From: Stefan Monnier <monnier@iro.umontreal.ca>
To: Eli Zaretskii <eliz@gnu.org>
Cc: emacs-devel@gnu.org
Subject: Re: emacsclient's option decoding code
Date: Sat, 01 Nov 2008 22:13:26 -0400 [thread overview]
Message-ID: <jwvmygi3mwl.fsf-monnier+emacs@gnu.org> (raw)
In-Reply-To: <u7i7nwnj5.fsf@gnu.org> (Eli Zaretskii's message of "Sat, 01 Nov 2008 16:04:14 +0200")
> Please take a look at this fragment of emacsclient.c, which deals with
> various combinations of command-line options:
> if (!current_frame && !tty && !display)
> display = egetenv ("DISPLAY");
> if (display && strlen (display) == 0)
> display = NULL;
> if (!tty && display)
> window_system = 1;
> else if (!current_frame)
> tty = 1;
> /* --no-wait implies --current-frame on ttys when there are file
> arguments or expressions given. */
> if (nowait && tty && argc - optind > 0)
> current_frame = 1;
> if (current_frame)
> {
> tty = 0;
> window_system = 0;
> }
> if (tty)
> window_system = 0;
> I find this code highly confusing to the degree of being
> unmaintainable. Look, for example, how it sets `tty' to zero or
> non-zero, and how this is interleaved with testing whether it is zero
> or non-zero, completely obfuscating the semantics of the code and the
> meaning of each variable.
> I think this should be rewritten, but since I cannot make heads or
> tails out of it, I cannot do that myself without risking to break the
> code. Please someone make this code speak to a programmer.
Yes, I've written my fair share of it, and I'm not proud of it.
If someone can make it more clear, that'd be welcome. A marginal
improvement is to add an `else' before the last `if'.
Basically, the first 2 `if's setup the `display' variable; the
subsequent 3 enable various options (window_system, tty, and
current_frame) implied by the context; and the last 2 choose one among
the 3 mutually-exclusive options `current_frame', `tty', and
`window_system'.
Stefan
next prev parent reply other threads:[~2008-11-02 2:13 UTC|newest]
Thread overview: 67+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-11-01 14:04 emacsclient's option decoding code Eli Zaretskii
2008-11-02 2:13 ` Stefan Monnier [this message]
2008-11-02 21:45 ` Chong Yidong
2008-11-02 22:00 ` Juanma Barranquero
2008-11-02 23:18 ` Chong Yidong
2008-11-03 0:50 ` Juanma Barranquero
2008-11-03 4:14 ` Eli Zaretskii
2008-11-03 12:12 ` Juanma Barranquero
2008-11-03 20:06 ` Eli Zaretskii
2008-11-03 20:19 ` Chong Yidong
2008-11-04 4:20 ` Eli Zaretskii
2008-11-04 16:40 ` Chong Yidong
2008-11-06 11:56 ` Juanma Barranquero
2008-11-03 21:26 ` Juanma Barranquero
2008-11-04 4:19 ` Eli Zaretskii
2008-11-06 12:08 ` Juanma Barranquero
2008-11-07 9:53 ` Eli Zaretskii
2008-11-07 11:42 ` Juanma Barranquero
2008-11-07 11:47 ` Juanma Barranquero
2008-11-07 14:36 ` Eli Zaretskii
2008-11-07 14:42 ` Juanma Barranquero
2008-11-10 18:22 ` Juanma Barranquero
2008-11-10 18:36 ` Chong Yidong
2008-11-10 23:33 ` Juanma Barranquero
2008-11-11 4:09 ` Eli Zaretskii
2008-11-11 4:14 ` Chong Yidong
2008-11-11 21:16 ` Eli Zaretskii
2008-11-11 9:39 ` Juanma Barranquero
2008-11-11 15:37 ` Juanma Barranquero
2008-11-11 21:24 ` Eli Zaretskii
2008-11-11 23:36 ` Juanma Barranquero
2008-11-12 4:22 ` Eli Zaretskii
2008-11-12 9:41 ` Juanma Barranquero
2008-11-12 19:14 ` Eli Zaretskii
2008-11-12 21:05 ` Juanma Barranquero
2008-11-13 4:12 ` Eli Zaretskii
2008-11-13 8:34 ` Juanma Barranquero
2008-11-12 19:37 ` Eli Zaretskii
2008-11-12 2:31 ` Stefan Monnier
2008-11-12 9:33 ` Juanma Barranquero
2008-11-12 15:56 ` Stefan Monnier
2008-11-12 16:37 ` Juanma Barranquero
2008-11-12 17:13 ` Stefan Monnier
2008-11-13 1:16 ` Lennart Borgman
2008-11-13 4:18 ` Eli Zaretskii
2008-11-13 9:00 ` Juanma Barranquero
2008-11-13 15:45 ` Dan Nicolaescu
2008-11-13 16:05 ` Juanma Barranquero
2008-11-13 16:05 ` Juanma Barranquero
2008-11-13 16:08 ` Dan Nicolaescu
2008-11-12 19:36 ` Eli Zaretskii
2008-11-12 20:56 ` Stefan Monnier
2008-11-13 4:10 ` Eli Zaretskii
2008-11-13 4:29 ` mail
2008-11-13 20:54 ` Eli Zaretskii
2008-11-13 21:27 ` mail
2008-11-13 22:30 ` Eli Zaretskii
2008-11-13 23:54 ` mail
2008-11-13 20:03 ` Juri Linkov
2008-11-13 20:40 ` mail
2008-11-13 21:08 ` Thorsten Bonow
2008-11-13 22:01 ` Thorsten Bonow
2008-11-15 2:58 ` Evil Boris
2008-11-07 14:35 ` Eli Zaretskii
2008-11-03 14:45 ` Juanma Barranquero
2008-11-03 19:59 ` Eli Zaretskii
2008-11-03 20:03 ` Eli Zaretskii
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