- From: Henri Sivonen <hsivonen@iki.fi>
- Date: Sun, 15 Apr 2007 16:00:08 +0300
- To: Henrik Dvergsdal <henrik.dvergsdal@hibo.no>
- Cc: public-html@w3.org
On Apr 15, 2007, at 14:50, Henrik Dvergsdal wrote: > Is it possible to specify all machine-checkable criteria in > XHTML5 by means of: > > A RELAX NG schema which refers to > > 1. A datatype library > > 2. A set of formal rules, specifying, for instance, table integrity > requirements A RELAX NG schema cannot refer to a generic "set of formal rules". I take it that you meant to ask if XHTML5 conformance can be defined as an XML document satisfying a RELAX NG schema and a "set of formal rules" (without the schema actually doing the referring). In theory, yes, but the "set of formal rules" would just be a catch- all notion for everything that the RELAX NG schema doesn't cover. To implement a conformance checker, you eventually need to have running code that checks for all the stuff that the RELAX NG schema didn't cover. With the current WHATWG spec model, a human (me) takes English as the input and produces a computer program as the output. You seem to be suggesting adding an intermediate formalism. If an intermediate formalism was added, the interesting question would be how to get from the formalism to running code. Would the formalism be a computer-readable new schema language, so that one would have to implement a validation engine for it? Or would a human software developer still read the formal stuff as the input and produce a program as the output? If you meant the former, you'd end up inventing a declarative programming language as the formalism and have the spec editor develop a conformance checker in that programming language. (Or alternatively, you'd end up with an XHTML5-specific schema language and the purported validator for the schema language would essentially contain the kind of code that I have implemented.) If you meant the latter, I don't see how the added level of indirection between English and running code would help. -- Henri Sivonen hsivonen@iki.fi http://hsivonen.iki.fi/
Received on Sunday, 15 April 2007 13:00:27 UTC