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From: Stefan Monnier <monnier@iro.umontreal.ca>
To: Jonas Bernoulli <jonas@bernoul.li>
Cc: Zhu Zihao <all_but_last@163.com>, emacs-devel@gnu.org
Subject: Re: Slot accessing issues in EIEIO
Date: Thu, 07 May 2020 22:09:58 -0400	[thread overview]
Message-ID: <jwvmu6jxjy7.fsf-monnier+emacs@gnu.org> (raw)
In-Reply-To: <87mu6jzwoi.fsf@bernoul.li> (Jonas Bernoulli's message of "Thu, 07 May 2020 15:44:45 +0200")

>> To better understand, I suggest that I'll throw some solutions so you
>> can shoot them down explaining why they're not applicable.
>> Would it work to use the `slot-missing` generic function?
> I think the above addresses that.  But I guess the questions becomes
> "Well, what about `slot-unbound' then?".

Here's another solution instead of the pair-of-objects solution:

For each slot, use two different slot names:
- one for the "virtual slot" corresponding to a data base column.
- one for the "real slot" that caches the value from the database.

So when `slot-value` accesses a virtual slot, you get to `slot-unbound`
which can then lookup (and fill if needed) the corresponding real slot
(whose name can presumably be obtained by adding or removing some
prefix/suffix).


        Stefan




  reply	other threads:[~2020-05-08  2:09 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-05-06  4:17 Slot accessing issues in EIEIO Zhu Zihao
2020-05-06 13:28 ` Stefan Monnier
2020-05-06 14:28   ` Zhu Zihao
2020-05-06 21:58     ` Stefan Monnier
2020-05-07  3:20       ` Zhu Zihao
2020-05-07  3:39         ` Stefan Monnier
2020-05-07  4:00           ` Zhu Zihao
2020-05-07  4:55             ` Zhu Zihao
2020-05-07 12:11             ` Stefan Monnier
2020-05-07 14:13               ` Jonas Bernoulli
2020-05-07 14:52                 ` Zhu Zihao
2020-05-07 14:52                 ` Stefan Monnier
2020-05-08  3:12                   ` Zhu Zihao
2020-05-08  3:48                     ` Stefan Monnier
2020-05-08  9:12                       ` Zhu Zihao
2020-05-08 15:09                         ` Stefan Monnier
2020-05-07 12:15             ` Stefan Monnier
2020-05-07 14:16               ` Jonas Bernoulli
2020-05-07 13:44       ` Jonas Bernoulli
2020-05-08  2:09         ` Stefan Monnier [this message]
2020-05-06 15:44   ` Jonas Bernoulli
2020-05-06 15:56     ` Stefan Monnier
2020-05-06 16:43       ` Jonas Bernoulli
2020-05-06 17:06         ` Eric Abrahamsen
2020-05-07 19:32         ` Daniel Colascione
2020-05-06 15:40 ` Jonas Bernoulli

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