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JavaScript JavaScript Loops, Arrays and Objects Tracking Data Using Objects Accessing All of the Properties in an Object

Alexandru Vlasnita
Alexandru Vlasnita
5,542 Points
Posted by Alexandru Vlasnita
Alexandru Vlasnita
5,542 Points

Is it me or is it broken?

Whatever name i give it to the property, it sends me this error

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

script.js 
var shanghai = {
  population: 14.35e6,
  longitude: '31.2000 N',
  latitude: '121.5000 E',
  country: 'CHN'
};

for (prop in shanghai) {
  console.log(prop);
}
index.html 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript Objects</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>

1 Answer

Steven Parker
Steven Parker
231,275 Points
Steven Parker
Steven Parker
231,275 Points

The challenge interpreter is running in "strict" mode, where implicit declarations are not allowed. So your loop needs to include an explicit declaration (either "var" or "let"):

for (var prop in shanghai) {
Alexandru Vlasnita
Alexandru Vlasnita
5,542 Points
Alexandru Vlasnita
Alexandru Vlasnita
5,542 Points

Oh yea, really forgot about the variable part