Duplicate array

by sramnan

JavaScript

console.log(typeof(undefined));
console.log(typeof(null));
var arr= [1,2,3,4,5];

function dup(arr){
return (arr.concat(arr));
}
var newArr = dup(arr);
console.log(newArr);
console.log('one');
setTimeout(function() {
  console.log('two');
}, 0);
console.log('three');
var test = '\d+';