| // Copyright (c) 2013, 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. |
| |
| /** |
| * Delegating wrappers for [Iterable], [List], [Set], [Queue] and [Map]. |
| * |
| * Also adds unmodifiable views for `Set` and `Map`, and a fixed length |
| * view for `List`. The unmodifable list view from `dart:collection` is exported |
| * as well, just for completeness. |
| */ |
| library dart.pkg.collection.wrappers; |
| |
| import "dart:collection"; |
| import "dart:math" show Random; |
| |
| export "dart:collection" show UnmodifiableListView; |
| |
| export "src/canonicalized_map.dart"; |
| part "src/unmodifiable_wrappers.dart"; |
| |
| /** |
| * A base class for delegating iterables. |
| * |
| * Subclasses can provide a [_base] that should be delegated to. Unlike |
| * [DelegatingIterable], this allows the base to be created on demand. |
| */ |
| abstract class _DelegatingIterableBase<E> implements Iterable<E> { |
| Iterable<E> get _base; |
| |
| const _DelegatingIterableBase(); |
| |
| bool any(bool test(E element)) => _base.any(test); |
| |
| bool contains(Object element) => _base.contains(element); |
| |
| E elementAt(int index) => _base.elementAt(index); |
| |
| bool every(bool test(E element)) => _base.every(test); |
| |
| Iterable expand(Iterable f(E element)) => _base.expand(f); |
| |
| E get first => _base.first; |
| |
| E firstWhere(bool test(E element), {E orElse()}) => |
| _base.firstWhere(test, orElse: orElse); |
| |
| fold(initialValue, combine(previousValue, E element)) => |
| _base.fold(initialValue, combine); |
| |
| void forEach(void f(E element)) => _base.forEach(f); |
| |
| bool get isEmpty => _base.isEmpty; |
| |
| bool get isNotEmpty => _base.isNotEmpty; |
| |
| Iterator<E> get iterator => _base.iterator; |
| |
| String join([String separator = ""]) => _base.join(separator); |
| |
| E get last => _base.last; |
| |
| E lastWhere(bool test(E element), {E orElse()}) => |
| _base.lastWhere(test, orElse: orElse); |
| |
| int get length => _base.length; |
| |
| Iterable map(f(E element)) => _base.map(f); |
| |
| E reduce(E combine(E value, E element)) => _base.reduce(combine); |
| |
| E get single => _base.single; |
| |
| E singleWhere(bool test(E element)) => _base.singleWhere(test); |
| |
| Iterable<E> skip(int n) => _base.skip(n); |
| |
| Iterable<E> skipWhile(bool test(E value)) => _base.skipWhile(test); |
| |
| Iterable<E> take(int n) => _base.take(n); |
| |
| Iterable<E> takeWhile(bool test(E value)) => _base.takeWhile(test); |
| |
| List<E> toList({bool growable: true}) => _base.toList(growable: growable); |
| |
| Set<E> toSet() => _base.toSet(); |
| |
| Iterable<E> where(bool test(E element)) => _base.where(test); |
| |
| String toString() => _base.toString(); |
| } |
| |
| /** |
| * Creates an [Iterable] that delegates all operations to a base iterable. |
| * |
| * This class can be used hide non-`Iterable` methods of an iterable object, |
| * or it can be extended to add extra functionality on top of an existing |
| * iterable object. |
| */ |
| class DelegatingIterable<E> extends _DelegatingIterableBase<E> { |
| final Iterable<E> _base; |
| |
| /** |
| * Create a wrapper that forwards operations to [base]. |
| */ |
| const DelegatingIterable(Iterable<E> base) : _base = base; |
| } |
| |
| |
| /** |
| * Creates a [List] that delegates all operations to a base list. |
| * |
| * This class can be used hide non-`List` methods of a list object, |
| * or it can be extended to add extra functionality on top of an existing |
| * list object. |
| */ |
| class DelegatingList<E> extends DelegatingIterable<E> implements List<E> { |
| const DelegatingList(List<E> base) : super(base); |
| |
| List<E> get _listBase => _base; |
| |
| E operator [](int index) => _listBase[index]; |
| |
| void operator []=(int index, E value) { |
| _listBase[index] = value; |
| } |
| |
| void add(E value) { |
| _listBase.add(value); |
| } |
| |
| void addAll(Iterable<E> iterable) { |
| _listBase.addAll(iterable); |
| } |
| |
| Map<int, E> asMap() => _listBase.asMap(); |
| |
| void clear() { |
| _listBase.clear(); |
| } |
| |
| void fillRange(int start, int end, [E fillValue]) { |
| _listBase.fillRange(start, end, fillValue); |
| } |
| |
| Iterable<E> getRange(int start, int end) => _listBase.getRange(start, end); |
| |
