Range operators in Ruby similar to PostgreSQL

Question

Is there a Ruby gem that enables Range calculations similar to what PostgreSQL does? Especially the time-related range functions?

Answer 1

There's Range#cover? to test if an object is between the begin and end of the range.

Ruby's equivalent to '[2011-01-01,2011-03-01)'::tsrange @> '2011-01-10'::timestamp is:

(Date.new(2011,01,01)..Date.new(2011,03,01)).cover? Date.new(2011,01,10)
# => true

It tests Date.new(2011,01,01) <= Date.new(2011,01,10) <= Date.new(2011,03,01).

Answer 2

Without knowing exactly what you are trying to accomplish it's hard to answer this question, but you may want to check out the CoreExtensions module of the ActiveSupport gem: http://guides.rubyonrails.org/active_support_core_extensions.html

Install ActiveSupport with gem install activesupport or add it to your Gemfile.

With ActiveSupport you can do things like this:

require 'active_support/core_ext'

10.days.from_now #=> 2013-06-08 08:37:34 -0400
DateTime.now.beginning_of_year #=> Tue, 01 Jan 2013 00:00:00 -0400
1.megabyte #=> 1048576
(1..10).step(2) #=> [1, 3, 5, 7, 9]
(1..10).overlaps?(0..7) #=> true
Date.current.next_month #=> Sat, 29 Jun 2013
Date.current.prev_week(:friday) #=> Fri, 24 May 2013

I hope this helps.