anchor.diff:      /// Extracts from a list of Choice all the Choice2Of2 elements. All the Choice2Of2 elements are extracted in order.
       let inline choice2s xs =
           let inline chooser a = match a with
  -                               | Choice1Of2 x -> Some x
  +                               | Choice2Of2 x -> Some x
                                  | _            -> None
           List.choose chooser xs
   
  
positive.code:     /// Extracts from a seq of Choice all the Choice2Of2 elements. All the Choice2Of2 elements are extracted in order.
      let inline choice2s xs =
          let inline chooser a = match a with
                                 | Choice1Of2 x -> Some x
                                 | _            -> None
          Seq.choose chooser xs
  
  
negative.code:     /// Extracts from an array of Choice all the Choice2Of2 elements. All the Choice2Of2 elements are extracted in order.
      let inline choice2s xs =
          let inline chooser a = match a with
                                 | Choice2Of2 x -> Some x
                                 | _            -> None
          Array.choose chooser xs
  
  