Re: Info enhancements

[Juri Linkov]

Luc Teirlinck <address@hidden> writes:
> I have not yet had the time to look at your patch in detail.  I just
> looked at one feature:
>
>    - use reference names to move point to the place within the current
>      node where reference name is defined.  For example, by following the
>      reference "*Note file-coding-system-alist: Default Coding Systems,"
>      Info finds a node with the name "Default Coding Systems" and moves
>      point to the line where reference name "file-coding-system-alist" is
>      defined.
>
> I applied your patch.  I replaced the @xref{Default Coding Systems}
> in nonascii.texi you are referring to by 
> @xref{Default Coding Systems, file-coding-system-alist}.
>
> Then I launch info, go to (elisp)Default Coding Systems and click on
> that reference.  It indeed carries me to the intended place.  But the
> header-line goes blank.  `u' sometimes, but not always makes the
> header-line go blank: C-h i m elisp RET m non- RET m text re RET u
> Blank header line.  In general, it seems pretty easy to get a blank
> header line.  This happens regardless of the value of
> Info-hide-note-references.

Yes, this is because `Info-fontify-node' was called twice on the same
node where header was already made invisible, so it was copied again
with invisibility property to a header line.  I will fix it by calling
code that re-fontifies only node references.

BTW, I just noticed that `Info-fontify-node' uses the function
`Info-escape-percent' which have very limited applicability.
It doubles all occurrences of only one particular character %.
Seems this function is a copy of `replace-regexp-in-string'
with a little modification.  I think it's too bad to have such
a limited function: it should be removed with making modifications
in the `replace-regexp-in-string'.  What do you think?

> As an other remark on the feature, it needs help from the .texi source
> file.  So either other Info readers will have to adapt to the feature,
> or the references in the .texi files will have to be written in such a
> way that they look reasonable even in Info readers that do not have your
> feature.  (These Info readers behave like the Emacs Info reader with
> Info-hide-note-references  set to nil.)  Maybe the latter is no
> problem, because "*Note file-coding-system-alist: Default Coding Systems."
> makes sense to me, even without your feature.

I just discovered that the stand-alone Info reader already provides
exactly the same feature.  It uses a reference name to move to correct
position within the selected Info node.  It's too surprising to see
a feature the stand-alone Info reader has, but Emacs Info reader hasn't!

-- 
http://www.jurta.org/emacs/