RE: CSS-Tranformation mechanism and modularizing CSS

Sjoerd Visscher [mailto:sjoerd@heeten.nl] wrote:
>This was a proposal to do this, concerning element attributes. 
>It's relatively simple to implement, considering that the content 
>property already exists and that BECSS requires the same functionality.

That's an interesting assertion.  BECSS requires a subset of that
functionality, as it only concerns event handlers, not arbitrary attributes.
Especially with the advent of XML elements mixed in HTML, I'm not so sure
this is as simple as you think.  I believe this would be a considerable task
(not impossible, mind you - but not "relatively simple", either) in the IE
codebase.

>Considering the relatively low amount of extra coding to implement such
>powerfull things as:
>IMG[src2]:hover { @attributes { src: attr(src2); } }

Again, I'm not sure how you're sure that this is a relatively low amount of
extra coding.  Have you implemented it as an experiment in Mozilla or
something?

I'd also point out that you're setting the src attribute based on a state
here - what happens if someone comes in through script and explicitly sets
the src to something else while you're in that state?  What happens, then,
when you move the cursor away?  There is a considerable amount of
specification work that would need to be worked on here, with a model for
how attributes set through your proposed stylesheet extensions interact with
those set in the document and the access through the DOM.

BECSS is a smaller set of capabilities, which is designed to solve a
distinct set of problems that a few vendors knew through implementation
experience that they had.

>Moreover: consider the way BECSS will be implemented. If an event is fired,
>the implementation has to check in the CSS-properties if there is a handler
>defined, and else look in the document tree. This will be hacked with a lot
>of if_then_else statements for each eventhandler. It's much nicer to modify
>the code for the content property and code a general way for CSS to provide
>alternative attributes to the original document.

I don't know about anyone else, but I would move the event handlers to be
handled in the cascade, just like font-size is.  I don't see any need for
extensive if-then-else statements; less so, in fact, than if I just plugged
in an arbitrary-attribute-setting mechanism.

-Chris Wilson

Received on Monday, 4 October 1999 18:32:51 UTC