anchor.diff:              else
                   Substring.Split.iter separator action (substring (str))
   
  -        /// Applies the given function to each of the substrings in the input string that are
  -        /// delimited by elements of a specified Unicode character array. The integer index
  -        /// applied to the function is the index of the substring within the virtual array of
  -        /// substrings in the input string. For example, if the newline character (\n) is used
  -        /// as the separator, the index of each substring would be the line number.
  +        /// <summary>
  +        /// Applies the given function to each of the substrings in the input string that are delimited by elements of a specified
  +        /// Unicode character array. The integer index applied to the function is the index of the substring within the virtual array
  +        /// of substrings in the input string. For example, if the newline character (\n) is used as the separator, the index of each
  +        /// substring would be the line number.
  +        /// </summary>
  +        /// <param name="separator"></param>
  +        /// <param name="action"></param>
  +        /// <param name="str"></param>
  +        /// <returns></returns>
           [<CompiledName("IterateIndexed")>]
           let iteri (separator : char[]) (action : int -> substring -> unit) (str : string) : unit =
               // Preconditions
  
positive.code:             // Create a new string from the chosen characters.
              ofArray chosenChars.[..chosenCount-1]
  
      /// Applies a function to each character in the string and the character which
      /// follows it, threading an accumulator argument through the computation.
      [<CompiledName("FoldPairwise")>]
      let foldPairwise (folder : 'State -> char -> char -> 'State) state (str : string) =
          // Preconditions
  
negative.code: 
          Substring.foldBack folder (substring (str)) state
  
      /// <summary>
      /// Applies the given function to pairs of characters drawn from matching indices in two strings, threading an accumulator argument
      /// through the computation. The two strings must have the same length, otherwise an <see cref="ArgumentException"/> is raised. If the
      /// input function is <c>f</c> and the characters are <c>c0...cN</c> and <c>d0...dN</c> then computes <c>f (...(f s c0 d0)...) cN d0</c>.
      /// </summary>
      /// <param name="folder"></param>
      /// <param name="state"></param>
      /// <param name="str1"></param>
      /// <param name="str2"></param>
      /// <returns></returns>
      [<CompiledName("Fold2")>]
      let fold2 (folder : 'State -> char -> char -> 'State) (state : 'State) (str1 : string) (str2 : string) : 'State =
          // Preconditions
  