anchor.diff:    Future get done;
   }
   
  -/**
  - * Datagram package. Data sent to and received from datagram sockets
  - * contains the internet address and port of the destination or source
  - * togeter with the data.
  - */
  +/// A data packet which is received by a [RawDatagramSocket].
   class Datagram {
  +  /// The actual bytes of the message.
     Uint8List data;
  +
  +  /// The address of the socket which sends the data.
     InternetAddress address;
  +
  +  /// The port of the socket which sends the data.
     int port;
   
     Datagram(this.data, this.address, this.port);
  
positive.code:    * distributed over multiple isolates this way.
     */
    external static Future<RawServerSocket> bind(address, int port,
        {int backlog: 0, bool v6Only: false, bool shared: false});
  
    /**
     * Returns the port used by this socket.
  
negative.code:   void setRawOption(RawSocketOption option);
  }
  
  /// Exception thrown when a socket operation fails.
  class SocketException implements IOException {
    /// Description of the error.
    final String message;
  
    /// The underlying OS error.
    ///
    /// If this exception is not thrown due to an OS error, the value is `null`.
    final OSError? osError;
  
    /// The address of the socket giving rise to the exception.
    ///
    /// This is either the source or destination address of a socket,
    /// or it can be `null` if no socket end-point was involved in the cause of
    /// the exception.
    final InternetAddress? address;
  
    /// The port of the socket giving rise to the exception.
    ///
    /// This is either the source or destination address of a socket,
    /// or it can be `null` if no socket end-point was involved in the cause of
    /// the exception.
    final int? port;
  
    /// Creates a [SocketException] with the provided values.
    const SocketException(this.message, {this.osError, this.address, this.port});
  
    /// Creates an exception reporting that a socket was used after it was closed.
    const SocketException.closed()
        : message = 'Socket has been closed',
          osError = null,
  