fizzbuzz-with-alias-and-prepend.rb

module Fizz
  def call(target, max, state)
    if target % 3 == 0
      state << "fizz"
    end
    super
  end
end

module Buzz
  def call(target, max, state)
    if target % 5 == 0
      state << "buzz"
    end
    super
  end
end

module Printable
  def call(target, max, state)
    if state.empty?
      puts target
    else
      puts state.join
    end
    super(target, max)
  end
end

module Clearable
  def call(target, max)
    super(target, max, [])
  end
end

class FizzBuzz
  prepend Printable
  prepend Buzz
  prepend Fizz
  prepend Clearable

  alias_method :step, :call

  def call(target, max)
    if target != max
      step(target + 1, max)
    end
  end
end

FizzBuzz.new.call(1, 100)

Inheritance tree

Object
|
`-FizzBuzz
  |
  `-Printable
    |
    `-Buzz
      |
      `-Fizz
        |
        `--Clearable

State map

START
|
v
Clearable#call <-.
|                |
(super)          |
|                |
v                |
Fizz#call        |
|                |
(super)          |
|                |
v                |
Buzz#call        |
|                |
(super)          |
|                |
v                |
Printable#call   |
|                |
(super)          |
|        (aliased from #step)
v                |
FizzBuzz#call ---'
|
v
END