blob: c6c61ab4aff6de5e51e72e44bc21b46c35f92b45 [file] [log] [blame]
// Copyright (c) 2012, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
// VMOptions=--enable_checked_mode
import "dart:collection";
abstract class Link<T> extends IterableBase<T> {
factory Link(T head, [Link<T> tail]) = LinkEntry<T>;
Link<T> prepend(T element);
abstract class EmptyLink<T> extends Link<T> {
const factory EmptyLink() = LinkTail<T>;
class AbstractLink<T> implements Link<T> {
const AbstractLink();
Link<T> prepend(T element) {
if (0 is T) {
throw "0 is not a T";
return new Link<T>(element, this);
class LinkTail<T> extends AbstractLink<T> implements EmptyLink<T> {
const LinkTail();
class LinkEntry<T> extends AbstractLink<T> {
LinkEntry(T head, [Link<T> Tail]);
class Fisk {
Link<Fisk> nodes = const EmptyLink<Fisk>();
final int id;
toString() => id.toString();
main() {
new Fisk(0).nodes.prepend(new Fisk(1)).prepend(new Fisk(2));