Debounce function implemented in ES6

debounce.js

// As long as it continues to be invoked, the callback will not be triggered.
// The function will be called after it stops being called for N milliseconds. 
const debounce = (callback, wait) => {
  // there is no timeout by default
  let timeout = null

  return function(...args) {
    // last timeout is cleared every time after first call 
    clearTimeout(timeout)
    // callback will only be fired if it was not cleared by invocation occuring before N milliseconds
    timeout = setTimeout(() => callback.apply(this, args), wait)
  }
}