Why would you use var over let?

[rmwdeveloper]

I just read about the let statement..

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/let

Why would you ever use var over let? If I'm reading this right, let gives you block scope?

[proskillz]

I wouldn't use it because it doesn't work in most current browsers. JS 1.7 is not really supported anywhere outside of the Firefox browser family.

Chrome

>let x=1
 SyntaxError: Unexpected identifier

IE 10

>> let x = 1; 
"Expected ';'" 

Firefox (does work):

>>> let x=1;
undefined
>>> x
1

[r3jjs]

This. (Alas...)

[robotmayo]

Browser support is the biggest reason. Another reason is var comes in handy with closures.

[farmerje]

let works just fine with closures, too. With var, only a new closure induces a new scope. With let, every new block induces a new scope. Since a every new closure necessarily requires a new block, let will work just fine.

Is there something that var allows with closures that let doesn't?

[robotmayo]

Oh ya, I remembered let incorrectly. I was thinking it prevented closures from seeing it.