#!/usr/bin/env ruby
# This code comes from http://ruby-it.org/pages/Creare+Enumerable
# Check the page for copyright notice and explanations



 enumerabile.each do |x|
  fai cose con x
 end

 >> class Tripla
 >>  def initialize(a,b,c)
 >>   @a,@b,@c=a,b,c
 >>  end
 >>  def each
 >>   yield @a
 >>   yield @b
 >>   yield @c
 >>  end
 >> end
 => nil

 >> t=Tripla.new 10, 20, 30
 => #<Tripla:0x27bd060 @b=20, @a=10, @c=30>
 >> t.each { |x| puts x }
 10
 20
 30
 => nil

 >> class Tripla
 >>  include Enumerable
 >> end
 => Tripla

 >> t=Tripla.new 17,42,11
 => #<Tripla:0x2753c30 @b=42, @a=17, @c=11>
 >> puts t.sort  # ordiniamoli
 11
 17
 42
 => nil
 >> puts t.map {|x| x*2} # raddoppiamo i valori
 34
 84
 22
 => nil
 >> puts t.select {|x| x%2==1} # selezioniamo i dispari
 17
 11
 => nil