About using xs:unique on xsi:type in a sequence

Question

It is possible to have a unique constraint on an element\'s type ?

Let\'s say I have a Noah\'s Ark where Animal/@name must be unique.

Below\'s an XML that do not

Answer 1

Thanks for your response.

Just for fun I made an attempt with Schematron ; however I couldn't make it work since the XPath expression I find out uses "current()" which is not available in oxygen or XMLSpy, so I can't test it :(

    
    
        
        
            
                
                    name not unique !