Transition from Legacy to Native rendering - (was Re: [whatwg] repetition model)

Hallvord Reiar Michaelsen Steen hallvors at
Mon Jun 14 08:37:34 PDT 2004

On 14 Jun 2004 at 0:58, Jim Ley wrote:

> I've also yet to see anything that shows the transition from script
> implemented to natively implemented. How will my legacy content work
> in these future native renderers - my script will still be there, how will
> the hypothetical native renderers know not to execute it?

I imagine the script libraries should be written with this in mind 
and themselves check whether the UAs support WebForms 2 natively.  
Something like..

if(! (document.implementation && document.implementation.hasFeature 
&& document.implementation.hasFeature('WebForms', '2.0') ) ){
    // create SCRIPT element or write SCRIPT tag linking in the WF2 
    // JavaScript libraries here

If it gets implemented first in Opera and Mozilla and they do not add 
support for CSS behaviours it is of course tempting to just use a CSS 
behaviour property for IE. Even so the script library itself should 
probably use hasFeature to avoid crashing with a native 

Ian, perhaps one ought to mention this somewhere if you write 
something about requirements for legacy UA-libraries?
Hallvord R. M. Steen

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