anchor.diff:                  acc <- st
                   true
           let dispose() = ()
  -        fromFunctions get next dispose
  +        fromFunctions current next dispose
   
   // [<CompilationRepresentation(CompilationRepresentationFlags.ModuleSuffix)>]
   // [<RequireQualifiedAccess>]
  
positive.code:     mkSeq (fun () -> Enumerator.unfold generator state)
  
  let empty () =
      delay (fun () -> Array.empty :> seq<'T>) // Enumerator.empty<_>())
  
  let singleton x =
      delay (fun () -> (Array.singleton x) :> seq<'T>) // Enumerator.singleton x)
  
  let ofArray (arr: 'T[]) =
      arr :> seq<'T>
  
negative.code:         let mutable started = false
          let mutable finished = false
          let mutable curr = None
          let current() =
              if not started then notStarted()
              elif finished then alreadyFinished()
              match curr with
  