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                <script type=module>
	const gensym = (() => {
		let n = 0;
		return () => `generated-symbol-${n++}`;
	function ensureId(elm) {
		if(! { = gensym();
	function wire(elm, attr, elms) {
		const ids = =>' ');
		if(ids) {
			elm.setAttribute(attr, ids);
	window.customElements.define('input-set', class InputSet extends HTMLElement {
		connectedCallback() {
			// grab first of any kind of element that can be the target
			// should include stuff like select and custom form elements etc.
			const input = this.querySelector('input');

			// collect and wire labels
			const bin = {
				'label': [],
				'description': [],
			this.querySelectorAll('label').forEach(e => {
				if(e.hasAttribute('for')) {
				const k = e.getAttribute('type') || 'label';
				bin[k].push(e); // implicitly ignoring unknown types
			// this would be cleaner if there were input.ariaLabelledbyElements = [] etc.
			wire(input, 'aria-labelledby', bin['label']);
			wire(input, 'aria-describedby', bin['description']);

			// if there's a datalist, wire that up, too
			// this would be cleaner if there were an input.listElement = dl
			const dl = this.querySelector('datalist');
			if(dl && !input.hasAttribute('list')) {
	<label type=description>description</label>
		<option value=A>
		<option value=B>