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Re: [css-syntax, ideas-needed] Merge/inherit lists of values.

From: François REMY <fremycompany_pub@yahoo.fr>
Date: Wed, 11 Apr 2012 09:51:17 +0200
Message-ID: <9C389C5F0AC341C0A01F8C135AA6DD5E@FREMYD2>
To: "L. David Baron" <dbaron@dbaron.org>, "Andrew Fedoniouk" <news@terrainformatica.com>
Cc: <www-style@w3.org>
There's a proposal I did some time ago called "List valued properties".

In short and with a sample:

    #el {
        transform: translate(-10,-10);

    .zoomed {
        transform[zoom]: scale(1.1); /* defines transform's "zoom" priority 
for #el.zoomed */

    .rotated {
        transform[rotation]: rotate(180deg); /* defines tranform's 
"rotation" priority for #el.zoomed */

    .zoomed:hover {
        transform[zoom] scale(1.2);


    #el1.zoomed.rotated {
        transform: concat-list(

    #el1.zoomed.rotated:hover {
        transform: concat-list(

Order proposal in a list is the following:

    1) Items having no ItemID are always last values.
    2) ItemID priority is the same as the specificity of the lowest 
specificity declaration where the ItemID is declared.

I also proposed:

    .specialEffect {
        box-shadow[]: a b c d; /* unique ItemID, don't allow override */

BTW, in the case my proposal is accepted, we could even solve Issue 1 of the 
css3-variables proposal:

    :root { var[NAME]: value; }
    xyz { property: var[NAME]; }

In such case, "element.computedStyle.var" would return all currently valid 
variables on the element.

Best regards,

-----Message d'origine----- 
From: L. David Baron
Sent: Tuesday, April 10, 2012 11:55 PM
To: Andrew Fedoniouk
Cc: www-style@w3.org
Subject: Re: [css-syntax, ideas-needed] Merge/inherit lists of values.

On Tuesday 2012-04-10 14:44 -0700, Andrew Fedoniouk wrote:
> used value of background-image-transformation will be this:
>    background-image-transformation: gamma(1.4) flip-x();
> I suspect that for implementation of such inheritance some change on
> CSS grammar/syntax level is required.
> I am thinking about something like !inherit modifier:
> div:dir(rtl) {
>    background-image-transformation: flip-x() !inherit;
> }

But this isn't about inheritance at all: this is about handling of
multiple rules applying to the same element (cascading) rather than
propagation of computed values from ancestor to descendant

We've previously discussed this sort of thing a few times under the
name "additive cascade", though never really come to any conclusion.

> I suspect that such inheritance feature could be useful for any other
> properties that accept lists of values. For example 'background'
> property that accepts lists of image definitions. In some cases
> it could be useful to combine two or more such list rather than
> to just override by heaviest rule.

Also counter-* and a few other things.


𝄞   L. David Baron                         http://dbaron.org/   𝄂
𝄢   Mozilla                           http://www.mozilla.org/   𝄂 
Received on Wednesday, 11 April 2012 07:51:48 UTC

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