Explanation of list reference

[Steven D'Aprano]

On Sat, 15 Feb 2014 23:01:53 +0200, Marko Rauhamaa wrote:

> Steven D'Aprano <steve+comp.lang.python at pearwood.info>:
> 
>> On Sat, 15 Feb 2014 18:29:59 +0200, Marko Rauhamaa wrote:
>>> Nowhere do I see the violating "x is y".
>>
>> Do you truly think that there is even the tiniest, most microscopic
>> chance that the int 230000 which has been garbage-collected and no
>> longer exists, and the int 420000, are the same object?
> 
> What were we talking about again?

Two distinct objects with the same id(). I demonstrated a situation where 
your claim:

    id(x) == id(y) implies x is y


fails. I explained *twice* how to rescue your claim. In each case you 
deleted my explanation, apparently unread. I can only conclude that you 
are not actually engaging in this discussion in good faith.

For anyone else reading, id(x) == id(y) implies that x is y only if x and 
y exist at the same time, in the same process. Python can re-use IDs, and 
you cannot compare IDs from multiple processes.



-- 
Steven