()
+    (or (listp cl-seq) (setq cl-seq (append cl-seq nil)))
+    (setq cl-seq (subseq cl-seq cl-start cl-end))
+    (if cl-from-end (setq cl-seq (nreverse cl-seq)))
+    (let ((cl-accum (cond ((memq ':initial-value cl-keys) cl-initial-value)
+			  (cl-seq (cl-check-key (cl-pop cl-seq)))
+			  (t (funcall cl-func)))))
+      (if cl-from-end
+	  (while cl-seq
+	    (setq cl-accum (funcall cl-func (cl-check-key (cl-pop cl-seq))
+				    cl-accum)))
+	(while cl-seq
+	  (setq cl-accum (funcall cl-func cl-accum
+				  (cl-check-key (cl-pop cl-seq))))))
+      cl-accum)))
+
+(defun fill (seq item &rest cl-keys)
+  "Fill the elements of SEQ with ITEM.
+Keywords supported:  :start :end"
+  (cl-parsing-keywords ((:start 0) :end) ()
+    (if (listp seq)
+	(let ((p (nthcdr cl-start seq))
+	      (n (if cl-end (- cl-end cl-start) 8000000)))
+	  (while (and p (>= (setq n (1- n)) 0))
+	    (setcar p item)
+	    (setq p (cdr p))))
+      (or cl-end (setq cl-end (length seq)))
+      (if (and (= cl-start 0) (= cl-end (length seq)))
+	  (fillarray seq item)
+	(while (< cl-start cl-end)
+	  (aset seq cl-start item)
+	  (setq cl-start (1+ cl-start)))))
+    seq))
+
+(defun replace (cl-seq1 cl-seq2 &rest cl-keys)
+  "Replace the elements of SEQ1 with the elements of SEQ2.
+SEQ1 is destructively modified, then returned.
+Keywords supported:  :start1 :end1 :start2 :end2"
+  (cl-parsing-keywords ((:start1 0) :end1 (:start2 0) :end2) ()
+    (if (and (eq cl-seq1 cl-seq2) (<= cl-start2 cl-start1))
+	(or (= cl-start1 cl-start2)
+	    (let* ((cl-len (length cl-seq1))
+		   (cl-n (min (- (or cl-end1 cl-len) cl-start1)
+			      (- (or cl-end2 cl-len) cl-start2))))
+	      (while (>= (setq cl-n (1- cl-n)) 0)
+		(cl-set-elt cl-seq1 (+ cl-start1 cl-n)
+			    (elt cl-seq2 (+ cl-start2 cl-n))))))
+      (if (listp cl-seq1)
+	  (let ((cl-p1 (nthcdr cl-start1 cl-seq1))
+		(cl-n1 (if cl-end1 (- cl-end1 cl-start1) 4000000)))
+	    (if (listp cl-seq2)
+		(let ((cl-p2 (nthcdr cl-start2 cl-seq2))
+		      (cl-n (min cl-n1
+				 (if cl-end2 (- cl-end2 cl-start2) 4000000))))
+		  (while (and cl-p1 cl-p2 (>= (setq cl-n (1- cl-n)) 0))
+		    (setcar cl-p1 (car cl-p2))
+		    (setq cl-p1 (cdr cl-p1) cl-p2 (cdr cl-p2))))
+	      (setq cl-end2 (min (or cl-end2 (length cl-seq2))
+				 (+ cl-start2 cl-n1)))
+	      (while (and cl-p1 (< cl-start2 cl-end2))
+		(setcar cl-p1 (aref cl-seq2 cl-start2))
+		(setq cl-p1 (cdr cl-p1) cl-start2 (1+ cl-start2)))))
+	(setq cl-end1 (min (or cl-end1 (length cl-seq1))
+			   (+ cl-start1 (- (or cl-end2 (length cl-seq2))
+					   cl-start2))))
+	(if (listp cl-seq2)
+	    (let ((cl-p2 (nthcdr cl-start2 cl-seq2)))
+	      (while (< cl-start1 cl-end1)
+		(aset cl-seq1 cl-start1 (car cl-p2))
+		(setq cl-p2 (cdr cl-p2) cl-start1 (1+ cl-start1))))
+	  (while (< cl-start1 cl-end1)
+	    (aset cl-seq1 cl-start1 (aref cl-seq2 cl-start2))
+	    (setq cl-start2 (1+ cl-start2) cl-start1 (1+ cl-start1))))))
+    cl-seq1))
+
+(defun remove* (cl-item cl-seq &rest cl-keys)
+  "Remove all occurrences of ITEM in SEQ.
+This is a non-destructive function; it makes a copy of SEQ if necessary
+to avoid corrupting the original SEQ.
