Make String.fromCharCodes take start/end.

sdk/lib/internal/iterable.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.
 
 part of dart._internal;
 
 /**
  * Marker interface for [Iterable] subclasses that have an efficient
  * [length] implementation.
  */
@@ skipping 208 matching lines @@
   Set<E> toSet() {
     Set<E> result = new Set<E>();
     for (int i = 0; i < length; i++) {
       result.add(elementAt(i));
     }
     return result;
   }
 }
 
 class SubListIterable<E> extends ListIterable<E> {
-  final Iterable<E> _iterable;
+  final Iterable<E> _iterable;  // Has efficient length and elementAt.
   final int _start;
   /** If null, represents the length of the iterable. */
   final int _endOrLength;
 
   SubListIterable(this._iterable, this._start, this._endOrLength) {
     if (_start < 0) {
       throw new RangeError.value(_start);
     }
     if (_endOrLength != null) {
       if (_endOrLength < 0) {
@@ skipping 46 matching lines @@
   Iterable<E> take(int count) {
     if (count < 0) throw new RangeError.value(count);
     if (_endOrLength == null) {
       return new SubListIterable<E>(_iterable, _start, _start + count);
     } else {
       int newEnd = _start + count;
       if (_endOrLength < newEnd) return this;
       return new SubListIterable<E>(_iterable, _start, newEnd);
     }
   }
+
+  List<E> toList({bool growable: false}) {
+    int start = _start;
+    int end = _iterable.length;
+    if (_endOrLength != null && _endOrLength < end) end = _endOrLength;
+    int length = end - start;
+    if (length < 0) length = 0;
+    List result = growable ? (new List<E>()..length = length)
+                           : new List<E>(length);
+    for (int i = 0; i < length; i++) {
+      result[i] = _iterable.elementAt(start + i);
+      if (_iterable.length < end) throw new ConcurrentModificationError(this);
+    }
+    return result;
+  }
 }
 
 /**
  * An [Iterator] that iterates a list-like [Iterable].
  *
  * All iterations is done in terms of [Iterable.length] and
  * [Iterable.elementAt]. These operations are fast for list-like
  * iterables.
  */
 class ListIterator<E> implements Iterator<E> {
@@ skipping 844 matching lines @@
  * Creates errors throw by [Iterable] when the element count is wrong.
  */
 abstract class IterableElementError {
   /** Error thrown thrown by, e.g., [Iterable.first] when there is no result. */
   static StateError noElement() => new StateError("No element");
   /** Error thrown by, e.g., [Iterable.single] if there are too many results. */
   static StateError tooMany() => new StateError("Too many elements");
   /** Error thrown by, e.g., [List.setRange] if there are too few elements. */
   static StateError tooFew() => new StateError("Too few elements");
 }