aggregate.ts

function aggregate<T>(f: (ts: T[]) => void, wait: number): (t: T) => void {
  let lastFiredAt = new Date();
  let stack: T[] = [];
  return (t: T): void => {
    stack.push(t);
    const calledAt = new Date();
    const elapsed = calledAt.getTime() - lastFiredAt.getTime();
    if (elapsed >= wait) {
      f(stack);
      stack = [];
      lastFiredAt = calledAt;
    }
  };
}