+Keywords supported:  :test :test-not :key :count :start :end :from-end"
+  (cl-parsing-keywords (:test :test-not :key :if :if-not :count :from-end
+			(:start 0) :end) ()
+    (if (<= (or cl-count (setq cl-count 8000000)) 0)
+	cl-seq
+      (if (or (nlistp cl-seq) (and cl-from-end (< cl-count 4000000)))
+	  (let ((cl-i (cl-position cl-item cl-seq cl-start cl-end
+				   cl-from-end)))
+	    (if cl-i
+		(let ((cl-res (apply 'delete* cl-item (append cl-seq nil)
+				     (append (if cl-from-end
+						 (list ':end (1+ cl-i))
+					       (list ':start cl-i))
+					     cl-keys))))
+		  (if (listp cl-seq) cl-res
+		    (if (stringp cl-seq) (concat cl-res) (vconcat cl-res))))
+	      cl-seq))
+	(setq cl-end (- (or cl-end 8000000) cl-start))
+	(if (= cl-start 0)
+	    (while (and cl-seq (> cl-end 0)
+			(cl-check-test cl-item (car cl-seq))
+			(setq cl-end (1- cl-end) cl-seq (cdr cl-seq))
+			(> (setq cl-count (1- cl-count)) 0))))
+	(if (and (> cl-count 0) (> cl-end 0))
+	    (let ((cl-p (if (> cl-start 0) (nthcdr cl-start cl-seq)
+			  (setq cl-end (1- cl-end)) (cdr cl-seq))))
+	      (while (and cl-p (> cl-end 0)
+			  (not (cl-check-test cl-item (car cl-p))))
+		(setq cl-p (cdr cl-p) cl-end (1- cl-end)))
+	      (if (and cl-p (> cl-end 0))
+		  (nconc (ldiff cl-seq cl-p)
+			 (if (= cl-count 1) (cdr cl-p)
+			   (and (cdr cl-p)
+				(apply 'delete* cl-item
+				       (copy-sequence (cdr cl-p))
+				       ':start 0 ':end (1- cl-end)
+				       ':count (1- cl-count) cl-keys))))
+		cl-seq))
+	  cl-seq)))))
+
+(defun remove-if (cl-pred cl-list &rest cl-keys)
+  "Remove all items satisfying PREDICATE in SEQ.
+This is a non-destructive function; it makes a copy of SEQ if necessary
+to avoid corrupting the original SEQ.
+Keywords supported:  :key :count :start :end :from-end"
+  (apply 'remove* nil cl-list ':if cl-pred cl-keys))
+
+(defun remove-if-not (cl-pred cl-list &rest cl-keys)
+  "Remove all items not satisfying PREDICATE in SEQ.
+This is a non-destructive function; it makes a copy of SEQ if necessary
+to avoid corrupting the original SEQ.
+Keywords supported:  :key :count :start :end :from-end"
+  (apply 'remove* nil cl-list ':if-not cl-pred cl-keys))
+
+(defun delete* (cl-item cl-seq &rest cl-keys)
+  "Remove all occurrences of ITEM in SEQ.
+This is a destructive function; it reuses the storage of SEQ whenever possible.
+Keywords supported:  :test :test-not :key :count :start :end :from-end"
+  (cl-parsing-keywords (:test :test-not :key :if :if-not :count :from-end
+			(:start 0) :end) ()
+    (if (<= (or cl-count (setq cl-count 8000000)) 0)
+	cl-seq
+      (if (listp cl-seq)
+	  (if (and cl-from-end (< cl-count 4000000))
+	      (let (cl-i)
+		(while (and (>= (setq cl-count (1- cl-count)) 0)
+			    (setq cl-i (cl-position cl-item cl-seq cl-start
+						    cl-end cl-from-end)))
+		  (if (= cl-i 0) (setq cl-seq (cdr cl-seq))
+		    (let ((cl-tail (nthcdr (1- cl-i) cl-seq)))
+		      (setcdr cl-tail (cdr (cdr cl-tail)))))
+		  (setq cl-end cl-i))
+		cl-seq)
+	    (setq cl-end (- (or cl-end 8000000) cl-start))
+	    (if (= cl-start 0)
+		(progn
+		  (while (and cl-seq
+			      (> cl-end 0)
+			      (cl-check-test cl-item (car cl-seq))
+			      (setq cl-end (1- cl-end) cl-seq (cdr cl-seq))
+			      (> (setq cl-count (1- cl-count)) 0)))
+		  (setq cl-end (1- cl-end)))
+	      (setq cl-start (1- cl-start)))
+	    (if (and (> cl-count 0) (> cl-end 0))
+		(let ((cl-p (nthcdr cl-start cl-seq)))
+		  (while (and (cdr cl-p) (> cl-end 0))
+		    (if (cl-check-test cl-item (car (cdr cl-p)))
+			(progn
+			  (setcdr cl-p (cdr (cdr cl-p)))
+			  (if (= (setq cl-count (1- cl-count)) 0)
+			      (setq cl-end 1)))
+		      (setq cl-p (cdr cl-p)))
+		    (setq cl-end (1- cl-end)))))
+	    cl-seq)
+	(apply 'remove* cl-item cl-seq cl-keys)))))
+
+(defun delete-if (cl-pred cl-list &rest cl-keys)
+  "Remove all items satisfying PREDICATE in SEQ.
+This is a destructive function; it reuses the storage of SEQ whenever possible.
+Keywords supported:  :key :count :start :end :from-end"
+  (apply 'delete* nil cl-list ':if cl-pred cl-keys))
+
+(defun delete-if-not (cl-pred cl-list &rest cl-keys)
+  "Remove all items not satisfying PREDICATE in SEQ.
+This is a destructive function; it reuses the storage of SEQ whenever possible.
+Keywords supported:  :key :count :start :end :from-end"
+  (apply 'delete* nil cl-list ':if-not cl-pred cl-keys))
+
+(or (and (fboundp 'delete) (subrp (symbol-function 'delete)))
+    (defalias 'delete (function (lambda (x y) (delete* x y ':test 'equal)))))
+
+(defun remove (cl-item cl-seq)
+  "Remove all occurrences of ITEM in SEQ, testing with `equal'
+This is a non-destructive function; it makes a copy of SEQ if necessary
+to avoid corrupting the original SEQ.
+Also see: `remove*', `delete', `delete*'"
+  (remove* cl-item cl-seq ':test 'equal))
+
+(defun remq (cl-elt cl-list)
+  "Remove all occurances of ELT in LIST, comparing with `eq'.
+This is a non-destructive function; it makes a copy of LIST to avoid
+corrupting the original LIST.
+Also see: `delq', `delete', `delete*', `remove', `remove*'."
