Re: [css3-background] clarify which properties in this module apply to ::first-letter and ::first-line

On 03/28/2012 12:09 PM, fantasai wrote:
>
> Now, there are two approaches to categorizing the properties in css3-background
> into "applies" and "doesn't apply" buckets for ::first-line
>
> A) Things considered "background" properties apply, those considered "border"
> properties don't apply. So determine which bucket each property falls into.
> This is somewhat ambiguous for things like border-radius and box-shadow.
>
> B) Go back to the principles of *why* border was excluded from ::first-line
> and why background was not, and derive the categorizations from that.
>
> You're trying to do A. Brad is trying to do B. This is why you're disagreeing here.
> ...
> Anyway, this thread leaves us with three proposals:
>
> 1) Interpret all 'border-*' properties as "border properties" per 2.1, and
> exclude them all.
> 2) Interpret all properties reset by the 'border' shorthand as "border
> properties" per 2.1, and exclude them all. Include 'border-radius'.
> 3) Exclude only layout-affecting properties, i.e. only the CSS2.1 "border
> properties". Include 'border-radius' and 'border-image'.

Okay, so here's proposed wording for various solutions:

Proposal 1:
   All properties in this module apply to the ::first-letter pseudo-element.
   The _background properties_ also apply to the ::first-line pseudo-element.
   The UA may, but is not required to, apply the border-radius, border-image,
   or box-shadow properties to ::first-line. The UA must not apply the
   _border properties_ to ::first-line.

   ::first-line summary:
       MUST:
         all background properties
       MAY:
         any other properties that don't affect layout
       MUST NOT:
         properties that affect layout

   Variant: shift 'box-shadow' into MUST NOT category

Proposal 2:
   All properties in this module apply to the ::first-letter pseudo-element.
   The _background_  and _border-radius_ properties also apply to the
   ::first-line pseudo-element. The UA may, but is not required to, apply
   border-image or box-shadow properties to ::first-line.
   The UA must not apply the _border properties_ to ::first-line. [CSS21]


   ::first-line summary:
       MUST:
         all background properties and border-radius
       MAY:
         any other properties that don't affect layout
       MUST NOT:
         properties that affect layout

   Variant: shift 'box-shadow' into MUST NOT category

Proposal 3:
   All properties in this module apply to the ::first-letter pseudo-element.
   The _background_, _border-radius_, and _border-image_ properties also apply
   to the ::first-line pseudo-element. The UA may, but is not required to, apply
   box-shadow to ::first-line. The UA must not apply the _border properties_ to
   ::first-line. [CSS21]

   Variant: shift 'box-shadow' into MUST NOT category

I'm leaning towards 1 or 2. Don't have a preference between them, but do have
a preference for allowing box-shadow rather than disallowing it: I don't see
a benefit to making an implementation that supports it non-conforming.

~fantasai

Received on Monday, 2 April 2012 22:53:31 UTC