anchor.diff:  (* and analogous 0b... for binary.                                           *)
   (* ------------------------------------------------------------------------- *)
   
  +/// Converts decimal, hex or binary string representation into number.
   let num_of_string = 
       let values = 
           ["0", 0;
  
positive.code:         if p(h) then h
          else find p t
  
  // OPTIMIZE : Make this an alias for List.tryFind.
  let rec tryfind f l = 
      match l with
  
negative.code: (* Apply a destructor as many times as elements in list.                     *)
  (* ------------------------------------------------------------------------- *)
  
  /// Applies a destructor in right-associative mode a specified number of times.
  let rec nsplit dest clist x = 
      if clist = [] then [], x
      else 
  