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JavaScript JavaScript Objects Loop Through Objects Useful JavaScript Object Methods

Posted by Aiden Turner
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Aiden Turner
Web Development Techdegree Student 5,644 Points

Get error with sample code in Firefox's console

I got an error message (Uncaught SyntaxError: redeclaration of const person) when inserting the following code into Firefox's console. The code works fine in Chrome. 

const person = {
  name: 'Reggie',
  role: 'Software developer',
  skills: ['JavaScript', 'HTML', 'CSS'],
  isTeacher: true
};

for ( let prop in person ) {
  console.log(prop);
}

1 Answer

Jonathan Grieve
MOD
Jonathan Grieve
Treehouse Moderator 91,252 Points
Jonathan Grieve
Jonathan Grieve
Treehouse Moderator 91,252 Points

Try removing the let keyword keyword from your working variable.

It could be that Firefox doesn't like that you're trying to do something with the person once it's declared as a constant and then as a let. Constant variable values can't be changed again in a script. Technically the value isn't being changed here but it could be causing that as an issue.