[dot-notation causes errors in this challenge.] Iterate Through the Keys of an Object with a for...in Statement

Tell us what’s happening:
why dot-notation causes errors in this challenge.

Your code so far

let users = {
  Alan: {
    age: 27,
    online: false
  Jeff: {
    age: 32,
    online: true
  Sarah: {
    age: 48,
    online: false
  Ryan: {
    age: 19,
    online: true

function countOnline(obj) {
  // change code below this line

  // change code above this line


Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36.

Link to the challenge:

What error are you getting? What is your code?

I will guess, and suggest this reading

Bracket notation can use variables, so it is useful in two instances where dot notation will not work:

  1. When the property names are dynamically determined (when the exact names are not known until runtime).

  2. When using a for…in loop to go through all the properties of an object.

this thread is over a year old, maybe try helping people that have asked for help in the last week or so?
probably after a year they do not need help anymore