Add fromIterable(s) constructors in SplayTreeMap and LinkedHashMap.

sdk/lib/collection/splay_tree.dart

 // 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.
 
 part of dart.collection;
 
 /**
  * A node in a splay tree. It holds the sorting key and the left
  * and right children in the tree.
  */
@@ skipping 230 matching lines @@
  * method. This also means that `null` is *not* allowed as a key.
  */
 class SplayTreeMap<K, V> extends _SplayTree<K> implements Map<K, V> {
   // TODO(ngeoffray): Restore type when feature is implemented in dart2js
   // checked mode. http://dartbug.com/7733
   Function /* Comparator<K> */_comparator;
 
   SplayTreeMap([int compare(K key1, K key2)])
       : _comparator = (compare == null) ? Comparable.compare : compare;
 
+  /**
+   * Creates a [SplayTreeMap] that contains all key value pairs of [other].
+   */
   factory SplayTreeMap.from(Map<K, V> other, [int compare(K key1, K key2)]) =>
       new SplayTreeMap(compare)..addAll(other);
 
+  /**
+   * Creates a [SplayTreeMap] where the keys and values are computed from the
+   * [iterable].
+   *
+   * For each element of the [iterable] this constructor computes a key/value
+   * pair, by applying [key] and [value] respectively.
+   *
+   * The keys of the key/value pairs do not need to be unique. The last
+   * occurrence of a key will simply overwrite any previous value.
+   *
+   * If no values are specified for [key] and [value] the default is the
+   * identity function.
+   */
+  factory SplayTreeMap.fromIterable(Iterable<K> iterable,
+      {K key(element), V value(element), int compare(K key1, K key2)}) {
+    SplayTreeMap<K, V> map = new SplayTreeMap<K, V>(compare);
+    Maps._fillMapWithMappedIterable(map, iterable, key, value);
+    return map;
+  }
+
+  /**
+   * Creates a [SplayTreeMap] associating the given [keys] to [values].
+   *
+   * This constructor iterates over [keys] and [values] and maps each element of
+   * [keys] to the corresponding element of [values].
+   *
+   * If [keys] contains the same object multiple times, the last occurrence
+   * overwrites the previous value.
+   *
+   * It is an error if the two [Iterable]s don't have the same length.
+   */
+  factory SplayTreeMap.fromIterables(Iterable<K> keys, Iterable<V> values,
+      [int compare(K key1, K key2)]) {
+    SplayTreeMap<K, V> map = new SplayTreeMap<K, V>(compare);
+    Maps._fillMapWithIterables(map, keys, values);
+    return map;
+  }
+
   int _compare(K key1, K key2) => _comparator(key1, key2);
 
   SplayTreeMap._internal();
 
   V operator [](Object key) {
     if (key == null) throw new ArgumentError(key);
     if (key is! K) return null;
     if (_root != null) {
       int comp = _splay(key);
       if (comp == 0) {
@@ skipping 273 matching lines @@
 class _SplayTreeValueIterator<K, V> extends _SplayTreeIterator<V> {
   _SplayTreeValueIterator(SplayTreeMap<K, V> map): super(map);
   V _getValue(_SplayTreeMapNode node) => node.value;
 }
 
 class _SplayTreeNodeIterator<K>
     extends _SplayTreeIterator<_SplayTreeNode<K>> {
   _SplayTreeNodeIterator(_SplayTree<K> map): super(map);
   _SplayTreeNode<K> _getValue(_SplayTreeNode node) => node;
 }