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From: Eli Zaretskii <eliz@gnu.org>
To: LdBeth <andpuke@foxmail.com>
Cc: tom@logand.com, emacs-devel@gnu.org
Subject: Re: using finalizers
Date: Fri, 31 Dec 2021 09:50:41 +0200	[thread overview]
Message-ID: <83r19tgqlq.fsf@gnu.org> (raw)
In-Reply-To: <tencent_F418F83A1356647F356E00DD688E9F3D2608@qq.com> (message from LdBeth on Fri, 31 Dec 2021 10:46:20 +0800)

> Date: Fri, 31 Dec 2021 10:46:20 +0800
> From: LdBeth <andpuke@foxmail.com>
> Cc: emacs-devel@gnu.org
> 
> > What is the expected example usage of finalizers in Emacs Lisp?
> > How can I verify, that my finalizer works?
> 
> (setq bar nil)
> (setq foo (make-finalizer (lambda ()
>                             (setq bar t))))
> 
> (setq foo nil)
> (garbage-collect)
> 
> bar ; => t

I think that the assumption that a call to garbage-collect will
necessarily call the finalizer is also problematic: there's usually no
simple way to make sure there are no references left to the object,
and GC could have its own ideas when to actually garbage-collect an
object.



  parent reply	other threads:[~2021-12-31  7:50 UTC|newest]

Thread overview: 42+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-12-30 22:43 using finalizers Tomas Hlavaty
2021-12-31  2:46 ` LdBeth
2021-12-31  3:29   ` Stefan Monnier
2021-12-31  3:36     ` Stefan Monnier
2021-12-31  4:30     ` LdBeth
2021-12-31  4:43       ` LdBeth
2021-12-31  6:28   ` Tomas Hlavaty
2021-12-31 10:59     ` LdBeth
2021-12-31 11:18       ` Tomas Hlavaty
2021-12-31 11:41         ` LdBeth
2021-12-31 12:01           ` Tomas Hlavaty
2022-01-01 17:00     ` Stefan Monnier
2022-01-01 20:25       ` Tomas Hlavaty
2022-01-01 20:47         ` Stefan Monnier
2022-01-01 22:55           ` Tomas Hlavaty
2022-01-01 23:18             ` Stefan Monnier
2022-01-01 23:47               ` Tomas Hlavaty
2022-01-01 23:26             ` Tomas Hlavaty
2021-12-31  7:50   ` Eli Zaretskii [this message]
2021-12-31  9:31     ` Tomas Hlavaty
2021-12-31 12:27       ` Eli Zaretskii
2022-01-01 17:58         ` Tomas Hlavaty
2022-01-01 18:20           ` Eli Zaretskii
2022-01-01 20:55             ` Stefan Monnier
2022-01-01 23:05               ` Tomas Hlavaty
2022-01-01 23:21                 ` Stefan Monnier
2021-12-31 14:23       ` Rudolf Schlatte
2021-12-31 16:21         ` Stefan Monnier
2022-01-01 17:37           ` Tomas Hlavaty
2022-01-01 22:36         ` Tomas Hlavaty
2022-01-02  6:54           ` Eli Zaretskii
2022-01-02  7:53             ` Tomas Hlavaty
2022-01-02  8:33               ` Eli Zaretskii
2022-01-02 13:10                 ` Tomas Hlavaty
2022-01-02 14:42                   ` Eli Zaretskii
2022-01-02 15:16                     ` Eli Zaretskii
2022-01-02 17:18                       ` Tomas Hlavaty
2022-01-02 18:11           ` Rudolf Schlatte
2022-01-03  0:37             ` Tomas Hlavaty
2022-01-04  3:08               ` Richard Stallman
2021-12-31 14:39 ` LdBeth
2022-01-01 17:59   ` Tomas Hlavaty

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