| int indexOf(E element, [int start = 0]) => _listBase.indexOf(element, start); |
| |
| void insert(int index, E element) { |
| _listBase.insert(index, element); |
| } |
| |
| void insertAll(int index, Iterable<E> iterable) { |
| _listBase.insertAll(index, iterable); |
| } |
| |
| int lastIndexOf(E element, [int start]) => |
| _listBase.lastIndexOf(element, start); |
| |
| void set length(int newLength) { |
| _listBase.length = newLength; |
| } |
| |
| bool remove(Object value) => _listBase.remove(value); |
| |
| E removeAt(int index) => _listBase.removeAt(index); |
| |
| E removeLast() => _listBase.removeLast(); |
| |
| void removeRange(int start, int end) { |
| _listBase.removeRange(start, end); |
| } |
| |
| void removeWhere(bool test(E element)) { |
| _listBase.removeWhere(test); |
| } |
| |
| void replaceRange(int start, int end, Iterable<E> iterable) { |
| _listBase.replaceRange(start, end, iterable); |
| } |
| |
| void retainWhere(bool test(E element)) { |
| _listBase.retainWhere(test); |
| } |
| |
| Iterable<E> get reversed => _listBase.reversed; |
| |
| void setAll(int index, Iterable<E> iterable) { |
| _listBase.setAll(index, iterable); |
| } |
| |
| void setRange(int start, int end, Iterable<E> iterable, [int skipCount = 0]) { |
| _listBase.setRange(start, end, iterable, skipCount); |
| } |
| |
| void shuffle([Random random]) { |
| _listBase.shuffle(random); |
| } |
| |
| void sort([int compare(E a, E b)]) { |
| _listBase.sort(compare); |
| } |
| |
| List<E> sublist(int start, [int end]) => _listBase.sublist(start, end); |
| } |
| |
| |
| /** |
| * Creates a [Set] that delegates all operations to a base set. |
| * |
| * This class can be used hide non-`Set` methods of a set object, |
| * or it can be extended to add extra functionality on top of an existing |
| * set object. |
| */ |
| class DelegatingSet<E> extends DelegatingIterable<E> implements Set<E> { |
| const DelegatingSet(Set<E> base) : super(base); |
| |
| Set<E> get _setBase => _base; |
| |
| bool add(E value) => _setBase.add(value); |
| |
| void addAll(Iterable<E> elements) { |
| _setBase.addAll(elements); |
| } |
| |
| void clear() { |
| _setBase.clear(); |
| } |
| |
| bool containsAll(Iterable<Object> other) => _setBase.containsAll(other); |
| |
| Set<E> difference(Set<E> other) => _setBase.difference(other); |
| |
| Set<E> intersection(Set<Object> other) => _setBase.intersection(other); |
| |
| E lookup(E element) => _setBase.lookup(element); |
| |
| bool remove(Object value) => _setBase.remove(value); |
| |
| void removeAll(Iterable<Object> elements) { |
| _setBase.removeAll(elements); |
| } |
| |
| void removeWhere(bool test(E element)) { |
| _setBase.removeWhere(test); |
| } |
| |
| void retainAll(Iterable<Object> elements) { |
| _setBase.retainAll(elements); |
| } |
| |
| void retainWhere(bool test(E element)) { |
| _setBase.retainWhere(test); |
| } |
| |
| Set<E> union(Set<E> other) => _setBase.union(other); |
| |
| Set<E> toSet() => new DelegatingSet<E>(_setBase.toSet()); |
| } |
| |
| /** |
| * Creates a [Queue] that delegates all operations to a base queue. |
| * |
| * This class can be used hide non-`Queue` methods of a queue object, |
| * or it can be extended to add extra functionality on top of an existing |
| * queue object. |
| */ |
| class DelegatingQueue<E> extends DelegatingIterable<E> implements Queue<E> { |
| const DelegatingQueue(Queue<E> queue) : super(queue); |
| |
| Queue<E> get _baseQueue => _base; |
| |
| void add(E value) { |
| _baseQueue.add(value); |
| } |
| |
| void addAll(Iterable<E> iterable) { |
| _baseQueue.addAll(iterable); |
| } |
| |
| void addFirst(E value) { |
| _baseQueue.addFirst(value); |
| } |
| |
| void addLast(E value) { |
| _baseQueue.addLast(value); |
| } |
| |
| void clear() { |
| _baseQueue.clear(); |
| } |
| |
| bool remove(Object object) => _baseQueue.remove(object); |
| |
| void removeWhere(bool test(E element)) { _baseQueue.removeWhere(test); } |
| |
| void retainWhere(bool test(E element)) { _baseQueue.retainWhere(test); } |
| |
| E removeFirst() => _baseQueue.removeFirst(); |
| |
| E removeLast() => _baseQueue.removeLast(); |
| } |
| |
| /** |
| * Creates a [Map] that delegates all operations to a base map. |
| * |
| * This class can be used hide non-`Map` methods of an object that extends |
| * `Map`, or it can be extended to add extra functionality on top of an existing |
