From: rlf <Ron.Foster@...>
Date: 2010-11-25T22:10:28+09:00
Subject: Re: date of 1 year ago

On Nov 25, 3:11 am, Stu <s...@rubyprogrammer.net> wrote:
> On Wed, Nov 24, 2010 at 10:05 PM, zuerrong <zuerr...@gmail.com> wrote:
> > 2010/11/25 Stu <s...@rubyprogrammer.net>:
>
> >>  def years
> >>    year = 365
>
> > Well, how do you know every year has exactly 365 days?
> > I don't think this is a standard method for date calc.
>
> I was just trying to get you to closer to the syntax of your gnu date
> program. As I mentioned Date has it's own leap year boolean object. Of
> course you can always program your own leap year algorithm with a
> couple modulo operations. This way year can return the extra day you
> get every four years.
>
> Good luck and happy hacking =)

Besides overriding the plus and minus operators to deal with days, the
Date class also employs the shift operators to deal with months. So
try:

Date.today << 12

It deals with the leap year issue as well.