Sorry, gotta disagree on the idea that one doesn't parse large files often with Perl. At least in my experience it's been a huge part of what I do... I guess it really depends on the sort of jobs you do with Perl...

I see your point though... In many respects, it's not the file that really matters, it's the approach of setting up a datastream and then looping over it, whether it be a file, or socket, or database queries...

I think the exercise is fine, but when if he doesn't get it, I agree you've gotta back off and try a more basic approach. The nice thing about an exercise like this one is that it often teaches a lot of concepts at once, and can be extended... by simply tweaking it to add a new feature like Time::Local, or regex, or uniquifying hashes, etc...

--Ray