| * map object. |
| */ |
| class DelegatingMap<K, V> implements Map<K, V> { |
| final Map<K, V> _base; |
| |
| const DelegatingMap(Map<K, V> base) : _base = base; |
| |
| V operator [](Object key) => _base[key]; |
| |
| void operator []=(K key, V value) { |
| _base[key] = value; |
| } |
| |
| void addAll(Map<K, V> other) { |
| _base.addAll(other); |
| } |
| |
| void clear() { |
| _base.clear(); |
| } |
| |
| bool containsKey(Object key) => _base.containsKey(key); |
| |
| bool containsValue(Object value) => _base.containsValue(value); |
| |
| void forEach(void f(K key, V value)) { |
| _base.forEach(f); |
| } |
| |
| bool get isEmpty => _base.isEmpty; |
| |
| bool get isNotEmpty => _base.isNotEmpty; |
| |
| Iterable<K> get keys => _base.keys; |
| |
| int get length => _base.length; |
| |
| V putIfAbsent(K key, V ifAbsent()) => _base.putIfAbsent(key, ifAbsent); |
| |
| V remove(Object key) => _base.remove(key); |
| |
| Iterable<V> get values => _base.values; |
| |
| String toString() => _base.toString(); |
| } |
| |
| /** |
| * An unmodifiable [Set] view of the keys of a [Map]. |
| * |
| * The set delegates all operations to the underlying map. |
| * |
| * A `Map` can only contain each key once, so its keys can always |
| * be viewed as a `Set` without any loss, even if the [Map.keys] |
| * getter only shows an [Iterable] view of the keys. |
| * |
| * Note that [lookup] is not supported for this set. |
| */ |
| class MapKeySet<E> extends _DelegatingIterableBase<E> |
| with UnmodifiableSetMixin<E> { |
| final Map<E, dynamic> _baseMap; |
| |
| MapKeySet(Map<E, dynamic> base) : _baseMap = base; |
| |
| Iterable<E> get _base => _baseMap.keys; |
| |
| bool contains(Object element) => _baseMap.containsKey(element); |
| |
| bool get isEmpty => _baseMap.isEmpty; |
| |
| bool get isNotEmpty => _baseMap.isNotEmpty; |
| |
| int get length => _baseMap.length; |
| |
| String toString() => "{${_base.join(', ')}}"; |
| |
| bool containsAll(Iterable<Object> other) => other.every(contains); |
| |
| /** |
| * Returns a new set with the the elements of [this] that are not in [other]. |
| * |
| * That is, the returned set contains all the elements of this [Set] that are |
| * not elements of [other] according to `other.contains`. |
| * |
| * Note that the returned set will use the default equality operation, which |
| * may be different than the equality operation [this] uses. |
| */ |
| Set<E> difference(Set<E> other) => |
| where((element) => !other.contains(element)).toSet(); |
| |
| /** |
| * Returns a new set which is the intersection between [this] and [other]. |
| * |
| * That is, the returned set contains all the elements of this [Set] that are |
| * also elements of [other] according to `other.contains`. |
| * |
| * Note that the returned set will use the default equality operation, which |
| * may be different than the equality operation [this] uses. |
| */ |
| Set<E> intersection(Set<Object> other) => where(other.contains).toSet(); |
| |
| /** |
| * Throws an [UnsupportedError] since there's no corresponding method for |
| * [Map]s. |
| */ |
| E lookup(E element) => throw new UnsupportedError( |
| "MapKeySet doesn't support lookup()."); |
| |
| /** |
| * Returns a new set which contains all the elements of [this] and [other]. |
| * |
| * That is, the returned set contains all the elements of this [Set] and all |
| * the elements of [other]. |
| * |
| * Note that the returned set will use the default equality operation, which |
| * may be different than the equality operation [this] uses. |
| */ |
| Set<E> union(Set<E> other) => toSet()..addAll(other); |
| } |
| |
| /** |
| * Creates a modifiable [Set] view of the values of a [Map]. |
| * |
| * The `Set` view assumes that the keys of the `Map` can be uniquely determined |
| * from the values. The `keyForValue` function passed to the constructor finds |
| * the key for a single value. The `keyForValue` function should be consistent |
| * with equality. If `value1 == value2` then `keyForValue(value1)` and |
| * `keyForValue(value2)` should be considered equal keys by the underlying map, |
| * and vice versa. |
| * |
| * Modifying the set will modify the underlying map based on the key returned by |
| * `keyForValue`. |
| * |
