anchor.diff:          "with";
           "function";
           "->";
  -        "when"]
  +        "when";
  +        @"//"]
   
       // Check the intial state of the reserved words.
       let initialResult = NHol.printer.reserved_words()
  +//    printfn "Reserved words - expected: %A" reserved_words_initial
  +//    printfn "Reserved words - result: %A" initialResult
       NUnit.Framework.CollectionAssert.AreEquivalent(initialResult, reserved_words_initial)
   
       let reserved_words_added = [
  
positive.code:         "function";
          "->";
          "when";
          "TeSt";
          "two words"
          ]
  
negative.code:     // Remove added values returning reserved words back to inital state.
      NHol.printer.unreserve_words ["TeSt"; "two words"]
      let removeResult = NHol.printer.reserved_words()
  //    printfn "Reserved words - expected: %A" reserved_words_initial
  //    printfn "Reserved words - result: %A" removeResult
      NUnit.Framework.CollectionAssert.AreEquivalent(removeResult, reserved_words_initial)
  
  (* is_reserved_word  tests *)
  