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Cyclops 0.9.4

Greg Ewing greg.ewing at compaq.com
Thu Jul 22 17:35:56 EDT 1999 
Tim Peters wrote:
> 
> You want to know about objects still living that you don't expect to be
> living.  No system can answer that for you!  They can't know what you expect
> <wink>.

I'm quite happy to go through the list of living objects
and decide for myself which ones should be dead. What I
meant was, what I really want to know is how those objects
got reached. If there are cycles involved, it wouldn't
hurt to be told about them, but they're not the most
important thing.

> If what you want is a list of all reachable objects,

No, I'd like a list of *all* objects, reachable or not.
Cyclops could then do what it does now, but for the
isolated islands of garbage as well.

> All of those are also needed if Python is ever to move toward builtin
> portable mark-&-sweep (optional or not).  The advantage over "walking an
> (explicit) list" is no overhead (time or space) unless & until it's used.

If there were mark & sweep there wouldn't be unreachable
garbage, so in that case you are right -- there would be
no point in keeping a list. I'm only suggesting it as an
interim measure.

> then a Cyclops-like thingy could tell you not only that
> something unexpected is still alive, but also from where it can be
> reached

I don't understand why Cyclops couldn't be made to do
that now. It reached those objects somehow -- all it needs
to do is remember how!

I don't mean to sound ungrateful for Cyclops, by the way --
it's a great idea. All it needs is a little bit more help
from the Python core to make it even greater...

With-government-funding-I'm-sure-I-could-make-it-*really*-silly-oops-er-I-mean-useful,
Greg
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