Re: (no subject)

> hl=("hide"|"show")?
> ed=("enable"|"disable")?
> lr=("raise"|"lower")?
>
> state=attribute state {list {
>     (hl,((ed,lr)|(lr,ed)))
>   | (lr,((hl,ed)|(ed,hl)))
>   | (ed,((hl,lr)|(lr,hl)))}}
>
> start = element test { state }

Thanks all for your help.  David Tolpin's solution above works perfectly.
I'm just a newbie at this, but it sure makes schema writing more
pleasurable.