GNU bug report logs - #67669
29.1; Drop text suggesting using `and' to replace `if'

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Package: emacs;

Reported by: Xiyue Deng <manphiz <at> gmail.com>

Date: Wed, 6 Dec 2023 21:48:01 UTC

Severity: normal

Found in version 29.1

Done: Xiyue Deng <manphiz <at> gmail.com>

Bug is archived. No further changes may be made.

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From: Eli Zaretskii <eliz <at> gnu.org>
To: Xiyue Deng <manphiz <at> gmail.com>
Cc: 67669 <at> debbugs.gnu.org
Subject: bug#67669: 29.1; Drop text suggesting using `and' to replace `if'
Date: Thu, 07 Dec 2023 19:56:29 +0200
> From: Xiyue Deng <manphiz <at> gmail.com>
> Cc: 67669 <at> debbugs.gnu.org
> Date: Thu, 07 Dec 2023 09:49:13 -0800
> 
> Agreed on the point of being educational, and of course in the end
> coding style is mostly a matter of personal preference.  However, I
> would argue a bit that in such case we wouldn't need `if' or `when' at
> all as both can be emulated by `and' and `or' if you are careful enough.
> On the other hand, `if' and `when' should exist for a reason.  I quite
> like this suggestion[1] that `if' and `when' are used to guard side
> effects, whereas `and' and `or' are used for pure functions.
> Interestingly the current example you quoted changed from using `and'
> (as in the old version I quoted) to `if' probably based on this
> reasoning.  Similarly I wouldn't suggest to replace `if' with `and' in
> the original example around the text we are discussing:
> 
>   (if interprogram-cut-function
>       (funcall interprogram-cut-function string (not replace))))
> 
> as we are also guarding a side effect here.
> 
> Wdyt?

Sorry, I don't understand what you mean by "guarding a side effect",
and I'm not sure where this discussion goes.  If the issue is personal
stylistic preferences, then I'd prefer to leave the text as it was
according to the preferences of the original author (which I happen to
share, but that's not important).

OK?




This bug report was last modified 1 year and 224 days ago.

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