How to best implement "optional" in YACC?

I'm creating a YACC grammar to read a file type that has lots of optional
elements in it, but the elements have an order.


The spec looks something like this:


test: foo bar? bazz? buzz yark? yutz


where the stuff with ? may or may not be present. Sometimes I get like 5
or 6 optional items in a row. Is there a way to do this without
explicitly defining all the permutations?


Right now, I've chickened out and done something like:


test: foo optionalstuff buzz moreoptions yutz


optionalstuff: /* possibly empty */
| optionalstuff oneoption
;


oneoption: bar
| bazz
;


Are there better ways to handle this?


Kent
kentq@world.std.com
[Try this:
test: foo optbar optbazz buzz optyark yutz ;
optbar: bar | /*empty*/ ;
optbazz: bazz | /*empty*/ ;
optyark: yark | /*empty*/ ;
-John]
--

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