# 99 bottles of beer, in Ruby
# illustrates inheritance, blocks/yield, class methods, arrays, iterators
# Kian Wright

class Song
	def Song.sing(fridge)
		sing_how_many(fridge, :on_the_wall)
		sing_how_many(fridge, :nowhere)
		yield
		sing_how_many(fridge, :on_the_wall)
		puts
	end
	
	def Song.sing_how_many(fridge, where=:on_the_wall)
		puts "#{fridge.to_s} of beer #{where == :on_the_wall ? 'on the wall' : ''}"
	end

end

class Beer
	def drink(from=nil)
		from.delete(self) if from && from.respond_to?(:delete)
		puts "ta