(2nd) Mono meeting in Tokyo

Since Duncan is coming to Tokyo this weekend, we are going to have (2nd) Mono hackers meeting in Tokyo (yes, we had the first meeting two years ago). It is planned on 19th lunch time, at Umegaoka (close to Shimokitazawa). We'd welcome a few more people who would like to in join us (sorry but a few; we have no preparation for large meeting). Please feel free to mail me (atsushi@ximian.com) if you are interested.

One of the reason why XmlSchemaValidator does not rock

After hacking label collector functionality for RELAX NG, I noticed that .NET 2.0's XmlSchemaValidator is kind of such an API (note that the link to MSDN documentation above shows so obsoleted). So I decided to implement it nearly a week ago. And now it's mostly implemented and checked in mono's svn (I think it is one of the hackiest xsd validator ;-).

Here is an example application of XmlSchemaValidator I wrote to test my implementation (it compiled with 2.0 csc).

Some of you might know that implementing XmlSchemaValidator sounds weird, because there is no API documentation for this new face (well, at least for VS 2005 October CTP which I reference). But the functionality is mostly obvious (at least to me). For example, ValidateElement() is startTagOpenDeriv, ValidateAttribute() is attDeriv, and ValidateEndOfAttribute() is startTagCloseDeriv (btw I really don't like those method names) described in James Clark's derivative algorithm for RELAX NG. One thing I was mystified was what ValidateElement(string,string,XmlSchemaInfo,string,string,string,string) overload meant, but thanks to MS developers, it was solved.

Actually XML Schema is much useless than RELAX NG stuff. XmlSchemaValidator is fully stateful, thus you cannot go back to the previous state easily. RELAX NG derivative implementation is stateless, so you can just attach those derivative instances to nodes in the editor. Oh, yes, XmlSchemaValidator could be stateful, if it supports cloning. But I don't think it can be lightweight.

btw, if you want, you can generate xsd from DTD and use XmlSchemaValidator, if you want.