+  (if (memq cl-elt cl-list)
+      (delq cl-elt (copy-list cl-list))
+    cl-list))
+
+(defun remove-duplicates (cl-seq &rest cl-keys)
+  "Return a copy of SEQ with all duplicate elements removed.
+Keywords supported:  :test :test-not :key :start :end :from-end"
+  (cl-delete-duplicates cl-seq cl-keys t))
+
+(defun delete-duplicates (cl-seq &rest cl-keys)
+  "Remove all duplicate elements from SEQ (destructively).
+Keywords supported:  :test :test-not :key :start :end :from-end"
+  (cl-delete-duplicates cl-seq cl-keys nil))
+
+(defun cl-delete-duplicates (cl-seq cl-keys cl-copy)
+  (if (listp cl-seq)
+      (cl-parsing-keywords (:test :test-not :key (:start 0) :end :from-end :if)
+	  ()
+	(if cl-from-end
+	    (let ((cl-p (nthcdr cl-start cl-seq)) cl-i)
+	      (setq cl-end (- (or cl-end (length cl-seq)) cl-start))
+	      (while (> cl-end 1)
+		(setq cl-i 0)
+		(while (setq cl-i (cl-position (cl-check-key (car cl-p))
+					       (cdr cl-p) cl-i (1- cl-end)))
+		  (if cl-copy (setq cl-seq (copy-sequence cl-seq)
+				    cl-p (nthcdr cl-start cl-seq) cl-copy nil))
+		  (let ((cl-tail (nthcdr cl-i cl-p)))
+		    (setcdr cl-tail (cdr (cdr cl-tail))))
+		  (setq cl-end (1- cl-end)))
+		(setq cl-p (cdr cl-p) cl-end (1- cl-end)
+		      cl-start (1+ cl-start)))
+	      cl-seq)
+	  (setq cl-end (- (or cl-end (length cl-seq)) cl-start))
+	  (while (and (cdr cl-seq) (= cl-start 0) (> cl-end 1)
+		      (cl-position (cl-check-key (car cl-seq))
+				   (cdr cl-seq) 0 (1- cl-end)))
+	    (setq cl-seq (cdr cl-seq) cl-end (1- cl-end)))
+	  (let ((cl-p (if (> cl-start 0) (nthcdr (1- cl-start) cl-seq)
+			(setq cl-end (1- cl-end) cl-start 1) cl-seq)))
+	    (while (and (cdr (cdr cl-p)) (> cl-end 1))
+	      (if (cl-position (cl-check-key (car (cdr cl-p)))
+			       (cdr (cdr cl-p)) 0 (1- cl-end))
+		  (progn
+		    (if cl-copy (setq cl-seq (copy-sequence cl-seq)
+				      cl-p (nthcdr (1- cl-start) cl-seq)
+				      cl-copy nil))
+		    (setcdr cl-p (cdr (cdr cl-p))))
+		(setq cl-p (cdr cl-p)))
+	      (setq cl-end (1- cl-end) cl-start (1+ cl-start)))
+	    cl-seq)))
+    (let ((cl-res (cl-delete-duplicates (append cl-seq nil) cl-keys nil)))
+      (if (stringp cl-seq) (concat cl-res) (vconcat cl-res)))))
+
+(defun substitute (cl-new cl-old cl-seq &rest cl-keys)
+  "Substitute NEW for OLD in SEQ.
+This is a non-destructive function; it makes a copy of SEQ if necessary
+to avoid corrupting the original SEQ.
+Keywords supported:  :test :test-not :key :count :start :end :from-end"
+  (cl-parsing-keywords (:test :test-not :key :if :if-not :count
+			(:start 0) :end :from-end) ()
+    (if (or (eq cl-old cl-new)
+	    (<= (or cl-count (setq cl-from-end nil cl-count 8000000)) 0))
+	cl-seq
+      (let ((cl-i (cl-position cl-old cl-seq cl-start cl-end)))
+	(if (not cl-i)
+	    cl-seq
+	  (setq cl-seq (copy-sequence cl-seq))
+	  (or cl-from-end
+	      (progn (cl-set-elt cl-seq cl-i cl-new)
+		     (setq cl-i (1+ cl-i) cl-count (1- cl-count))))
+	  (apply 'nsubstitute cl-new cl-old cl-seq ':count cl-count
+		 ':start cl-i cl-keys))))))
+
+(defun substitute-if (cl-new cl-pred cl-list &rest cl-keys)
+  "Substitute NEW for all items satisfying PREDICATE in SEQ.
+This is a non-destructive function; it makes a copy of SEQ if necessary
+to avoid corrupting the original SEQ.
+Keywords supported:  :key :count :start :end :from-end"
+  (apply 'substitute cl-new nil cl-list ':if cl-pred cl-keys))
+
+(defun substitute-if-not (cl-new cl-pred cl-list &rest cl-keys)
+  "Substitute NEW for all items not satisfying PREDICATE in SEQ.
+This is a non-destructive function; it makes a copy of SEQ if necessary
+to avoid corrupting the original SEQ.
+Keywords supported:  :key :count :start :end :from-end"
+  (apply 'substitute cl-new nil cl-list ':if-not cl-pred cl-keys))
+
+(defun nsubstitute (cl-new cl-old cl-seq &rest cl-keys)
+  "Substitute NEW for OLD in SEQ.
+This is a destructive function; it reuses the storage of SEQ whenever possible.
