20110406-2237

1 files changed, 8 insertions, 5 deletions

diff --git a/appl/lib/lists.b b/appl/lib/lists.b
index 2210c33e..52e007bb 100644
--- a/appl/lib/lists.b
+++ b/appl/lib/lists.b
@@ -88,18 +88,21 @@ last[T](l: list of T): T
 }
 
 # delete the first instance of x in l
-delete[T](x: T, l: list of T): list of T
+delete[T](x: T, al: list of T): list of T
 	for { T =>	eq:	fn(a, b: T): int; }
 {
-	o: list of T;
-	for(; l != nil; l = tl l)
+	for(l := al; l != nil; l = tl l){
 		if(T.eq(x, hd l)){
+			o: list of T;
+			for(; al != l; al = tl al)
+				o = hd al :: o;
 			l = tl l;
 			for(; o != nil; o = tl o)
 				l = hd o :: l;
-			break;
+			return l;
 		}
-	return l;
+	}
+	return al;
 }
 
 pair[T1, T2](l1: list of T1, l2: list of T2): list of (T1, T2)