# Error handling The previous example is a simple way to handle errors. - we'll learn a better way when we cover *exceptions* later in the course -- Some general rules about error handling: - If your code is making assumptions about its inputs, check them! - for example, if your code assumes a parameter is positive, check and alert the user if this is not the case (and exit if appropriate) - *this will save you time later on!* -- - If you can reasonably handle the error, do so, but warn the user about it -- - Most of the time, the error will be *fatal* (not recoverable), in which case your program should *not* proceed - issue an informative message about the problem, and exit with a non-zero exit code -- - try to detect errors as early as possible - for example: don't start a long batch of processing without first checking that you can create the output file