RE: [relax-ng] converting relax ng schema to w3c schema?

["DuCharme, Bob (LNG)" <bob.ducharme@lexisnexis.com>]

>On Wednesday, June 19, 2002 8:11 PM, James Clark wrote:
> 
>For example, if a user wants a choice of attribute A or 
>attribute B, then they should express that intent in RELAX 
>NG.  The machine can tell that this cannot be expressed in 
>W3C XML Schema, can inform the user of this and turn 
>it into optionally attribute A and optionally attribute B. 

This is just what I pictured. As with converting to a DTD, or from any more
expressive language to a less expressive one, the necessary compromise gets
made and a comment within the deliverable notes that it was made. 

The scenario I pictured is that 

- an XML feed supplier (which has more of an agricultural ring to it than
it's supposed to) is using RELAX NG

- one of the customers isn't and requests a W3C Schema to use for validation
of the transferred documents because that's what their system uses 

- the supplier generates one from the RELAX NG one and sends it to them. 

The fact that the supplier's schema gave a choice between attribute A and B
is moot to the customer if they're using a schema language with no concept
of attribute choice, so preserving this information isn't such a big deal.

It sounds like Trang is getting to be a better and better tool for selling
RELAX NG, because a common concern of people likely to argue against it is
"what if the people we exchange data with are using W3C Schemas?" Now we'll
have something to give them.

Bob DuCharme          www.snee.com/bob           <bob@  
snee.com>  "The elements be kind to thee, and make thy
spirits all of comfort!" Anthony and Cleopatra, III ii