require 'date'
require 'time'

class Time
  def to_s(format = :default)
    case DATE_FORMATS[format]
    when Proc   then DATE_FORMATS[format].call(self)
    when String then strftime(DATE_FORMATS[format]).strip
    else to_default_s
    end
  end
end


  #
  # Custom time formats
  #
  # >> time.to_s(:stamp)
  # => 5:23PM
  #
  # >> time.to_s(:short)
  # => Dec 3, 2006
  #
  # >> time.to_s(:relative)
  # => today
  #
  Time::DATE_FORMATS[:stamp] = '%l:%M%p'
  Time::DATE_FORMATS[:short] = '%b %e, %Y'
  Time::DATE_FORMATS[:relative] = Proc.new do |date|
     date = Date.parse(date.to_s, true)
     days = (date - Date.today).to_i

     case true
     when days >= 0 && days < 1  then 'today'
     when days >= 1 && days < 2  then 'tomorrow'
     when days >= -1 && days < 0 then 'yesterday'
     when days.abs < 7           then "last " << date.strftime('%A').downcase
     when days.abs < 182         then date.strftime('%A, %B %e')
     else date.strftime('%A, %B %e, %Y')
     end
  end