Basic JavaScript - Using Objects for Lookups

Tell us what’s happening:
Hi guys! For result = lookup[val]; at the end, is there a reason why only bracket notation works and not dot notation?

Your code so far

// Setup
function phoneticLookup(val) {
  let result = "";

  // Only change code below this line
 const lookup = {
   "alpha": "Adams",
   "bravo": "Boston",
   "charlie": "Chicago",
   "delta": "Denver",
   "echo": "Easy",
   "foxtrot": "Frank",

result = lookup[val];
  // Only change code above this line
  return result;


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Challenge: Basic JavaScript - Using Objects for Lookups

Link to the challenge:

What is the purpose of using brackets? What do they allow you to do? Maybe an example will help you answer this? What is the difference between




Does using dot notation allow you to make this distinction? If not, which one does dot notation implement? In other words, which of the following is correct:

myObject["value"] == myObject.value


myObject[value] == myObject.value
1 Like

I see. Using dot notation makes it so “value” is a string while bracket defines it better. In other words myObject.value = myObject[“value”] which is not what I’m looking for. Thanks!

1 Like

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