Thank you very much David and Michael. Your explanations are great!

Please allow me to summarize what I've learned and then ask a question.

	Consider the construct copy-of(.)

	It instructs the XSLT processor to
	read (consume) the input and make
	an in-memory copy of the context
	node.

	You can do any navigation you like on
	that in-memory copy. That is, the nodes
	that result from executing copy-of(.) are
	not stream-processed.

	A construct is *grounded* if, when executed,
	it results in nodes that are not stream-processed.

	The construct copy-of(.) is *grounded* because,
	when executed, it result in nodes that are
	not stream-processed.

Is that correct?

Now for a question please. Yesterday Michael wrote:

	> Grounded expressions can be consuming,

Yes, I can see that. The copy-of(.) construct reads (consumes) the input and
results in nodes that are not stream-processed.

	> and non-grounded expressions can be non-consuming.

That is saying there are expressions which, when evaluated, do not read
(consume) the input and yield nodes that are stream-processed, right?

Would you give an example of this please?

/Roger