anchor.diff:                  ilTree := {!ilTree with grammar = constr.Fix grammar}
           !ilTree
   
  -    [<Test>]
  -    member test.``Right generation of file`` () =  
  -        let inFile = "calc.yrd"
  +    let tetsFun inFile =
           let resultFile = System.IO.Path.GetFileNameWithoutExtension inFile + ".fs"
           let inFullPath = Path.Combine(basePath, inFile)
           let resultFullPath = Path.Combine(basePath, resultFile)
  
positive.code:         filesAreEqual resultFullPath expectedFullPath      
  
      [<Test>]
      member test.``Right calculation`` () = 
          let compCalc = ws >>. expr  .>> eof
          let gogo s = run compCalc s
          let checkInPut =
              function
              | Success (v, _, _)  -> Assert.AreEqual(v.ToString(), "56")
              | Failure (msg, err, _) -> printf "%s" msg; failwith msg
          ( gogo  "2+2*3**(2+1)" ) |> checkInPut 
  
      [<Test>]
      member test.``Test for literals`` () =
          let inFile = "literals.yrd"
          let resultFile = System.IO.Path.GetFileNameWithoutExtension inFile + ".fs"
          let inFullPath = Path.Combine(basePath, inFile)
          let resultFullPath = Path.Combine(basePath, resultFile)
          let expectedFullPath = Path.Combine [|basePath; generated; resultFile|]
          let il = parser.ParseGrammar inFullPath |> fixIl
          let code = iGenerator.Generate il
          System.IO.File.Exists resultFullPath |> Assert.IsTrue
          filesAreEqual resultFullPath expectedFullPath
  
      [<Test>]
      member test.``Right calculation for literals`` () = 
  
negative.code:         let gogo s = run compCalc s
          let checkInPut =
              function
              | Success (v, _, _)  -> Assert.AreEqual("aaaa", v.ToString())
              | Failure (msg, err, _) -> printf "%s" msg; failwith msg
          (gogo  "aaaa") |> checkInPut 