Re: ifinfo vs ifnottex

[Luc Teirlinck]

This concerns some @ifinfo-> @ifnottex changes I proposed.  Richard
has already asked me to install these changes, but I will wait till
this remaining issue is resolved.

I have the impression that my changes are clearly the right thing for
info and HTML and, as one should be able to use XML to read and
display .info files, most of what is right for info should be right
for XML as well.  _If_ one should also be able to use docbook to read
.info files, then I believe that this pretty much settles the issue,
by the same argument as for XML.

I have the impression that after my changes, the docbook output will
be in acceptable form.  If this is good enough, then this settles the
issue, as treating docbook separately will make things more complex.
If we want the docbook output to look as perfect as possible, assuming
that it should look more like Tex than like any of the other outputs,
then not only my changes, but all other occurrences of @tex vs
@ifnottex in the Emacs and Elisp manual might have to be reconsidered.
(That is a _lot_ more occurrences than just my proposed changes and
hence quite some work.)  If we want the plain text output to look as
close as possible to perfect too, rather than just acceptable, even
more complexity and changes are needed.

There are essentially five types of situations in my patches where
this question arises, all listed below, *but* there are _many_
additional types of situations, some more complex, in other places.

1.  The "@unnumberedsec" and "@heading" vs "@center" issue in the GPL
   doc.  (See my patches to gpl.texi.)  Richard has already asked me to
   install this, but I will wait to allow for counterarguments concerning
   docbook.  The current @iftex vs @ifinfo is clearly wrong as _nothing_
   gets output in any other format except plain text.

2.  One single instance where my changes might not be really the best
    thing for plain text (but does that matter a lot?) and maybe not
    for docbook:

  If you are going to write actual Emacs Lisp programs that go beyond
minor customization, you should read the @cite{Emacs Lisp Reference Manual}.
@ifinfo
@xref{Top, Emacs Lisp, Emacs Lisp, elisp, the Emacs Lisp Reference
Manual}.
@end ifinfo

3.  Situations like:

@ifinfo
(@pxref{Tab Stops}),
@end ifinfo
@iftex
(see next section),
@end iftex

Again, we could try to be more perfect here for plain text and maybe
docbook by making them go with Tex.  Worth the trouble?

4. Situations like:

  This section describes the commands to check the spelling of a single
word or of a portion of a buffer.  These commands work with the spelling
checker programs Aspell and Ispell, which are not part of Emacs.
@ifinfo
@xref{Top, Aspell,, aspell, The Aspell Manual}.
@end ifinfo

I guess the @ifinfo is there to save place in the _published_ Emacs
manual.  The reference is appropriate for plain text and docbook.

5.  Situations like:

@iftex
mode (@pxref{TeX Mode}).
@end iftex
@ifinfo
mode.
@end ifinfo

I do not understand this one and similar ones at all.  Why is there a
reference in the one situation where space is at a premium and none in
all other situations?  (This would remain true even after my changes.
But after my changes "mode." will no longer be missing in many
formats.)

Sincerely,

Luc.