Fix position rule

libwccl/parser/grammar.g

@@ -272,8 +272,11 @@ boolean_value
 // returns boost::shared_ptr<Wccl::Position>
 position_literal
 	returns [boost::shared_ptr<Wccl::Position> val]
-	: i: UNSIGNED_INT {
-		val.reset(new Wccl::Position(Wccl::Position(token_ref_to_int(i))));
+{
+	int i = 0;
+}
+	: i = number {
+		val.reset(new Wccl::Position(Wccl::Position(i)));
 	}
 	| "begin" {
 		val.reset(new Wccl::Position(Wccl::Position(Wccl::Position::Begin)));