3

Why is line b) working, but not line d), if compiled the with lualatex?

In Line b) the r (U+0072) is followed by ̈ (U+0308). This compiles without errors.

In Line d) the r (U+0072) is followed by ̙ (U+0319). This produces (if % removed) the error “\textbar̙ … Undefined control sequence. …”

\documentclass{article}
\usepackage{fontspec}
\usepackage{dejavu-otf}
\begin{document}
a) r̙ r̈ \$̈ \$̙
b) \textbar̈
c) \textbar{}̙
d) % \textbar̙
\end{document}

This is LuaHBTeX, Version 1.12.0 (TeX Live 2020/Debian)
Improve this question
3
  • 2
    The exact error is that \textbar̙ is undefined. The U+0319 has the catcode of a letter, and so continues the command name, you get an error for the same reason why you would get an error from \textbarx: the command name simply isn't defined.
    – Ulrike Fischer
    Apr 9, 2021 at 8:14
  • @UlrikeFischer yes that's clear but what happened with the first one that is using r followed by U+0308 which is also catcode 11 but \show\textbar̈ shows \textbar with the diacritic following, as if it were catcode 12 ?
    – David Carlisle
    Apr 9, 2021 at 8:57
  • oh it is catcode 12, that seems... wrong?
    – David Carlisle
    Apr 9, 2021 at 9:00

1 Answer 1

Reset to default
4

This seems to be an issue with the dejavu-otf package unicode-math it is making the combining diaeresis catcode12 (punctuation) so it can not be part of a command name


\showthe\catcode"0308
\documentclass{article}
\usepackage{fontspec}
\showthe\catcode"0308
%\usepackage{dejavu-otf}
\showthe\catcode"0308
\begin{document}
\showthe\catcode"0308

a) r̙ r̈ \$̈ \$̙
b) \show\textbar̈
c) \textbar{}̙
d)  \show\textbar̙
\end{document}

adding \catcode"0308=11 would restore the usual behaviour.

This seems to be a feature of unicode-math (I'll raise it there)

\documentclass{article}

\RequirePackage{unicode-math}
\showthe\catcode"0308
\setmathfont{TeXGyreDejaVuMath-Regular}
\showthe\catcode"0308
\begin{document}

\end{document}

just setting the math font changes the catcode of a text diacritic which seems... unexpected

Improve this answer
1

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.