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JavaScript JavaScript Foundations Functions Return Values

Eric Vandenberg
Eric Vandenberg
9,095 Points

Stuck in JavaScript challenge

Around line 17, create a function named 'arrayCounter' that takes in a parameter which is an array. The function must return the length of an array passed in or 0 if a 'string', 'number' or 'undefined' value is passed in.

This is what I was trying to submit...any suggestions? Thanks!

function arrayCounter (value) {
  if (typeof value === ('string', 'number', 'undefined') {
    return 0;
    }
  else {
    return value.length;
  }
}

2 Answers

Dave McFarland
STAFF
Dave McFarland
Treehouse Teacher

HI Eric Vandenberg

You can't test all 3 values at the same time. You need to run separate tests for each:

if (typeof value === 'string') {
  return 0;
} else if (typeof value === 'number') {
  return 0;
} else if (typeofvalue === 'undefined') {
  return 0;
} else {
  return value.length;
}
Eric Vandenberg
Eric Vandenberg
9,095 Points

Good to know! Thanks for your help Dave