autoflush and 'DESTROY'

Chady has asked for the wisdom of the Perl Monks concerning the following question:

fellow monks, here's the set-up:

index.pl is running and at a time it will gather and eval the string:

$string = 'require ./scripts/eliza.pl';
eval "$string";
[download]

now at eliza.pl I have this:

$|++;

use Chatbot::Eliza;

## do something with eliza...
[download]

Now if I run this I get the following warning message:

[Sat Mar 16 21:44:55 2002] C:\Inetpub\wwwroot\index.pl: (in cleanup) C
+an't access `DESTROY' field in object of class Chatbot::Eliza : [Sat 
+Mar 16 21:44:55 2002] C:\Inetpub\wwwroot\index.pl: at ./scripts/eliza
+.pl line 34
[download]

the problem goes away if I remove the autoflush $|++ line. Can someone explain to me why is this happening?

He who asks will be a fool for five minutes, but he who doesn't ask will remain a fool for life.

Chady | http://chady.net/

Comment on autoflush and 'DESTROY' Select or Download Code

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Re: autoflush and 'DESTROY' by tachyon (Chancellor) on Mar 16, 2002 at 20:44 UTC
Add the line: `sub DESTROY {}` [download] to the Chatbot::Eliza code to fix the warning. For some background on DESTROY see Object scope and DESTROY From perlman:perltoot: Destruction happens automatically via Perl's garbage collection (GC) system, which is a quick but somewhat lazy reference-based GC system. To know what to call, Perl insists that the destructor be named DESTROY. Perl's notion of the right time to call a destructor is not well-defined currently, which is why your destructors should not rely on when they are called. Evidently autoflush is altering when DESTROY is called. I recall reading somewhere that you should include a DESTROY() method to avoid warnings like this but can't remember where for the life of me. cheers tachyon s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print	[reply] [d/l]
Re: Re: autoflush and 'DESTROY' by Juerd (Abbot) on Mar 16, 2002 at 21:00 UTC
to the Chatbot::Eliza code to fix the warning. You don't have to modify the module itself for this. Changing the module will bite you when upgrading it. `sub Chatbot::Eliza::DESTROY { }` [download] U28geW91IGNhbiBhbGwgcm90MTMgY W5kIHBhY2soKS4gQnV0IGRvIHlvdS ByZWNvZ25pc2UgQmFzZTY0IHdoZW4 geW91IHNlZSBpdD8gIC0tIEp1ZXJk	[reply] [d/l]
Re: Re: Re: autoflush and 'DESTROY' by tachyon (Chancellor) on Mar 16, 2002 at 21:10 UTC
Or perhaps the more obscure `*{Chatbot::Eliza::DESTROY} = sub {};` [download] Have you considered a job with M$ ? Patching the source of the problem and informing the author is better than working around the error IMHO cheers tachyon s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print	[reply] [d/l]
Re: Re: Re: Re: autoflush and 'DESTROY' by Juerd (Abbot) on Mar 16, 2002 at 21:29 UTC
Re: Re: Re: Re: Re: autoflush and 'DESTROY' by tachyon (Chancellor) on Mar 17, 2002 at 09:32 UTC
Module author response time by mirod (Canon) on Mar 17, 2002 at 07:14 UTC
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