Re: [XBL] XBL 2.0 Expected context, Expected children

On Tue, 10 Oct 2006, Karl Dubost wrote:
> Le 06-10-06 à 08:41, Ian Hickson a écrit :
> > On Thu, 5 Oct 2006 karl@w3.org wrote:
> > > 
> > > # When an XBL element is found inside an element other than that listed
> > > # as its "Expected context", it is in error.
> > > 
> > > 1. Please define an "expected context" and "expected children" in 
> > > Terminology.
> > 
> > I don't understand what the definition would be. The reader will 
> > immediately see what is being referred to as soon as they look at the 
> > next section, since the headings are highlighted and everything. 
> > However, in an attempt to resolve this, I've slightly changed the 
> > sentence you quoted above to work around this.
> 
> The sentence is better.
> Are there unexpected contexts? Is "expected" word necessary?

Well, any context that isn't expected is unexpected.


> > > 2. It seems to be important enough to the specification. Please, 
> > > define a schema (any kind) that gives a programmatic way of checking 
> > > the expected context or expected children.
> > 
> > I am not aware of any language that is expressive enough to 
> > unambiguously and fully describe the syntactical requirements of XBL2.
> 
> Do you mean because of multi namespaces? What are the precise 
> syntactical requirements which can't be expressed?

Well, for instance, how do you express the syntactic requirements for the 
"includes" attribute? (i.e. that it must contain a syntactically valid 
Selector?)

Or, at the element level, how do you express the content model of the 
<template> element, which says that its descendants can include <content> 
and <inherited>, that <content> elements can't be nested (even 
indirectly), but that those elements may not be somewhere that isn't a 
<template>, and that also allows a couple of XBL global attributes on any 
descendant of <template> that isn't in the XBL namespace?

Or, hwo do you express the content model of the <script> element, given 
that it is dependent on the script-type="" attribute on the <xbl> element?

-- 
Ian Hickson               U+1047E                )\._.,--....,'``.    fL
http://ln.hixie.ch/       U+263A                /,   _.. \   _\  ;`._ ,.
Things that are impossible just take longer.   `._.-(,_..'--(,_..'`-.;.'