Javascript Array append(ar)

Array.prototype.append = function(ar) {
  this.length += ar.length;
  for (var i = 0, len = this.length, len2 = ar.length; i < len2; i++) {
    this[len + i] = ar[i];//ww w .j a v a  2 s.  co  m
  }
};

Array.prototype.append = function(array)
{
  this.push.apply(this, array)/*from   www  . j ava  2s.c  om*/
}

function print(s) {
  console.log(s);/*from  w  w w .j  a v  a2 s  . c o m*/
}

function println(s) {
  console.log(s);
}

Array.prototype.append = function(e) {
  this.push(e);
}

Array.prototype.append = function(item) {
 for (let i = 0; i !== this.length; i++) {
  if (this[i] === null || this[i] === undefined) {
   this[i] = item;//w w  w.ja  v  a2s.  c  om
   return i;
  }
 }
 return this.push(item) - 1;
};