Implement :nth-child(An+B of selector list)

[BenjaminPoulain]

WebKit has support for CSS4's :nth-child(An+B of selector list). It would be great if sizzle could add the pseudo class to simplify backward compatibility.

The specification is here: http://dev.w3.org/csswg/selectors/#the-nth-child-pseudo
My implementation feedback to W3C: http://lists.w3.org/Archives/Public/www-style/2014Oct/0106.html
The tests of WebKit are here: http://trac.webkit.org/browser/trunk/LayoutTests/fast/selectors/ (all the tests starting with nth-child-of. The most useful outside WebKit are nth-child-of-basics.html and nth-child-of-basics-2.html).

[gibson042]

This is a public copy of the editors’ draft. It is provided for discussion only and may change at any moment. Its publication here does not imply endorsement of its contents by W3C. Don’t cite this document other than as work in progress.

Thanks. Unfortunately, we cannot yet include CSS4 selectors in a release, but will happily consider code if you have a particular implementation in mind. Otherwise, I wouldn't expect anything here until after the spec makes it to Recommendation status.

[gibson042]

Specifically, though, I've been considering making a CSS4 branch to test the cost of new selectors so they're ready to go on day 1. We'll probably add it when we ship Sizzle 3.0.0 later this year.

[mgol]

@gibson042 Did you mean Sizzle 3.0? 2.0 is already on npm. ;)

[gibson042]

Yes, it was a mistranslation of "next major release". Fixed.

[timmywil]

Duplicate of #237