[xslt] How can I tell the type of output I receive?

[David Hyatt <hyatt apple com>]

I am very close to having a basic transform working in Safari.  I am 
using the following function:

xsltSaveResultTo

And I have collected the output from this call.  The problem is that I 
now need to do three different things with this output depending on 
whether it's HTML, XML/XHTML, or text.  I notice from looking at the 
source that xsltSaveResultTo has a lot of logic for figuring out what 
the type of the output is before it actually does the serialization.  
Is there any way that I can get to this information, or is it not 
exposed yet?

If it isn't exposed, could xsltSaveResultTo be enhanced in some way to 
provide some indicator of the type of the output?

Thanks!
dave
(hyatt apple com)