Re: Formal definition of HTML5 (was Re: Version information)

On Apr 13, 2007, at 12:41, Henrik Dvergsdal wrote:

> On 13. apr. 2007, at 11.05, Ian Hickson wrote:
>>> How will the HTML5 language be formally defined?
>> It's currently formally defined using English prose.
> But there will eventually be a formal language definition right? I  
> mean - you cannot validate documents against english prose.

You can write software that checks for the requirements given in the  
English prose.

> Sivonens validation service mentions a "prerelease schema".

The schema (RELAX NG and Schematron) is an implementation detail. It  
has no normative standing whatsoever (and, in my opinion, should not  
have). Moreover, the schema *cannot* cover all (X)HTML5 conformance  
requirements. Those requirements that it cannot cover, must be dealt  
with using a Turing-complete language. In fact, it would be perfectly  
permissible to implement a conformance checker 100% in a Turing- 
complete language without any schema at all. (But that would be more  
tedious than using schemas for the parts that schemas are suitable for.)

You can obtain a copy of the prerelease schema via anonymous CVS:
cvs -d login # password  
cvs -d co syntax

Henri Sivonen

Received on Friday, 13 April 2007 09:51:12 UTC