irb(main):001:0> Time.now => 2012-08-10 16:30:31 +0900 irb(main):002:0> Time.now.change :year => 2019 => 2019-08-10 16:30:52 +0900 irb(main):003:0> 2.weeks.ago => Fri, 27 Jul 2012 07:31:42 UTC +00:00 irb(main):004:0> Date.today => Fri, 10 Aug 2012 irb(main):005:0> Time.now.advance(:years => 1, :months => 3) => 2013-11-10 16:33:16 +0900 irb(main):007:0> 1.seconds => 1 second irb(main):009:0> 1.hours => 3600 seconds irb(main):010:0> 1.month => 1 month irb(main):011:0> 1.year => 1 year irb(main):012:0> 2.weeks.since => Fri, 24 Aug 2012 07:43:24 UTC +00:00
