debounce function

debounce.js

const btn = document.querySelector('.btn');

function debounce (fn, delay) {
  let timeout;
  return function(){
    if (timeout){
      clearTimeout(timeout);
    }
    timeout = setTimeout(()=>{
       fn()
    },delay);
  }
};

btn.addEventListener('click', debounce(()=>{
  console.log('click');
},2000))