A lossy Result fold

aResult.fsx

// A lossy Result seq fold
let singleResult<'T,'U> (rs : Result<'T,'U> seq) : Result<'T seq,'U> =
    
    let folder (ts, us) r = 
        match r with
        | Ok t -> (Seq.append ts [|t|], us)
        | Error u -> (ts, Seq.append us [|u|])

    rs 
    |> Seq.fold folder (Seq.empty, Seq.empty)
    |> fun (ts, errs) ->
        if(errs |> Seq.isEmpty) then
            Ok ts
        else Error errs
    |> function 
        | Ok xs -> Ok xs 
        | Error errs -> Error (errs |> Seq.head)