whenOrNull<TResult extends Object?> method

@optionalTypeArgs TResult? whenOrNull<TResult extends Object?>(TResult? $default(int id, @JsonKey.new(name: 'created_at') @TimestampConverter() Jiffy createdAt, int customers, @JsonKey.new(name: 'isibook_spaces_id') int isibookSpacesId, @JsonKey.new(name: 'isibook_space_activity_id') int? isibookSpaceActivityId, @JsonKey.new(name: 'amount_payed') num amountPayed, @JsonKey.new(name: 'datetime_first_slot') @TimestampConverter() Jiffy datetimeFirstSlot, @JsonKey.new(name: 'datetime_last_slot') @TimestampConverter() Jiffy datetimeLastSlot, int points, num electronic, @JsonKey.new(name: 'cancel_at') @TimestampConverter() Jiffy? cancelAt, @JsonKey.new(name: 'isibook_space_activity') IsibookTransactionSpaceInfo? isibookSpaceActivity, @JsonKey.new(name: 'isibook_space') IsibookTransactionSpaceInfo? isibookSpace,)?)

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(
          int id,
          @JsonKey(name: 'created_at') @TimestampConverter() Jiffy createdAt,
          int customers,
          @JsonKey(name: 'isibook_spaces_id') int isibookSpacesId,
          @JsonKey(name: 'isibook_space_activity_id')
          int? isibookSpaceActivityId,
          @JsonKey(name: 'amount_payed') num amountPayed,
          @JsonKey(name: 'datetime_first_slot')
          @TimestampConverter()
          Jiffy datetimeFirstSlot,
          @JsonKey(name: 'datetime_last_slot')
          @TimestampConverter()
          Jiffy datetimeLastSlot,
          int points,
          num electronic,
          @JsonKey(name: 'cancel_at') @TimestampConverter() Jiffy? cancelAt,
          @JsonKey(name: 'isibook_space_activity')
          IsibookTransactionSpaceInfo? isibookSpaceActivity,
          @JsonKey(name: 'isibook_space')
          IsibookTransactionSpaceInfo? isibookSpace)?
      $default,
) {
  final _that = this;
  switch (_that) {
    case _IsibookTransaction() when $default != null:
      return $default(
          _that.id,
          _that.createdAt,
          _that.customers,
          _that.isibookSpacesId,
          _that.isibookSpaceActivityId,
          _that.amountPayed,
          _that.datetimeFirstSlot,
          _that.datetimeLastSlot,
          _that.points,
          _that.electronic,
          _that.cancelAt,
          _that.isibookSpaceActivity,
          _that.isibookSpace);
    case _:
      return null;
  }
}