Client: Rename a collection's "row" to an "item" and fold content anchor

[marcoroth]

This pull request settles the vocabulary of the slot marker format on one set of words, and reduces the two attributes that anchor a slot to an element down to one.

Nothing outside this stack reads the format yet, which is the only reason this is cheap. Every one of these changes is breaking, and each gets more expensive the longer it waits.

row is table vocabulary, and a collection repeats <li>, cards and <option> as readily as it repeats <tr>. The slot type beside it is already collection, and a collection has items, which is also what Rails calls them when render collection: renders one partial per item.

<!--herb-item:0:42--><li data-herb-slot="1:child">Marco</li><!--/herb-item:0-->

{ 0 => { items: { "42" => { 1 => "Marco" } } } }

slots.itemsFor(file, 0)
slots.slotInItem(file, 0, "42", 2)
slots.updateItem(collection, "42", html)

Also, an element's content slot had an attribute of its own while every other slot on that element was in data-herb-slot, and the index called what the first one produced a content anchor, so the format and the index disagreed about its name.

The anchor kind is a property of the slot's type and does not need an attribute to carry it. child means the value goes inside the element, and every other type on that attribute means the element itself:

-<li id="1" data-herb-slot="1:attribute:id" data-herb-child="2">Marco</li>
+<li id="1" data-herb-slot="1:attribute:id 2:child">Marco</li>

The list is space-separated now, which is what HTML uses for token lists, and it means a slot can be found with a selector instead of by parsing the attribute:

document.querySelectorAll('[data-herb-slot~="2:child"]')

~= matches one token of a whitespace-separated list, so the comma form could not be queried this way. A content-only element grows three characters, an element carrying both roles shrinks by a whole attribute.

Some values of SlotOperation named what kind of thing changed and two named what happened to one item, and rewriting an item's markup fell through to markup with a key set:

-{ operation: "markup", key: "42" }
+{ operation: "item-updated", key: "42" }

markup keeps its meaning for a whole slot rewritten at once, which is the case that carries no key. Nothing read the operation except the Dev Tools flash, which looks it up in a colour map, so this costs one entry there. No test covered that path before, and one does now.

Slots are experimental and the marker format is not stable yet.

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☁️ Nx Cloud last updated this comment at 2026-08-18 12:37:46 UTC

[github-actions]

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commit: 2200b03