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JavaScript JavaScript Loops, Arrays and Objects Simplify Repetitive Tasks with Loops Refactor Using a Loop

Joy Faber
Joy Faber
3,843 Points
Posted by Joy Faber
Joy Faber
3,843 Points

There was an error with your code: ReferenceError: Strict mode forbids implicit creation of global property 'j'

ik keep getting this error and dont know what it means. while my code is 100% correct.

script.js 
for ( j = 2 ; j <= 24; j +=2)
{
console.log(j);
}
index.html 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript Loops</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>
Usman Badar
Usman Badar
9,304 Points

Please declare data type of j in the start of the for loop such as var.

1 Answer

Zimri Leijen
Zimri Leijen
11,719 Points
Zimri Leijen
Zimri Leijen
11,719 Points 
for (let j = 2 ; j <= 24; j +=2)
{
console.log(j);
}

since you're not explicitly declaring j (using let or var) it's throwing errors.

Joy Faber
Joy Faber
3,843 Points
Joy Faber
Joy Faber
3,843 Points

ah... got it thanks