[selectors] “any <a> or <area> elements are hyperlinks” is incorrect

[simevidas]

I think this information is not entirely correct:

For example, in HTML5, any <a> or <area> elements are hyperlinks, and thus match :any-link.

Link to section: https://drafts.csswg.org/selectors/#the-any-link-pseudo

According to the HTML Standard, the <a> and <area> elements are only then hyperlinks if they have an href attribute.

If the <a> element has an href attribute, then it represents a hyperlink (a hypertext anchor) labeled by its contents. If the <a> element has no href attribute, then the element represents a placeholder…

Source: https://html.spec.whatwg.org/multipage/text-level-semantics.html#the-a-element

Browsers follow this definition. In browsers, the :any-link selector matches <a href="#">foo</a> but not <a>foo</a>. Therefore, the CSS spec should say “any <a> or <area> elements with href attributes are hyperlinks”.

[tigt]

This may fall under “specifications of the host language”, but for backwards compatibility reasons, a[xlink|href] in the SVG namespace also matches :any-link. (This applies to SVG-in-HTML5 and also SVG-as-XML, where the XLink namespace can be bound to any prefix, not just xlink:.)

[ByteEater-pl]

More precisely, an a or area element with a href attribute is a source of a hyperlink and the resource or resource fragment identified in href is the target – a link cannot exist without both (or more than two – XLink allows that). And although HTML5 drops the mention that a without href may be used to mark up the target, it neither forbids it, nor offers an alternative (fortunately), so it IMO remains advisable.

Incidentally, the above also suggests that :any-link shouldn't match if the value of href is syntactically invalid per RFC 3986.

[simevidas]

although HTML5 drops the mention that a without href may be used to mark up the target, it neither forbids it, nor offers an alternative

Isn’t the id attribute the standard way to mark up link targets?

[ByteEater-pl]

Yes! But on what element? If there is already an element encompassing exactly the fragment you want to link to, probably adding an a around it would be overkill in most cases. But if not, what do you use? There is the generic block-level container div and the generic inline-level container span, so they could say: use one of those, depending on how you want it treated, if the contents are all inline-level, and always div otherwise. But that's both a more complex set of guidelines and overloading div and span with yet more semantic roles, whereas a hrefless a is already perfect for the job and specified to fulfill it in earlier versions and other branches of (X)HTML. So I stick to it and hope others will too.

[simevidas]

@ByteEater-pl The id attribute is already allowed on all elements, and websites are using different elements as link targets (e.g., headings, <main>). This is going to stay that way because limiting link target functionality to href-less <a> would break the web.

[ByteEater-pl]

Oh, no, that I definitely don't propose. Linking to arbitrary elements by their ID has always worked and it's fine, shouldn't be changed. What I described is a situation where there's no element already at the target, just some range of a document, and the author is wondering what to wrap around it to enable having an attribute of type ID (of which there's just one in HTML: id).

[fantasai]

Just noticed this while reviewing changes in preparation for republication. :) This was previously correct, but was broken in 0ea038e ; it's now fixed in 887dbb3

Thanks for noticing!