On 20/12/2007, at 5:51 AM, Danny Ayers wrote:
Coupla quick comments - I accept most of your arguments for not making the language fully generalised (despite being a fan of both SPARQL & XPath). But what I'd caution though is making the language more specific than it needs to be, the other points being equal. To avoid reinvention, a selective reuse of XPath constructs would seem to make sense, with added sugar for Atom. Can your proposal be systematically mapped to XPath?
I believe so, although I haven't done the work; as I said in a response to Brian a few minutes ago, other folks who want to implement with XPath 2.0 have looked at it and believed that it's possible (and relatively easy). Brian's message seems to support that.
Having said that, although XML-orientation seems obvious given Atom (and the possibility of using URI path parts..? ok, I only skimmed your draft), I wouldn't entirely dismiss SPARQL-like features. Typed links *are* important in Atom, so some kind of triple patterns could be very useful.
Yes, links are definitely not a strong point in the current draft (you can index them with @path, but it's fairly "dumb"). Do you have specific use cases in mind?
As another ref, I'd suggest checking out Microsoft's Project Astoria - it's essentially a RESTful front end on top of an entity-relation backend model. Like RDF but without URIs as entity/relation identifiers (baby...bathwater...hmm). But one thing I saw a demo of which looked very promising was their query URI construction. I can't find the spec proper, but there are some examples here: http://alexbarnett.net/blog/archive/2007/04/30/microsoft-codename-quot-astoria-quot-data-services-for-the-web.aspx
Thanks, I've looked at it before, but I'll have another. Cheers, -- Mark Nottingham http://www.mnot.net/
