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

On 15/04/2007 13:50, 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
> 
> ?
> 
> If not, what else do we need?

RELAX NG is an incomplete language for a document model, just like
doctypes or XML Schemas. RNG is not able at this time to specify the
default model of a "blank" element for content editing tools.
Let me give you an example : an ordered list contains one or more list
items but what should an editing tool do when the user inserts a "blank"
list ? A list with one blank item ? With two blank items ? With one item
with a predefined text node ?
It cannot better specify what's the default for the element following a
given element. In all existing web editor, when you press twice the
return key in a list item, the list breaks and a paragraph or a text
node is inserted. This cannot be specified in RNG. The fact that two
adjacent creations of an empty list item removes the empty items, breaks
the list and creates a new node cannot be specified.
RNG describes the model for tree validation purposes. It does not
describe the model fully.

To be sure about it, just answer this simple question : what is an empty
HTML document ?

</Daniel>

Received on Monday, 23 April 2007 10:44:46 UTC