sdk/lib/js/dartium/js_dartium.dart - sdk.git - Git at Google

 // Copyright (c) 2013, 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.

 /**
  * The js.dart library provides simple JavaScript invocation from Dart that
  * works on both Dartium and on other modern browsers via Dart2JS.
  *
  * It provides a model based on scoped [JsObject] objects.  Proxies give Dart
  * code access to JavaScript objects, fields, and functions as well as the
  * ability to pass Dart objects and functions to JavaScript functions.  Scopes
  * enable developers to use proxies without memory leaks - a common challenge
  * with cross-runtime interoperation.
  *
  * The top-level [context] getter provides a [JsObject] to the global JavaScript
  * context for the page your Dart code is running on.  In the following example:
  *
  *     import 'dart:js';
  *
  *     void main() {
  *       context.callMethod('alert', ['Hello from Dart via JavaScript']);
  *     }
  *
  * context['alert'] creates a proxy to the top-level alert function in
  * JavaScript.  It is invoked from Dart as a regular function that forwards to
  * the underlying JavaScript one.  By default, proxies are released when
  * the currently executing event completes, e.g., when main is completes
  * in this example.
  *
  * The library also enables JavaScript proxies to Dart objects and functions.
  * For example, the following Dart code:
  *
  *     context['dartCallback'] = new Callback.once((x) => print(x*2));
  *
  * defines a top-level JavaScript function 'dartCallback' that is a proxy to
  * the corresponding Dart function.  The [Callback.once] constructor allows the
  * proxy to the Dart function to be retained across multiple events;
  * instead it is released after the first invocation.  (This is a common
  * pattern for asychronous callbacks.)
  *
  * Note, parameters and return values are intuitively passed by value for
  * primitives and by reference for non-primitives.  In the latter case, the
  * references are automatically wrapped and unwrapped as proxies by the library.
  *
  * This library also allows construction of JavaScripts objects given a
  * [JsObject] to a corresponding JavaScript constructor.  For example, if the
  * following JavaScript is loaded on the page:
  *
  *     function Foo(x) {
  *       this.x = x;
  *     }
  *
  *     Foo.prototype.add = function(other) {
  *       return new Foo(this.x + other.x);
  *     }
  *
  * then, the following Dart:
  *
  *     var foo = new JsObject(context['Foo'], [42]);
  *     var foo2 = foo.callMethod('add', [foo]);
  *     print(foo2['x']);
  *
  * will construct a JavaScript Foo object with the parameter 42, invoke its
  * add method, and return a [JsObject] to a new Foo object whose x field is 84.
  */

 library dart.js;

 import 'dart:collection' show HashMap;
 import 'dart:html';
 import 'dart:isolate';

 // Global ports to manage communication from Dart to JS.

 SendPortSync _jsPortSync = window.lookupPort('dart-js-context');
 SendPortSync _jsPortCreate = window.lookupPort('dart-js-create');
 SendPortSync _jsPortInstanceof = window.lookupPort('dart-js-instanceof');
 SendPortSync _jsPortDeleteProperty = window.lookupPort('dart-js-delete-property');
 SendPortSync _jsPortConvert = window.lookupPort('dart-js-convert');

 final String _objectIdPrefix = 'dart-obj-ref';
 final String _functionIdPrefix = 'dart-fun-ref';
 final _objectTable = new _ObjectTable();
 final _functionTable = new _ObjectTable.forFunctions();

 // Port to handle and forward requests to the underlying Dart objects.
 // A remote proxy is uniquely identified by an ID and SendPortSync.
 ReceivePortSync _port = new ReceivePortSync()
     ..receive((msg) {
       try {
         var id = msg[0];
         var method = msg[1];
         if (method == '#call') {
           var receiver = _getObjectTable(id).get(id);
           var result;
           if (receiver is Function) {
             // remove the first argument, which is 'this', but never
             // used for a raw function
             var args = msg[2].sublist(1).map(_deserialize).toList();
             result = Function.apply(receiver, args);
           } else if (receiver is Callback) {
             var args = msg[2].map(_deserialize).toList();
             result = receiver._call(args);
           } else {
             throw new StateError('bad function type: $receiver');
           }
           return ['return', _serialize(result)];
         } else {
           // TODO(vsm): Support a mechanism to register a handler here.
           throw 'Invocation unsupported on non-function Dart proxies';
         }
       } catch (e) {
         // TODO(vsm): callSync should just handle exceptions itself.
         return ['throws', '$e'];
       }
     });

