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quiver/lib/src/collection/delegates/map.dart

-// Copyright 2013 Google Inc. All Rights Reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-part of quiver.collection;
-
-/**
- * An implementation of [Map] that delegates all methods to another [Map].
- * For instance you can create a FruitMap like this :
- *
- *     class FruitMap extends DelegatingMap<String, Fruit> {
- *       final Map<String, Fruit> _fruits = {};
- *
- *       Map<String, Fruit> get delegate => _fruits;
- *
- *       // custom methods
- *     }
- */
-abstract class DelegatingMap<K, V> implements Map<K, V> {
-  Map<K, V> get delegate;
-
-  V operator [](Object key) => delegate[key];
-
-  void operator []=(K key, V value) {
-    delegate[key] = value;
-  }
-
-  void addAll(Map<K, V> other) => delegate.addAll(other);
-
-  void clear() => delegate.clear();
-
-  bool containsKey(Object key) => delegate.containsKey(key);
-
-  bool containsValue(Object value) => delegate.containsValue(value);
-
-  void forEach(void f(K key, V value)) => delegate.forEach(f);
-
-  bool get isEmpty => delegate.isEmpty;
-
-  bool get isNotEmpty => delegate.isNotEmpty;
-
-  Iterable<K> get keys => delegate.keys;
-
-  int get length => delegate.length;
-
-  V putIfAbsent(K key, V ifAbsent()) => delegate.putIfAbsent(key, ifAbsent);
-
-  V remove(Object key) => delegate.remove(key);
-
-  Iterable<V> get values => delegate.values;
-}