Re: XPointer question

Terry Allen (tallen@sonic.net)
Thu, 3 Dec 1998 09:55:59 -0800

Charles Reitzel wrote:
| Ok. To do datatypes using NOTATIONs, and other useful things, I've got all
| "real" data in elements, not attributes. That's fine. I'd still like to
| use XPointer to point to a container element based on the values of one *or*
| *more* contained elements.
...
| Is there a way to do something similar if BROKERAGE_ACCT_NBR and
| BROKERAGE_CUSIP are child elements of FOV0001A_POSITION? It strikes me as a
| somewhat difficult problem in the general tree-oriented case, but easy in
| table oriented cases. Is there (or should there be) a special case to find
| elements by their immediate children? How do other folks approach this issue?

Partly because of low acceptance of xpointer syntax among some elements
of our programming staff I ended up writing a partial instance-based
query module instead of using xpointers in CBL. It seemed to me that
xpointers were okay for pointing into the tree one step at a time, but
weren't designed to do what you want; however, a query should be able
to do so. So maybe you're barking up the wrong tree and will have
to await whatever the W3C does with XML queries.

regards, Terry Allen

Terry Allen Veo Systems, Inc.
Business Language Designer 2440 W. El Camino Real
tallen[at]sonic.net Mountain View, Calif., 94040
Common Business Library - available at http://www.veosystems.com/