Ben Finney ben+python at
Wed Mar 5 07:26:25 CET 2014

Rustom Mody <rustompmody at> writes:

> I can say "'id' is just 'machine-id' is just address at some low
> level"

You could say that, but it's wrong. The only thing promised by “object
identity” is that each object has it, and that it is different from the
identity of every other object concurrently existing.

“Machine id” is not entailed within that at all.

> And before you bring it up, "Jython's id is not machine-id" is putting
> the cart before the horse.

You have a false idea of what Python's object identity means, and it has
warped your understanding of what implementations do.

> "Jython is an imitation of Cpython and does a good job but not quite as
> in the case of 'id'"

Wrong. Jython and CPython both adhere to the guarantees of object
identity. Both implementations follow the language reference, and
neither implementation does object identity better or worse than the

 \       “Science shows that belief in God is not only obsolete. It is |
  `\                        also incoherent.” —Victor J. Stenger, 2001 |
_o__)                                                                  |
Ben Finney

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