Lattish - Runtime for Tish JSX

h

Creates DOM elements or renders components.

// Element
h("div", { class: "container" }, [h("p", {}, ["Hello"])])
 
// Component (function)
h(Greeting, { name: "World" }, [])

When the first argument is a function, it's called as a component with props (including children if provided).

Fragment

Groups children without a wrapper element.

h(Fragment, {}, [child1, child2, child3])

In JSX: <><Child1 /><Child2 /></>

text

Returns a string for text nodes. The compiler uses this for interpolated text.

createRoot

Mounts a component and handles re-renders.

let root = createRoot(document.getElementById("root"))
root.render(App)

After render, Lattish will re-render whenever component state changes (via useState, etc.).

Custom host (non-DOM targets)

createRoot takes an optional second argument — a host config — so the same hooks and reconciler can drive a target other than the DOM (a terminal, a canvas, a test shadow tree). Omit it and Lattish uses the built-in DOM host unchanged.

createRoot(container, host).render(App)

A host is a plain object implementing the node operations the reconciler calls. The shape mirrors react-reconciler's host config:

Method	Purpose
`createElement(tag)`	create an element node for `tag`
`createText(value)`	create a text node
`createComment()`	create a comment/placeholder node
`createFragment()`	create a fragment container
`isText(node)`	is this a text node?
`setText(node, value)`	update a text node's value in place
`appendChild(parent, child)`	append `child` to `parent`
`removeChild(parent, child)`	remove `child` from `parent`
`replaceChild(parent, newChild, oldChild)`	replace `oldChild` with `newChild`
`replaceChildren(parent, nodes)`	replace all of `parent`'s children with `nodes`
`childAt(parent, i)`	the child at index `i`
`firstChild(parent)`	the first child of `parent`
`mountProp(el, tag, key, value)`	apply a prop on first mount
`patchProp(el, tag, key, value, prev)`	update a prop on re-render
`styleRemoved(el)`	a `style` prop was removed — clear it
`setRef(refObj, value)`	assign a ref (`refObj.current = value`)

Each root remembers its own host, so DOM roots and custom-host roots can coexist in one app.

Lattish 2.0 is built on the tish 2.0 toolchain (@tishlang/tish ^2.0.0).