What are the best-practices for implementing a CLI tool in Perl?

Question

I am implementing a CLI tool using Perl. What are the best-practices we can follow here?

Answer 1

Some lessons I've learned:

1) Always use Getopt::Long

2) Provide help on usage via --help, ideally with examples of common scenarios. It helps people don't know or have forgotten how to use the tool. (I.e., you in six months).

3) Unless it's pretty obvious to the user as why, don't go for long period (>5s) without output to the user. Something like 'print "Row $row...\n" unless ($row % 1000)' goes a long way.

4) For long running operations, allow the user to recover if possible. It really sucks to get through 500k of a million, die, and start over again.

5) Separate the logic of what you're doing into modules and leave the actual .pl script as barebones as possible; parsing options, display help, invoking basic methods, etc. You're inevitably going to find something you want to reuse, and this makes it a heck of a lot easier.