anchor.diff:  
       // Verify function input form and human form match.
       let convertedForm = (NHol.parser.lex << NHol.lib.explode) externalForm  // Notice use of lex to convert string to lexcode.
  -    printfn "convertedForm: %A" convertedForm
  +//    printfn "external form: %A" externalForm
  +//    printfn "internal form: %A" internalForm
  +//    printfn "converted form: %A" convertedForm
       Assert.AreEqual(convertedForm, internalForm)
   
       // Verify result of function
       let lexcodeParser : lexcode list -> lexcode list * lexcode list = NHol.parser.many intLexcodeParser
       let (current, rest) = lexcodeParser internalForm
  -//    printfn "current: %A" current
  -//    printfn "rest: %A" rest
  +//    printfn "expected result: %A %A" currentResult restResult
  +//    printfn "function result: %A %A" current rest
       Assert.AreEqual(current, currentResult)
       Assert.AreEqual(rest, restResult)
   
  
positive.code: //    printfn "test2: %A" test2
  
      let convertedForm = (NHol.parser.lex << NHol.lib.explode) externalForm  // Notice use of lex to convert string to lexcode.
  //    printfn "convertedForm: %A" convertedForm
      Assert.AreEqual(convertedForm, internalForm)
  
      // Verify result of function
      let lexcodeParser : lexcode list -> lexcode * lexcode list = NHol.parser.some isLexcodeNum
      let (current, rest) = lexcodeParser internalForm
  //    printfn "current: %A" current
  //    printfn "rest: %A" rest
      Assert.AreEqual(current, currentResult)
      Assert.AreEqual(rest, restResult)
  
  
negative.code: 
      // Verify function input form and human form match.
      let convertedForm = NHol.lib.explode externalForm
  //    printfn "external form: %A" externalForm
  //    printfn "internal form: %A" internalForm
  //    printfn "converted form: %A" convertedForm
      Assert.AreEqual(convertedForm, internalForm)
  
      // Verify result of function
      let stringParser : string list -> string list * string list = NHol.parser.possibly intParser
      let (current, rest) = stringParser internalForm
  //    printfn "expected result: %A %A" currentResult restResult
  //    printfn "function result: %A %A" current rest
      Assert.AreEqual(current, currentResult)
      Assert.AreEqual(rest, restResult)
  
  