From: Mark Hubbart <discordantus@...>
Date: 2005-05-11T00:17:50+09:00
Subject: Re: Enumerating only months in a Date range?

On 5/10/05, John Lam <drjflam@gmail.com> wrote:
> Is there a straight-forward way to list all of the months in a Date
> range? If I construct a date range, the each method iterates by day
> only.

There isn't a built-in way (that I know of), but it's pretty simple to
subclass date to make it work:

  class MonthlyDate < Date
    def succ
      self >> 1
    end
  end
  
  class Date
    def to_monthly 
      m = MonthlyDate.new
      instance_variables.map do |var|
        m.instance_variable_set( var,instance_variable_get( var ) )
      end
      m
    end
  end

Then convert your Dates to MonthlyDates (using #to_monthly) before
creating your range. The range will now skip months rather than days.

HTH,
Mark