whenOrNull<TResult extends Object?> method

  1. @optionalTypeArgs
TResult? whenOrNull<TResult extends Object?>(
  1. TResult? $default(
    1. PPAmount? handlingFee,
    2. PPAmount? insurance,
    3. PPAmount? shippingAndHandling,
    4. PPAmount? shippingDiscount,
    5. PPAmount? subtotal,
    6. PPAmount? tax,
    7. PPAmount? total,
    )?
)

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(
          PPAmount? handlingFee,
          PPAmount? insurance,
          PPAmount? shippingAndHandling,
          PPAmount? shippingDiscount,
          PPAmount? subtotal,
          PPAmount? tax,
          PPAmount? total)?
      $default,
) {
  final _that = this;
  switch (_that) {
    case _CartAmounts() when $default != null:
      return $default(
          _that.handlingFee,
          _that.insurance,
          _that.shippingAndHandling,
          _that.shippingDiscount,
          _that.subtotal,
          _that.tax,
          _that.total);
    case _:
      return null;
  }
}