 _ObjectTable _getObjectTable(String id) {
   if (id.startsWith(_functionIdPrefix)) return _functionTable;
   if (id.startsWith(_objectIdPrefix)) return _objectTable;
   throw new ArgumentError('internal error: invalid object id: $id');
 }

 JsObject _context;

 /**
  * Returns a proxy to the global JavaScript context for this page.
  */
 JsObject get context {
   if (_context == null) {
     var port = _jsPortSync;
     if (port == null) {
       return null;
     }
     _context = _deserialize(_jsPortSync.callSync([]));
   }
   return _context;
 }

 /**
  * Converts a json-like [data] to a JavaScript map or array and return a
  * [JsObject] to it.
  */
 JsObject jsify(dynamic data) => data == null ? null : new JsObject._json(data);

 /**
  * Converts a local Dart function to a callback that can be passed to
  * JavaScript.
  */
 class Callback implements Serializable<JsFunction> {
   final bool _withThis;
   final Function _function;
   JsFunction _jsFunction;

   Callback._(this._function, this._withThis) {
     var id = _functionTable.add(this);
     _jsFunction = new JsFunction._internal(_port.toSendPort(), id);
   }

   factory Callback(Function f) => new Callback._(f, false);
   factory Callback.withThis(Function f) => new Callback._(f, true);

   dynamic _call(List args) {
     var arguments = (_withThis) ? args : args.sublist(1);
     return Function.apply(_function, arguments);
   }

   JsFunction toJs() => _jsFunction;
 }

 /**
  * Proxies to JavaScript objects.
  */
 class JsObject implements Serializable<JsObject> {
   final SendPortSync _port;
   final String _id;

   /**
    * Constructs a [JsObject] to a new JavaScript object by invoking a (proxy to
    * a) JavaScript [constructor].  The [arguments] list should contain either
    * primitive values, DOM elements, or Proxies.
    */
   factory JsObject(Serializable<JsFunction> constructor, [List arguments]) {
     final params = [constructor];
     if (arguments != null) params.addAll(arguments);
     final serialized = params.map(_serialize).toList();
     final result = _jsPortCreate.callSync(serialized);
     return _deserialize(result);
   }

   /**
    * Constructs a [JsObject] to a new JavaScript map or list created defined via
    * Dart map or list.
    */
   factory JsObject._json(data) => _convert(data);

   static _convert(data) =>
       _deserialize(_jsPortConvert.callSync(_serializeDataTree(data)));

   static _serializeDataTree(data) {
     if (data is Map) {
       final entries = new List();
       for (var key in data.keys) {
         entries.add([key, _serializeDataTree(data[key])]);
       }
       return ['map', entries];
     } else if (data is Iterable) {
       return ['list', data.map(_serializeDataTree).toList()];
     } else {
       return ['simple', _serialize(data)];
     }
   }

   JsObject._internal(this._port, this._id);

   JsObject toJs() => this;

   // Resolve whether this is needed.
   operator[](arg) => _forward(this, '[]', 'method', [ arg ]);

   // Resolve whether this is needed.
   operator[]=(key, value) => _forward(this, '[]=', 'method', [ key, value ]);

   int get hashCode => _id.hashCode;

   // Test if this is equivalent to another Proxy.  This essentially
   // maps to JavaScript's === operator.
   operator==(other) => other is JsObject && this._id == other._id;

   /**
    * Check if this [JsObject] has a [name] property.
    */
   bool hasProperty(String name) => _forward(this, name, 'hasProperty', []);

   /**
    * Delete the [name] property.
    */
   void deleteProperty(String name) {
     _jsPortDeleteProperty.callSync([this, name].map(_serialize).toList());
   }

   /**
    * Check if this [JsObject] is instance of [type].
    */
   bool instanceof(Serializable<JsFunction> type) =>
       _jsPortInstanceof.callSync([this, type].map(_serialize).toList());

   String toString() {
     try {
       return _forward(this, 'toString', 'method', []);
     } catch(e) {
       return super.toString();
     }
   }

   callMethod(String name, [List args]) {
     return _forward(this, name, 'method', args != null ? args : []);
   }

