Re: Shelby's Final Position Paper on XBL

On Mon, 6 Jan 2003, Herr Christian Wolfgang Hujer wrote:
> [an exceedingly good summary ang glossary of Web terminology]
> If you consider a layer model:
> * Presentation
> * Logic
> * Content
> Where is Behaviour? It is crosscutting. It is an aspect, extending and 
> crosscutting the layers.

As you say, we (including myself) don't have enough experience to be
sure of anything here. However, I personally find that "Behaviour" is
more towards the Presentation side of your layer model than the

> I consider the a element of (X)HTML implying some behaviour.

Is there any programmatic behaviour of an <a> element that is
guarenteed to always be wanted?

I'm not sure there is. For example, I can't think of any similarity
between the behaviour of hyperlinks in Lynx and in Qube, except
changing the "location.href", and even that isn't guarenteed to be
always the case, for example I often open links in new tabs.

> I also consider most or all of the elements of XSLT implying some
> behaviour.

True, but they aren't presentational, so it's a rather different kind
of "behaviour" (not one which XBL is targetted for, I mean).

Basically, my point is that while I agree with you that Behaviour is
something that crosses several of the levels, it seems to me that the
parts of Behaviour that XBL addresses are most closely associated with
the Presentation layer.

> I definitely think CSS is the correct layer to add behavioural parts
> since there is no other layer until we create a new one and
> experience with behaviour is too little to well define and create
> such a new layer (and, as we know, behaviour is a cross cutting
> concern).


Note that XBL can also be linked using the DOM, and Hyatt has proposed
other linking methods too. For cases where CSS is clearly _not_ the
appropriate linking mechanism, there are alternatives.

Ian Hickson                                      )\._.,--....,'``.    fL
"meow"                                          /,   _.. \   _\  ;`._ ,.                         `._.-(,_..'--(,_..'`-.;.'

Received on Monday, 6 January 2003 12:04:38 UTC