Linked List Implementation with Javascript

class Node {
  constructor(val) {
    this.val = val;
    this.next = null;
  }
}

let countNodes = (node) => {
  let count = 0;
  let head = node;
  while (head.next !== null) {
    head = head.next;
    count = count + 1;
  }
  return count;
};

let pushFront = (ele, list) => {
  let newNode = new Node(ele);
  newNode.next = list;
  return newNode;
};

let pushAtElement = (newEle, target, list) => {
  let head = list;
  let prev;
  let newNode = new Node(newEle);
  while (head.next !== null) {
    if (head.val === target) {
      prev = head;
      break;
    }
    head = head.next;
  }

  newNode.next = prev.next;
  prev.next = newNode;
  return list;
};

let pushAtEnd = (newEle, list) => {
  let newNode = new Node(newEle);
  if (list === null) {
    list = newNode;
    return list;
  }
  let head = list;
  let prev;
  while (head.next !== null) {
    prev = head;
    head = head.next;
  }
  newNode.next = prev.next;
  prev.next = newNode;
};

let deleteAtFront = (list) => {
  let tmp = list;
  list = tmp.next;
  return list;
};

let deleteAtEnd = (list) => {
  let head = list;
  let prev;
  while (head.next !== null) {
    prev = head;
    head = head.next;
  }
  prev.next = null;

  return list;
};

let deleteAtElement = (ele, list) => {
  let prev;
  let head = list;
  while (head.next !== null) {
    if (head.val === ele) {
      prev = head;
      if (prev.next) {
        let rest = prev.next.next;
        prev.next = rest;
      } else {
        prev.next = null;
      }
      break;
    }
    head = head.next;
  }
  return list;
};