> It's reasonable to assume that generic text-aware XML software
> might be asked "please find all elements in a document which are
> expressed in German." It can't look for all elements with
> xml:lang="de" because they don't have this explicitly. So general
> mechanisms such as XPointers can't be used, and bespoke software
> must be written. This software (presumably) finds all elements
> which *do* have the attribute and continues recursively.
>From a logical perspective, your query is simply
Find all elements in a document where the element or the nearest
ancestor with a value for the xml:lang attribute specifies "de" as
the attribute's value.
With SDQL, for example, this test is surprisingly simple:
(equal? (inherited-attribute-string "xml:lang") "de")
Your point is well-taken, though: fragments of XML documents are often
tightly bound to their context (similar situations would involve
attributes for effectivity, security level, revision status, etc.).
All the best,
David
--
David Megginson ak117@freenet.carleton.ca
Microstar Software Ltd. dmeggins@microstar.com
http://home.sprynet.com/sprynet/dmeggins/