Rails console での [Time, DateTime, Date] の localtime などの挙動メモ

(Rails.3.2.8, Ruby1.9.3)

irb(main):034:0> Time.now
#=> 2012-12-23 13:55:02 +0900
irb(main):035:0> Time.current
#=> Sun, 23 Dec 2012 04:55:06 UTC +00:00
irb(main):036:0> Time.current.localtime
#=> 2012-12-23 13:55:11 +0900
irb(main):037:0> DateTime.now
#=> Sun, 23 Dec 2012 13:55:28 +0900
irb(main):038:0> DateTime.current
#=> Sun, 23 Dec 2012 04:55:35 +0000
irb(main):039:0> DateTime.current.localtime
NoMethodError: undefined method 'localtime' for Sun, 23 Dec 2012 04:55:38 +0000:DateTime
irb(main):040:0> Date.now
NoMethodError: undefined method 'now' for Date:Class
irb(main):041:0> Date.today
#=> Sun, 23 Dec 2012
irb(main):042:0> Date.current
#=> Sun, 23 Dec 2012
irb(main):043:0> Date.current.localtime
NoMethodError: undefined method `localtime' for Sun, 23 Dec 2012:Date