Re: Designing Schemas for Backward and Forward Compatibility - XML Schema, Relax NG, Schematron

Sorry for revisiting this topic. While reading Roger L Costello's summery at:

http://www.xfront.com/backward-forward-compatibility/

I realized that the compatibility will break if people actually take advantage of the <any> in the <other> and put various elements in it, e.g.,


<Book>
    <Title>My Life and Times</Title>
    <Author>Paul McCartney</Author>
    <Date>1998</Date>
    <ISBN>1-56592-235-2</ISBN>
    <Publisher>McMillan Publishing</Publisher>

    <Other>
        <namespace1:tag1>blah</namespace1:tag1>
        <namespace2:tag2>blah blah</namespace2:tag2>
    </Other>
</Book>

These blah blah things are not supposed to be standardized. People just find them useful yet no consensus has been reach to include them in the future schema. Any idea how to prevent this?

Thanks,

Zhiwu