+Keywords supported:  :test :test-not :key :count :start :end :from-end"
+  (cl-parsing-keywords (:test :test-not :key :if :if-not :count
+			(:start 0) :end :from-end) ()
+    (or (eq cl-old cl-new) (<= (or cl-count (setq cl-count 8000000)) 0)
+	(if (and (listp cl-seq) (or (not cl-from-end) (> cl-count 4000000)))
+	    (let ((cl-p (nthcdr cl-start cl-seq)))
+	      (setq cl-end (- (or cl-end 8000000) cl-start))
+	      (while (and cl-p (> cl-end 0) (> cl-count 0))
+		(if (cl-check-test cl-old (car cl-p))
+		    (progn
+		      (setcar cl-p cl-new)
+		      (setq cl-count (1- cl-count))))
+		(setq cl-p (cdr cl-p) cl-end (1- cl-end))))
+	  (or cl-end (setq cl-end (length cl-seq)))
+	  (if cl-from-end
+	      (while (and (< cl-start cl-end) (> cl-count 0))
+		(setq cl-end (1- cl-end))
+		(if (cl-check-test cl-old (elt cl-seq cl-end))
+		    (progn
+		      (cl-set-elt cl-seq cl-end cl-new)
+		      (setq cl-count (1- cl-count)))))
+	    (while (and (< cl-start cl-end) (> cl-count 0))
+	      (if (cl-check-test cl-old (aref cl-seq cl-start))
+		  (progn
+		    (aset cl-seq cl-start cl-new)
+		    (setq cl-count (1- cl-count))))
+	      (setq cl-start (1+ cl-start))))))
+    cl-seq))
+
+(defun nsubstitute-if (cl-new cl-pred cl-list &rest cl-keys)
+  "Substitute NEW for all items satisfying PREDICATE in SEQ.
+This is a destructive function; it reuses the storage of SEQ whenever possible.
+Keywords supported:  :key :count :start :end :from-end"
+  (apply 'nsubstitute cl-new nil cl-list ':if cl-pred cl-keys))
+
+(defun nsubstitute-if-not (cl-new cl-pred cl-list &rest cl-keys)
+  "Substitute NEW for all items not satisfying PREDICATE in SEQ.
+This is a destructive function; it reuses the storage of SEQ whenever possible.
+Keywords supported:  :key :count :start :end :from-end"
+  (apply 'nsubstitute cl-new nil cl-list ':if-not cl-pred cl-keys))
+
+(defun find (cl-item cl-seq &rest cl-keys)
+  "Find the first occurrence of ITEM in LIST.
+Return the matching ITEM, or nil if not found.
+Keywords supported:  :test :test-not :key :start :end :from-end"
+  (let ((cl-pos (apply 'position cl-item cl-seq cl-keys)))
+    (and cl-pos (elt cl-seq cl-pos))))
+
+(defun find-if (cl-pred cl-list &rest cl-keys)
+  "Find the first item satisfying PREDICATE in LIST.
+Return the matching ITEM, or nil if not found.
+Keywords supported:  :key :start :end :from-end"
+  (apply 'find nil cl-list ':if cl-pred cl-keys))
+
+(defun find-if-not (cl-pred cl-list &rest cl-keys)
+  "Find the first item not satisfying PREDICATE in LIST.
+Return the matching ITEM, or nil if not found.
+Keywords supported:  :key :start :end :from-end"
+  (apply 'find nil cl-list ':if-not cl-pred cl-keys))
+
+(defun position (cl-item cl-seq &rest cl-keys)
+  "Find the first occurrence of ITEM in LIST.
+Return the index of the matching item, or nil if not found.
+Keywords supported:  :test :test-not :key :start :end :from-end"
+  (cl-parsing-keywords (:test :test-not :key :if :if-not
+			(:start 0) :end :from-end) ()
+    (cl-position cl-item cl-seq cl-start cl-end cl-from-end)))
+
+(defun cl-position (cl-item cl-seq cl-start &optional cl-end cl-from-end)
+  (if (listp cl-seq)
+      (let ((cl-p (nthcdr cl-start cl-seq)))
+	(or cl-end (setq cl-end 8000000))
+	(let ((cl-res nil))
+	  (while (and cl-p (< cl-start cl-end) (or (not cl-res) cl-from-end))
+	    (if (cl-check-test cl-item (car cl-p))
+		(setq cl-res cl-start))
+	    (setq cl-p (cdr cl-p) cl-start (1+ cl-start)))
+	  cl-res))
+    (or cl-end (setq cl-end (length cl-seq)))
+    (if cl-from-end
+	(progn
+	  (while (and (>= (setq cl-end (1- cl-end)) cl-start)
+		      (not (cl-check-test cl-item (aref cl-seq cl-end)))))
+	  (and (>= cl-end cl-start) cl-end))
+      (while (and (< cl-start cl-end)
+		  (not (cl-check-test cl-item (aref cl-seq cl-start))))
+	(setq cl-start (1+ cl-start)))
+      (and (< cl-start cl-end) cl-start))))
+
+(defun position-if (cl-pred cl-list &rest cl-keys)
+  "Find the first item satisfying PREDICATE in LIST.
+Return the index of the matching item, or nil if not found.
+Keywords supported:  :key :start :end :from-end"
+  (apply 'position nil cl-list ':if cl-pred cl-keys))
+
+(defun position-if-not (cl-pred cl-list &rest cl-keys)
+  "Find the first item not satisfying PREDICATE in LIST.
+Return the index of the matching item, or nil if not found.
+Keywords supported:  :key :start :end :from-end"
+  (apply 'position nil cl-list ':if-not cl-pred cl-keys))
+
+(defun count (cl-item cl-seq &rest cl-keys)
+  "Count the number of occurrences of ITEM in LIST.
