From: Robert Klemme <shortcutter@...>
Date: 2011-01-18T18:36:08+09:00
Subject: Re: initialize() in a module, is it correct?

On Mon, Jan 17, 2011 at 7:32 PM, Iñaki Baz Castillo <ibc@aliax.net> wrote:
> El día 17 de enero de 2011 19:08, Jesús Gabriel y Galán
> <jgabrielygalan@gmail.com> escribió:
>>> However I would like to know if there could be an issue by using it.
>>
>> I don't think so. initialize it's just an instance method, just like
>> any other, with the same lookup path:
>>
>> irb(main):001:0> module M
>> irb(main):002:1> def test; puts "test from M"; end
>> irb(main):003:1> end
>> => nil
>> irb(main):015:0> class A
>> irb(main):016:1> include M
>> irb(main):017:1> def test; puts "test from A"; super; end
>> irb(main):018:1> end
>> => nil
>> irb(main):019:0> A.new.test
>> test from A
>> test from M
>
> This is what I expected (and hoped) :)
>
> Thanks a lot.

But you should change the signature to make it more compatible with
arbitrary inheritance chains:

module M
 def initialize(*a,&b)
   super
   puts "I'm module M"
 end
end

Now you can use this in different inheritance chains:

class X
  def initialize
    puts "X"
  end
end

class Y < X
  include M

  def initialize
    super
    puts "Y"
  end
end

class A
  def initialize(x)
    printf "A(%p)\n", x
  end
end

class B < A
  include M

  def initialize(a, b)
    super(a)
    printf "A(%p,%p)\n", a, b
  end
end

B.new 1,2
Y.new

Kind regards

robert

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