a === b -> identical(a, b)

tests/language/rethrow_test.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.
 // Dart test program for testing throw statement
 
 class MyException {
   const MyException();
 }
 
 class OtherException {
   const OtherException();
 }
 
 class RethrowTest {
   MyException currentException;
 
   void throwException() {
     currentException = new MyException();
     throw currentException;
   }
 
   void testRethrowPastUncaught() {
     try {
       try {
         try {
           throwException();
           Expect.fail("Should have thrown an exception");
         } catch (e) {
-          Expect.equals(true, e === currentException);
+          Expect.equals(true, identical(e, currentException));
           throw;
           Expect.fail("Should have thrown an exception");
         }
       } on OtherException catch (e) {
         Expect.fail("Should not have caught OtherException");
       }
     } catch (e) {
-      Expect.equals(true, e === currentException);
+      Expect.equals(true, identical(e, currentException));
     }
   }
 
   void testRethrow() {
     try {
       try {
         throwException();
         Expect.fail("Should have thrown an exception");
       } catch (e) {
-        Expect.equals(true, e === currentException);
+        Expect.equals(true, identical(e, currentException));
         throw;
         Expect.fail("Should have thrown an exception");
       }
     } catch (e) {
-      Expect.equals(true, e === currentException);
+      Expect.equals(true, identical(e, currentException));
     }
   }
 }
 
 main() {
   RethrowTest t = new RethrowTest();
   t.testRethrow();
   t.testRethrowPastUncaught();
 }