[XeTeX] fontspec and sans-serif math fonts

[Patrick Dondl]

Hi,

I noticed that when using beamer in its standard font configuration,  
it would switch the math fonts to a sans-serif version (cmss). When  
using fontspec, though, they would always be reverted to the standard  
CM math font. Generally I found it a bit difficult to predict what  
fontspec would do to my maths font, i.e., when loading the 'euler'  
package, fontspec would change some of the math fonts back to CM,  
unless I used the 'cm-default' switch.

To get around the sans/con serif problem, I patched fontspec a bit to  
include a 'sans' option, which makes it choose the cmss math fonts  
instead. That's a bit crude, though, and I'm wondering if I  
overlooked anything obvious there.

I hope those aren't all old and known issues, I couldn't find  
anything about that in the list archive, though.

Best,
p.