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Hi Roland,The main reason for the difference is that when we added the <creator> element (and others), we didn't spend the time to think about whether or how to make them into xlinks. The XLinks we do use are "simple" type xlinks. There is a lot of semantic richness to XLink that we just haven't spent the time to delve into. I think, for instance, that we could make the <creator> element into an "extended" type XLink linking to both the creators home page and email but we haven't looked into it.
We are certainly open to any suggestions on how XLink could/should be used in the THREDDS specs. Does anyone have much experience with XLink usage and how XLinks are being used in various applications?
Ethan Roland Schweitzer wrote:
Hi Folks,I was just studying the 1.0 Catalog Spec to see what I would like to steal for defining a more complete LAS metadata element.When defining the <documentation> or <metadata> element, references to external URLs are specified using XLink attributes, but when defining a URL pointing to an external reference for the <creator> element a simple "url" attribute is used.What is different about these two situations that lead to the choice of XLink attribute group vs. a single "url" attribute?Roland
-- Ethan R. Davis Telephone: (303) 497-8155 Software Engineer Fax: (303) 497-8690 UCAR Unidata Program Center E-mail: address@hidden P.O. Box 3000 Boulder, CO 80307-3000 http://www.unidata.ucar.edu/ ---------------------------------------------------------------------------