| // Copyright (c) 2016, 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. |
| |
| library observable.src.to_observable; |
| |
| import 'dart:collection'; |
| |
| import 'observable.dart' show Observable; |
| import 'collections.dart' show ObservableList, ObservableMap; |
| |
| /// Converts the [Iterable] or [Map] to an [ObservableList] or [ObservableMap], |
| /// respectively. This is a convenience function to make it easier to convert |
| /// literals into the corresponding observable collection type. |
| /// |
| /// If [value] is not one of those collection types, or is already [Observable], |
| /// it will be returned unmodified. |
| /// |
| /// If [value] is a [Map], the resulting value will use the appropriate kind of |
| /// backing map: either [HashMap], [LinkedHashMap], or [SplayTreeMap]. |
| /// |
| /// By default this performs a deep conversion, but you can set [deep] to false |
| /// for a shallow conversion. This does not handle circular data structures. |
| /// If a conversion is peformed, mutations are only observed to the result of |
| /// this function. Changing the original collection will not affect it. |
| // TODO(jmesserly): ObservableSet? |
| toObservable(dynamic value, {bool deep: true}) => |
| deep ? _toObservableDeep(value) : _toObservableShallow(value); |
| |
| dynamic _toObservableShallow(dynamic value) { |
| if (value is Observable) return value; |
| if (value is Map) return new ObservableMap.from(value); |
| if (value is Iterable) return new ObservableList.from(value); |
| return value; |
| } |
| |
| dynamic _toObservableDeep(dynamic value) { |
| if (value is Observable) return value; |
| if (value is Map) { |
| var result = new ObservableMap.createFromType(value); |
| value.forEach((k, v) { |
| result[_toObservableDeep(k)] = _toObservableDeep(v); |
| }); |
| return result; |
| } |
| if (value is Iterable) { |
| return new ObservableList.from(value.map(_toObservableDeep)); |
| } |
| return value; |
| } |