Re: [css-pseudo] please make sure pseudo-element "alt" property makes it into next ED

On 11/04/2014 03:27 PM, Alan Stearns wrote:
> On 11/2/14, 11:41 AM, "James Craig" <jcraig@apple.com> wrote:
>
>> It's been a couple years since CSS "alt" was proposed. The thread ended
>> with the implication that it was a necessary and useful idea, and that it
>> would be added to Editor's Draft. I was told no further action was
>> necessary.
>>
>>> Start of thread:
>>> http://lists.w3.org/Archives/Public/www-style/2012Nov/thread.html#msg233
>>>
>>> Tab's suggestion of "alt" property:
>>> http://lists.w3.org/Archives/Public/www-style/2012Nov/0317.html
>>>
>>> Clarifications:
>>> http://lists.w3.org/Archives/Public/www-style/2012Nov/0318.html
>>
>> And the property has been shipping in WebKit (as -webkit-alt) for about a
>> year now.
>>
>>> AX: Implement CSS -webkit-alt property (text alternative for generated
>>> content pseudo-elements ::before and ::after)
>>> https://bugs.webkit.org/show_bug.cgi?id=120188
>>
>> I'm re-sending this to www-style with the [css-pseudo] prefix because it
>> hasn't yet made it into a draft in the last two years.
>
> I’ve checked in a rough draft of the property:
>
> http://dev.w3.org/csswg/css-pseudo/#alt-property

I object to this change.
   a) I don't think this is a good solution to the problem.
   b) If we decide to add it, it belongs in the Content module alongside
      'content', not in the pseudo-elements module.
   d) Also, since we're currently tasked with publishing css-pseudo without
      this feature, I don't think the editors should be adding anything else
      without a WG resolution. (Also, in general, while I'm not particular
      about the order of drafting up text and getting a WG resolution on it,
      I don't think editors should be adding entirely new features without
      acquiring explicit WG consensus.)

Let me expand on a) since this is the technical, not process, ML...

The first *major* problem with 'alt' is that it cascades poorly. The
information you're trying to cascade there needs to be tied to the
information specified for 'content'. Since it's a separate property,
it will cascade independently, and likely the next style rule with
'content' will neglect to specify 'alt', leading to a mismatch between
'alt' and 'content'.

The second problem is that we already have solutions to this problem
that don't require an extra property (that cascades poorly):

Solution A, from CSS3 Generated Content:

   content: url(star.png), "alternate (fallback) text";

Solution B, from CSS3 Speech:

   @media speech {
     ... { content: "alternate text"; }
   }

Solution C, from CSS3 Speech:

   @media not speech {
     ... { content: "stuff with no speech equivalent"; }
   }

Why are we not pursuing deployment of these, instead of copying a
poorly-designed WebKit idea?

~fantasai

Received on Wednesday, 5 November 2014 16:48:49 UTC