[Dev-luatex] \ifincsname broken

9 Oct 2011

      Hello,

\ifincsname behaves different from pdfTeX:

\catcode`\{=1
\catcode`\}=2
\ifx\directlua\undefined
\else
  \directlua{tex.enableprimitives('',{'ifincsname'})}%
\fi
\def\empty{}
\edef\x{%
  \expandafter\noexpand\csname
    A\csname empty\endcsname\ifincsname A\else B\fi
  \endcsname
}
\immediate\write16{\meaning\x}
\csname @@end\endcsname\end

Result with pdfTeX 3.1415926-2.3-1.40.12 (TeX Live 2011): \AA
Result with LuaTeX beta-0.70.1-2011061416 (rev 4277):     \AB

It seems that in LuaTeX the true setting of \ifincsname
is cleared after the embedded \csname...\endcsname instead
of restoring the previous status of \ifincsname.

Yours sincerely
  Heiko Oberdiek