From: Peter Michaux <petermichaux@...>
Date: 2006-10-29T17:10:12+09:00
Subject: Re: Interesting trival example of why open classes are good?

> > I am trying to explain why the fact that Ruby's classes are never
> > closed is advantageous. I can only think of relatively complex examples
> > like Rails plugins. Does anyone have an interesting, standalone example
> > showing the utility of open classes in under 30 lines? under 20?
>
> That is way too easy.
>
> ---------------------------------
>
> #!/usr/bin/ruby -w
>
> class Fixnum
>   def odd?
>     return self & 1 == 1
>   end
> end
>
> 10.times do
>   puts rand(30).odd?
> end
>
> ---------------------------------
>
> There is no "odd?" function in Fixnum, but adding one is trivial.

Thanks for the example. I like it and I'll use it.

> Examples abound where this open-class business comes in handy.

Do you know of a nice little example that doesn't modify a built in
Ruby class? I didn't realize I wasn't specific enough in my request.

Thanks again,
Peter