ActiveSupport、String#to_datetime
>> require "rubygems" => true >> require "active_support" => true >> "2008-01-01".to_datetime => Tue, 01 Jan 2008 00:00:00 +0000 >> "2008-01-01".to_datetime.class => DateTime
>> require "rubygems" => true >> require "active_support" => true >> "2008-01-01".to_datetime => Tue, 01 Jan 2008 00:00:00 +0000 >> "2008-01-01".to_datetime.class => DateTime