Create a context-free function that dispatches values to a subscriber context

01-signal.ts

import { createChannel, run, type Stream } from "./mod.ts";

export function createSignal<T>(): [(event: T) => void, Stream<T, never>] {
  let { input, output } = createChannel<T, never>();

  let pulse = (event: T) => run(() => input.send(event));

  return [pulse, output];
}

02-onclick.ts

export function onclick(element: HTMLElement): Stream<MouseEvent, never> {
  let [onClick, receiver] = createSignal<MouseEvent>();
  return resource(function* (provide) {
    try {
      element.addEventlistener("click", onClick);
      let subscription = yield* receiver;
      yield* provide(subscription);
    } finally {
      element.removeEventListener("click", onClick);
    }
  });
}