+Keywords supported:  :test :test-not :key :start :end"
+  (cl-parsing-keywords (:test :test-not :key :if :if-not (:start 0) :end) ()
+    (let ((cl-count 0) cl-x)
+      (or cl-end (setq cl-end (length cl-seq)))
+      (if (consp cl-seq) (setq cl-seq (nthcdr cl-start cl-seq)))
+      (while (< cl-start cl-end)
+	(setq cl-x (if (consp cl-seq) (cl-pop cl-seq) (aref cl-seq cl-start)))
+	(if (cl-check-test cl-item cl-x) (setq cl-count (1+ cl-count)))
+	(setq cl-start (1+ cl-start)))
+      cl-count)))
+
+(defun count-if (cl-pred cl-list &rest cl-keys)
+  "Count the number of items satisfying PREDICATE in LIST.
+Keywords supported:  :key :start :end"
+  (apply 'count nil cl-list ':if cl-pred cl-keys))
+
+(defun count-if-not (cl-pred cl-list &rest cl-keys)
+  "Count the number of items not satisfying PREDICATE in LIST.
+Keywords supported:  :key :start :end"
+  (apply 'count nil cl-list ':if-not cl-pred cl-keys))
+
+(defun mismatch (cl-seq1 cl-seq2 &rest cl-keys)
+  "Compare SEQ1 with SEQ2, return index of first mismatching element.
+Return nil if the sequences match.  If one sequence is a prefix of the
+other, the return value indicates the end of the shorted sequence.
+Keywords supported:  :test :test-not :key :start1 :end1 :start2 :end2 :from-end"
+  (cl-parsing-keywords (:test :test-not :key :from-end
+			(:start1 0) :end1 (:start2 0) :end2) ()
+    (or cl-end1 (setq cl-end1 (length cl-seq1)))
+    (or cl-end2 (setq cl-end2 (length cl-seq2)))
+    (if cl-from-end
+	(progn
+	  (while (and (< cl-start1 cl-end1) (< cl-start2 cl-end2)
+		      (cl-check-match (elt cl-seq1 (1- cl-end1))
+				      (elt cl-seq2 (1- cl-end2))))
+	    (setq cl-end1 (1- cl-end1) cl-end2 (1- cl-end2)))
+	  (and (or (< cl-start1 cl-end1) (< cl-start2 cl-end2))
+	       (1- cl-end1)))
+      (let ((cl-p1 (and (listp cl-seq1) (nthcdr cl-start1 cl-seq1)))
+	    (cl-p2 (and (listp cl-seq2) (nthcdr cl-start2 cl-seq2))))
+	(while (and (< cl-start1 cl-end1) (< cl-start2 cl-end2)
+		    (cl-check-match (if cl-p1 (car cl-p1)
+				      (aref cl-seq1 cl-start1))
+				    (if cl-p2 (car cl-p2)
+				      (aref cl-seq2 cl-start2))))
+	  (setq cl-p1 (cdr cl-p1) cl-p2 (cdr cl-p2)
+		cl-start1 (1+ cl-start1) cl-start2 (1+ cl-start2)))
+	(and (or (< cl-start1 cl-end1) (< cl-start2 cl-end2))
+	     cl-start1)))))
+
+(defun search (cl-seq1 cl-seq2 &rest cl-keys)
+  "Search for SEQ1 as a subsequence of SEQ2.
+Return the index of the leftmost element of the first match found;
+return nil if there are no matches.
+Keywords supported:  :test :test-not :key :start1 :end1 :start2 :end2 :from-end"
+  (cl-parsing-keywords (:test :test-not :key :from-end
+			(:start1 0) :end1 (:start2 0) :end2) ()
+    (or cl-end1 (setq cl-end1 (length cl-seq1)))
+    (or cl-end2 (setq cl-end2 (length cl-seq2)))
+    (if (>= cl-start1 cl-end1)
+	(if cl-from-end cl-end2 cl-start2)
+      (let* ((cl-len (- cl-end1 cl-start1))
+	     (cl-first (cl-check-key (elt cl-seq1 cl-start1)))
+	     (cl-if nil) cl-pos)
+	(setq cl-end2 (- cl-end2 (1- cl-len)))
+	(while (and (< cl-start2 cl-end2)
+		    (setq cl-pos (cl-position cl-first cl-seq2
+					      cl-start2 cl-end2 cl-from-end))
+		    (apply 'mismatch cl-seq1 cl-seq2
+			   ':start1 (1+ cl-start1) ':end1 cl-end1
+			   ':start2 (1+ cl-pos) ':end2 (+ cl-pos cl-len)
+			   ':from-end nil cl-keys))
+	  (if cl-from-end (setq cl-end2 cl-pos) (setq cl-start2 (1+ cl-pos))))
+	(and (< cl-start2 cl-end2) cl-pos)))))
+
+(defun sort* (cl-seq cl-pred &rest cl-keys)
+  "Sort the argument SEQUENCE according to PREDICATE.
+This is a destructive function; it reuses the storage of SEQUENCE if possible.
+Keywords supported:  :key"
+  (if (nlistp cl-seq)
+      (replace cl-seq (apply 'sort* (append cl-seq nil) cl-pred cl-keys))
+    (cl-parsing-keywords (:key) ()
+      (if (memq cl-key '(nil identity))
+	  (sort cl-seq cl-pred)
+	(sort cl-seq (function (lambda (cl-x cl-y)
+				 (funcall cl-pred (funcall cl-key cl-x)
+					  (funcall cl-key cl-y)))))))))
+
+(defun stable-sort (cl-seq cl-pred &rest cl-keys)
+  "Sort the argument SEQUENCE stably according to PREDICATE.
+This is a destructive function; it reuses the storage of SEQUENCE if possible.
+Keywords supported:  :key"
+  (apply 'sort* cl-seq cl-pred cl-keys))
+
+(defun merge (cl-type cl-seq1 cl-seq2 cl-pred &rest cl-keys)
+  "Destructively merge the two sequences to produce a new sequence.
