Re: [cssom] Defining getComputedStyle

On Thu, 11 Feb 2010 18:00:43 +0100, Boris Zbarsky <bzbarsky@mit.edu> wrote:
> On 2/11/10 11:41 AM, Anne van Kesteren wrote:
>> I don't. All I have is that browsers do not really agree. I could be
>> convinced to make these "exceptions" too. I do not really feel strongly,
>> though less exceptions seemed better.
>
> Less exceptions is definitely better, as long as it doesn't break  
> existing content.  That "as long" is the issue.

I'm not sure how we'd get good data on this other than by shipping  
alpha/beta products. That WebKit does not them specially is a positive  
indicator, though of course there could be different code branches. (Opera  
is somewhat broken with regards to getComputedStyle. I have not taken its  
behavior into account when making decisions.)


>>> It's not a shorthand in CSS 2.1.
>>
>> Well, CSS doesn't have versions and most browsers have implemented
>> overflow-x and overflow-y.
>
> This is going to be a general problem as various properties that are not  
> shorthands become shorthands (things like white-space for example).  Do  
> we just want to take it on a case-by-case basis, or try to figure out  
> how to handle it?

If we can figure something out that would be great.


> For what it's worth, the Gecko behavior for "overflow" is to return a  
> value if the x and y values are equal and to treat it as a shorthand  
> otherwise.

For overflow-x:visible; overflow-y:auto I get auto back as resolved value  
for overflow in Gecko. Though for a combination of hidden and visible I  
indeed get nothing.

I suppose something needs to be defined here after all.

What we could do is return values for all shorthand properties unless the  
individual properties make that impossible. E.g. border-color with four  
different colors does not fit in border. However this has the potential  
for breaking pages as well if they expect the empty string for some reason.


-- 
Anne van Kesteren
http://annevankesteren.nl/

Received on Thursday, 11 February 2010 17:15:29 UTC