anchor.diff:          proc.StartInfo.RedirectStandardOutput <- true
           proc.StartInfo.RedirectStandardError <- true
           proc.ErrorDataReceived.Add(fun d -> 
  -            if d.Data <> null then eprintfn "%s" d.Data)
  +            if not (isNull d.Data) then eprintfn "%s" d.Data)
           proc.OutputDataReceived.Add(fun d -> 
  -            if d.Data <> null then printfn "%s" d.Data)
  +            if not (isNull d.Data) then printfn "%s" d.Data)
           proc.Start() |> ignore
           proc.BeginErrorReadLine()
           proc.BeginOutputReadLine()
  
positive.code:         execProcess "git" "commit -m \"Add new posts [skip ci]\""
          execProcess "git" "push origin master"
  
      let bakeSite =
          System.Threading.Thread.CurrentThread.CurrentCulture <- System.Globalization.CultureInfo.CreateSpecificCulture("fr-FR")
          execProcess @"C:\tools\Pretzel\Pretzel" "bake site" 
  
  
negative.code:     let isBuildForced _ =
          let commitMessage = Environment.GetEnvironmentVariable("APPVEYOR_REPO_COMMIT_MESSAGE")
          let forcedBuild = Environment.GetEnvironmentVariable("APPVEYOR_FORCED_BUILD")
          (not (isNull commitMessage) && commitMessage.ToLowerInvariant().Contains("[force]") )
                  || (not (isNull forcedBuild) && forcedBuild.ToLowerInvariant() = "true")
  
      let generatePosts configFileName isForced = 
          printfn "start posts generation"
  