Curious...

gistfile1.rb

#!env ruby

class Address

  attr_accessor :street1, :street2, :city, :state, :zip

  def initialize(attributes = {})
    attributes.each do |k,v|
      self.send(:"#{k}=", v)
    end
  end

end

module AddressDecorator

  def address
    "#{street1}\n" << if street2
      "#{street2}\n"
    else
     ''
    end << "#{city},#{state}\n#{zip}"
  end

  def street1
    titleize(super)
  end

  def street2
    titleize(super) if super
  end

  def state
    case super
    when 'MA'; 'Assachusetts'
    when 'NY'; 'Moo York'
    when 'RI'; raise 'Invalid loser'
    else; 'I don\'t know'
    end
  end

  private

  def titleize(s)
    s.split(/(\W)/).map(&:capitalize).join
  end
end

a = Address.new(:street1 => '123 Baker St.', :city => 'Omaha', :state => 'MA', :zip => '02561')

b = Address.new(:street1 => '123 Baker St.', :city => 'Omaha', :state => 'MA    ', :zip => '02561')

b.extend AddressDecorator

puts "#{b.address}"
puts "#{a.address}" if a.respond_to?(:address)