Error prevention
At this point, you should have a firm grasp on how we can handle (user input) error. Obviously, context is everything here: depending on the situation, some errors are handled in different ways. There is one more important subject in this chapter, and that is error prevention. While knowing how to handle errors is one thing, it would be even better if we can prevent errors during script execution altogether.
Checking arguments
As we noted in the previous chapter, when you're dealing with positional arguments passed to your script, a few things are very important. One of them is whitespace, which signifies the boundary between arguments. If we need to pass an argument to our script that contains whitespace, we need to wrap that argument in single or double quotes, otherwise it will be interpreted as multiple arguments. Another important aspect of positional arguments is getting exactly the right number of arguments: not too few, but definitely not too many either.
By starting...
