Question

I trying to do a each on a Date interval with Rails 3.2.. something like this:

(1.months.ago.to_date..5.months.from_now.to_date).step(1.month).each do |date|  
    puts date.strftime('%m/%Y')  
end  

But, the step(1.month) does not work.. seems like it get the first month (ex: today is august, it will return jully) and does not iterate the other months..

Is there a way to do that?

Thanks

Answer 1

You are using Date as your iteration base, and 1.month translates (behind the scenes) into seconds I believe.

When you add to the Date object, it’s in days, thus:

Date.today + 1 would be tomorrow

Thus, in your example, you are trying to step 2592000 days.

What you probably want is something more like:

 (1.months.ago.to_date..5.months.from_now.to_date).step(30).each { |date| puts date.strftime('%m/%Y') }

If you are looking for the iterator to be smart enough to know how many days are in each month when you are “stepping” that’s not going to happen. You will need to roll that on your own.

You can intelligently iterate through months by using the >> operator, so:

date = Date.today
while date < 5.months.from_now.to_date do
     puts date.strftime('%m/%Y')
     date = date>>1
end