From: John Tromp <tromp@...>
Date: 2002-09-20T01:20:35+09:00
Subject: subclassing Integer

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
1) create a new class with an Integer attribute
or
2) try to subclass Integer
or
3) pass around Integers to methods of another class

Option 2) appears to be possible, but perhaps useless, as I cannot
seem to generate objects of the new type:

class State < Integer
  def initialize(n)
    super(n)
  end
end

a=State.new(5)  # -> undefined method `new' for State:Class (NameError)

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.

Does anyone know if option 1) will take more memory than option 3)
and if anything like option 2) can combine their advantages?

regards,

%!PS                       %  -John Tromp (http://www.cwi.nl/~tromp/)
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