anchor.diff:  /// If your message provides obvious advice that is always applicable, it is an
   /// [ErrorDescription] not a hint.
   ///
  +/// In debug builds, values interpolated into the `message` are
  +/// expanded and placed into [value], which is of type [List<Object>].
  +/// This allows IDEs to examine values interpolated into error messages.
  +///
   /// See also:
   ///
   ///  * [ErrorSummary], which provides a short (one line) description of the
  
positive.code: /// Use [ErrorDescription] for any part of an error message where neither
  /// [ErrorSummary] or [ErrorHint] is appropriate.
  ///
  /// See also:
  ///
  ///  * [ErrorSummary], which provides a short (one line) description of the
  
negative.code: 
  // Examples can assume:
  // String runtimeType;
  // bool draconisAlive;
  // bool draconisAmulet;
  // Diagnosticable draconis;
  
  /// Signature for [FlutterError.onError] handler.
  typedef FlutterExceptionHandler = void Function(FlutterErrorDetails details);
  