From: Tomas Hlavaty <tom@logand.com>
To: LdBeth <andpuke@foxmail.com>
Cc: emacs-devel@gnu.org
Subject: Re: using finalizers
Date: Fri, 31 Dec 2021 07:28:40 +0100 [thread overview]
Message-ID: <875yr5p9t3.fsf@logand.com> (raw)
In-Reply-To: <tencent_F418F83A1356647F356E00DD688E9F3D2608@qq.com>
On Fri 31 Dec 2021 at 10:46, LdBeth <andpuke@foxmail.com> wrote:
>>>>>> In <878rw1pvcw.fsf@logand.com> Tomas Hlavaty <tom@logand.com> wrote:
> You are probably taking the wrong assumption about the effect of letrec
> So, `close' is nil and the lambda is never set as the finalizer.
You are right, the order was wrong.
>> 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
Nice, that works.
One more question: Because make-finalizer in Emacs Lisp does not take
the object into account, I have to make sure to hold the reference to
the finalizer somehow. However, this might not be trivial, because a
smart compiler could eliminate the reference. Is this not an issue?
Shouldn't make-finalizer take the object as an argument and not rely on
me holding the reference explicitly?
Thank you!
next prev parent reply other threads:[~2021-12-31 6:28 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 [this message]
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
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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