B.2. Regular Expressions
Yes, there's more about regular expressions than we mentioned. Mastering Regular Expressions by Jeffrey Friedl (O'Reilly) is one of the best technical books we've ever read.[*] It's half about regular expressions in general, and half about Perl's regular expressions. It goes into detail about how the regular expression engine works internally and why one way of writing a pattern may be much more efficient than another. Anyone who is serious about Perl should read this book. See the perlre manpage (and its companion manpages perlretut and perlrequick in newer versions of Perl). And, there's more about regular expressions in the Alpaca as well.