X-Git-Url: http://git.kpe.io/?p=kmrcl.git;a=blobdiff_plain;f=lists.lisp;h=dfa9d386d25d5c9f100c317372442b3ef15adcff;hp=229bc91d6cc40d73bece0377d419db1d56a83ee4;hb=ea921dd2ce51a46bb3ca92a07df095d5ace99dcf;hpb=ce1cbb4b287d275af616a81e30197b6e57a82d90

diff --git a/lists.lisp b/lists.lisp
index 229bc91..dfa9d38 100644
--- a/lists.lisp
+++ b/lists.lisp
@@ -151,18 +151,24 @@
 
 (defmacro update-alist (akey value alist &key (test '#'eql) (key '#'identity))
   "Macro to support below (setf get-alist)"
-  (let ((elem (gensym)))
-    `(let ((,elem (assoc ,akey ,alist :test ,test :key ,key)))
-       (if ,elem
-	   (progn
-	     (setf (cdr ,elem) ,value)
-	     ,alist)
-	(setf ,alist (acons ,akey ,value ,alist))))))
+  (let ((elem (gensym "ELEM-"))
+	(val (gensym "VAL-")))
+    `(let ((,elem (assoc ,akey ,alist :test ,test :key ,key))
+	   (,val ,value))
+       (cond
+	(,elem
+	 (setf (cdr ,elem) ,val))
+	(,alist
+	 (setf (cdr (last ,alist)) (list (cons ,akey ,val))))
+	 (t
+	  (setf ,alist (list (cons ,akey ,val)))))
+       ,alist)))
 
 (defun get-alist (key alist &key (test #'eql))
   (cdr (assoc key alist :test test)))
 
 (defun (setf get-alist) (value key alist &key (test #'eql))
+  "This won't work if the alist is NIL."
   (update-alist key value alist :test test)
   value)
 
@@ -186,3 +192,12 @@
 	 (setf ,plist (append ,plist (list ,pkey ,value)))))))
 
 
+(defun unique-slot-values (list slot &key (test 'eql))
+  (let ((uniq '()))
+    (dolist (item list (nreverse uniq))
+      (let ((value (slot-value item slot)))
+	(unless (find value uniq :test test)
+	  (push value uniq))))))
+
+
+