(stdDevSampField: StringAdd).self
(stdDevSampField: StringFormat).self
(stdDevSampField: ArrowAssoc[AggregationFramework.StdDevSampField]).x
(Since version 2.10.0) Use leftOfArrow
instead
(stdDevSampField: Ensuring[AggregationFramework.StdDevSampField]).x
(Since version 2.10.0) Use resultOfEnsuring
instead
The $stdDevSamp for a single field (since MongoDB 3.2)