whenOrNull<TResult extends Object?> method

  1. @optionalTypeArgs
TResult? whenOrNull<TResult extends Object?>({
  1. TResult? googlePay(
    1. GooglePayParams googlePayParams,
    2. GooglePayPaymentMethodParams googlePayPaymentMethodParams
    )?,
  2. TResult? applePay(
    1. ApplePayParams applePayParams
    )?,
  3. TResult? web(
    1. PlatformPayWebPaymentRequestCreateOptions options
    )?,
})

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( GooglePayParams googlePayParams,  GooglePayPaymentMethodParams googlePayPaymentMethodParams)?  googlePay,TResult? Function( ApplePayParams applePayParams)?  applePay,TResult? Function( PlatformPayWebPaymentRequestCreateOptions options)?  web,}) {final _that = this;
switch (_that) {
case PlatformPayPaymentMethodParamsGooglePay() when googlePay != null:
return googlePay(_that.googlePayParams,_that.googlePayPaymentMethodParams);case PlatformPayPaymentMethodParamsApplePay() when applePay != null:
return applePay(_that.applePayParams);case PlatformPayPaymentMethodParamsWeb() when web != null:
return web(_that.options);case _:
  return null;

}
}