01-types.ts

export interface HeartbeatAction {
  type: "heartbeat";
  count: number;
}

02-producer.ts

/**
* Consistently produce a heartbeat reliably every 500ms
*/
export function* produce() {
  let count = 1;
  while (true) {
    yield* sleep(500);
    yield* put({type: "heartbeat", count });
  }
}

03-consumer.ts

/**
* Takes a heart beat, and then simulates some asynchronous "work" that takes anywhere from 
* 0 to 1000ms. It is deliberately out of phase with the producer so that there will be times
* when a heartbeat is generated that this is not yielded in `take()`
*/
function* consume() {
  while (true) {
    let beat: HeartbeatAction = yield* take({type: "heartbeat"});
    yield* sleep(Math.random() * 100);
    console.log(`beat ${beat.count}`);
  }
}