Re: Selectors as URIs?

Why is it important to use a selector as a fragment.

I'm getting from this thread that the selectors are attractively flexible
vs CFI (GREAT that's what we want) but not why the use case requires
fragments in any way.

Is there a need to link to something from or to an environment where the
selector cannot be communicated and handled separately by the viewer?

If we get into fragments I just wonder whether we shouldn't be campaigning
for an xpointer revival. Or maybe what I'm hearing is that ereaders are
willing to support fragments that browser vendors won't touch.

If you know your environment can accommodate your favorite selectors,
serialized in some known way, as URI fragments, there's nothing preventing
you from doing so.

On Mon, Apr 13, 2015, 10:07 Ivan Herman <ivan@w3.org> wrote:

> Hm. The problem is that there is a use case here that we may have to
> accommodate somehow.
>
> At the moment, if you take an Ebook, and you want to have a URI
> identifying a specific position within a specific chapter of a book, what
> you can use something like:
>
>
> http://www.example.org/book#epubcfi(/6/4[chap01ref]!/4[body01]/10[para05]/3:10)
>
> which identifies a position within a paragraph within a chapter of the
> book inside an EPUB package. It uses the epubcfi[1] specification of IDPF,
> which specifies an EPUB specific fragment ID.
>
> epubcfi works, and is used, but it has its drawbacks (let me not go into
> all the details). One drawback is that what it offers as anchoring
> possibility though powerful) is way less flexible than the selector model,
> primarily the range selectors. The conceptual model behind those would
> become useful, as an alternative to something like epubcfi, if those
> structures could be used as fragments. Maybe we have to restrict its usage
> and define it only for specific media types (text, etc) to avoid the issues
> in your example on genetic sequences or full blown graphics. But believe
> something like that would be very useful and, for some communities,
> necessary.
>
> Cheers
>
> Ivan
>
> (b.t.w., I am not sure I understand your comment on RFC3986)
>
> [1] http://www.idpf.org/epub/linking/cfi/epub-cfi.html
>
>
> > On 13 Apr 2015, at 18:28 , Robert Sanderson <azaroth42@gmail.com> wrote:
> >
> >
> > We discussed fragments in the community group at length.
> >
> > The concerns about the approach are documented here:
> >     http://www.w3.org/TR/annotation-model/#fragment-uris
> >
> > These boil down to the fact that as you get more sophisticated
> selections the URI becomes unbearably long.
> > Consider serializing an entire SVG document into the URI to specify a
> non rectangular area. Or selecting the previous and following 1024 Gs Cs As
> and Ts to select a range of text in a genetic sequence.
> >
> > My personal position is that selectors should not be turned into
> fragments, because (especially) that would break the rules of fragment
> identifiers as laid out in RFC 3986:
> >
> > The semantics of a fragment identifier are defined by the set of
> representations that might result from a retrieval action on the primary
> resource.
> > As further discussed by JeniT here:
> >     http://www.w3.org/TR/fragid-best-practices/
> >
> > Basically, unless there's a new text/HTML RFC that allows us to do it,
> we can't arbitrarily shove the description of the segment into its identity.
> >
> > Rob
> >
> >
> > On Mon, Apr 13, 2015 at 9:10 AM, Ivan Herman <ivan@w3.org> wrote:
> > (Although this may not be immediately relevant to the Working Group
> right now, I think the question *may* become relevant, hence my copy to it…)
> >
> > Rob, Paolo,
> >
> > a question came up at the Digital Publishing IG today. The IG is looking
> at general fragment identifiers for the purpose of identifying portions
> within a digital document (typically EPUB, but also some future versions of
> it). The Selector structure of the OA obviously gives a great model for
> various types of anchors, mainly when combined with other, existing
> fragment id definitions.
> >
> > However, at present, the selectors are defined in terms of RDF
> resources; to take an example from the spec, it says, for example
> >
> > selector": {
> >       "@id": "http://example.org/selector1",
> >       "@type": "oa:DataPositionSelector",
> >       "start": 4096,
> >       "end": 4104
> > }
> >
> > To be usable for a fragment identification, this structure should be
> turned into some sort of a, well, URI fragment. I mean, it is probably
> relatively easy to do this, something like
> >
> >
> http://www.example.org/#selector(type=DataPositionSelector,start=4096,end=4104)
> >
> > would do it but, of course, the ideal would be if that type of fragment
> format would be defined at one place.
> >
> > The question is: has this ever been discussed previously on the OA
> model? If it hasn't been done, should it be done? If it should be done,
> should it be done by this WG, or some other group?
> >
> > Thanks
> >
> > Ivan
> >
> >
> > ----
> > Ivan Herman, W3C
> > Digital Publishing Activity Lead
> > Home: http://www.w3.org/People/Ivan/
> > mobile: +31-641044153
> > ORCID ID: http://orcid.org/0000-0003-0782-2704
> >
> >
> >
> >
> >
> >
> >
> > --
> > Rob Sanderson
> > Information Standards Advocate
> > Digital Library Systems and Services
> > Stanford, CA 94305
>
>
> ----
> Ivan Herman, W3C
> Digital Publishing Activity Lead
> Home: http://www.w3.org/People/Ivan/
> mobile: +31-641044153
> ORCID ID: http://orcid.org/0000-0003-0782-2704
>
>
>
>
>