(replaceRootField: StringAdd).self
(replaceRootField: StringFormat).self
(replaceRootField: ArrowAssoc[ReplaceRootField]).x
(Since version 2.10.0) Use leftOfArrow
instead
(replaceRootField: Ensuring[ReplaceRootField]).x
(Since version 2.10.0) Use resultOfEnsuring
instead
(Since version 0.12-RC5) Use reactivemongo.api.collections.GenericCollection.aggregateWith