- From: Brian McBride <bwm@hplb.hpl.hp.com>
- Date: Mon, 16 Jul 2001 20:23:11 +0100
- To: rdf core <w3c-rdfcore-wg@w3.org>
I asked my colleagues if they had any use cases for anon resources that might help us with this issue. What follows is an (edited) response I received. Consider the case of describing services and being able to place adverts and offers for such services. For example here is an (massively simplified) advert requesting a service (all uri prefixes dropped for clarity): #advert123 :role "buyer"; :description [:product :roses; :quantity [:units :kg; :minValue "100"]]. And here is a supplier who can offer a range of services: #advert456 :role "seller"; :description [:product :roses; :quantity [:units :kg; :maxValue "500"]]. Neither is a specific service. The "buyer" advert is essentially a template. The seller is offering the existence of at least one service that matches a template - he may have many actual instances on offer which differ by location, qos etc. Here is an offer of specific service: #offer890 :inResponseTo #advert123; :instanceOf #advert456; :service #service42 #service42 :product :roses; :quantity [:units :kg; :value "200"]]; :deliveryTime [:units :days; :value "2"]; :deliveryMethod "TNT"; etc . Now. If we don't have anonymous nodes then we have the following problems. (1) In the seller advert it would appear that the seller is only advertising a single specific (but under-specified) service, #anon12345 or whatever, which would be hard to distinguish from an actual service instance like #service42. (2) Similarly in the buyer advert instead of describing a template, giving the service a URI would make it appear that I am looking for a specific service with that URI. This is clearly similar to DanC's book buying example. Brian
Received on Monday, 16 July 2001 15:25:40 UTC