   // Forward member accesses to the backing JavaScript object.
   static _forward(JsObject receiver, String member, String kind, List args) {
     var result = receiver._port.callSync([receiver._id, member, kind,
                                           args.map(_serialize).toList()]);
     switch (result[0]) {
       case 'return': return _deserialize(result[1]);
       case 'throws': throw _deserialize(result[1]);
       case 'none':
           throw new NoSuchMethodError(receiver, new Symbol(member), args, {});
       default: throw 'Invalid return value';
     }
   }
 }

 /// A [JsObject] subtype to JavaScript functions.
 class JsFunction extends JsObject implements Serializable<JsFunction> {
   JsFunction._internal(SendPortSync port, String id)
       : super._internal(port, id);

   apply(thisArg, [List args]) {
     return JsObject._forward(this, '', 'apply',
         [thisArg]..addAll(args == null ? [] : args));
   }
 }

 /// Marker class used to indicate it is serializable to js. If a class is a
 /// [Serializable] the "toJs" method will be called and the result will be used
 /// as value.
 abstract class Serializable<T> {
   T toJs();
 }

 class _ObjectTable {
   final String name;
   final Map<String, Object> objects;
   final Map<Object, String> ids;
   int nextId = 0;

   // Creates a table that uses an identity Map to store IDs
   _ObjectTable()
     : name = _objectIdPrefix,
       objects = new HashMap<String, Object>(),
       ids = new HashMap<Object, String>.identity();

   // Creates a table that uses an equality-based Map to store IDs, since
   // closurized methods may be equal, but not identical
   _ObjectTable.forFunctions()
     : name = _functionIdPrefix,
       objects = new HashMap<String, Object>(),
       ids = new HashMap<Object, String>();

   // Adds a new object to the table. If [id] is not given, a new unique ID is
   // generated. Returns the ID.
   String add(Object o, {String id}) {
     // TODO(vsm): Cache x and reuse id.
     if (id == null) id = ids[o];
     if (id == null) id = '$name-${nextId++}';
     ids[o] = id;
     objects[id] = o;
     return id;
   }

   // Gets an object by ID.
   Object get(String id) => objects[id];

   bool contains(String id) => objects.containsKey(id);

   String getId(Object o) => ids[o];

   // Gets the current number of objects kept alive by this table.
   get count => objects.length;
 }

 // Dart serialization support.

 _serialize(var message) {
   if (message == null) {
     return null;  // Convert undefined to null.
   } else if (message is String ||
              message is num ||
              message is bool) {
     // Primitives are passed directly through.
     return message;
   } else if (message is SendPortSync) {
     // Non-proxied objects are serialized.
     return message;
   } else if (message is JsFunction) {
     // Remote function proxy.
     return ['funcref', message._id, message._port];
   } else if (message is JsObject) {
     // Remote object proxy.
     return ['objref', message._id, message._port];
   } else if (message is Serializable) {
     // use of result of toJs()
     return _serialize(message.toJs());
   } else if (message is Function) {
     var id = _functionTable.getId(message);
     if (id != null) {
       return ['funcref', id, _port.toSendPort()];
     }
     id = _functionTable.add(message);
     return ['funcref', id, _port.toSendPort()];
   } else {
     // Local object proxy.
     return ['objref', _objectTable.add(message), _port.toSendPort()];
   }
 }

 _deserialize(var message) {
   deserializeFunction(message) {
     var id = message[1];
     var port = message[2];
     if (port == _port.toSendPort()) {
       // Local function.
       return _functionTable.get(id);
     } else {
       // Remote function.
       var jsFunction = _functionTable.get(id);
       if (jsFunction == null) {
         jsFunction = new JsFunction._internal(port, id);
         _functionTable.add(jsFunction, id: id);
       }
       return jsFunction;
     }
   }

   deserializeObject(message) {
     var id = message[1];
     var port = message[2];
     if (port == _port.toSendPort()) {
       // Local object.
       return _objectTable.get(id);
     } else {
       // Remote object.
       var jsObject = _objectTable.get(id);
       if (jsObject == null) {
         jsObject = new JsObject._internal(port, id);
         _objectTable.add(jsObject, id: id);
       }
       return jsObject;
     }
   }

   if (message == null) {
     return null;  // Convert undefined to null.
   } else if (message is String ||
              message is num ||
              message is bool) {
     // Primitives are passed directly through.
     return message;
   } else if (message is SendPortSync) {
     // Serialized type.
     return message;
   }
   var tag = message[0];
   switch (tag) {
     case 'funcref': return deserializeFunction(message);
     case 'objref': return deserializeObject(message);
   }
   throw 'Unsupported serialized data: $message';
 }
	// Copyright (c) 2013, 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.

