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JavaScript Create an Object Literal

Posted by Dmytro Stoianov
Dmytro Stoianov
6,647 Points

var word in the" for in " loop

Hello Everyone. Could You please explain to my why we don't use a var keyword inside a for in loop. This is the second time I've seen it in the video, but the previous one was marked as incorrect. So how should we use a variable in a "for in" loop?

1 Answer

Adam N
Adam N
70,280 Points
Adam N
Adam N
70,280 Points

Do you mean:

for (var item in items) {

If so, you're supposed to use var/let in the for-in, but it'll still work without it.

Let me know if this helps here

Dmytro Stoianov
Dmytro Stoianov
6,647 Points

Yes, this is exactly what I meant. I'm just curious: what is the purpose of using it if it works without it? Is it just easier to read it like this for others who may use my code?

Adam N
Adam N
70,280 Points

JS by default is just not that strict of a language. For example, most of the time you dont need to end statements with a semicolon.

If you run your JS in strict mode, it will produce an error in this for-in loop situation if the var keyword is left out. There's a workshop on strict here https://teamtreehouse.com/library/the-javascript-use-strict-statement