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From: tomas@tuxteam.de
To: Ihor Radchenko <yantar92@posteo.net>
Cc: emacs-devel@gnu.org
Subject: Re: Why have a #if .... #else .... #endif construct in Emacs Lisp, when we could make the existing code DTRT unchanged?
Date: Tue, 5 Sep 2023 08:28:15 +0200	[thread overview]
Message-ID: <ZPbKfyavxzGncaBr@tuxteam.de> (raw)
In-Reply-To: <878r9lw4h1.fsf@localhost>

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On Tue, Sep 05, 2023 at 05:53:30AM +0000, Ihor Radchenko wrote:
> <tomas@tuxteam.de> writes:
> 
> > I did offer one: checking for a version number is actually a placeholder
> > for the feature your code cares about. Better be up-front in the test
> > and let the reader know what your code's needs are.
> 
> Not always. Sometimes, version check is necessary to work around bugs
> that exist in older Emacs.

I think I said in my original post "almost always". All generalisations
suck ;-)

But even in your example's case I'd try to come up with a test which
discriminates between the behaviours.

Now this is engineering and everything is a tradeoff. Perhaps this test
is prohibitive, perhaps it can't be done at compile time and so on.

So I do agree with your "not always".

Cheers
-- 
t

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  reply	other threads:[~2023-09-05  6:28 UTC|newest]

Thread overview: 66+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-08-28 19:37 Why shouldn't we have a #if .... #else .... #endif construct in Emacs Lisp? Alan Mackenzie
2023-08-28 19:47 ` Ulrich Mueller
2023-08-28 20:06   ` Alan Mackenzie
2023-08-28 21:01     ` Ulrich Mueller
2023-08-28 21:46       ` Alan Mackenzie
2023-08-31  2:07         ` Richard Stallman
2023-08-31  7:50           ` Alan Mackenzie
2023-09-04  1:34             ` Richard Stallman
2023-09-04 10:50               ` Alan Mackenzie
2023-09-04 11:02                 ` tomas
2023-09-04 15:19                   ` Emanuel Berg
2023-09-04 18:57                     ` tomas
2023-09-06  0:58                   ` Richard Stallman
2023-09-06  0:58                 ` Richard Stallman
2023-09-06  7:28                   ` Andreas Schwab
2023-09-06  9:31                     ` Alan Mackenzie
2023-09-06  9:56                   ` Alan Mackenzie
2023-09-09  0:39                     ` Richard Stallman
2023-09-09 10:32                       ` Ihor Radchenko
2023-09-10  0:22                         ` Richard Stallman
2023-09-10  8:36                           ` Ihor Radchenko
2023-09-13 23:53                             ` Richard Stallman
2023-09-20 12:59                               ` Ihor Radchenko
2023-09-05  0:30           ` Why have a #if .... #else .... #endif construct in Emacs Lisp, when we could make the existing code DTRT unchanged? Richard Stallman
2023-09-05  0:41             ` Emanuel Berg
2023-09-08 17:54               ` Emanuel Berg
2023-09-05  4:37             ` tomas
2023-09-05  5:53               ` Ihor Radchenko
2023-09-05  6:28                 ` tomas [this message]
2023-09-05 11:06             ` Adam Porter
2023-09-05 11:26             ` Lynn Winebarger
2023-09-05 14:11             ` Alan Mackenzie
2023-09-08  1:01               ` Richard Stallman
2023-09-08  2:45                 ` Po Lu
2023-09-10  0:24                   ` Richard Stallman
2023-09-05  8:14         ` Why shouldn't we have a #if .... #else .... #endif construct in Emacs Lisp? Ulrich Mueller
2023-08-28 19:53 ` Emanuel Berg
2023-08-29  9:19   ` Alan Mackenzie
2023-08-29 10:36   ` João Távora
2023-08-29 11:09     ` Ihor Radchenko
2023-08-29 11:20       ` João Távora
2023-08-30 20:48         ` Sean Whitton
2023-08-30 20:59           ` João Távora
2023-09-02 23:12     ` Stefan Monnier via Emacs development discussions.
2023-09-03  0:18       ` Emanuel Berg
2023-09-03 12:27       ` João Távora
2023-08-29 12:54 ` Philip Kaludercic
2023-08-29 13:23   ` Alan Mackenzie
2023-09-02 23:09   ` Stefan Monnier via Emacs development discussions.
2023-08-29 16:28 ` LdBeth
2023-08-29 20:09 ` Stefan Kangas
2023-08-30 10:31   ` Alan Mackenzie
2023-08-30 17:36     ` Stefan Kangas
2023-08-30 18:03       ` Alan Mackenzie
2023-08-30 18:17         ` Stefan Kangas
2023-09-02 15:06           ` Alan Mackenzie
2023-09-02 15:17             ` Eli Zaretskii
2023-09-02 19:43               ` Alan Mackenzie
2023-09-03  4:42                 ` Eli Zaretskii
2023-09-03 10:48                   ` Alan Mackenzie
2023-09-03 11:02                     ` Eli Zaretskii
2023-09-03 13:24                       ` Alan Mackenzie
2023-09-02 19:20             ` Philip Kaludercic
2023-09-02 19:37               ` Stefan Kangas
2023-09-02 19:58               ` Alan Mackenzie
2023-09-04 11:12                 ` Lynn Winebarger

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