On 26 Apr 2014, at 20:03, Dimitre Novatchev <dnovatchev@xxxxxxxxx> wrote:

> According to the XDM (both 2.0 and 3.0),
>
> "[Definition: A tree whose root node is not a Document Node is
> referred to as a fragment.]"
>
> So a fragment is a tree.
>
> However, I have been taught (by the books of Dr. Michael Kay) that an
> fragment is a node-set, that by itself may not be a well-formed
> document, but wrapping this node-set in a  single element parent will
> make this a well-formed document.
>
> There is an obvious contradiction in these two definitions -- in the
> former a fragment must be a tree (have a root node), while in the
> latter this isn't required.
>

Interesting. I'm not aware of any normative use of the XDM-defined term
anywhere in our specs, so I don't think it's a big issue. But I'm more
familiar with the use in the sense of the DOM DocumentFragment object, which
is essentially a Document without the constraint of having exactly one element
node and no text node children. Either that, or the URI "fragment identifier"
which means something quite different.

Michael Kay
Saxonica