public static Task<Nullable<float>> SumAsync(
	this IMongoQueryable<Nullable<float>> source,
	CancellationToken cancellationToken = null
)

<ExtensionAttribute>
Public Shared Function SumAsync ( 
	source As IMongoQueryable(Of Nullable(Of Single)),
	Optional cancellationToken As CancellationToken = Nothing
) As Task(Of Nullable(Of Single))

[<ExtensionAttribute>]
static member SumAsync : 
        source : IMongoQueryable<Nullable<float32>> * 
        ?cancellationToken : CancellationToken 
(* Defaults:
        let _cancellationToken = defaultArg cancellationToken null
*)
-> Task<Nullable<float32>>