Task<long> CountAsync(
	CancellationToken cancellationToken = null
)

Function CountAsync ( 
	Optional cancellationToken As CancellationToken = Nothing
) As Task(Of Long)

abstract CountAsync : 
        ?cancellationToken : CancellationToken 
(* Defaults:
        let _cancellationToken = defaultArg cancellationToken null
*)
-> Task<int64>