Chapter 3: Module Design and Implementation

Chapter 3 - Module Design and Implementation
by?Sam Tregar?
Apress ? 2002
Companion Web Site

Overview

PROGRAMMING IS BOTH science and art. The last chapter equipped you with the science of modular programming in Perl—the syntax and behavior of modules. This chapter will present the other side—the art of designing and implementing modules.

Just by using modular programming you're ahead of the programming pack— the majority of working programmers spend their days desperately writing one-off scripts in a dialect of Perl akin to BASIC. That said, there are good modules and there are bad modules. This chapter will help you write modules that resemble the former more than the latter. I expect you to treat the advice given critically—the best design technique to use will depend on your aesthetics, and that's the last thing I want to dictate!

Ultimately, there's only one inviolate rule of software design: Do it. It's worth it. The satisfaction you gain from jumping into the fray with some impulse coding won't last when the first wave of bug reports and unexpected changes lands. I'll leave it to the management books to break out the charts and graphs; if you give it a try you'll soon convince yourself. Every moment of thought and planning you put into a project at the outset will be paid back in spades by the end. It's a rare task that's really so small that it's worth knocking off without consideration.