Implement Queue interface using linked list

linked-list-as-queue.js

// linked-list-as-queue

function queue() {
  this.head = null;
}

queue.prototype.print = function() {
  console.log('print');
  let curr = this.head
  while(curr) {
    console.log(curr.val)
    curr = curr.next
  }
}

queue.prototype.push = function(val) {
  console.log('push');
  let curr = this.head;
  
  if (!this.head) {
    this.head = {
      val: val,
      next: null
    }
  } else {  
    while(curr.next) {
      curr = curr.next;
    }
    curr.next = {
      val: val,
      next: null
    }
  }
}

queue.prototype.pull = function() {
  console.log('pull');
  let pulled;
  if (!this.head) {
    pulled = null;
  } else {
    pulled = this.head;
    this.head = this.head.next;
  }
  return pulled;
}


let q = new queue();
q.push(5);
q.push(4);
q.push(3);
q.push(2);
q.push(1);

q.print();

q.pull();
q.print();