+TYPE is the sequence type to return, SEQ1 and SEQ2 are the two
+argument sequences, and PRED is a `less-than' predicate on the elements.
+Keywords supported:  :key"
+  (or (listp cl-seq1) (setq cl-seq1 (append cl-seq1 nil)))
+  (or (listp cl-seq2) (setq cl-seq2 (append cl-seq2 nil)))
+  (cl-parsing-keywords (:key) ()
+    (let ((cl-res nil))
+      (while (and cl-seq1 cl-seq2)
+	(if (funcall cl-pred (cl-check-key (car cl-seq2))
+		     (cl-check-key (car cl-seq1)))
+	    (cl-push (cl-pop cl-seq2) cl-res)
+	  (cl-push (cl-pop cl-seq1) cl-res)))
+      (coerce (nconc (nreverse cl-res) cl-seq1 cl-seq2) cl-type))))
+
+;;; See compiler macro in cl-macs.el
+(defun member* (cl-item cl-list &rest cl-keys)
+  "Find the first occurrence of ITEM in LIST.
+Return the sublist of LIST whose car is ITEM.
+Keywords supported:  :test :test-not :key"
+  (if cl-keys
+      (cl-parsing-keywords (:test :test-not :key :if :if-not) ()
+	(while (and cl-list (not (cl-check-test cl-item (car cl-list))))
+	  (setq cl-list (cdr cl-list)))
+	cl-list)
+    (if (and (numberp cl-item) (not (integerp cl-item)))
+	(member cl-item cl-list)
+      (memq cl-item cl-list))))
+
+(defun member-if (cl-pred cl-list &rest cl-keys)
+  "Find the first item satisfying PREDICATE in LIST.
+Return the sublist of LIST whose car matches.
+Keywords supported:  :key"
+  (apply 'member* nil cl-list ':if cl-pred cl-keys))
+
+(defun member-if-not (cl-pred cl-list &rest cl-keys)
+  "Find the first item not satisfying PREDICATE in LIST.
+Return the sublist of LIST whose car matches.
+Keywords supported:  :key"
+  (apply 'member* nil cl-list ':if-not cl-pred cl-keys))
+
+(defun cl-adjoin (cl-item cl-list &rest cl-keys)
+  (if (cl-parsing-keywords (:key) t
+	(apply 'member* (cl-check-key cl-item) cl-list cl-keys))
+      cl-list
+    (cons cl-item cl-list)))
+
+;;; See compiler macro in cl-macs.el
+(defun assoc* (cl-item cl-alist &rest cl-keys)
+  "Find the first item whose car matches ITEM in LIST.
+Keywords supported:  :test :test-not :key"
+  (if cl-keys
+      (cl-parsing-keywords (:test :test-not :key :if :if-not) ()
+	(while (and cl-alist
+		    (or (not (consp (car cl-alist)))
+			(not (cl-check-test cl-item (car (car cl-alist))))))
+	  (setq cl-alist (cdr cl-alist)))
+	(and cl-alist (car cl-alist)))
+    (if (and (numberp cl-item) (not (integerp cl-item)))
+	(assoc cl-item cl-alist)
+      (assq cl-item cl-alist))))
+
+(defun assoc-if (cl-pred cl-list &rest cl-keys)
+  "Find the first item whose car satisfies PREDICATE in LIST.
+Keywords supported:  :key"
+  (apply 'assoc* nil cl-list ':if cl-pred cl-keys))
+
+(defun assoc-if-not (cl-pred cl-list &rest cl-keys)
+  "Find the first item whose car does not satisfy PREDICATE in LIST.
+Keywords supported:  :key"
+  (apply 'assoc* nil cl-list ':if-not cl-pred cl-keys))
+
+(defun rassoc* (cl-item cl-alist &rest cl-keys)
+  "Find the first item whose cdr matches ITEM in LIST.
+Keywords supported:  :test :test-not :key"
+  (if (or cl-keys (numberp cl-item))
+      (cl-parsing-keywords (:test :test-not :key :if :if-not) ()
+	(while (and cl-alist
+		    (or (not (consp (car cl-alist)))
+			(not (cl-check-test cl-item (cdr (car cl-alist))))))
+	  (setq cl-alist (cdr cl-alist)))
+	(and cl-alist (car cl-alist)))
+    (rassq cl-item cl-alist)))
+
+(defun rassoc-if (cl-pred cl-list &rest cl-keys)
+  "Find the first item whose cdr satisfies PREDICATE in LIST.
+Keywords supported:  :key"
+  (apply 'rassoc* nil cl-list ':if cl-pred cl-keys))
+
+(defun rassoc-if-not (cl-pred cl-list &rest cl-keys)
+  "Find the first item whose cdr does not satisfy PREDICATE in LIST.
+Keywords supported:  :key"
+  (apply 'rassoc* nil cl-list ':if-not cl-pred cl-keys))
+
+(defun union (cl-list1 cl-list2 &rest cl-keys)
+  "Combine LIST1 and LIST2 using a set-union operation.
+The result list contains all items that appear in either LIST1 or LIST2.
+This is a non-destructive function; it makes a copy of the data if necessary
+to avoid corrupting the original LIST1 and LIST2.
