SendPort + ReceivePort changes:

samples/leap/leap_leg.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.
 
 compilerIsolate(port) {
   Runner runner = new Runner();
   runner.init();
 
   port.receive((msg, replyTo) {
     replyTo.send(runner.update(msg));
   });
 }
 
 main() {
   dom.document.getElementById('status').innerHTML = 'Initializing compiler';
   final iframe = dom.document.getElementById('isolate');
-  setOutline(msg, _) {
+  setOutline(msg) {
     dom.document.getElementById('out').innerHTML = msg;
   }
   dom.spawnDomIsolate(iframe.contentWindow, 'compilerIsolate').then((sendPort) {
     update(_) {
       String text = dom.document.getElementById('code').innerText;
-      sendPort.call(text).receive(setOutline);
+      sendPort.call(text).then(setOutline);
       dom.document.getElementById('status').innerHTML = 'Ready';
     }
     update(null);
     final code = dom.document.getElementById('code');
     code.addEventListener('DOMSubtreeModified', update);
   });
 }
 
 class Runner {
   final LeapCompiler compiler;
@@ skipping 155 matching lines @@
     mainApp = new LibraryElement(script);
 
     universe.libraries.remove(script.uri.toString());
     Element element;
     withCurrentElement(mainApp, () {
         scanner.scan(mainApp);
       });
     return mainApp;
   }
 }