measurePrompt :: IO Int
measurePrompt = loop
      where loop = do putStrLn "Which Domain ID is the Measurer?"
                      input <- getLine
                      case reads input of
                        [(id,_)] -> return id
                        _     -> do putStrLn "Error: Please Enter a Number."
                                    loop
measurePrompt :: IO Int
measurePrompt = loop
      where loop = do putStrLn "Which Domain ID is the Measurer?"
                      input <- getLine
                      case reads input of
                        [(id,_)] -> return id
                        _     -> do putStrLn "Error: Please Enter a Number."
                                    loop
measurePrompt = loop
      where loop = do putStrLn "Which Domain ID is the Measurer?"
                      input <- getLine
                      case reads input of
                        [(id,_)] -> return id
                        _     -> do putStrLn "Error: Please Enter a Number."
                                    loop