+Keywords supported:  :test :test-not :key"
+  (cond ((null cl-list1) cl-list2) ((null cl-list2) cl-list1)
+	((equal cl-list1 cl-list2) cl-list1)
+	(t
+	 (or (>= (length cl-list1) (length cl-list2))
+	     (setq cl-list1 (prog1 cl-list2 (setq cl-list2 cl-list1))))
+	 (while cl-list2
+	   (if (or cl-keys (numberp (car cl-list2)))
+	       (setq cl-list1 (apply 'adjoin (car cl-list2) cl-list1 cl-keys))
+	     (or (memq (car cl-list2) cl-list1)
+		 (cl-push (car cl-list2) cl-list1)))
+	   (cl-pop cl-list2))
+	 cl-list1)))
+
+(defun nunion (cl-list1 cl-list2 &rest cl-keys)
+  "Combine LIST1 and LIST2 using a set-union operation.
+The result list contains all items that appear in either LIST1 or LIST2.
+This is a destructive function; it reuses the storage of LIST1 and LIST2
+whenever possible.
+Keywords supported:  :test :test-not :key"
+  (cond ((null cl-list1) cl-list2) ((null cl-list2) cl-list1)
+	(t (apply 'union cl-list1 cl-list2 cl-keys))))
+
+(defun intersection (cl-list1 cl-list2 &rest cl-keys)
+  "Combine LIST1 and LIST2 using a set-intersection operation.
+The result list contains all items that appear in both LIST1 and LIST2.
+This is a non-destructive function; it makes a copy of the data if necessary
+to avoid corrupting the original LIST1 and LIST2.
+Keywords supported:  :test :test-not :key"
+  (and cl-list1 cl-list2
+       (if (equal cl-list1 cl-list2) cl-list1
+	 (cl-parsing-keywords (:key) (:test :test-not)
+	   (let ((cl-res nil))
+	     (or (>= (length cl-list1) (length cl-list2))
+		 (setq cl-list1 (prog1 cl-list2 (setq cl-list2 cl-list1))))
+	     (while cl-list2
+	       (if (if (or cl-keys (numberp (car cl-list2)))
+		       (apply 'member* (cl-check-key (car cl-list2))
+			      cl-list1 cl-keys)
+		     (memq (car cl-list2) cl-list1))
+		   (cl-push (car cl-list2) cl-res))
+	       (cl-pop cl-list2))
+	     cl-res)))))
+
+(defun nintersection (cl-list1 cl-list2 &rest cl-keys)
+  "Combine LIST1 and LIST2 using a set-intersection operation.
+The result list contains all items that appear in both LIST1 and LIST2.
+This is a destructive function; it reuses the storage of LIST1 and LIST2
+whenever possible.
+Keywords supported:  :test :test-not :key"
+  (and cl-list1 cl-list2 (apply 'intersection cl-list1 cl-list2 cl-keys)))
+
+(defun set-difference (cl-list1 cl-list2 &rest cl-keys)
+  "Combine LIST1 and LIST2 using a set-difference operation.
+The result list contains all items that appear in LIST1 but not LIST2.
+This is a non-destructive function; it makes a copy of the data if necessary
+to avoid corrupting the original LIST1 and LIST2.
+Keywords supported:  :test :test-not :key"
+  (if (or (null cl-list1) (null cl-list2)) cl-list1
+    (cl-parsing-keywords (:key) (:test :test-not)
+      (let ((cl-res nil))
+	(while cl-list1
+	  (or (if (or cl-keys (numberp (car cl-list1)))
+		  (apply 'member* (cl-check-key (car cl-list1))
+			 cl-list2 cl-keys)
+		(memq (car cl-list1) cl-list2))
+	      (cl-push (car cl-list1) cl-res))
+	  (cl-pop cl-list1))
+	cl-res))))
+
+(defun nset-difference (cl-list1 cl-list2 &rest cl-keys)
+  "Combine LIST1 and LIST2 using a set-difference operation.
+The result list contains all items that appear in LIST1 but not LIST2.
+This is a destructive function; it reuses the storage of LIST1 and LIST2
+whenever possible.
+Keywords supported:  :test :test-not :key"
+  (if (or (null cl-list1) (null cl-list2)) cl-list1
+    (apply 'set-difference cl-list1 cl-list2 cl-keys)))
+
+(defun set-exclusive-or (cl-list1 cl-list2 &rest cl-keys)
+  "Combine LIST1 and LIST2 using a set-exclusive-or operation.
+The result list contains all items that appear in exactly one of LIST1, LIST2.
+This is a non-destructive function; it makes a copy of the data if necessary
+to avoid corrupting the original LIST1 and LIST2.
+Keywords supported:  :test :test-not :key"
+  (cond ((null cl-list1) cl-list2) ((null cl-list2) cl-list1)
+	((equal cl-list1 cl-list2) nil)
+	(t (append (apply 'set-difference cl-list1 cl-list2 cl-keys)
+		   (apply 'set-difference cl-list2 cl-list1 cl-keys)))))
+
+(defun nset-exclusive-or (cl-list1 cl-list2 &rest cl-keys)
+  "Combine LIST1 and LIST2 using a set-exclusive-or operation.
+The result list contains all items that appear in exactly one of LIST1, LIST2.
+This is a destructive function; it reuses the storage of LIST1 and LIST2
+whenever possible.
+Keywords supported:  :test :test-not :key"
+  (cond ((null cl-list1) cl-list2) ((null cl-list2) cl-list1)
+	((equal cl-list1 cl-list2) nil)
+	(t (nconc (apply 'nset-difference cl-list1 cl-list2 cl-keys)
+		  (apply 'nset-difference cl-list2 cl-list1 cl-keys)))))
+
+(defun subsetp (cl-list1 cl-list2 &rest cl-keys)
+  "True if LIST1 is a subset of LIST2.
+I.e., if every element of LIST1 also appears in LIST2.
