whenOrNull<TResult extends Object?> method

@optionalTypeArgs TResult? whenOrNull<TResult extends Object?>(TResult? $default(int userId, Sub2ApiDecimal todayActualCost, Sub2ApiDecimal totalActualCost, List<Sub2ApiAdminPlatformUsage>? byPlatform,)?)

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 userId,
    Sub2ApiDecimal todayActualCost,
    Sub2ApiDecimal totalActualCost,
    List<Sub2ApiAdminPlatformUsage>? byPlatform,
  )?
  $default,
) {
  final _that = this;
  switch (_that) {
    case _Sub2ApiAdminBatchUserUsageStats() when $default != null:
      return $default(
        _that.userId,
        _that.todayActualCost,
        _that.totalActualCost,
        _that.byPlatform,
      );
    case _:
      return null;
  }
}