Discussion on: 5 things that might surprise a JavaScript beginner/ OO Developer

[willparr]

In the section about block scope, I found it interesting that you explained it like this:

Block statements, if, for, while etc, don't create a local scope.

Is there a reason that you decided to explain it that way? Compared to explaining that var doesn't adhere to local scope and let does? I just thought it might give more clarity that it's the variables rather than the actual blocks that are concerned with scope.

I really enjoyed how you explained the this issue that people run into when learning JS. It is extremely common and the solutions you gave are spot on! I remember banging my head against the wall trying to understand it!

[Chris Noring]

hey Will.. I've seen many articles referring it as if, for, while, doesn't create a new scope but function does, here for example scotch.io/tutorials/understanding-.... I mean I totally see your way as well, especially with MDN saying this about let, let allows you to declare variables that are limited to the scope of a block statement. Yea I'll see if I can amend this in a good way, appreciate the comment :)

[maowtm]

You should probably also mention that

for (let i = 1; i <= 3; i ++) setTimeout(() => console.log(i), 100);

gets you 1 2 3, whereas

for (var i = 1; i <= 3; i ++) setTimeout(() => console.log(i), 100);

will output 4 4 4. IMO this is one of the major reason why scope of loop variable matters.