anchor.diff:      /// <param name="stream">The input stream.</param>
       /// <returns>true if all of the elements satisfies the predicate. Otherwise, returns false.</returns>
       let inline forall (predicate : 'T -> bool) (stream : Stream<'T>) : bool = 
  -        not <| exists (fun value -> not <| predicate value) stream+        not <| exists (fun value -> not <| predicate value) stream
  
positive.code:             streamf (fun value -> 
                  incr counter
                  if !counter > n then iterf value else true)
          Stream iter
  
  
  
negative.code: /// Provides basic operations on Streams.
  [<RequireQualifiedAccessAttribute>]
  module Stream =
  
      /// <summary>The empty stream.</summary>
      /// <returns>An empty stream.</returns>
      let empty : Stream<'T> =
          let iter iterf =
              let next () = false
              (ignore, next)
          Stream iter
  
      /// <summary>Creates a singleton stream.</summary>
      /// <param name="source">The singleton stream element</param>
      /// <returns>A stream of just the given element</returns>
      let inline singleton (source: 'T) : Stream<'T> =
          let iter iterf =
              let bulk () = iterf source |> ignore
              let next =
                  let pulled = ref false
                  fun () ->
                      if !pulled then false
                      else
                          iterf source |> ignore
                          pulled := true
                          true
              (bulk, next)
          Stream iter
             
      /// <summary>Wraps array as a stream.</summary>
      /// <param name="source">The input array.</param>
  