export function throttle(func: () => void, limit: number) {
  let timer: any = null;
  return function () {
    if (!timer) {
      timer = setTimeout(() => {
        func();
        timer = null;
      }, limit);
    }
  };
}

// race for promises returns first promise that resolves
export function race<T>(promises: Promise<T>[]): Promise<T> {
  return new Promise((resolve, reject) => {
    for (const p of promises) {
      p.then(resolve, reject);
    }
  });
}

export function timeout(ms: number): Promise<never> {
  return new Promise((_resolve, reject) =>
    setTimeout(() => {
      reject(new Error("timeout"));
    }, ms)
  );
}

export function sleep(ms: number): Promise<void> {
  return new Promise((resolve) => setTimeout(resolve, ms));
}