anchor.diff:      return '$name(${data.join("; ")})';
     }
   
  -  /// Accumulates a list of strings describing the current widget's fields, one
  -  /// field per string.
  -  ///
  -  /// Subclasses should override this to have their information included in
  -  /// [toString].
  +  /// Add additional information to the given description for use by [toString].
  +  ///
  +  /// This method makes it easier for subclasses to coordinate to provide a
  +  /// high-quality [toString] implementation. The [toString] implementation on
  +  /// the [State] base class calls [debugFillDescription] to collect useful
  +  /// information from subclasses to incorporate into its return value.
  +  ///
  +  /// If you override this, make sure to start your method with a call to
  +  /// `super.debugFillDescription(description)`.
     @protected
     @mustCallSuper
     void debugFillDescription(List<String> description) { }
  
positive.code:   Widget get widget => _widget;
    Widget _widget;
  
    /// The owner for this node (null if unattached).
    BuildOwner get owner => _owner;
    BuildOwner _owner;
  
  
negative.code:     return chain.join(' \u2190 ');
    }
  
    /// A short, textual description of this element.
    String toStringShort() {
      return widget != null ? '${widget.toStringShort()}' : '[$runtimeType]';
    }
  