[tex-live] Bug in syntax package

[Scott Pakin]

The syntax.sty package that ships with the 20051102 version of TeX Live has
a serious bug: Line 191 refers to a nonexistent \@foundunderscore macro
that gets triggered when an underscore is used in the right-hand side of a
rule.  (At least, that's how I encountered the problem.)  I have no idea
where this version of syntax.sty comes from.  The version on CTAN, which
doesn't have this \@foundunderscore bug, is dated 1996/05/17 and is version
1.07.  The TeX Live version is also dated 1996/05/17 but is version 1.9.
Here's a diff of the two versions:

<                 [1996/05/17 1.9 Syntax typesetting (MDW)]
---
 >                 [1996/05/17 1.07 Syntax typesetting (MDW)]
191c191
<       {\act_{\@foundunderscore}}%
---
 >       {\act_{\@uscore.}}%
252,255d251
< \let\gr at leftsq\[
< \let\gr at rightsq\]
< \def\[{\gr at leftsq}
< \def\]{\gr at rightsq}
281a278,279
 >   \let\gr at leftsq\[%
 >   \let\gr at rightsq\]%
459,464d456
<   \def\gr at leftsq{\begin{stack}\\}%
<   \def\gr at rightsq{\end{stack}}%
<   \def\({\begin{stack}}%
<   \def\){\end{stack}}%
<   \def\<{\begin{rep}}%
<   \def\>{\end{rep}}%

And here's a minimal example demonstrating the problem:

     \documentclass{article}
     \usepackage{syntax}

     \begin{document}

     \begin{grammar}
     <this_works> ::= <this_does_not>
     \end{grammar}

     \end{document}

-- Scott