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To: Damien Doligez <Damien.Doligez@inria.fr>
Cc: caml-list@pauillac.inria.fr
Subject: Re: Weak pointers 
In-Reply-To: Damien.Doligez's message of Tue, 18 Mar 1997 15:34:54 +0100.
      <199703181434.PAA12806@tobago.inria.fr> 
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Date: Tue, 18 Mar 1997 15:51:46 +0000
From: Kohler Markus <kohlerm@betze.bbn.hp.com>
Sender: weis

> >The problem is that if you delete an element in the tree it may be that the 
> >hash table still points to the node, because there was no garbage collection 
> >yet. It could be possible that you would still find the entry trough the hash 
> >table.
> 
> I don't see a problem here.  You find the entry and use it instead of
> allocating a new node.  This is a rather good thing.  It means you
> avoid allocating, and leave less garbage for the GC to collect.
> 

But how do you know then that value is not valid anymore ?
I you use a flag to indicate that then I don't see an advantage of using a 
weak pointer. 
The same could be done with a "normal" pointer. 

Markus
  



 

-- 
+----------------------------------------------------------------------------+
| Markus Kohler                          Hewlett-Packard GmbH                |
| Software Engineer                      Network & System Management Division| 
|                                        IT/E Success Team                   |
+----------------------------------------------------------------------------+