Customized Linked Lists with Javascript

myLinkedLists.js

// From ThatJSDude

function linkedList () {
  this.head = null
  this.length = 0
}

linkedList.prototype.push = function (val) {
  var node = {
    value: val,
    next: null
  }
  
  if (!this.head) {
    this.head = node
    this.length++;
  } else {
    var current = this.head
    while (current.next) {
      current = current.next
    }
    
    current.next = node
    this.length++;
  }
  
}

linkedList.prototype.removeNode = function (position) {
  var currentNode = this.head,
      length = this.length,
      count = 0,
      message = {failue: 'Failure: non-existent node in this list.'},
      beforeNodeToDelete = null,
      nodeToDelete = null,
      deletedNode = null;
  
  if (position < 0 || position > this.length) {
    throw new Error(message.failure)
  }
  
  if (position === 1) {
    this.head = currentNode.next
    deletedNode = currentNode
    currentNode = null
    this.length--
    
    return deletedNode
  }
  
  while (count < position) {
    beforeNodeToDelete = currentNode
    nodeToDelete = currentNode.next
    count++
  }
  
  beforeNodeToDelete.next = nodeToDelete
  deletedNode = nodeToDelete
  nodeToDelete = null
  this.length--
  
  return deletedNode
}

linkedList.prototype.searchAt = function (position) {
  var currentNode = this.head,
      count = 1,
      message = {failure: 'Failure: non-existent node in this list.'};
  
  if (this.length === 0 || position < 1 || position > this.length) {
//     console.log("Error occurred.");
    throw new Error(message.failure);
  }
  
  while (count < position) {
    currentNode = currentNode.next
    count++
  }
  
  console.log(currentNode.value);
  
  return currentNode;
}

var myLinkedList = new linkedList()

myLinkedList.push("ABCD")
myLinkedList.push("1234")

console.log(myLinkedList.removeNode(1).value)

// myLinkedList.searchAt(2)

// console.log(myLinkedList.head)
// console.log(myLinkedList.head.next)