	/**
	* The js.dart library provides simple JavaScript invocation from Dart that
	* works on both Dartium and on other modern browsers via Dart2JS.
	*
	* It provides a model based on scoped [JsObject] objects. Proxies give Dart
	* code access to JavaScript objects, fields, and functions as well as the
	* ability to pass Dart objects and functions to JavaScript functions. Scopes
	* enable developers to use proxies without memory leaks - a common challenge
	* with cross-runtime interoperation.
	*
	* The top-level [context] getter provides a [JsObject] to the global JavaScript
	* context for the page your Dart code is running on. In the following example:
	*
	* import 'dart:js';
	*
	* void main() {
	* context.callMethod('alert', ['Hello from Dart via JavaScript']);
	* }
	*
	* context['alert'] creates a proxy to the top-level alert function in
	* JavaScript. It is invoked from Dart as a regular function that forwards to
	* the underlying JavaScript one. By default, proxies are released when
	* the currently executing event completes, e.g., when main is completes
	* in this example.
	*
	* The library also enables JavaScript proxies to Dart objects and functions.
	* For example, the following Dart code:
	*
	* context['dartCallback'] = new Callback.once((x) => print(x*2));
	*
	* defines a top-level JavaScript function 'dartCallback' that is a proxy to
	* the corresponding Dart function. The [Callback.once] constructor allows the
	* proxy to the Dart function to be retained across multiple events;
	* instead it is released after the first invocation. (This is a common
	* pattern for asychronous callbacks.)
	*
	* Note, parameters and return values are intuitively passed by value for
	* primitives and by reference for non-primitives. In the latter case, the
	* references are automatically wrapped and unwrapped as proxies by the library.
	*
	* This library also allows construction of JavaScripts objects given a
	* [JsObject] to a corresponding JavaScript constructor. For example, if the
	* following JavaScript is loaded on the page:
	*
	* function Foo(x) {
	* this.x = x;
	* }
	*
	* Foo.prototype.add = function(other) {
	* return new Foo(this.x + other.x);
	* }
	*
	* then, the following Dart:
	*
	* var foo = new JsObject(context['Foo'], [42]);
	* var foo2 = foo.callMethod('add', [foo]);
	* print(foo2['x']);
	*
	* will construct a JavaScript Foo object with the parameter 42, invoke its
	* add method, and return a [JsObject] to a new Foo object whose x field is 84.
	*/

	library dart.js;

	import 'dart:collection' show HashMap;
	import 'dart:html';
	import 'dart:isolate';

	// Global ports to manage communication from Dart to JS.

	SendPortSync _jsPortSync = window.lookupPort('dart-js-context');
	SendPortSync _jsPortCreate = window.lookupPort('dart-js-create');
	SendPortSync _jsPortInstanceof = window.lookupPort('dart-js-instanceof');
	SendPortSync _jsPortDeleteProperty = window.lookupPort('dart-js-delete-property');
	SendPortSync _jsPortConvert = window.lookupPort('dart-js-convert');

	final String _objectIdPrefix = 'dart-obj-ref';
	final String _functionIdPrefix = 'dart-fun-ref';
	final _objectTable = new _ObjectTable();
	final _functionTable = new _ObjectTable.forFunctions();

	// Port to handle and forward requests to the underlying Dart objects.
	// A remote proxy is uniquely identified by an ID and SendPortSync.
	ReceivePortSync _port = new ReceivePortSync()
	..receive((msg) {
	try {
	var id = msg[0];
	var method = msg[1];
	if (method == '#call') {
	var receiver = _getObjectTable(id).get(id);
	var result;
	if (receiver is Function) {
	// remove the first argument, which is 'this', but never
	// used for a raw function
	var args = msg[2].sublist(1).map(_deserialize).toList();
	result = Function.apply(receiver, args);
	} else if (receiver is Callback) {
	var args = msg[2].map(_deserialize).toList();
	result = receiver._call(args);
	} else {
	throw new StateError('bad function type: $receiver');
	}
	return ['return', _serialize(result)];
	} else {
	// TODO(vsm): Support a mechanism to register a handler here.
	throw 'Invocation unsupported on non-function Dart proxies';
	}
	} catch (e) {
	// TODO(vsm): callSync should just handle exceptions itself.
	return ['throws', '$e'];
	}
	});

