JavaScript throttle and debounce arrow functions

throttle-debounce-utils.js

const throttle = (func, delay) => {
  let timeoutId;
  return (...args) => {
    if (!timeoutId) {
      timeoutId = setTimeout(() => {
        func.apply(this, args);
        timeoutId = null;
      }, delay);
    }
  };
};

const debounce = (func, delay) => {
  let timeoutId;
  return (...args) => {
    clearTimeout(timeoutId);
    timeoutId = setTimeout(() => {
      func.apply(this, args);
    }, delay);
  };
};