whenOrNull<TResult extends Object?> method

  1. @optionalTypeArgs
TResult? whenOrNull<TResult extends Object?>({
  1. TResult? data(
    1. List<T> data,
    2. bool hasNext
    )?,
  2. TResult? error(
    1. String error
    )?,
})

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( List<T> data,  bool hasNext)?  data,TResult? Function( String error)?  error,}) {final _that = this;
switch (_that) {
case ListDataPickerData() when data != null:
return data(_that.data,_that.hasNext);case ListDataPickerError() when error != null:
return error(_that.error);case _:
  return null;

}
}