From: Hugh Sasse Staff Elec Eng <hgs@...>
Date: 2002-09-20T01:49:52+09:00
Subject: Re: subclassing Integer

On Fri, 20 Sep 2002, John Tromp wrote:

> I'm writing a state space search program where each state can be consisely
> described by an Integer. I need these states to have several new methods.
>
> I can either
  [...]
> class State < Integer
>   def initialize(n)
>     super(n)
>   end
> end
>
> a=State.new(5)  # -> undefined method `new' for State:Class (NameError)

Do you need to know the number when you create it?  I'm wondering
how far Object#id gets you -- i.e. that each object already "knows"
its own number.  I can't remember/find how to get back from the
number to the object though.
>
> The only reason I would try option 2) is that
> I expect to have 100s of millions of these States around,
> and like 3) it might save memory.

Using the ids should help here I think because they exist anyway.

        Hugh