Given a function fn and a time in milliseconds t, return a throttled version of that function.

throttle.js

/*
A throttled function is first called without delay and then, for a time interval of t milliseconds, can't be executed but should store the latest function arguments provided to call fn with them after the end of the delay. 
*/

const throttle = function (fn , t){
  let intervalInProgress = null; 
  let argsToProcess = null; 
  
const intervalFunction = () =>{
  if(argsToProcess == null){
    clearInterval(intervalInProgress);
intervalInProgress = null; 
  }
else {
  fn(...argsToProcess);
  argsToProcess = null;
}}
  return function(...args) {
if(intervalInProgress){
  argsToProcess = args;
}
else{
  fn(...args);
  intervalInProgress = setInterval(intervalFunction , t);
}
  }
};