Re: Profile issues

Hi,

I think one of benefits we can get from @profile is the prefix/term
resuability. So if the RDFa publisher wants to use dozens of vocabularies,
he or she does not have to put all of them in the @prefix one by one each
time. However, as said in Jeni's email, this will cause the dereferencing
issue when external profiles are off-line. My thoughts here are more from
the perspective of usability. These prefixes and terms should be reusable
but they need to be wrapped in the documents curated by some always-on-line
and change-less-frequently organizations (e.g., W3C, Yahoo!, Google,
Facebook, etc,). Hopefully, as time goes by, some of them will become more
pervasive and widely used.

Because the profile document is also defined in an "approved RDFa Host
Language" (or "other RDF serializations"), technically the profile in RDFa
can include other profiles as well. Profiles should not be retrieved
recursively and this has been mentioned in RDFa core 1.1 Maybe it will be
too extreme but I think each profile document should explicitly contain all
prefixes or terms about which the publishers are concerned and should not
employ other profiles (Maybe just <http://www.w3.org/ns/rdfa#> is needed but
it does not have to be wrapped in a profile document instead of being
attached with a prefix defination). If one profile does need prefixes
defined in another (i have not got a use case for this), these prefixes
should be copied from the latter to the former explicitly and within this
process, the profile curator is also responsible for avoiding the prefixes
duplication.

With respect to the duplicated prefixes, i think the prefixes defined by
publishers themselves using @prefix should always overwrite the same
prefixes defined in the employed external profiles because the formers are
more likely to be used during the publishing. It
is more tricky that the publisher employs more than one external profile
containing duplicated prefixes/terms which denote different URIs unless we
could add the prefix provenance information like "profile1:abc:
http://AmericanBroadcastingCompany#" and
"profile2:abc:http://AustralianBroadcastingCorporation#".

The above are my thoughts if @profile has to be there.

Xi Bai