From: Jim Menard <jimm@...>
Date: 2001-05-15T10:10:04+09:00
Subject: [ruby-talk:15128] Re: initialize overload

Jim Freeze <jim@freeze.org> writes:

> Ok, the synapsis aren't firing so well today.
> How do I overload a constructor to get the effect:
> 
> m1 = Myclass.new(some_object)
> m2 = Myclass.new("text", "number")
> 
> I cannot do:
> 
> class Myclass
>  def initialize(o)
>     # use o
>  end
>  def initiaize(type, level)
>     # use type and level
>  end
> end
> 
> 
> Do I have to do something like:
> 
> class Myclass
>  def initialize(a, b=nil)
>    if Type == a.type
>      #do this
>    else
>      #do that
>    end
>  end
> end

Yes. Alternately, you can create class methods that create objects that are
named, for example, Myclass.newFromObject(some_object) and
Myclass.newFromText("text", "number"). I believe this is an example of the
Factory pattern.

Jim
-- 
Jim Menard, jimm@io.com, http://www.io.com/~jimm/
"Dvorak users of the world flgkd!" -- Kirsten Chevalier in rec.humor.oracle.d