xlink:hrefs (ODF all versions)

Dear all,

Throughout ODF, the xlink:href attribute is used to point to resources.

* Some of the time it is not stated what syntax this attribute value
shall have. Presumably it is an IRI or URI Reference. It should be
clearly and consistently stated.

* What is the base for resolution of relative references (assuming they
are allowed).

* Any re-basing facilities? Can an xml:base be incorporated/respected?

* Often it is mentioned such attributes specify a "file". Is it really a
restriction then that "files" only can be referenced, or are more kinds
of resource permitted?

* Sometimes the XLink spec is ignored and the attribute can contain
arbitrary information such as in 18.912.21 where it can contain
"information on how to make a connection to a database". (It is also a
defect that this "information" is not specified here).

* Presumably on occasions there are further restrictions on the MIME
type of the referenced resource and/or rules for how the returned
information is to be processed.

A thorough pass needs to be made of the ODF spec making sure these
issues are resolved for every mention of the xlink:href attribute.

Note that if the W3C's namespace is used, no substantive deviation from
their recommendation[1] is permitted (or, at least, W3C and JTC 1 will
not be very likely to permit it). If it is desired to deviate from the
existing standard, a different Name has to be used.

[1] http://www.w3.org/TR/xlink/#link-locators

- Alex.