linked list using JS, simple

linkedList.js

var node = function (value){
  this.value = value;
  this.next = null;
  return this;
}

var list = function (){
  this.head = null;
  return this;
}

list.prototype.last = function (){
  var c = this.head;
  while(c&&c.next){
    c = c.next;
  }
  return c;
};

list.prototype.push = function(value){
  var n = new node(value);
  if(!!this.last()) {
    this.last().next = n;
  } else {
    this.head = n;
  }
  return this;
};

list.prototype.print = function (){
  var c = this.head;
  while(c){
    console.log(c.value);
    c = c.next;
  }
  return true;
};

list.prototype.length = function (){
  var l = 0,c = this.head;
  while(c){
    c = c.next;l++;
  }
  return l;
};

//---- TEST ----
ll.push(5).push(7);
ll.push(4);
ll.last();
ll.print();