X-Git-Url: http://git.kpe.io/?p=kmrcl.git;a=blobdiff_plain;f=lists.lisp;h=c33d845148e801d06f68524b746513023b88ba72;hp=5cd193cefe96910174ef1c9a9a5039c0b1c9b7b5;hb=3ca593ad0ad02da7ebfd270523795674d6458ad3;hpb=7397fb7597f3fe9c658e6fb1ad67c805029dd073

diff --git a/lists.lisp b/lists.lisp
index 5cd193c..c33d845 100644
--- a/lists.lisp
+++ b/lists.lisp
@@ -7,8 +7,6 @@
 ;;;; Programmer:    Kevin M. Rosenberg
 ;;;; Date Started:  Apr 2000
 ;;;;
-;;;; $Id$
-;;;;
 ;;;; This file, part of KMRCL, is Copyright (c) 2002 by Kevin M. Rosenberg
 ;;;;
 ;;;; KMRCL users are granted the rights to distribute and use this software
@@ -73,11 +71,14 @@
             it
             nil)))))
 
-(defun flatten (lis)
-  (cond ((atom lis) lis)
-        ((listp (car lis))
-         (append (flatten (car lis)) (flatten (cdr lis))))
-        (t (append (list (car lis)) (flatten (cdr lis))))))
+(defun flatten (tree)
+  (let ((result '()))
+    (labels ((scan (item)
+               (if (consp item)
+                   (map nil #'scan item)
+                   (push item result))))
+      (scan tree))
+    (nreverse result)))
 
 ;;; Keyword functions
 
@@ -162,8 +163,8 @@
          (setf (cdr ,elem) ,val))
         (,alist
          (setf (cdr (last ,alist)) (list (cons ,akey ,val))))
-         (t
-          (setf ,alist (list (cons ,akey ,val)))))
+        (t
+         (setf ,alist (list (cons ,akey ,val)))))
        ,alist)))
 
 (defun get-alist (key alist &key (test #'eql))
@@ -174,6 +175,14 @@
   (update-alist key value alist :test test)
   value)
 
+(defun remove-alist (key alist &key (test #'eql))
+  "Removes a key from an alist."
+  (remove key alist :test test :key #'car))
+
+(defun delete-alist (key alist &key (test #'eql))
+  "Deletes a  key from an alist."
+  (delete key alist :test test :key #'car))
+
 (defun alist-plist (alist)
   (apply #'append (mapcar #'(lambda (x) (list (car x) (cdr x))) alist)))