[plt-scheme] Objects, classes and match

Hi all,

Is there any way to use match on an object? I can't see anything in  
the docs (although I may be missing something obvious). Something like:

     (match (new my-class%)
       [(struct my-class% (a b c))
       ...])

I don't mind setting up a custom match-expander. I suppose I could  
convert the object to a vector and match on that. That doesn't seem  
like a particularly efficient solution, though.

Cheers,

-- Dave