Thanks for the write-up. I've had to re-read a couple of bits, but that's how you learn :)

My switch use to date has almost entirely been about parsing commandline args - one of the two time I didn't do that was when my colleague talked about the code smell.

It's been interesting watching how new areas in programming just unfold potential in front of you as you learn. My bash scripts used to be relatively simple, serial things, then a mentor forced me to start using functions - and that was eye-opening. Things made more sense, and not least because I had to keep less 'state' in my head. You mention map and similar, and this is something I haven't really touched yet, but it sounds like it'll help some of the things I do (mostly ops scripts).

Thanks again for the write-up.