Usefulness, like beauty, is often in the eye of the beholder. If this isn't homework, I might guess that you saw something and said "why would anyone do that?" or else you are in a debate with someone about the value of (a) multiplicity or (b) genericity. Based on questions you have asked at Perl Monks so far I'm guessing that your question is in fact how to make a program for reading a very specific file more generally useful. But that is just a guess.

Perhaps you could tell us what raised this question for you and how an answer will help you?

Best, beth