On Tue, Mar 30, 2021 at 1:13 PM Zimmel, Daniel <d.zim...@esvmedien.de> wrote:
> Duplicating the tree does indeed explain a lot > I don't think that, Xerces XSD 1.1 <assert> implementation duplicates creating XML fragment trees. The main validation logic for Xerces XSD 1.1 & 1.0 implementations occurs in a streaming fashion (its termed XNI [xerces native interface] within Xerces, which is similar to XML SAX events). Only when <assert> are encountered during XSD 1.1 validation processing, Xerces builds DOM tree and hands it over to the XPath 2.0 engine. The Eclipse XPath 2.0 engine (over which Xerces XSD 1.1 <assert> implementation is based upon, and is a third party dependency for Xerces XSD 1.1 implementation), requires the XDM (XPath data model) tree to be constructed as a DOM tree. > In general I always feel that XSD 1.1 adoption (and using assertions) is > not that widespread when I talk to other XML users/devs so I can understand > the incentive for improving this are quite non-existent. > IMHO, I differ with you somewhat on this point. The latest specs for XSLT (3.0), XQuery (3.1) and XPath (3.1) mention that, implementors of these languages can use either XSD 1.0 or 1.1 (this aspect is implementation defined) as a language for their type system. This I think emphasizes the importance of XSD 1.1 within the main XML based standards. The XSD 1.1 language has lots of new features (other than <assert>) as compared to XSD 1.0, which are significant improvement over XSD 1.0, and certainly it shall be prudent that XSD 1.0 users should consider adopting XSD 1.1. -- Regards, Mukul Gandhi
