Re: File type misclassification
Salut Stefan, la 21.03.2007 15:21 Stefan Monnier skribis: Daniel, do you remember why you put an entry (%![^V] . ps-mode) in magic-mode-alist? Did it just seem like a good idea or was there some particular (set of) circumstances you had bumped into that called for it? I don't remember, but I checked this: The way I read magic, a conforming document must start with %!PS, but a non confirming one only with %!. The -- maybe not so important -- exception is: # This would otherwise be recognized as PostScript - [EMAIL PROTECTED] 0string%!VMF SunClock's Vector Map Format data Btw. on SuSE 10.1 this magic entry is ignored by the file command, maybe because it comes too late in the file. Juanma == Juanma Barranquero [EMAIL PROTECTED] writes: On 3/21/07, Stefan Monnier [EMAIL PROTECTED] wrote: Who put this entry in magic-mode-alist, and why? It's there since the beginning, at least according to ViewCVS (files.el, revision 1.720) and lisp/ChangeLog.11: 2004-11-03 Daniel Pfeiffer [EMAIL PROTECTED] * files.el (xml-based-modes): Delete var. (magic-mode-alist): New more general var. (set-auto-mode): Use it. Juanma coralament / best Grötens / liebe Grüße / best regards / elkorajn salutojn Daniel Pfeiffer -- lerne / learn / apprends / lär dig / ucz sięEsperanto: http://lernu.net / http://ikurso.net ___ emacs-pretest-bug mailing list emacs-pretest-bug@gnu.org http://lists.gnu.org/mailman/listinfo/emacs-pretest-bug
Re: File type misclassification
do you remember why you put an entry (%![^V] . ps-mode) in magic-mode-alist? Did it just seem like a good idea or was there some particular (set of) circumstances you had bumped into that called for it? I don't remember, but I checked this: The way I read magic, a conforming document must start with %!PS, but a non confirming one only with %!. Thanks. I.e. you just thought it would be a good idea. The question we were discussing is what Emacs should do with it, so what the standard says is not really important (this is very different from what `file' should do). And since Emacs usually uses file-name extensions to determine the mode of a file, it's important to only use magic-mode-alist in those rare cases where it's really important in practice. Stefan ___ emacs-pretest-bug mailing list emacs-pretest-bug@gnu.org http://lists.gnu.org/mailman/listinfo/emacs-pretest-bug
Re: File type misclassification
Stefan Monnier [EMAIL PROTECTED] writes: Sigh. Seems like a magic string for the TeXshop TeX editor. But I think just ruling out [VT] is still asking for trouble. I think a bug report to the TeXshop is in order. Uh, you people are joking, right? Nope! It is not a bug in TeXshop if Emacs' magic-mode-alist goes out of control and calls everything PostScript. The %! thingy is not Emacs's invention. It's how postscript was specified. The only relevant standard I can find starts off with %!PS-Adobe. In contrast, %! is far too generic to be useful. It may be a heuristic for a PostScript interpreter to decide whether it is getting fed PostScript on stdin. But it does not sound like a useful heuristic for a text editor to decide whether a named file contains PostScript code or anything else. And for that reason `file greek-utf8.tex' agrees with Emacs. This said, I'd be happy to see the %! entry removed from magic-mode-alist, because I think magic-mode-alist should really be kept to its absolute strictest minimum. I don't think that %!PS has comparable potential to do accidental harm. Whether it does noticeable good is a different question altogether. However, dvips -i produces PostScript files where the extension is replaced by a serial number. Those will not be recognized as PostScript without magic number detection. %!PS is completely sufficient for that purpose, however. I think that little except hand-crafted PostScript would ever start with %! alone, and hand-crafted PostScript will have a proper file name. Even if one uses dvips -N (which disabled structured comments) the file starts with %!PS (but not EPSF; comments have been disabled) So I think that %!PS _does_ have some usefulness, and it is clearly not as overboard as %!. -- David Kastrup ___ emacs-pretest-bug mailing list emacs-pretest-bug@gnu.org http://lists.gnu.org/mailman/listinfo/emacs-pretest-bug
Re: File type misclassification
Juanma Barranquero [EMAIL PROTECTED] writes: On 3/21/07, Stefan Monnier [EMAIL PROTECTED] wrote: because I think magic-mode-alist should really be kept to its absolute strictest minimum. Certainly, it should only be used for file formats which are often found without a telling file extension. Alas, it seems like Postscript is one of those. Do you have an example for a Postscript file on your system that is neither identified by the magic string %!PS nor an appropriate extension? -- David Kastrup ___ emacs-pretest-bug mailing list emacs-pretest-bug@gnu.org http://lists.gnu.org/mailman/listinfo/emacs-pretest-bug
Re: File type misclassification
On 3/21/07, David Kastrup [EMAIL PROTECTED] wrote: Do you have an example for a Postscript file on your system that is neither identified by the magic string %!PS nor an appropriate extension? No. But I don't understand your question. I was agreeing with you (yeah, it happens sometimes). Juanma ___ emacs-pretest-bug mailing list emacs-pretest-bug@gnu.org http://lists.gnu.org/mailman/listinfo/emacs-pretest-bug
Re: File type misclassification
