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JavaScript React Basics (retired) Stateful Components Creating a Component Class

Posted by Alexander Davison
Alexander Davison
65,469 Points

Weird syntax (React.js)

Why does Jim put a comma on the last element of an object? Also, why doesn't it cause errors?

Thanks in advance! ~Alex

2 Answers

Jennifer Nordell
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STAFF
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher
Jennifer Nordell
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher

I've seen others do this as well, and no it doesn't cause an error. But I believe the reason to do it is to easily allow yourself to quickly add a new property or method to an object without introducing a syntax error. This way you don't have to remember to add a comma to your last thing in the object before you start typing the new one. I'm fairly sure Alena does it in one of her PHP courses as well, but can't find it right now. Hope this helps! :sparkles:

Alexander Davison
Alexander Davison
65,469 Points

Thank you for explaining! :)

Francis N
Francis N
10,376 Points
Francis N
Francis N
10,376 Points

Yes I kind of like that you can add/keep the commas there without throwing an error like you usually would see happen in ES5. Although, I was a little confused for a second at first because it wasn't mentioned in the video.