	_ObjectTable _getObjectTable(String id) {
	if (id.startsWith(_functionIdPrefix)) return _functionTable;
	if (id.startsWith(_objectIdPrefix)) return _objectTable;
	throw new ArgumentError('internal error: invalid object id: $id');
	}

	JsObject _context;

	/**
	* Returns a proxy to the global JavaScript context for this page.
	*/
	JsObject get context {
	if (_context == null) {
	var port = _jsPortSync;
	if (port == null) {
	return null;
	}
	_context = _deserialize(_jsPortSync.callSync([]));
	}
	return _context;
	}

	/**
	* Converts a json-like [data] to a JavaScript map or array and return a
	* [JsObject] to it.
	*/
	JsObject jsify(dynamic data) => data == null ? null : new JsObject._json(data);

	/**
	* Converts a local Dart function to a callback that can be passed to
	* JavaScript.
	*/
	class Callback implements Serializable<JsFunction> {
	final bool _withThis;
	final Function _function;
	JsFunction _jsFunction;

	Callback._(this._function, this._withThis) {
	var id = _functionTable.add(this);
	_jsFunction = new JsFunction._internal(_port.toSendPort(), id);
	}

	factory Callback(Function f) => new Callback._(f, false);
	factory Callback.withThis(Function f) => new Callback._(f, true);

	dynamic _call(List args) {
	var arguments = (_withThis) ? args : args.sublist(1);
	return Function.apply(_function, arguments);
	}

	JsFunction toJs() => _jsFunction;
	}

	/**
	* Proxies to JavaScript objects.
	*/
	class JsObject implements Serializable<JsObject> {
	final SendPortSync _port;
	final String _id;

	/**
	* Constructs a [JsObject] to a new JavaScript object by invoking a (proxy to
	* a) JavaScript [constructor]. The [arguments] list should contain either
	* primitive values, DOM elements, or Proxies.
	*/
	factory JsObject(Serializable<JsFunction> constructor, [List arguments]) {
	final params = [constructor];
	if (arguments != null) params.addAll(arguments);
	final serialized = params.map(_serialize).toList();
	final result = _jsPortCreate.callSync(serialized);
	return _deserialize(result);
	}

	/**
	* Constructs a [JsObject] to a new JavaScript map or list created defined via
	* Dart map or list.
	*/
	factory JsObject._json(data) => _convert(data);

	static _convert(data) =>
	_deserialize(_jsPortConvert.callSync(_serializeDataTree(data)));

	static _serializeDataTree(data) {
	if (data is Map) {
	final entries = new List();
	for (var key in data.keys) {
	entries.add([key, _serializeDataTree(data[key])]);
	}
	return ['map', entries];
	} else if (data is Iterable) {
	return ['list', data.map(_serializeDataTree).toList()];
	} else {
	return ['simple', _serialize(data)];
	}
	}

	JsObject._internal(this._port, this._id);

	JsObject toJs() => this;

	// Resolve whether this is needed.
	operator[](arg) => _forward(this, '[]', 'method', [ arg ]);

	// Resolve whether this is needed.
	operator[]=(key, value) => _forward(this, '[]=', 'method', [ key, value ]);

	int get hashCode => _id.hashCode;

	// Test if this is equivalent to another Proxy. This essentially
	// maps to JavaScript's === operator.
	operator==(other) => other is JsObject && this._id == other._id;

	/**
	* Check if this [JsObject] has a [name] property.
	*/
	bool hasProperty(String name) => _forward(this, name, 'hasProperty', []);

	/**
	* Delete the [name] property.
	*/
	void deleteProperty(String name) {
	_jsPortDeleteProperty.callSync([this, name].map(_serialize).toList());
	}

	/**
	* Check if this [JsObject] is instance of [type].
	*/
	bool instanceof(Serializable<JsFunction> type) =>
	_jsPortInstanceof.callSync([this, type].map(_serialize).toList());

	String toString() {
	try {
	return _forward(this, 'toString', 'method', []);
	} catch(e) {
	return super.toString();
	}
	}

	callMethod(String name, [List args]) {
	return _forward(this, name, 'method', args != null ? args : []);
	}

	// Forward member accesses to the backing JavaScript object.
	static _forward(JsObject receiver, String member, String kind, List args) {
	var result = receiver._port.callSync([receiver._id, member, kind,
	args.map(_serialize).toList()]);
	switch (result[0]) {
	case 'return': return _deserialize(result[1]);
	case 'throws': throw _deserialize(result[1]);
	case 'none':
	throw new NoSuchMethodError(receiver, new Symbol(member), args, {});
	default: throw 'Invalid return value';
	}
	}
	}

