- From: Jeni Tennison <jeni@jenitennison.com>
- Date: Wed, 14 Aug 2002 12:54:43 +0100
- To: xmlschema-dev@w3.org, Stefan Wachter <Stefan.Wachter@gmx.de>
Hi Stefan, > I have a question regarding attribute declarations whose use > attribute has the value "required". Must there be values for such > attributes in instance documents or is it also allowed to have a > fixed/default values filled in? The instance document must specify a value for the attribute [1]. I *think* that you're not allowed to specify a default value for a required attribute in the schema, because default values only apply when the attribute is missing, and if it's required it can't be missing, but I can't find the constraint specifying that at the moment. You can have fixed values for required attributes, however (particularly useful for indicating the version of a markup language). Cheers, Jeni [1] Clause 4 of http://www.w3.org/TR/xmlschema-1/#cvc-complex-type --- Jeni Tennison http://www.jenitennison.com/
Received on Wednesday, 14 August 2002 07:54:45 UTC