I just love Date::Simple. It does exactly what it advertises to do: date calculations without any time component. It does it reliably, and with a very simple and intuitive interface.
I've never benchmarked it, so I can't comment on speed, but it was never the bottleneck of my applications, so it's reasonably fast :-)
A good idea to have a very light-weight and quite fast date module that supports so many rich features (arithmetic, various formats).
One niggle: dates can be made from 2005-12-06, but not 2005-12-6. It'd be nice if it did indeed produce a Date object, but I'd settle for a warning... It's only a niggle, but I write it here because I use this module in almost every project.
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