[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: substitute-in-file-name and "$"
From: |
Michael Albinus |
Subject: |
Re: substitute-in-file-name and "$" |
Date: |
Sun, 06 Jul 2003 01:16:44 +0200 |
User-agent: |
Gnus/5.1002 (Gnus v5.10.2) Emacs/20.7 (hpux) |
Luc Teirlinck <address@hidden> writes:
> Michael Albinus wrote:
>
> There is no rule that substitute-in-file-name must be called only
> once.
>
> Even if this rule is not stated explicitly, this just seems to be
> common sense. It would appear that this is just a special case of the
> general rule that one should avoid bugs.
At least the examples in the Elisp manual give the feeling that
substitute-in-file-name could be called without special attention. The
trap with the "$" char isn't obvious.
> For example, if you use partial-completion-mode, the filename in
> the minibuffer will be passed through substitute-in-file-name by
> PC-do-completion. Later file name operations which call internally
> substitute-in-file-name will fail therefore.
>
> To me, it would seem obvious that this is a bug in `PC-do-completion'.
> It can not handle filenames containing a literal `$'.
It takes any file name you offer. But at least it should perform a
special handling for "$" (requoting), as Stefan mentioned already in
the original thread in gnu.emacs.help.
> You say "for example". Are you aware of tons of similar bugs
> throughout the Emacs code or is `PC-do-completion' an isolated
> example?
At least I've done the same bug in tramp-smb.el (corrected). No, for
the time being that's the only case I know. But I fear that there are
other cases, because occasionally I get such reports for tramp-smb I
couldn't catch the origin. I'll investigate harder.
> What I'ld like to know: Is it a general rule, that
> substitute-in-file-name can be called only once for a given file name?
> Then it should be documented in the Elisp manual, and it is a bug in
> PC-do-completion. Or is it a more general design problem?
>
> It might actually be good to mention this potential trap in the Elisp
> manual. However, this is a matter of avoiding bugs, not a matter of
> following some stylistic "rule".
Not only a stylistic "rule" but a design constraint. So it is worth a
note in the manual.
And, btw, if substitute-in-file-name can be called only once, how do I
know it where to perform this call? And what shall the others do, if
they would like to perform substitute-in-file-name? Requote "$"? Or
apply an optional parameter (to be introduced), which forces this?
> Sincerely,
>
> Luc.
Best regards, Michael.