anchor.diff:    ///
     /// {@macro flutter.widgets.navigator.pushNamed}
     ///
  +  /// {@macro flutter.widgets.navigator.pushNamed.returnValue}
  +  ///
     /// {@macro flutter.widgets.Navigator.pushNamed}
     ///
     /// {@tool snippet}
  
positive.code:   /// finished animating in.
    ///
    /// {@macro flutter.widgets.navigator.pushReplacementNamed}
    ///
    /// {@macro flutter.widgets.Navigator.pushNamed}
    ///
  
negative.code:   /// routes until the `predicate` returns true.
    ///
    /// {@macro flutter.widgets.navigator.pushAndRemoveUntil}
    ///
    /// {@macro flutter.widgets.navigator.pushNamed.returnValue}
    ///
    /// {@tool snippet}
    ///
  