Is there a neat way in syntax glossing to indicate "these are all optional, but at least one of them must be there"?

Question

I'm talking about a general case of the following situation:

*( (x) (y) (z) (w) ) lorem ipsum

where the positions for the optional elements are not contiguous.

For example, they may occupy the following positions:

(x) lorem (y) (z) ipsum (w)

but

* lorem ipsum

Is there a succinct way to indicate this is the case?