Native implementation of List,setRange for frog.

frog/lib/corelib_impl.dart

Index: frog/lib/corelib_impl.dart
===================================================================
--- frog/lib/corelib_impl.dart	(revision 2921)
+++ frog/lib/corelib_impl.dart	(working copy)
@@ -72,7 +72,28 @@
   List<E> getRange(int start, int length) native
     "return this.slice(start, start + length);";
 
-  void setRange(int start, int length, List<E> from, [int startFrom]) native;
+  void setRange(int start, int length, List<E> from, [int startFrom]) {
+    // length of 0 prevails and should not throw exceptions.
+    if (length == 0)

[Jennifer Messerly, 2012/01/05 17:59:33]

style nit: we generally put these on one line, or else add { }

[dominich, 2012/01/05 18:19:57]

Done.

+      return;
+
+    if (length < 0)
+      throw new IllegalArgumentException('length is negative in setRange');
+
+    if (start < 0)
+      throw new IndexOutOfRangeException(start);
+    if (start + length > this.length)
+      throw new IndexOutOfRangeException(start + length);
+    startFrom = (startFrom == null ? 0 : startFrom);
+    if (startFrom < 0)
+      throw new IndexOutOfRangeException(startFrom);
+    if (startFrom + length > from.length)
+      throw new IndexOutOfRangeException(startFrom + length);
+
+    for (var i = 0; i < length; ++i)
+      this[start + i] = from[startFrom + i];
+  }
+
   void removeRange(int start, int length) native "this.splice(start, length);";
 
   void insertRange(int start, int length, [E initialValue]) native