[tex-eplain] Warnings about redefinition of xref labels

[Oleg Katsitadze]

On Mon, Apr 10, 2006 at 12:13:15PM -0400, Dorai Sitaram wrote:
> And I trust you (Oleg) are feeling better.

I do, thanks!

> Specifically, \href{#somelabel}{link-text} (note the #) makes link-text a
> hyperlink to wherever \label{somelabel} was placed in the current document.

If this is so then I doubt we should use the name `\href',
unless we implement the same functionality in Eplain.  But
this shouldn't be too difficult, so I think I'll be able to
do it.

OK, so we would have our own \href.  But do we need \label?
All we can do is this really trivial definition

  \def\label{\hldest{}{}}% \hldest will read the label parameter.

(this uses default type and option defaults), and let the
user redefine it to suit their needs.  If we decide to have
it, somehow I don't really like the name `\label' -- it's
too vague, not indicating the command's specific use for the
hyperlinks.  What about `\hllabel' or even `\hlabel' (by
analogy with `\href')?

Another proposal.  hyperref.sty has \hyperbaseurl{URL} which
defines a prefix for all URL links.  I think we also can
make use of this.  Internally, we will prepend it to every
URL, but we'll define it empty by default -- this will make
URL stuff backward-compatible.  But again maybe we should
change the name to something like `\hlbaseurl'?  We don't
have any `\hyper...' names, so it will really stand out.

> I don't know what the several labels in eplain translate to in terms of
> hyperlink anchor names in the PDF output (i.e., the PDF equivalent of <a
> name="...">).

Label names (including cross-reference labels for the
implicit hyperlinks) are used for PDF anchor names without
any mangling.

> I take it that eplain massages the label name somewhat differently
> depending on what category it is in, as it seems possible to have the same
> user-supplied label for various label categories.

Did this work for you?!  I'd be really surprised, because
the second definition of the label just overwrites the
previous one.  What's more, the next version of Eplain will
give warnings about the redefinitions (it's in CVS already).

Thanks for the info and suggestions,
Oleg