Jan Algermissen wrote:
Murray Altheim wrote:
Jan Algermissen wrote:
Murray Altheim wrote:
[...]
Do people have to be aware of the list of IDs, or does
the system just fail when either an expected ID isn't there, or
when an inserted ID fails because it's already in use (or there is
an error because of that ID).
IMHO using element IDs for other referencing purposes than for reconstructing
the serialized graph are a bad choice anyway (as are PSIs that contain fragment
identifiers) due to the limitations they introduce when used over HTTP....
Hmm. I'm confused about that last statement. If I publish a Topic
Map as a source of PSIs, or an XHTML document that references an
XTM document acting as that source, either way I have a single
XTM document containing multiple <topic> elements, where each is
potentially the Topic "behind" that the published PSI. I do this
because the PSI is yes, just a string, but the Topic is perhaps
firmly interwoven in a lattice of relations that might be important
to my processor. So those fragment IDs are important to me. Being
over HTTP or not doesn't seem to make a difference here. It's a
reference on a local file system too.
The problem with fragment identifiers is, that they are not part of the
message when you invoke a HTTP method on them. The consequence is that
no intermediary will see them and thus cannot add-in information it
might have about that URI.
I don't mean to be snide, but that's not my problem. :-)
You are perhaps looking at this from the REST POV? I'm looking at
it from a server POV. The HTTP server certainly receives everything,
so the fragment identifiers do exactly what they should do upon being
received, i.e., they point at a specific ID within the resource. All
of this information is passed on to the application, right?
Another problem is that creating flat namespaces (a single 'document' with
lots of significant fragments) will allways cause the whole document to
be transfered just to access the fragment (as said, the server will never
see the fragment, the user agent strips it off).
Again, I'm looking at this from a server POV. The server doesn't have
to transfer everything if the ID is a part of a query.
A more practical example is that you cannot, for example, submit a fragemnt
identifier-URI to a search engine for indexeing. foo#1 and foo#2 are
exactly the same thing to them.
Same answer as above.
Perhaps we're talking about different things?
[I'll leave off discussion of encoding, since Lars Marius has
answered that already.]
Murray
......................................................................
Murray Altheim http://kmi.open.ac.uk/people/murray/
Knowledge Media Institute
The Open University, Milton Keynes, Bucks, MK7 6AA, UK .
US envoy warns of Taleban return, BBC News
http://news.bbc.co.uk/1/hi/world/south_asia/3402813.stm
When asked about concerns that the US call for "acceleration"
[on building up the Afghani army to fight the resurgent Taleban]
was linked to the timetable of American elections in November,
Mr Taylor said: "We all remember what happened in the United
States [on 11 September, 2001] and where those attacks came from."
Saudi Arabia? The attacks did not come from the Taleban, who
are only concerned with control of their own country.
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