| * If the `Map` contents are not compatible with the `keyForValue` function, the |
| * set will not work consistently, and may give meaningless responses or do |
| * inconsistent updates. |
| * |
| * This set can, for example, be used on a map from database record IDs to the |
| * records. It exposes the records as a set, and allows for writing both |
| * `recordSet.add(databaseRecord)` and `recordMap[id]`. |
| * |
| * Effectively, the map will act as a kind of index for the set. |
| */ |
| class MapValueSet<K, V> extends _DelegatingIterableBase<V> implements Set<V> { |
| final Map<K, V> _baseMap; |
| final Function _keyForValue; |
| |
| /** |
| * Creates a new [MapValueSet] based on [base]. |
| * |
| * [keyForValue] returns the key in the map that should be associated with the |
| * given value. The set's notion of equality is identical to the equality of |
| * the return values of [keyForValue]. |
| */ |
| MapValueSet(Map<K, V> base, K keyForValue(V value)) |
| : _baseMap = base, |
| _keyForValue = keyForValue; |
| |
| Iterable<V> get _base => _baseMap.values; |
| |
| bool contains(Object element) { |
| if (element != null && element is! V) return false; |
| return _baseMap.containsKey(_keyForValue(element)); |
| } |
| |
| bool get isEmpty => _baseMap.isEmpty; |
| |
| bool get isNotEmpty => _baseMap.isNotEmpty; |
| |
| int get length => _baseMap.length; |
| |
| String toString() => toSet().toString(); |
| |
| bool add(V value) { |
| K key = _keyForValue(value); |
| bool result = false; |
| _baseMap.putIfAbsent(key, () { |
| result = true; |
| return value; |
| }); |
| return result; |
| } |
| |
| void addAll(Iterable<V> elements) => elements.forEach(add); |
| |
| void clear() => _baseMap.clear(); |
| |
| bool containsAll(Iterable<Object> other) => other.every(contains); |
| |
| /** |
| * Returns a new set with the the elements of [this] that are not in [other]. |
| * |
| * That is, the returned set contains all the elements of this [Set] that are |
| * not elements of [other] according to `other.contains`. |
| * |
| * Note that the returned set will use the default equality operation, which |
| * may be different than the equality operation [this] uses. |
| */ |
| Set<V> difference(Set<V> other) => |
| where((element) => !other.contains(element)).toSet(); |
| |
| /** |
| * Returns a new set which is the intersection between [this] and [other]. |
| * |
| * That is, the returned set contains all the elements of this [Set] that are |
| * also elements of [other] according to `other.contains`. |
| * |
| * Note that the returned set will use the default equality operation, which |
| * may be different than the equality operation [this] uses. |
| */ |
| Set<V> intersection(Set<Object> other) => where(other.contains).toSet(); |
| |
| V lookup(V element) => _baseMap[_keyForValue(element)]; |
| |
| bool remove(Object value) { |
| if (value != null && value is! V) return false; |
| var key = _keyForValue(value); |
| if (!_baseMap.containsKey(key)) return false; |
| _baseMap.remove(key); |
| return true; |
| } |
| |
| void removeAll(Iterable<Object> elements) => elements.forEach(remove); |
| |
| void removeWhere(bool test(V element)) { |
| var toRemove = []; |
| _baseMap.forEach((key, value) { |
| if (test(value)) toRemove.add(key); |
| }); |
| toRemove.forEach(_baseMap.remove); |
| } |
| |
| void retainAll(Iterable<Object> elements) { |
| var valuesToRetain = new Set<V>.identity(); |
| for (var element in elements) { |
| if (element != null && element is! V) continue; |
| var key = _keyForValue(element); |
| if (!_baseMap.containsKey(key)) continue; |
| valuesToRetain.add(_baseMap[key]); |
| } |
| |
| var keysToRemove = []; |
| _baseMap.forEach((k, v) { |
| if (!valuesToRetain.contains(v)) keysToRemove.add(k); |
| }); |
| keysToRemove.forEach(_baseMap.remove); |
| } |
| |
| void retainWhere(bool test(V element)) => |
| removeWhere((element) => !test(element)); |
| |
| /** |
| * Returns a new set which contains all the elements of [this] and [other]. |
| * |
| * That is, the returned set contains all the elements of this [Set] and all |
| * the elements of [other]. |
| * |
| * Note that the returned set will use the default equality operation, which |
| * may be different than the equality operation [this] uses. |
| */ |
| Set<V> union(Set<V> other) => toSet()..addAll(other); |
| } |