http://www.perlmonks.org?node_id=70299


in reply to days in a month

Try running a search:
index.pl?node=leap%20year%20time%20calculation

That yeilded How do I determine if a given year is a leap year? and Answer: Leap Year for the leap year question. There are also several other nodes there with similar questions and the ever popular Time modules from CPAN. That lead me to: Time::DaysInMonth.pm