Re: Cool XPointers Do Change?

"Danny Ayers" :
> Hi Sean & all,
> I've been playing with XPointer a bit (trying to hack annotations a la
> Annotea) and though some of the points you raise are exactly the things
I've
> had trouble with, I'm not sure about your reading of the spec. The way
I
> read it is that an XPointer expression simply adds a bit of fine detail
to
> what you'd get with XPath or DOM2 - presumably going back to the
Infoset
> (but those are murky waters that I find a bit scary). But if document a
has
> XPointer expression B, then it's tied to that document whether we like
it or
> not.

Yep, which means it can't be a fragment id on a http:// resource as that
isn't a document, it could be anything the document is only one
representation, and XPointer are only valid for that representation,
current fragment IDs are valid for all.

http://LordofTheRings/#FrodoGetsTheRing   makes sense whether the
document you get back is the film, the book, the film script or whatever
the representation of the resource the request returns (based on accept
headers or whatever.)  whereas  http://LordofTheRings/#xpointer(page=57)
only makes sense for the book.  This means I can't send you that url and
have it mean anything unless I also tell you what accept-headers to send
(and what if you get the large print version?)

XPointers are very useful for specifying things in documents, but they
shouldn't be considered a fragment of the url, they are pointers within
documents not pointers within urls.

Jim.

Received on Tuesday, 11 December 2001 07:18:13 UTC