+Keywords supported:  :test :test-not :key"
+  (cond ((null cl-list1) t) ((null cl-list2) nil)
+	((equal cl-list1 cl-list2) t)
+	(t (cl-parsing-keywords (:key) (:test :test-not)
+	     (while (and cl-list1
+			 (apply 'member* (cl-check-key (car cl-list1))
+				cl-list2 cl-keys))
+	       (cl-pop cl-list1))
+	     (null cl-list1)))))
+
+(defun subst-if (cl-new cl-pred cl-tree &rest cl-keys)
+  "Substitute NEW for elements matching PREDICATE in TREE (non-destructively).
+Return a copy of TREE with all matching elements replaced by NEW.
+Keywords supported:  :key"
+  (apply 'sublis (list (cons nil cl-new)) cl-tree ':if cl-pred cl-keys))
+
+(defun subst-if-not (cl-new cl-pred cl-tree &rest cl-keys)
+  "Substitute NEW for elts not matching PREDICATE in TREE (non-destructively).
+Return a copy of TREE with all non-matching elements replaced by NEW.
+Keywords supported:  :key"
+  (apply 'sublis (list (cons nil cl-new)) cl-tree ':if-not cl-pred cl-keys))
+
+(defun nsubst (cl-new cl-old cl-tree &rest cl-keys)
+  "Substitute NEW for OLD everywhere in TREE (destructively).
+Any element of TREE which is `eql' to OLD is changed to NEW (via a call
+to `setcar').
+Keywords supported:  :test :test-not :key"
+  (apply 'nsublis (list (cons cl-old cl-new)) cl-tree cl-keys))
+
+(defun nsubst-if (cl-new cl-pred cl-tree &rest cl-keys)
+  "Substitute NEW for elements matching PREDICATE in TREE (destructively).
+Any element of TREE which matches is changed to NEW (via a call to `setcar').
+Keywords supported:  :key"
+  (apply 'nsublis (list (cons nil cl-new)) cl-tree ':if cl-pred cl-keys))
+
+(defun nsubst-if-not (cl-new cl-pred cl-tree &rest cl-keys)
+  "Substitute NEW for elements not matching PREDICATE in TREE (destructively).
+Any element of TREE which matches is changed to NEW (via a call to `setcar').
+Keywords supported:  :key"
+  (apply 'nsublis (list (cons nil cl-new)) cl-tree ':if-not cl-pred cl-keys))
+
+(defun sublis (cl-alist cl-tree &rest cl-keys)
+  "Perform substitutions indicated by ALIST in TREE (non-destructively).
+Return a copy of TREE with all matching elements replaced.
+Keywords supported:  :test :test-not :key"
+  (cl-parsing-keywords (:test :test-not :key :if :if-not) ()
+    (cl-sublis-rec cl-tree)))
+
+(defvar cl-alist)
+(defun cl-sublis-rec (cl-tree)   ; uses cl-alist/key/test*/if*
+  (let ((cl-temp (cl-check-key cl-tree)) (cl-p cl-alist))
+    (while (and cl-p (not (cl-check-test-nokey (car (car cl-p)) cl-temp)))
+      (setq cl-p (cdr cl-p)))
+    (if cl-p (cdr (car cl-p))
+      (if (consp cl-tree)
+	  (let ((cl-a (cl-sublis-rec (car cl-tree)))
+		(cl-d (cl-sublis-rec (cdr cl-tree))))
+	    (if (and (eq cl-a (car cl-tree)) (eq cl-d (cdr cl-tree)))
+		cl-tree
+	      (cons cl-a cl-d)))
+	cl-tree))))
+
+(defun nsublis (cl-alist cl-tree &rest cl-keys)
+  "Perform substitutions indicated by ALIST in TREE (destructively).
+Any matching element of TREE is changed via a call to `setcar'.
+Keywords supported:  :test :test-not :key"
+  (cl-parsing-keywords (:test :test-not :key :if :if-not) ()
+    (let ((cl-hold (list cl-tree)))
+      (cl-nsublis-rec cl-hold)
+      (car cl-hold))))
+
+(defun cl-nsublis-rec (cl-tree)   ; uses cl-alist/temp/p/key/test*/if*
+  (while (consp cl-tree)
+    (let ((cl-temp (cl-check-key (car cl-tree))) (cl-p cl-alist))
+      (while (and cl-p (not (cl-check-test-nokey (car (car cl-p)) cl-temp)))
+	(setq cl-p (cdr cl-p)))
+      (if cl-p (setcar cl-tree (cdr (car cl-p)))
+	(if (consp (car cl-tree)) (cl-nsublis-rec (car cl-tree))))
+      (setq cl-temp (cl-check-key (cdr cl-tree)) cl-p cl-alist)
+      (while (and cl-p (not (cl-check-test-nokey (car (car cl-p)) cl-temp)))
+	(setq cl-p (cdr cl-p)))
+      (if cl-p
+	  (progn (setcdr cl-tree (cdr (car cl-p))) (setq cl-tree nil))
+	(setq cl-tree (cdr cl-tree))))))
+
+(defun tree-equal (cl-x cl-y &rest cl-keys)
+  "Return t if trees X and Y have `eql' leaves.
+Atoms are compared by `eql'; cons cells are compared recursively.
+Keywords supported:  :test :test-not :key"
+  (cl-parsing-keywords (:test :test-not :key) ()
+    (cl-tree-equal-rec cl-x cl-y)))
+
+(defun cl-tree-equal-rec (cl-x cl-y)
+  (while (and (consp cl-x) (consp cl-y)
+	      (cl-tree-equal-rec (car cl-x) (car cl-y)))
+    (setq cl-x (cdr cl-x) cl-y (cdr cl-y)))
+  (and (not (consp cl-x)) (not (consp cl-y)) (cl-check-match cl-x cl-y)))
+
+
+(run-hooks 'cl-seq-load-hook)
+
+;;; cl-seq.el ends here