whenOrNull<TResult extends Object?> method

@optionalTypeArgs TResult? whenOrNull<TResult extends Object?>(TResult? $default(String type, @ElementConverter.new() Element? card, @JsonKey.new(name: "au_becs_debit") @ElementConverter.new() Element? auBecsDebit, @ElementConverter.new() Element? fpx, @JsonKey.new(name: "fpx[bank]") String? fpxBank, @JsonKey.new(name: "netbanking[bank]") String? netbankingBank, @ElementConverter.new() Element? ideal, @JsonKey.new(name: "ideal[bank]") String? idealBank, @JsonKey.new(name: "sepa_debit") @ElementConverter.new() Element? sepaDebit, @JsonKey.new(name: "sepa_debit[iban]") String? sepaDebitIban, @JsonKey.new(name: "upi[vpa]") String? upiVpa, @JsonKey.new(name: "billing_details") BillingDetails? billingDetails,)?)

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 type, @ElementConverter()  Element? card, @JsonKey(name: "au_becs_debit")@ElementConverter()  Element? auBecsDebit, @ElementConverter()  Element? fpx, @JsonKey(name: "fpx[bank]")  String? fpxBank, @JsonKey(name: "netbanking[bank]")  String? netbankingBank, @ElementConverter()  Element? ideal, @JsonKey(name: "ideal[bank]")  String? idealBank, @JsonKey(name: "sepa_debit")@ElementConverter()  Element? sepaDebit, @JsonKey(name: "sepa_debit[iban]")  String? sepaDebitIban, @JsonKey(name: "upi[vpa]")  String? upiVpa, @JsonKey(name: "billing_details")  BillingDetails? billingDetails)?  $default,) {final _that = this;
switch (_that) {
case _CreatePaymentMethodData() when $default != null:
return $default(_that.type,_that.card,_that.auBecsDebit,_that.fpx,_that.fpxBank,_that.netbankingBank,_that.ideal,_that.idealBank,_that.sepaDebit,_that.sepaDebitIban,_that.upiVpa,_that.billingDetails);case _:
  return null;

}
}