Re: [selectors] Proposal: :only-of(selector list)

On 11/11/14 4:14 PM, Tab Atkins Jr. wrote:
> On Mon, Nov 10, 2014 at 8:40 PM, Benjamin Poulain <bpoulain@apple.com> wrote:
>> It looks like it would be useful to include :only-of(selector list) in Selectors Level 4.
>>
>> It is already possible to achieve the same behavior by using :nth-child(1 of selector list):nth-last-child(1 of selector list) but that is significantly uglier. Repeating the selector list is error prone when updating the stylesheet and the specificity is doubled.
>>
>> The selector :only-of(selector list) would behave like :nth-child(1 of selector list):nth-last-child(1 of selector list) but with lower specificity (accounting for the selector list once instead of duplicating it). The definition of :only-of-type is pretty much the same.
>>
>> The implementation is trivial based on the existing :nth-child() and :nth-last-child(). The single :only-of() is likely to be more efficient than :nth-child():nth-last-child() in most implementations.
>
> Do you have some use-cases to share that would use this?

Pretty much the same uses use cases of :only-of-type and :only-child 
exists for :only-of.

Many designs are based on classes or data attributes. Having 
:only-of-type does not help in those cases.

Benjamin

Received on Thursday, 13 November 2014 04:33:57 UTC