	/// A [JsObject] subtype to JavaScript functions.
	class JsFunction extends JsObject implements Serializable<JsFunction> {
	JsFunction._internal(SendPortSync port, String id)
	: super._internal(port, id);

	apply(thisArg, [List args]) {
	return JsObject._forward(this, '', 'apply',
	[thisArg]..addAll(args == null ? [] : args));
	}
	}

	/// Marker class used to indicate it is serializable to js. If a class is a
	/// [Serializable] the "toJs" method will be called and the result will be used
	/// as value.
	abstract class Serializable<T> {
	T toJs();
	}

	class _ObjectTable {
	final String name;
	final Map<String, Object> objects;
	final Map<Object, String> ids;
	int nextId = 0;

	// Creates a table that uses an identity Map to store IDs
	_ObjectTable()
	: name = _objectIdPrefix,
	objects = new HashMap<String, Object>(),
	ids = new HashMap<Object, String>.identity();

	// Creates a table that uses an equality-based Map to store IDs, since
	// closurized methods may be equal, but not identical
	_ObjectTable.forFunctions()
	: name = _functionIdPrefix,
	objects = new HashMap<String, Object>(),
	ids = new HashMap<Object, String>();

	// Adds a new object to the table. If [id] is not given, a new unique ID is
	// generated. Returns the ID.
	String add(Object o, {String id}) {
	// TODO(vsm): Cache x and reuse id.
	if (id == null) id = ids[o];
	if (id == null) id = '$name-${nextId++}';
	ids[o] = id;
	objects[id] = o;
	return id;
	}

	// Gets an object by ID.
	Object get(String id) => objects[id];

	bool contains(String id) => objects.containsKey(id);

	String getId(Object o) => ids[o];

	// Gets the current number of objects kept alive by this table.
	get count => objects.length;
	}

	// Dart serialization support.

	_serialize(var message) {
	if (message == null) {
	return null; // Convert undefined to null.
	} else if (message is String \|\|
	message is num \|\|
	message is bool) {
	// Primitives are passed directly through.
	return message;
	} else if (message is SendPortSync) {
	// Non-proxied objects are serialized.
	return message;
	} else if (message is JsFunction) {
	// Remote function proxy.
	return ['funcref', message._id, message._port];
	} else if (message is JsObject) {
	// Remote object proxy.
	return ['objref', message._id, message._port];
	} else if (message is Serializable) {
	// use of result of toJs()
	return _serialize(message.toJs());
	} else if (message is Function) {
	var id = _functionTable.getId(message);
	if (id != null) {
	return ['funcref', id, _port.toSendPort()];
	}
	id = _functionTable.add(message);
	return ['funcref', id, _port.toSendPort()];
	} else {
	// Local object proxy.
	return ['objref', _objectTable.add(message), _port.toSendPort()];
	}
	}

	_deserialize(var message) {
	deserializeFunction(message) {
	var id = message[1];
	var port = message[2];
	if (port == _port.toSendPort()) {
	// Local function.
	return _functionTable.get(id);
	} else {
	// Remote function.
	var jsFunction = _functionTable.get(id);
	if (jsFunction == null) {
	jsFunction = new JsFunction._internal(port, id);
	_functionTable.add(jsFunction, id: id);
	}
	return jsFunction;
	}
	}

	deserializeObject(message) {
	var id = message[1];
	var port = message[2];
	if (port == _port.toSendPort()) {
	// Local object.
	return _objectTable.get(id);
	} else {
	// Remote object.
	var jsObject = _objectTable.get(id);
	if (jsObject == null) {
	jsObject = new JsObject._internal(port, id);
	_objectTable.add(jsObject, id: id);
	}
	return jsObject;
	}
	}

	if (message == null) {
	return null; // Convert undefined to null.
	} else if (message is String \|\|
	message is num \|\|
	message is bool) {
	// Primitives are passed directly through.
	return message;
	} else if (message is SendPortSync) {
	// Serialized type.
	return message;
	}
	var tag = message[0];
	switch (tag) {
	case 'funcref': return deserializeFunction(message);
	case 'objref': return deserializeObject(message);
	}
	throw 'Unsupported serialized data: $message';
	}