Richard Tobin wrote:
> You would have to use a regular expression.  Something like
> 
>   "(apples|oranges|bananas|pears) (OR|AND) (apples|oranges|bananas|pears)"

I was trying to avoid this, as it gets more an more unwieldy the more 
items there are in the enumeration.

>>   <xs:restriction base="myAttributeValues">
>>
>>     <!-- WHAT GOES HERE TO ALLOW BOOLEAN EXPRESSIONS
>>          OF THE ENUMERATED TYPE VALUES? -->
>>
>>   </xs:restriction>
> 
> This is not going to work, since it's not a restriction of the base
> type.  If a type R is a restriction of a type B, then all legal R values
> are legal B values.  But "apples OR oranges" is not a legal value for
> myAttributeValues.

Would an extension work then? That would define a superset rather than a 
subset. I take it there is no way to indicate a token from some 
enumeration in a regular expression pattern? Is there any other facet 
that I could extend to achieve this? If not, I'll either have to use the 
regular expression workaround or else just leave it type="xs:string" and 
call it a day.

Thanks,
Steve