- From: Terry Allen <terry@ora.com>
- Date: Tue, 3 Jan 1995 13:09:19 PST
- To: Larry Masinter <masinter@parc.xerox.com>, rdaniel@acl.lanl.gov
- Cc: uri@bunyip.com
| We can't eliminate the chaos that already exists in the world of | meta-data for documents; trying to invent a 'core' set doesn't reduce | the chaos, in fact, but rather adds to it, by introducing yet another | *new* attribute set. Not chaos, but variability. Anyway, | Naming each attribute *set* rather than each individual attribute will | reduce the length to be something managable. It might be possible to | also allow individual attributes to be named even if they don't occur | in the overall set. | <urc scheme="urn:iana:here.there.org:foo"> | <author>...</author> | <title>...</title> | <author scheme="urn:iana:banana.br:trigram"> | </author> | </urc> This example seems to mix one overall scheme (here...) with a scheme local to an individual element (banana...). Wouldn't it be better to offer instead only a choice of overall schemes, on the assumption that the components are defined by the overall scheme? If that's to be done in SGML (which I am not advocating), schemes with different URCs will have different allowable contents. It is one of SGML's weaknesses that attributes can't affect content models (you can't say in the DTD that <urc scheme="foo"> shall contain only those elements allowed by scheme foo). So a better approach (if SGML is really desired) would be to have one element for each flavor of URC: urc.foo, urc.here, urc.banana. Then in the DTD one could require that urc.foo have only the desired content. -- Terry Allen (terry@ora.com) O'Reilly & Associates, Inc. Editor, Digital Media Group 103A Morris St. Sebastopol, Calif., 95472 A Davenport Group sponsor. For information on the Davenport Group see ftp://ftp.ora.com/pub/davenport/README.html or http://www.ora.com/davenport/README.html
Received on Tuesday, 3 January 1995 16:11:32 UTC