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From: "Mattias Engdegård" <mattias.engdegard@gmail.com>
To: Eli Zaretskii <eliz@gnu.org>
Cc: 63807@debbugs.gnu.org
Subject: bug#63807: bug in compose-gstring-for-terminal?
Date: Wed, 31 May 2023 17:08:58 +0200	[thread overview]
Message-ID: <C47A2E91-D33A-4B27-AC3A-DE0F5832736C@gmail.com> (raw)
In-Reply-To: <83sfbcefpa.fsf@gnu.org>

31 maj 2023 kl. 16.30 skrev Eli Zaretskii <eliz@gnu.org>:

> If we agree that replacing (+ 2) with (+ i 2) is "completely safe",
> then we basically agree that this code runs only when i == zero,
> right?

Yes -- that is, if we trust external invariants to enforce that it indeed only runs when i is 0. Otherwise, the current code is incorrect and changing it would fix a bug. Either way, changing it should do no harm and has the possibility of improving correctness.

I was unable to provoke that particular code to run for strings longer than 1 chars but that could just be my own ineptitude, and in any case it seems unsafe to rely on it. Maybe you could come up with an example?

(And to answer your question that I edited out in haste: there are no plans to warn about unary applications of `+`. This was just something I stumbled upon while researching something else.)






  reply	other threads:[~2023-05-31 15:08 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-05-30 20:36 bug#63807: bug in compose-gstring-for-terminal? Mattias Engdegård
2023-05-31 13:02 ` Eli Zaretskii
2023-05-31 13:49   ` Mattias Engdegård
2023-05-31 14:30     ` Eli Zaretskii
2023-05-31 15:08       ` Mattias Engdegård [this message]
2023-05-31 16:15         ` Eli Zaretskii
2023-05-31 17:23           ` Mattias Engdegård

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