I don't quite have a UPA friendly version of this grammar, but the  
optionality of hyphens and blanks between wordparts makes it a little  
different from the chess example. Imagine if black moves were  
optional in chess; then the model could be (W, B?)*, which obeys UPA.

In this case, though, there is a twist in that the final wordpart can  
be followed by a hyphen but not a blank, which is different from the  
other wordpart gaps. If ignore this difference, we get a little  
stricter model in the spirit of Michael's approach #2 (come as close  
as possible and rely on a subsequent processor to catch the missed  
cases. Here's a model that allows a trailing blank and/or hyphen:

     ((h, (w, (((h, b?) | (b, h?))?, w)+ ))
     |    (w,  ((h, b?) | (b, h?))){2, unbounded}
     )

where "{2, unbounded}" is the quantifier "minOccurs = 2, maxOccurs =  
unbounded".

xan

On Sep 15, 2006, at 11:34 PM, C. M. Sperberg-McQueen wrote:

>
> I can see three approaches to your problem in practice:
>
>
> (2) define an XSD rule that comes as close as you can to
> restricting the data without violating UPA, and use
> Schematron to supply the additional check.  Your rule
> might be:
>
>     ((h, (w, (((h, b?) | (b, h?))?, w)+ ))
>     |    (w,  ((h, b?) | (b, h?))?, w, (h | b | w)*)
>     )
>
> and Schematron rules can check that
>
>   each b is followed on the right either by a wordpart
>     or by a hyphen and then a wordpart
>   each hyphen is followed on the right by
>     (a) a wordpart, or (b) a blank and then a
>     wordpart, or (c) nothing


From mike@s... Mon Sep 18 21:53:18 2006
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