anchor.diff:    }
   }
   
  +///
   /// The sink returned by the generating function given to
   /// [IsolateStream.fromSink].
  +///
   class IsolateGeneratorSink<T> implements Sink<T> {
     _SendPortAdapter _dest;
     bool _closed = false;
  
positive.code: import 'dart:typed_data';
  import 'package:async/async.dart'; // Only for Cipher*Stream
  
  ///  A [Stream] whose content is generated by a function that runs in a separate
  ///  [Isolate].  A flow control protocol is established to throttle the
  ///  generating function, if needed, so that the [SendPort]/[ReceivePort] buffer
  ///  doesn't get overly large.
  class IsolateStream<T, A> extends DelegatingStream<T> {
    final _IsolateStreamGenerator<T, A> _isolateManager;
  
  
negative.code:   }
  }
  
  ///
  /// A convenience implementation of the common case of an
  /// `IsolateStream<Uint8List>`.
  /// This can be useful for generating a stream that is large -- many GB, or
  