[XeTeX] fontspec limits

[Will Robertson]

Hi

It's been on my list of things to do (actually, I never wrote it down, 
but it's been in the back of my head) to see how many times I can run 
\fontspec before something goes wrong.

After being run for the first time, a fontspec command with constant 
arguments does little except choose the already defined font. The 
problem is that you can only call the \font command so many times 
before XeTeX bottoms out, and this is necessary in the current version 
of the package every time \fontspec is called. This minimal example 
fails somewhere near the end:

    \documentclass{article}
    \begin{document}
    \newcount\zfcount
    \loop\advance\zfcount by 1
    \fontspec{Hoefler Text}
    % \font\1="Hoefler Text" at 10pt\1 % this line instead also fails
    fontspec loop test \number\zfcount\par
    \ifnum\zfcount < 2000 \repeat
    \end{document}

I will try and think out a more robust interface for cases when you 
want to define a fontspec instance for repetitive tasks like section 
headings. Probably something like

    \definefontinstance[Lettercase=Upper]{Hoefler Text}{\headings}

and henceforth the command \headings will produce uppercase Hoefler 
Text without having to do anything.

Another heads up...

W