whenOrNull<TResult extends Object?> method

@optionalTypeArgs TResult? whenOrNull<TResult extends Object?>(TResult? $default(String placeholder, String title, String okBtnText, String cancelBtnText, bool disableOkButton(int value)?, String? errorMessage(int value)?, TextStyle? okButtonTextStyle, TextStyle? cancelButtonTextStyle,)?)

A variant of when that fallback to returning null

It is equivalent to doing:

switch (sealedClass) {
  case Subclass(:final field):
    return ...;
  case _:
    return null;
}

Implementation

@optionalTypeArgs
TResult? whenOrNull<TResult extends Object?>(
  TResult? Function(
          String placeholder,
          String title,
          String okBtnText,
          String cancelBtnText,
          @igFreezedJson bool Function(int value)? disableOkButton,
          @igFreezedJson String? Function(int value)? errorMessage,
          @igFreezedJson TextStyle? okButtonTextStyle,
          @igFreezedJson TextStyle? cancelButtonTextStyle)?
      $default,
) {
  final _that = this;
  switch (_that) {
    case _AskIntDialogParams() when $default != null:
      return $default(
          _that.placeholder,
          _that.title,
          _that.okBtnText,
          _that.cancelBtnText,
          _that.disableOkButton,
          _that.errorMessage,
          _that.okButtonTextStyle,
          _that.cancelButtonTextStyle);
    case _:
      return null;
  }
}