diff --git a/sources/zweic/Parser.scala b/sources/zweic/Parser.scala
index 6b898bb..1c4a500 100755
--- a/sources/zweic/Parser.scala
+++ b/sources/zweic/Parser.scala
@@ -338,9 +338,9 @@
   * MyTerm = [ NegateOp ] Factor [ ProdOp Term ]
   */
   private def term(): Expr = {
-	var left:Expr;	
+	var left:Expr = null;	
 	if ( token == SUB || token == NOT ) {
-		val op = token;
+		val op = Operators.token2op(token);
 		nextToken;
 		val e = factor();
 		left = Unop(op, e);
@@ -355,9 +355,16 @@
 	return left;
   }
 
-  private def string(str: String): New = str match {
-  	case st::xs => return new New(Name("Cons"), IntLit(Int(st))::string(xs)::Nil)
-	case _ => return new New(Name("Nil"), Nil)
+
+  def string2List(s: String): List[Char] =
+      if (s.length() == 0)
+	Nil
+      else
+	s.charAt(0) :: string2List(s.substring(1));
+
+  private def _string(str: String): New = {
+    string2List(chars).toList.foldRight(New(Name("Nil"), Nil))((x, xs) => 
+      New(Name("Cons"), IntLit(x.asInstanceOf[Int])::List(xs)))
   }
 
   /**
@@ -369,7 +376,7 @@
 	token match {
 		case IDENT => nextToken; rval = Ident(Name(chars));
 		case NUMBER => nextToken; rval = IntLit(Integer.parseInt(chars));
-		case STRING => nextToken; rval = string(name);
+		case STRING => nextToken; rval = _string(name);
 		case TRUE => nextToken; rval = IntLit(1);
 		case FALSE => nextToken; rval = IntLit(0);
 		case THIS => nextToken; rval = Ident(Name("this"));