Re: [xml-dev] Global Complex Types vs. Global Elements

["Rick Jelliffe" <ricko@allette.com.au>]

> Hi, all
>
> When I read XMLSPY 2005 User Manual today, I found the following statement
> which really baffles me.
>
> {{//http://www.altova.com/manual2005/XMLSpy/SpyEnterprise/globalelements.htm
>
> A globally declared element can be reused at multiple locations. __?___It
> differs from a globally declared complex type in that its content model
> cannot be modified without also modifying the global element
> itself___?___.
> If you change the content model of an element that references a global
> element, then the content model of the global element will also be
> changed,
> and, with it, the content model of all other elements that reference that
> global element.
>
> }}
>

I think this may be about complex type derivation. If you use a (globally
declared) complex type reference for an element, you can then
extend/restrict it for that element, without affecting any other uses of
the complex type. If you use a (globally declared) element, you can only
change the element's content model, which will effect everything that
references it.

Don't forget that that web page describes a product or the GUI of a product,
not XML Schema per se.

Just guessing...
Rick Jelliffe