W3C home > Mailing lists > Public > www-style@w3.org > November 2011

Re: Composite pseudo classes

From: Brian Kardell <bkardell@gmail.com>
Date: Wed, 9 Nov 2011 11:59:00 -0500
Message-ID: <CADC=+jcfq0FcfLvp1Pwq1-kYEM9UBfxsU-tB=r5XP-qH-Jb6cA@mail.gmail.com>
To: "Tab Atkins Jr." <jackalmage@gmail.com>
Cc: Pete Boere <pete@the-echoplex.net>, www-style@w3.org
Has the advantage of being pretty easy to implement too... :)

If you are a jquery/sizzle user and have grown accustomed to their
extensions the following snippet would then cause 13 of them to be
immediately useable in your regular CSS too...

@alias jq-button      input[type=button];
@alias jq-checkbox    input[type=checkbox];
@alias jq-file        input[type=file];
@alias jq-header      h1,h2,h3,h4,h5;
@alias jq-image       input[type=image];
@alias jq-input       input,textarea,select,button;
@alias jq-password    input[type=password];
@alias jq-radio       input[type=radio];
@alias jq-reset       input[type=reset];
@alias jq-selected    option[selected];
@alias jq-submit      input[type=submit];
@alias jq-text        input[type=text];
@alias jq-parent      :not(:empty);




On Wed, Nov 9, 2011 at 11:42 AM, Tab Atkins Jr. <jackalmage@gmail.com> wrote:
> On Wed, Nov 9, 2011 at 4:15 AM, Pete Boere <pete@the-echoplex.net> wrote:
>> Usually when using the :hover pseudo class it is appropriate to also use the
>> :focus pseudo class for accesibility reasons. [1]
>>
>> Is it possible to have composite pseudo classes for this purpose?
>> I've implemented a kind of composite pseduo class in a PHP CSS
>> preprocessor[2] like this:
>>
>> .nav a:hocus { ... }
>> .nav a:pocus { ... }
>>
>> compiling to
>>
>> .nav a:hover, .nav a:focus { ... }
>> .nav a:hover, .nav a:focus, .nav a:active { ... }
>>
>> internally a substitiution is being made using an :any (:matches) shim [3]
>> :hocus => :matches(:hover,:focus)
>>
>>
>> [1]
>> http://www.456bereastreet.com/archive/201004/whenever_you_use_hover_also_use_focus/
>> [2] http://the-echoplex.net/csscrush
>> [3]
>> https://github.com/peteboere/css-crush/blob/master/plugins/hocus-pocus.php
>
> Like Brian said, he and I and Boris Zbarsky have been privately
> brainstorming over something like this.
>
> I think it's quite reasonable to have a mechanism to define aliases
> for compound selectors.  This allows for CSS that is easier to read
> and maintain (though I personally don't think that 'hocus' and 'pocus'
> are very good names ^_^).
>
> Something like this, perhaps:
>
> @selector-alias :my-pseudo :matches(:focus, :active);
>
> ~TJ
>
>
Received on Wednesday, 9 November 2011 16:59:33 GMT

This archive was generated by hypermail 2.3.1 : Tuesday, 26 March 2013 17:20:46 GMT