[luatex] [tex-live] Ignored italic correction with lua(la)tex format

[Ulrike Fischer]

Am Thu, 13 Oct 2011 11:49:02 +0200 schrieb Khaled Hosny:


>> I'm obviously not able to follow. Of which letters are you speaking?
>> My version of luatex-unicode-letters.tex doesn't contain a \catcode
>> setting in line 18 (there is the \begingroup-command). 
 
> Sorry, line 28.
 
>> Also why it is necessary to change the formats? Why can't the
>> problematic catcodes be changed in the document?
> 
> I don't know which cat code is problematic and which is not (there are
> so many characters used in math),

Well in this case it is obviously the catcode of U+1D443. 

(I too find it a bit suspect that the catcode is used to decide if a
font related feature (italic correction) should be used.) 

>> but I think just resetting the catcode
>> table inside math mode would be less invasive, in latex something like:
>> 
>> \everymath{\luatexcatcodetable\CatcodeTableLaTeX}

I find it a bit problematic to reset the catcode table completly in
math. While it is unprobable that someone would try to use U+1D443
in a command name in math, I think it is not improbable that in
future a greek will use a beta, or a french an "é", or a german an
"ü" in a command name. I think that an unicode engine like luatex
should not force its users to use only ascii-commands in math. 

If the catcode must be reset (that is if the engine can not handle
the problem better) it would be much better to set it only at the
end of the math:

\documentclass{article}
\usepackage{unicode-math}
\setmathfont{XITS Math}

\begin{document}

$P($

{\catcode`\^^^^^1d443=12 
$P($} 

\def\tüt{abc}

$ \tüt P(\luatexcatcodetable\CatcodeTableLaTeX$

\tüt

\everymath{\luatexcatcodetable\CatcodeTableLaTeX}
$ \tüt P($ %wrong
\end{document}



-- 
Ulrike Fischer