Perl for Web Site Management

Chapter 5. Parsing Text Files

If you’ve been working through the examples in this book in order, congratulations. You’ve now built up enough of a Perl vocabulary to begin doing really useful work. The extended example covered in the next two chapters is your reward: we’re going to use Perl to build a potentially large collection of HTML pages from a set of structured text files. This chapter explains how to take the text files containing our source data and parse that data into its component pieces. The next chapter shows how to take that parsed data and use it to output a collection of HTML pages.

To keep things in perspective, we’re still using pretty simplistic Perl. Many advanced Perl features are covered later in the book that will let us do this particular job faster, with the resulting code being shorter and cleaner. Just because we’re still using baby talk, though, doesn’t mean that what we’re doing isn’t extremely powerful. It is.

My toddler son has been working hard over the last 18 months to pick up a useful subset of English. At the time of this writing he can express preferences for different foods (saying “cacka?” to ask for a cracker, for example), choose among different leisure options (“pah?” to go to the park), and so on. To point out that he’s not speaking in complete sentences or using a William F. Buckley vocabulary misses the point: he has made a huge leap from the nonverbal world he used to inhabit. In the same sense, the little bit of Perl you’ve picked ...