
Andy Poulton
UX Design Techdegree Student 6,541 PointsReference Error on For In Loop Code Challenge
So I keep getting this error even though the code works outside of treehouse.
Bummer: There was an error with your code: ReferenceError: Strict mode forbids implicit creation of global property 'prop'
I'm probably missing something small, but this is driving me nuts.
var shanghai = {
population: 14.35e6,
longitude: '31.2000 N',
latitude: '121.5000 E',
country: 'CHN'
};
for (prop in shanghai){
console.log(prop);
};
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>JavaScript Objects</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>
1 Answer

Sylvester Hofstra
12,020 PointsYou forgot to declare the variable within the 'for... in'-loop:
var shanghai = {
population: 14.35e6,
longitude: '31.2000 N',
latitude: '121.5000 E',
country: 'CHN'
};
for (const prop in shanghai){
console.log(prop);
};