whenOrNull<TResult extends Object?> method

  1. @optionalTypeArgs
TResult? whenOrNull<TResult extends Object?>({
  1. TResult? applePay(
    1. String orderTypeIdentifier,
    2. String orderIdentifier,
    3. String webServiceUrl,
    4. String authenticationToken,
    )?,
})

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 orderTypeIdentifier,  String orderIdentifier,  String webServiceUrl,  String authenticationToken)?  applePay,}) {final _that = this;
switch (_that) {
case _PlatformPayOrderDetails() when applePay != null:
return applePay(_that.orderTypeIdentifier,_that.orderIdentifier,_that.webServiceUrl,_that.authenticationToken);case _:
  return null;

}
}