I'm very happy to see this book come on-line. Its parsing chapter is the best basic introduction to parsing for someone coming from the Perl milieu. Mark's presentation of memoization is the best I've seen. The writing itself can be taken as a model, and I mean both the Perl and the technical English. Etc., etc.

As long as the Perl community is producing books like this, Perl is not dying.

Many thanks, Mark