Look in the archives for weak references and finalization.

On finalization a shadow copy of your object is sent a finalization  
method after the real object has been GCed.
Other smalltalks provide a number of solutions up to including  
sending a message to your object saying it's going to be GCed
and asking if it should be resurrected. (not a squeak solution).

Normally this logic is used to close system resources, say operating  
system file handles.

see
StandardFileStream>>actAsExecutor
 >>finalize

StandardFileStream class>>register:
unregister:
registry

for clues.

On 1-Jun-06, at 12:26 PM, Bruno Luca wrote:

> Hello,
> i was looking at various method and classes but i didn't find  
> anything interesting about this question.
> Is there a way to catch GC when deleting an object? Something like  
> a method calling before deleting it...
>
> Byte.
>
> -- 
> www.lethalman.net - Thoughts about computer technologies
>

--
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John M. McIntosh <johnmci at smalltalkconsulting.com> 1-800-477-2659
Corporate Smalltalk Consulting Ltd.  http://www.smalltalkconsulting.com
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