ruby 2.0 lazy

gistfile1.rb

require 'date'
def each_fridays
	friday = Date.new(2013,1,4)
	loop do
		yield friday
		friday += 7
	end
end
fridays = enum_for(:each_fridays)

# puts fridays.first 5
# fridays.select{|date| date.day == 13 }.first 5
puts fridays.lazy.select{|date| date.day == 13 }.first 5