Function on

source/WebCell.tsx:183–199

(
    type: DelegatedEvent['type'],
    selector: string
)

 * Method decorator of DOM Event delegation
 */
export function on<T extends HTMLElement>(
    type: DelegatedEvent['type'],
    selector: string
) {
    return (
        method: DelegateEventHandler,
        { addInitializer }: ClassMethodDecoratorContext<T>
    ) =>
        addInitializer(function () {
            const events = eventMap.get(this) || [],
                handler = delegate(selector, method.bind(this));

            events.push({ type, selector, handler });

            eventMap.set(this, events);
        });
}