> I see notations as worsening this problem because they exist inside
> documents
I'm not sure what this means. Notation *declarations* exist within
documents, but all they do is bind a local name to the universal
name of the notation, like external parsed entity decls and namespace
decls. Notation *definitions* are global, like the IANA MIME-type
registry, but they piggyback on the URL system.
> and become management nightmares if the registry of whatever kind
> changes. Allowing information to identify itself when requested avoids
> this complication - the registry may not be any better, but at least I
> don't have to modify my documents to match up to the registry.
I should add one point to my potted summary:
The binding of (universal) MIME type names to their
specifications isn't allowed to change, except possibly
for allowing upward-compatible extensions, like new
characters in Unicode; for new semantics, new names (possibly
via parameters) must be introduced.
Overall, then, neither notations nor MIME types are subsets of the
other; each has special properties the other lacks.
Eliot scripsit:
> >Not to say that MIME types are bad,
> >only that I don't expect them to be around in 100 years. I do expect SGML
> >and XML, as *implementation and system independent standards* to be around
> >in 100 years.
MIME type names are also implementation- and system-independent,
though IANA is more de facto than ISO. Local renderers for them are not,
of course.
-- John Cowan http://www.ccil.org/~cowan cowan@ccil.org You tollerday donsk? N. You tolkatiff scowegian? Nn. You spigotty anglease? Nnn. You phonio saxo? Nnnn. Clear all so! 'Tis a Jute.... (Finnegans Wake 16.5)