ActiveSupport、Date#to_datetime
>> require "rubygems" => true >> require "active_support" => true >> Date.new(2008,12,31).to_datetime => Wed, 31 Dec 2008 00:00:00 +0000 >> Date.new(2008,12,31).to_datetime.class => DateTime
>> require "rubygems" => true >> require "active_support" => true >> Date.new(2008,12,31).to_datetime => Wed, 31 Dec 2008 00:00:00 +0000 >> Date.new(2008,12,31).to_datetime.class => DateTime