Juanma Barranquero [EMAIL PROTECTED] writes: On 3/21/07, David Kastrup [EMAIL PROTECTED] wrote: Do you have an example for a Postscript file on your system that is neither identified by the magic string %!PS nor an appropriate extension? No. But I don't understand your question. I was agreeing with you (yeah, it happens sometimes). Basically, we have three proposals (partly proposed by previously existing code): a) accept %! as magic PostScript override (previous behavior) b) accept %!PS as magic override (what I proposed and checked in) c) don't accept any magic postscript override When arguing against c), it is not clear whether you agree with a) being a sufficiently bad idea. I had one example file causing problems with option a), and I already gave examples for files requiring b) (those produced using dvips -i don't have an extension, but in all cases start with %!PS). My point of view is that b) nowadays appears like the most pragmatically useful option, judging from problematic cases I have seen. If people can live with that, I suggest we leave it at that. While there are arguments for the other choices, we had them mentioned (Stefan's argument that magic should be kept to a minimum certainly _is_ valid) and, I believe, considered. Repeating them will just waste time. If people feel that they have been weighed wrongly, the way to resolve this is not repeating arguments, but vote on the resolution. Anybody who feels that the current solution b) as checked in by myself is not the best solution? If so, I'd want to either hear new arguments or have a vote. Everything else seems like a waste of time. -- David Kastrup ___ emacs-pretest-bug mailing list emacs-pretest-bug@gnu.org http://lists.gnu.org/mailman/listinfo/emacs-pretest-bug
Re: File type misclassification
In contrast, %! is far too generic to be useful. It may be a heuristic for a PostScript interpreter to decide whether it is getting fed PostScript on stdin. But it does not sound like a useful heuristic for a text editor to decide whether a named file contains PostScript code or anything else. Complete agreement. But it still means that TeXshop should avoid the %! magic characters because they have a conflicting meaning in some contexts. I don't claim that TeXshop should change for the sake of Emacs: it should change because its choice is fundamentally wrong, whether that bites Emacs users or not is irrelevant. This said, I'd be happy to see the %! entry removed from magic-mode-alist, because I think magic-mode-alist should really be kept to its absolute strictest minimum. I don't think that %!PS has comparable potential to do accidental harm. Whether it does noticeable good is a different question altogether. Obviously using a stricter regexp is good in my book since it means that magic-mode-alist is used less often. However, dvips -i produces PostScript files where the extension is replaced by a serial number. Those will not be recognized as PostScript without magic number detection. %!PS is completely sufficient for that purpose, however. Well, I find the likelihood of someone trying to edit with Emacs the output of dvips -i sufficiently low that it doesn't justify in my eye the use of a magic-mode-alist entry for it. That's just an opinion. Maybe a better solution is to make dvips output file names of the form foo.NNN.ps rather than foo.ps.NNN. So I think that %!PS _does_ have some usefulness, and it is clearly not as overboard as %!. We agree that it's a step in the right direction. Stefan ___ emacs-pretest-bug mailing list emacs-pretest-bug@gnu.org http://lists.gnu.org/mailman/listinfo/emacs-pretest-bug
Re: File type misclassification
Daniel, do you remember why you put an entry (%![^V] . ps-mode) in magic-mode-alist? Did it just seem like a good idea or was there some particular (set of) circumstances you had bumped into that called for it? Stefan Juanma == Juanma Barranquero [EMAIL PROTECTED] writes: On 3/21/07, Stefan Monnier [EMAIL PROTECTED] wrote: Who put this entry in magic-mode-alist, and why? It's there since the beginning, at least according to ViewCVS (files.el, revision 1.720) and lisp/ChangeLog.11: 2004-11-03 Daniel Pfeiffer [EMAIL PROTECTED] * files.el (xml-based-modes): Delete var. (magic-mode-alist): New more general var. (set-auto-mode): Use it. Juanma ___ emacs-pretest-bug mailing list emacs-pretest-bug@gnu.org http://lists.gnu.org/mailman/listinfo/emacs-pretest-bug
Re: File type misclassification
David Kastrup [EMAIL PROTECTED] writes: a) accept %! as magic PostScript override (previous behavior) b) accept %!PS as magic override (what I proposed and checked in) c) don't accept any magic postscript override ... My point of view is that b) nowadays appears like the most pragmatically useful option, judging from problematic cases I have seen. I agree. (b) is the conservative change. % is a common enough comment character that I can see %! as being slightly risky, but %!PS is far less so. -Miles -- 1971 pickup truck; will trade for guns ___ emacs-pretest-bug mailing list emacs-pretest-bug@gnu.org http://lists.gnu.org/mailman/listinfo/emacs-pretest-bug
Re: File type misclassification
1) Restrict the magic for PostScript files to %!PS (%!PS . ps-mode) Do Postscript files normally start with `%!PS'? If so, that change is clearly correct. 2) Recognize the specific case of TEX (%![^VT] . ps-mode) In TeX, the % is a comment character. There is no reason for it to be followed by `!TEX'. Is there some convention about using %! to start a file which is being followed here? It looks like one is in use, but I have never heard of it. To take this out of magic-mode-alist, and leave recognition of Postscript to file names alone, might be a good change, but I am not sure of usage practices. ___ emacs-pretest-bug mailing list emacs-pretest-bug@gnu.org http://lists.gnu.org/mailman/listinfo/emacs-pretest-bug
