Added full js & js_util packages

packages/quiver_iterables/lib/src/zip.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.iterables;
+
+/// Returns an [Iterable] of [List]s where the nth element in the returned
+/// iterable contains the nth element from every Iterable in [iterables]. The
+/// returned Iterable is as long as the shortest Iterable in the argument. If
+/// [iterables] is empty, it returns an empty list.
+Iterable<List> zip(Iterable<Iterable> iterables) sync* {
+  if (iterables.isEmpty) return;
+  var iterators = iterables.map((i) => i.iterator).toList(growable: false);
+  while (true) {
+    var zipped = new List(iterators.length);
+    for (var i = 0; i < zipped.length; i++) {
+      if (!iterators[i].moveNext()) return;
+      zipped[i] = iterators[i].current;
+    }
+    yield zipped;
+  }
+}