[texhax] LaTeX hangs up with $(\ref{label})$ and [spanish]{babel}

[gabriele balducci]

> philip.ratcliffe at uninsubria.it ("Philip G. Ratcliffe") writes:
> [someone asked]
> >| I have experienced an annoying behaviour of LaTeX.  When I use a reference
> >| inside math mode
> >| the TeX program hungs up without any error message.  I have reproduced the
> >| problem in the small document below.
> >| This happens when using  \usepackage[spanish]{babel} and after using \chapter.
> 
> >I suspect it has to do with the way the "spanish" package redefines "."
> >although I haven't time to delve any deeper.
> 
> It is.
> 
> The \ref command temporarily sets \@safe at activestrue while it typesets
> the reference ("1.1").
> 
> The dot has a 8000 mathcode which makes it active within math mode.
> It is defined to be "\es at use@shorthand ." which, when \@safe at actives
> is true, expands to "\string .", which expands to just "." and so
> the loop starts again.
> 

If you don't care, you can request babel not to use `.' (dot) as a
shorthand with:

\shorthandoff{.}

somewhere after \begin{document}


Hope this helps

Ciao
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Gabriele Balducci                  tel    I-040-5583957
Dipartimento di Scienze Chimiche   fax    I-040-5583903
Via L. Giorgieri 1                 e-mail balducci at univ.trieste.it
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