whenOrNull<TResult extends Object?> method

  1. @optionalTypeArgs
TResult? whenOrNull<TResult extends Object?>({
  1. TResult? createResult(
    1. CreateResult data
    )?,
  2. TResult? updateResult(
    1. UpdateResult data
    )?,
  3. TResult? deleteResult(
    1. DeleteResult data
    )?,
  4. TResult? unknown(
    1. Map<String, dynamic> data
    )?,
})

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( CreateResult data)?  createResult,TResult? Function( UpdateResult data)?  updateResult,TResult? Function( DeleteResult data)?  deleteResult,TResult? Function( Map<String, dynamic> data)?  unknown,}) {final _that = this;
switch (_that) {
case URepoApplyWritesResultsCreateResult() when createResult != null:
return createResult(_that.data);case URepoApplyWritesResultsUpdateResult() when updateResult != null:
return updateResult(_that.data);case URepoApplyWritesResultsDeleteResult() when deleteResult != null:
return deleteResult(_that.data);case URepoApplyWritesResultsUnknown() when unknown != null:
return unknown(_that.data);case _:
  return null;

}
}