anchor.diff:  (* Combinators.                                                              *)
   (* ------------------------------------------------------------------------- *)
   
  +(* OPTIMIZE :   The functions below should (probably) all be inlined; alternatively,
  +                some can be replaced (used as aliases for) F# intrinsic functions. *)
   let curry f x y = f(x, y)
   let uncurry f (x, y) = f x y
   let I x = x
  
positive.code: *)
  
  #if INTERACTIVE
  #else
  /// Various useful general library functions.
  module NHol.lib
  
negative.code: (* ------------------------------------------------------------------------- *)
  
  // TODO : Move this into FSharp.Compatibility.OCaml
  module Ratio =
      open FSharp.Compatibility.OCaml
      open FSharp.Compatibility.OCaml.Num
  
      // NOTE : not sure what kind of normalization should be done here
      let normalize_ratio x = x
      let numerator_ratio(r : Ratio.ratio) = r.Numerator
  