Typewriting style pre-populate

typer.js

/*
 * Input populate with typerwriting emulation (sort of...)
 * (e.g. for url like /[email protected])
 */

var email = "[email protected]", // e.g. get email from url query params
    input = document.querySelector('input[name="email"]'),
    splitted = email.split(''),
    type;

function _preventDefault(e){
  e.preventDefault();
}

input.addEventListener('keypress', _preventDefault);
input.addEventListener('focus', function(){
  input.removeEventListener('keypress', _preventDefault);
});

type = window.setInterval(function(){
  if(!splitted.length) {
    window.clearInterval(type);
    input.focus();
  } else {
    shifted = splitted.shift();
    input.value += shifted;
  }
}, 50);