Don't use redirecting factories with type arguments.

dart/sdk/lib/async/stream.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.async;
 
 // -------------------------------------------------------------------
 // Core Stream types
 // -------------------------------------------------------------------
 
@@ skipping 12 matching lines @@
       });
     return controller.stream;
   }
 
   /**
    * Stream that outputs events from the [sources] in cyclic order.
    *
    * The merged streams are paused and resumed in order to ensure the proper
    * order of output events.
    */
-  factory Stream.cyclic(Iterable<Stream> sources) = CyclicScheduleStream<T>;
+  factory Stream.cyclic(Iterable<Stream> sources) {
+    return new CyclicScheduleStream<T>(sources);
+  }
 
  /**
    * Create a stream that forwards data from the highest priority active source.
    *
    * Sources are provided in order of increasing priority, and only data from
    * the highest priority source stream that has provided data are output
    * on the created stream.
    *
    * Errors from the most recent active stream, and any higher priority stream,
    * are forwarded to the created stream.
    *
    * If a higher priority source stream completes without providing data,
    * it will have no effect on lower priority streams.
    */
-  factory Stream.superceding(Iterable<Stream<T>> sources) = SupercedeStream<T>;
+  factory Stream.superceding(Iterable<Stream<T>> sources) {
+    return new SupercedeStream<T>(sources);
+  }
 
   /**
    * Add a subscription to this stream.
    *
    * On each data event from this stream, the subscribers [onData] handler
    * is called. If [onData] is null, nothing happens.
    *
    * On errors from this stream, the [onError] handler is given a
    * [AsyncError] object describing the error.
    *
@@ skipping 770 matching lines @@
     sink.signalError(error);
   }
 
   /**
    * Handle an incoming done event.
    */
   void handleDone(StreamSink<T> sink) {
     sink.close();
   }
 }