What is the semantics meaning of 'object'?

[Rotwang]

On 25/06/2013 23:57, Chris Angelico wrote:
> On Wed, Jun 26, 2013 at 8:38 AM, Mark Janssen <dreamingforward at gmail.com> wrote:
>> Combining integers with sets I can make
>> a Rational class and have infinite-precision arithmetic, for example.
>
> Combining two integers lets you make a Rational. Python integers are
> already infinite-precision. Or are you actually talking of using
> "machine words" and sets as your fundamental? Also, you need an
> ordered set - is the set {5,3} greater or less than the set {2} when
> you interpret them as rationals? One must assume, I suppose, that any
> one-element set represents the integer 1, because any number divided
> by itself is 1. Is the first operand 3/5 or 5/3?

You could use Kuratowski ordered pairs:

http://en.wikipedia.org/wiki/Ordered_pair#Kuratowski_definition

Not that doing so would be sensible, of course. I don't know much about 
low-level data structures but it seems obvious that it's much easier to 
implement an ordered container type than an unordered set on a computer.