public WriteConcern(
	Optional<WriteConcern. WValue> w = null,
	Optional<Nullable<TimeSpan>> wTimeout = null,
	Optional<Nullable<bool>> fsync = null,
	Optional<Nullable<bool>> journal = null
)

Public Sub New ( 
	Optional w As Optional(Of WriteConcern.WValue) = Nothing,
	Optional wTimeout As Optional(Of Nullable(Of TimeSpan)) = Nothing,
	Optional fsync As Optional(Of Nullable(Of Boolean)) = Nothing,
	Optional journal As Optional(Of Nullable(Of Boolean)) = Nothing
)

new : 
        ?w : Optional<WriteConcern. WValue> * 
        ?wTimeout : Optional<Nullable<TimeSpan>> * 
        ?fsync : Optional<Nullable<bool>> * 
        ?journal : Optional<Nullable<bool>> 
(* Defaults:
        let _w = defaultArg w null
        let _wTimeout = defaultArg wTimeout null
        let _fsync = defaultArg fsync null
        let _journal = defaultArg journal null
*)
-> WriteConcern