Add unhandledExceptionCallback to streamSpawnFunction.

sdk/lib/isolate/base.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.
 
 part of dart.isolate;
 
 class IsolateSpawnException implements Exception {
   const IsolateSpawnException(String this._s);
   String toString() => "IsolateSpawnException: '$_s'";
   final String _s;
@@ skipping 13 matching lines @@
  * argument must be a static top-level function or a static method that takes no
  * arguments. It is illegal to pass a function closure.
  *
  * When any isolate starts (even the main script of the application), a default
  * [ReceivePort] is created for it. This port is available from the top-level
  * getter [port] defined in this library.
  *
  * [spawnFunction] returns a [SendPort] derived from the child isolate's default
  * port.
  *
+ * The optional [unhandledExceptionCallback] argument is invoked whenever an
+ * exception inside the isolate is unhandled. It can be seen as a big
+ * `try/catch` around everything that is executed inside the isolate. The
+ * callback should return `true` when it was able to handled the exception.
+ *
  * See comments at the top of this library for more details.
  */
 SendPort spawnFunction(void topLevelFunction(),
-    [bool UnhandledExceptionCallback(IsolateUnhandledException e)])
-    => _Isolate.spawnFunction(topLevelFunction, UnhandledExceptionCallback);
+    [bool unhandledExceptionCallback(IsolateUnhandledException e)])
+    => _Isolate.spawnFunction(topLevelFunction, unhandledExceptionCallback);
 
 /**
  * Creates and spawns an isolate whose code is available at [uri].  Like with
  * [spawnFunction], the child isolate will have a default [ReceivePort], and a
  * this function returns a [SendPort] derived from it.
  *
  * See comments at the top of this library for more details.
  */
 SendPort spawnUri(String uri) => _Isolate.spawnUri(uri);
 
@@ skipping 115 matching lines @@
    */
   int get hashCode;
 }
 
 // The VM doesn't support accessing external globals in the same library. We
 // therefore create this wrapper class.
 // TODO(6997): Don't go through static class for external variables.
 abstract class _Isolate {
   external static ReceivePort get port;
   external static SendPort spawnFunction(void topLevelFunction(),
-    [bool UnhandledExceptionCallback(IsolateUnhandledException e)]);
+    [bool unhandledExceptionCallback(IsolateUnhandledException e)]);
   external static SendPort spawnUri(String uri);
 }
 
 /**
  * Wraps unhandled exceptions thrown during isolate execution. It is
  * used to show both the error message and the stack trace for unhandled
  * exceptions.
  */
 class IsolateUnhandledException implements Exception {
   /** Message being handled when exception occurred. */
   final message;
 
   /** Wrapped exception. */
   final source;
 
   /** Trace for the wrapped exception. */
   final Object stackTrace;
 
   const IsolateUnhandledException(this.message, this.source, this.stackTrace);
 
   String toString() {
     return 'IsolateUnhandledException: exception while handling message: '
         '${message} \n  '
         '${source.toString().replaceAll("\n", "\n  ")}\n'
         'original stack trace:\n  '
         '${stackTrace.toString().replaceAll("\n","\n  ")}';
   }
 }