- From: Tim Berners-Lee <timbl@w3.org>
- Date: Wed, 28 Mar 2012 23:19:20 +0100
- To: Jesse Weaver <weavej3@rpi.edu>
- Cc: Hugh Glaser <hg@ecs.soton.ac.uk>, public-lod community <public-lod@w3.org>
On 2012-03 -28, at 21:25, Jesse Weaver wrote: > On Mar 28, 2012, at 6:44 AM, Hugh Glaser wrote: > >> Executive summary: >> TAG, please don't come back with something that does not allow, or even encourage, sites like Facebook to offer RDF back in return for: >> curl -L -H Accept:application/rdf+xml https://www.facebook.com/hugh.glaser >> They could do that - and "maybe 301 moved to the graph.facebook.com page >> PPS >> If you read through to here, or even if you just skipped to here, then if you really do send me your Facebook LD URI (along with one of more other ones to pair it with), I will drop everything and put them in sameAs.org :-) I see I have had it for a while in my FOAF file http://www.w3.org/People/Berners-Lee/card#i from which pointing tabulator at it I see all thee are identifiers for me: http://graph.facebook.com/512908782# http://identi.ca/user/45563 http://www.advogato.org/person/timbl/foaf.rdf#me http://www.w3.org/People/Berners-Lee/card#i http://www4.wiwiss.fu-berlin.de/bookmashup/persons/Tim+Berners-Lee http://www4.wiwiss.fu-berlin.de/dblp/resource/person/100007 and there is a seeAlso to the machine-editable http://dig.csail.mit.edu/2008/webdav/timbl/foaf.rdf foaf file > > BEGIN DIALOGUE > > Proponent: "I found a way to meaningfully publish our already-published data as Linked Data, and I've implemented a prototype." > > Developer: "Since you've already done it, let's take a look." > > Proponent: "Okay, go to [link]." > > Developer: "Hmmmm... [skip discussion about Turtle vs. RDF/XML]. Everything looks okay, except I notice these URIs have #me at the end. Why? Can't we just lose the fragment?" Proponent: Well, that's the local identifier. The way the web works is you take the local identifier in a file, stick the URI of a the file and hash in front of it and you've got yourselves. Developer: What, you mean like if I have a python program with some function defined like def foo(x,y) then on the web that would be myprogram.py#foo ? Proponent: You got it. Developer: Wow, cool -- so the web is just a way of making global identifiers for things in files in various languages? Proponent. Basically. Yes. Absolutely. Developer: Does it work for python? Proponent: No, not yet. Dev: What does it work for? Prop: RDF, HTML, Multimedia in general, XML ... maybe I am missing some Dev: Just those? Prop: Well, in the RDF world there are lots of languages which reference the same things, like other syntaxes like Turtle and RDF/XML, and more powerful languages like N3, and SPARQL and so on. So the RDF world is pretty big. Dev: But I can't mix those, right, I can't call a python function from HTML? Prop: No, as they are different things -- a type mismatch if you like. HTML is a markup language for hypertext, not programming language like Python. But there is crossover. You can embed RDF in HTML with RDFa, so the same document can defined HTML things and RDF things. Dev: What are HTML things? Prop: They are anchors, or any part of a document with an ID. Dev. <A> tags. Of course. Hmm. But RDF is, like knowledge, right, it can say stuff about *anything*. Prop: Yes. Dev: So I can make statements about HTML anchors? Prop: Yes. Dev: And about python functions? Prop: The moment a version of python comes out with a a spec for how localids work on the web, yes, totally. Developer: :-) Ok, well.... oh, by the way, in RDF I've seen people use an empty local id. Is that OK? Proponent. Well, yes, RDF doesn't specifically ban it, but lots of languages, perhaps future languages would have a hard time representing it. You can imagine. And HTML has special rules about what the empty local identifier means, and so on. Best keep away from it. Dev: Yes, you can't really have empty strings for identifiers in most of my favorite languages! ok, thanks, this all makes a lot more sense. So instead of <#> those folks should just use <#it>? Prop: The perfect choice. Dev: Ok, thanks it all makes a lot more sense when you look at it like that. Prop. You're welcome. You're leaving? Dev: Yes.. gtg ... though I'd code up a version of python which allows you to call things by global identifiers... hey, it would be pretty powerful... hang on a sec.. [exit L with laptop]
Received on Wednesday, 28 March 2012 22:19:32 UTC