From: Eric Christopherson <echristopherson@...>
Date: 2012-02-06T10:00:20+09:00
Subject: Re: inheritance one more time

On Sun, Feb 5, 2012 at 4:48 PM, luk malcik <aport99@gmail.com> wrote:
> Hi, similar topic was here but still I can't do that. This is my code:
>
> Square = Struct.new(:x,:y,:a) do
>
>   include Domieszka
>
>   def pole
>
>   p = a**2
>
>   end
>
>   def obwod
>
>   o = 4*a
>
>   end
>
>   def pole=(a)
>
>   self.a = a
>
>   end
>
>   def obwod=(a)
>
>   self.a = a
>
>   end
>
> end
>
>
>
> class Rectangle<Square
>
>   include Domieszka
>
>   def pole=(b)
>
>   self.b = b
>   end
>   def pole
>   p=a*b
>
>   end
>
>
>
> Why there is no possibility to write :
> r = Rectangle.new
> r.pole = 3
> "Undefinied method error..."
>
> Domieszka is module declared at the beginning of my code, I dont put it
> here

I'm not sure what's in your Domieszka module, but in the code you
pasted, there are no methods b or b= in Rectangle; and there are no
methods a or a= in Square. The missing Rectangle#b= is why r.pole = 3
doesn't work.

Also, since you include Domieszka in the superclass, there's no need
to include it again in the subclass.