anchor.diff:          match result with 
           | Some _ -> result
           | None -> 
  -        // NOTE: we should probably probe the path here??
  +
           let result = 
               BackupInstallationProbePoints |> List.tryPick (fun x -> 
  +               Debug.tracef "Resolution" "BinFolderOfDefaultFSharpCore: Probing %s" x
                  let safeExists f = (try File.Exists(f) with _ -> false)
                  let file f = Path.Combine(Path.Combine(x,"bin"),f)
                  let exists f = safeExists(file f)
  
positive.code:   let internal tryFsharpiScript(url:string) =
      try
        let str = File.ReadAllText(url)
        let reg = new Regex("mono (\/.*)\/fsi\.exe")
        let res = reg.Match(str)
        if res.Success then Some(res.Groups.[1].Value) else None
      with e -> 
  
negative.code:         | None -> None
      with e -> 
        System.Diagnostics.Debug.Assert(false, "Error while determining default location of F# compiler")
        Debug.tracef "Resolution" "BinFolderOfDefaultFSharpCore: error %s" (e.ToString())
        None
  
  
  