Re: [WICG/webcomponents] Reference Target: what type should the `referenceTarget` attribute be? (Issue #1093)

alice left a comment (WICG/webcomponents#1093)

Here is an example of that distinction for `htmlFor` in the WebKit codebase (I've removed the referenceTarget logic for clarity):

```cpp
RefPtr<HTMLElement> HTMLLabelElement::control() const
{
    // An empty string value for `for` would cause this to return true
    if (!hasAttributeWithoutSynchronization(forAttr)) {
        for (auto& descendant : descendantsOfType<HTMLElement>(*this)) {
            if (descendant.isLabelable())
                return const_cast<HTMLElement*>(&descendant);
        }
        return nullptr;
    }
    return isConnected() ? elementForAttributeIfLabelable(*this, forAttr) : nullptr;
}
```

This is an implementation of this language in the HTML spec: 

> If the \[for\] attribute is specified and there is an element in the [tree](https://dom.spec.whatwg.org/#concept-tree) whose [ID](https://dom.spec.whatwg.org/#concept-id) is equal to the value of the [for](https://html.spec.whatwg.org/multipage/forms.html#attr-label-for) attribute, and the first such element in [tree order](https://dom.spec.whatwg.org/#concept-tree-order) is a [labelable element](https://html.spec.whatwg.org/multipage/forms.html#category-label), then that element is the [label](https://html.spec.whatwg.org/multipage/forms.html#the-label-element) element's [labeled control](https://html.spec.whatwg.org/multipage/forms.html#labeled-control).
> 
> If the [for](https://html.spec.whatwg.org/multipage/forms.html#attr-label-for) attribute is not specified, but the [label](https://html.spec.whatwg.org/multipage/forms.html#the-label-element) element has a [labelable element](https://html.spec.whatwg.org/multipage/forms.html#category-label) descendant, then the first such descendant in [tree order](https://dom.spec.whatwg.org/#concept-tree-order) is the [label](https://html.spec.whatwg.org/multipage/forms.html#the-label-element) element's [labeled control](https://html.spec.whatwg.org/multipage/forms.html#labeled-control).


-- 
Reply to this email directly or view it on GitHub:
https://github.com/WICG/webcomponents/issues/1093#issuecomment-2677283669
You are receiving this because you are subscribed to this thread.

Message ID: <WICG/webcomponents/issues/1093/2677283669@github.com>