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

tests/compiler/dart2js_extra/bailout_on_continue_test.dart

 // 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.
 
 class A {
   operator+(arg) => 42;
 }
 
 get42() => 42;
 getNonInt() => new A();
 use(x) => x;
 
 void testInWhileLoop() {
   var c = get42();
   int index = 0;
   while (index++ != 2) {
     var e = getNonInt();
     Expect.equals(42, e + 2);
-    if (e !== null) continue;
+    if (e != null) continue;
     while (true) use(e);
   }
   // 'c' must have been saved in the environment.
   Expect.equals(c, 42);
 }
 
 void testInNestedWhileLoop() {
   var c = get42();
   int index = 0;
   while (true) {
     while (index++ != 2) {
       var e = getNonInt();
       Expect.equals(42, e + 2);
-      if (e !== null) continue;
+      if (e != null) continue;
     }
     // 'c' must have been saved in the environment.
     Expect.equals(c, 42);
     if (c == 42) break;
   }
 }
 
 void testInNestedWhileLoop2() {
   var c = get42();
   int index = 0;
   L0: while (index++ != 2) {
     while (true) {
       var e = getNonInt();
       Expect.equals(42, e + 2);
-      if (e !== null) continue L0;
+      if (e != null) continue L0;
       while (true) use(e);
     }
   }
   // 'c' must have been saved in the environment.
   Expect.equals(c, 42);
 }
 
 void testInNestedWhileLoop3() {
   var c = get42();
   int index = 0;
   while (index < 2) {
     while (index < 2) {
       var e = getNonInt();
       Expect.equals(42, e + 2);
-      if (e !== null && index++ == 0) continue;
+      if (e != null && index++ == 0) continue;
       // 'c' must have been saved in the environment.
       Expect.equals(c, 42);
-      while (e === null) use(e);
+      while (e == null) use(e);
     }
   }
 }
 
 void testInDoWhileLoop() {
   var c = get42();
   int index = 0;
   do {
     var e = getNonInt();
     Expect.equals(42, e + 2);
-    if (e !== null) continue;
+    if (e != null) continue;
     while (true) use(e);
   } while (index++ != 2);
   // 'c' must have been saved in the environment.
   Expect.equals(c, 42);
 }
 
 void testInForLoop() {
   var c = get42();
   for (int i = 0; i < 10; i++) {
     var e = getNonInt();
     Expect.equals(42, e + 2);
-    if (e !== null) continue;
+    if (e != null) continue;
     while (true) use(e);
   }
   // 'c' must have been saved in the environment.
   Expect.equals(c, 42);
 }
 
 main() {
   testInWhileLoop();
   testInDoWhileLoop();
   testInForLoop();
   testInNestedWhileLoop();
   testInNestedWhileLoop2();
   testInNestedWhileLoop3();
 }