It seems normal enough that the version available for download of a CPAN module requires v 5.8 of Perl, whereas the production system will more likely be somewhere between 5.004 and 5.6.1. Maybe one day in the distant future that module may be compatible with these production systems but maybe the minimum for the version in CPAN will be 5.10 or 6.3 by then.
Setting aside the fact that most modules on CPAN take great pains to be backwards-compatible with at least 5.6.0 (or earlier!), you can always see every single upload to CPAN through use of the BackPAN. So, you can always get at the version you want to use today, but can't until next year.
As for version compatibility on CPAN ... I'm of two minds. In Excel::Template, I actually have an eval-block to determine if I can use 3-arg open or if I'm at a version that requires 2-arg open. In PDF::Template and PDF::Writer, I require 5.6.0 at a minimum. I don't depend on 5.6 features, but I feel that it helps stabilize my testing burden because I don't need to keep a bunch of different versions of Perl around. Now, if there was an easy way to have Test::More or Module::Build run a test suite against various versions of Perl and report errors by Perl version, I would change my tune. Or if there was documentation of how to tune your code to be more in tune with the version of Perl it's running under, then I'd have no problem. Older versions of PDF::Template actually have provisions for whether or not to use Unicode::String based on Perl version, but it uses PM_FILTER which is marked "DO NOT USE" in ExtUtils::MakeMaker and I haven't seen the way around it in Module::Build.
My criteria for good software:
- Does it work?
- Can someone else come in, make a change, and be reasonably certain no bugs were introduced?
