Implement List.getRange.

runtime/lib/array.dart

 // Copyright (c) 2011, 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.
 
 class ArrayFactory<T> {
   factory Array.from(Iterable<T> other) {
     GrowableObjectArray<T> array = new GrowableObjectArray<T>();
     for (final e in other) {
       array.add(e);
     }
@@ skipping 89 matching lines @@
   void removeRange(int start, int length) {
     throw const UnsupportedOperationException(
         "Cannot remove range of a non-extendable array");
   }
 
   void insertRange(int start, int length, [T initialValue = null]) {
     throw const NotImplementedException();
   }
 
   List<T> getRange(int start, int length) {
-    throw const NotImplementedException();
+    if (length == 0) return [];
+    Arrays.rangeCheck(this, start, length);
+    return new List<T>.fromList(this, start, start + length);
   }
 
   /**
    * Collection interface.
    */
 
   void forEach(f(T element)) {
     Collections.forEach(this, f);
   }
 
@@ skipping 95 matching lines @@
   void removeRange(int start, int length) {
     throw const UnsupportedOperationException(
         "Cannot remove range of an immutable array");
   }
 
   void insertRange(int start, int length, [T initialValue = null]) {
     throw const NotImplementedException();
   }
 
   List<T> getRange(int start, int length) {
-    throw const NotImplementedException();
+    if (length == 0) return [];
+    Arrays.rangeCheck(this, start, length);
+    return new List<T>.fromList(this, start, start + length);
   }
 
   /**
    * Collection interface.
    */
 
   void forEach(f(T element)) {
     Collections.forEach(this, f);
   }
 
@@ skipping 84 matching lines @@
     if (!hasNext()) {
       throw const NoMoreElementsException();
     }
     return _array[_pos++];
   }
 
   final Array<T> _array;
   final int _length;  // Cache array length for faster access.
   int _pos;
 }