Implement a native identical function in the VM.

tests/language/identical_closure_test.dart

Index: tests/language/identical_closure_test.dart
diff --git a/tests/language/identical_closure_test.dart b/tests/language/identical_closure_test.dart
new file mode 100644
index 0000000000000000000000000000000000000000..34966388b4ea512928f7d34560a7a54d0c746b8e
--- /dev/null
+++ b/tests/language/identical_closure_test.dart
@@ -0,0 +1,24 @@
+// 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.
+
+var myIdentical = identical;
+
+class Point {
+  num x, y;
+  Point(this.x, this.y);
+}
+
+main() {
+  Expect.isTrue(myIdentical(42, 42));
+  Expect.isFalse(myIdentical(42, 41));
+  Expect.isFalse(myIdentical(42, 42.0));
+  Expect.isFalse(myIdentical("hello", 41));
+  var p = new Point(1,1);
+  var q = new Point(1,1);
+  Expect.isFalse(myIdentical(p, q));
+  var a = "hello";
+  var b = "hello";
+  // Identical strings are coalesced into single instances.
+  Expect.isTrue(myIdentical(a, b));

[srdjan, 2012/12/17 19:42:47]

Add tests for doubles, mints and bigints.

[Max Heinritz (Google), 2012/12/17 21:15:23]

Done.

+}