curiosity about the nature of identity (in python)

Grant Edwards grante at visi.com
Thu Jun 29 00:20:13 CEST 2006


On 2006-06-29, Bruno Desthuilliers <bdesth.quelquechose at free.quelquepart.fr> wrote:

> Now what about this:
>
>>>> id(600)
> 134745616
>>>> id(601)
> 134745616
>
> id of an object is unique *for the lifetime of this object*. Nothing 
> prevents it from being reused later.

Indeed.  Since in CPython, it's the address of a C language
data structure, if IDs didn't get re-used, then the virtual
memory size of any long-running Python program would grow
without bound. The working set would grow more slowly that the
total virtual size, but it would still be problematic.

-- 
Grant Edwards                   grante             Yow!  I'm GLAD I
                                  at               remembered to XEROX all
                               visi.com            my UNDERSHIRTS!!



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