multiple attribute groups for an elment possible?

Hi all,

 

I'm trying to figure if it's possible to have essentially several valid
attribute groups per element.  For instance, if I have two types of
symbols,

 

<symbol type="a" a="val" b="val" c=123 />

<symbol type="b" x="val" y="val" z=123 />

 

I would like to say that type "a" has these required/optional
attributes, i.e. a, b, and c, and type "b" a different set, i.e. x, y,
and z.  Is it possible to say that "symbol" can have one of several
attributeGroups?

 

I realize I can just make aSymbol and bSymbol but would like to avoid
that route.

 

Cheers,

Zach
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