Occurrence DSL

A quick sketch of an idea for a flexible recurring events DSL.

Requirements

Code relies on ActiveSupport date extensions from Rails.

Examples

In irb:

require 'active_support/core_ext'
require 'lib/occurrence'

Occurrence.every.friday.each(Date.today, 10) {|d| p d }
# Fri, 25 Feb 2011
# Fri, 04 Mar 2011
# Fri, 11 Mar 2011
# Fri, 18 Mar 2011
# Fri, 25 Mar 2011
# Fri, 01 Apr 2011
# Fri, 08 Apr 2011
# Fri, 15 Apr 2011
# Fri, 22 Apr 2011
# Fri, 29 Apr 2011

Occurrence.every.friday.last_in_month.each(Date.today, 10) {|d| p d }
# Fri, 25 Feb 2011
# Fri, 25 Mar 2011
# Fri, 29 Apr 2011
# Fri, 27 May 2011
# Fri, 24 Jun 2011
# Fri, 29 Jul 2011
# Fri, 26 Aug 2011
# Fri, 30 Sep 2011
# Fri, 28 Oct 2011
# Fri, 25 Nov 2011

(Occurrence.every.friday.last_in_month | Occurrence.every.wednesday).each(Date.today, 15) {|d| p d }
# Wed, 23 Feb 2011
# Fri, 25 Feb 2011
# Wed, 02 Mar 2011
# Wed, 09 Mar 2011
# Wed, 16 Mar 2011
# Wed, 23 Mar 2011
# Fri, 25 Mar 2011
# Wed, 30 Mar 2011
# Wed, 06 Apr 2011
# Wed, 13 Apr 2011
# Wed, 20 Apr 2011
# Wed, 27 Apr 2011
# Fri, 29 Apr 2011
# Wed, 04 May 2011
# Wed, 11 May 2011