An introduction to Greenfox, a schema language describing file system contents
Schema validation is like a prototype of the declarative approach – to describe, rather than to code. The tutorial introduces to Greenfox, a schema language for file system contents. Resources are described by shapes, which are sets of constraints. The goals of the tutorial are twofold. First, it should help to get started with using Greenfox. Second, it should awake an awareness that the same set of constraints can be described in a less or more declarative way. This possibility is above all opened by a new possibility, offered by the upcoming version of Greenfox, to describe resource relationships independently of the constraints using them. Participants might acquire an increased awareness that it is not sufficient to ask “if” declarative or not, but we should also ask “how” declarative, think about degrees of declarativeness.
Hans is a developer with a keen interest in XML technology. He likes to claim that "XML has nothing to do with XML!", but what he really wants to say is probably that XML technology has nothing to do with XML syntax. Or perhaps even that XML technology is a way of thinking about information which does emphasize tree structure but is independent of any particular mediatype. When after several years of advocating it, he found his idea still as uncommon as a green fox, he decided to give it a name, which is Greenfox.