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JavaScript React Basics (retired) Thinking in Components Properties Review

Greg Kaleka
Greg Kaleka
39,019 Points

React.js required string - bug or am I doing something wrong?

I kinda think I'm right, but it's entirely possible I'm doing something wrong. Is it the trailing comma that's throwing the challenge for a loop?

quiz screenshot

2 Answers

Dale Severude
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Dale Severude
Full Stack JavaScript Techdegree Graduate 71,324 Points

Yes, drop the comma and the challenge will pass. The last key-value pair shouldn't have a comma, but if there are any previous key value pairs, they do require a comma.

Greg Kaleka
Greg Kaleka
39,019 Points

Thanks Dale. I did get it to pass by removing the comma.

In modern js, it's actually a best practice to have a trailing comma. This is similar to other languages like Python. It makes things go more smoothly if you need to add, delete, or re-arrange the elements in an object, array, etc.

If you watch the videos, you'll see that Jim follows this best practice without fail. I'm going to go ahead and report the bug.