From: "Jesús Gabriel y Galán" <jgabrielygalan@...>
Date: 2008-11-28T20:41:17+09:00
Subject: Re: Ruby's duck typing

On Fri, Nov 28, 2008 at 12:25 PM, stephan.zimmer
<stephan.zimmer@googlemail.com> wrote:

>> As Paul Graham stated, "In the message-passing model, methods are *of*
>> objects, while in the generic function model, they are specialized
>> *for* objects.
>
> It might be naive, but wouldn't it be possible to simulate a generic
> function by simply accessing the types of the parameters (using
> "is_a?") and then provide different function bodies for different
> parameters?

For this you can take a look at facets/overload, which allows things like:

class X
    def x
      "hello"
    end

    overload :x, Integer do |i|
      i
    end

    overload :x, String, String do |s1, s2|
      [s1, s2]
    end
  end

(taken from facet's doc: http://facets.rubyforge.org/doc/index.html)

Jesus.