- From: Henry S. Thompson <ht@cogsci.ed.ac.uk>
- Date: 09 Sep 2002 08:58:16 +0100
- To: "Paul Kiel" <paul@hr-xml.org>
- Cc: <xmlschema-dev@w3.org>
"Paul Kiel" <paul@hr-xml.org> writes: > I believe I wrote about one of these situations before, but I > thought I would add a second issue, and reiterate the first. It is > regarding namespace coercion. I do like how powerful this technique > is but find parser implementation maddeningly inconsistent. I have > a suite of about a half dozen parsers that I test with to make sure > our schemas are interoperable. However, they implement namespace > coercion inconsistently. For other reasons, we are moving to a > different namespace usage, but our experience has taught us some > things about this technique that I wanted to share (and hopefully > save others the manual hair loss at trying to figure this out). > > Here are the scenarios. > > > Scenario 1 - one slave, two nested masters > > schema A (ns="A") > imports B (ns="B") > includes C (ns="") > > schema B (ns="B") > includes C (ns="") > > In this case, you want schema C to be coerced into both the A > namespace and B namespace in schema A. Some parsers coerce into > both, others only into one of the namespaces. Yup, early releases of XSV got that wrong -- the REC is clear that it's _schemas_ that are included, no schema documents, so there's really no doubt that doing two coercions is correct. > Scenario 2 - two slaves, one master > > schema D (ns="D") > includes E (ns="") > > schema E (ns="") > includes F (ns="") > > In this case, you simply want everything (E and F) to be coerced > into the D namespace, the slaves are merely nested. Some parsers > coerce both the nested dependents, others will only coerce the first > level, or E only. Same reason as above -- coercing the whole schema corresponding to the E schema DOC, which consists of components corresponding to both doc E and doc F, is correct. ht -- Henry S. Thompson, HCRC Language Technology Group, University of Edinburgh W3C Fellow 1999--2002, part-time member of W3C Team 2 Buccleuch Place, Edinburgh EH8 9LW, SCOTLAND -- (44) 131 650-4440 Fax: (44) 131 650-4587, e-mail: ht@cogsci.ed.ac.uk URL: http://www.ltg.ed.ac.uk/~ht/ [mail really from me _always_ has this .sig -- mail without it is forged spam]
Received on Monday, 9 September 2002 03:58:27 UTC