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Re: Access to Schema API information

From: Michael Kay <mike@saxonica.com>
Date: Tue, 22 May 2012 09:23:37 +0100
Message-ID: <4FBB4D09.9040504@saxonica.com>
To: w3c-xsl-query@w3.org, "xmlschema-dev@w3.org" <xmlschema-dev@w3.org>

On 21/05/2012 19:55, Casey Jordan wrote:
> Michael,
> This is really awesome.
> I would be very interesting in learning more/helping in anyway. My 
> biggest questions would be around efficiency. The SCM's can get pretty 
> large. Is the SCM structure managed through the java backend to 
> provide quick access?
I think individual calls on the interface will be very efficient. The 
performance risk is that some processing of the SCM might require very 
large numbers of calls, because the information is not available in the 
required form. For example, there's no direct way to determine the 
members of a substitution group other that searching all element 
declarations to see if they belong. Saxon has this information 
internally, but the SCM properties don't expose it (for a fairly good 
reason - adding a new element declaration to a schema should not change 
the properties of existing element declarations).

I could extend the model to expose additional properties of objects, but 
that's starting to depart from being a completely standards-based interface.

Michael Kay
Received on Tuesday, 22 May 2012 08:24:26 UTC

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