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2018-10-12 15:37:13 -04:00
---
title: Compare Scopes of the var and let Keywords
---
![:triangular_flag_on_post:](https://forum.freecodecamp.com/images/emoji/emoji_one/triangular_flag_on_post.png?v=3 ":triangular_flag_on_post:") Remember to use <a>**`Read-Search-Ask`**</a> if you get stuck. Try to pair program ![:busts_in_silhouette:](https://forum.freecodecamp.com/images/emoji/emoji_one/busts_in_silhouette.png?v=3 ":busts_in_silhouette:") and write your own code ![:pencil:](https://forum.freecodecamp.com/images/emoji/emoji_one/pencil.png?v=3 ":pencil:")
## Problem Explanation:
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Change the code so that the variable `i` declared in the if block is separately scoped than the variable `i` declared at the beginning of the function.
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## ![:speech_balloon:](https://forum.freecodecamp.com/images/emoji/emoji_one/speech_balloon.png?v=3 ":speech_balloon:") Hint: 1
* _Be certain not to use the `var` keyword anywhere in your code._
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> _try to solve the problem now_
* _Remember that `let`'s scope is limited to the block, function or statement in which you declare it._
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> _try to solve the problem now_
## Spoiler Alert!
![warning sign](//discourse-user-assets.s3.amazonaws.com/original/2X/2/2d6c412a50797771301e7ceabd554cef4edcd74d.gif)
**Solution ahead!**
## ![:beginner:](https://forum.freecodecamp.com/images/emoji/emoji_one/beginner.png?v=3 ":beginner:") Basic Code Solution:
```javascript
function checkScope() {
"use strict";
let i = "function scope";
if (true) {
let i = "block scope";
console.log("Block scope i is: ", i);
}
console.log("Function scope i is: ", i);
return i;
}
```
## Code Explanation:
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By using `let` you can declare variables in relation to their scope.
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### Resources
- ["let" - *MDN Javascript reference*](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/let)
- [Rauschmayer, Axel. "Variables and scoping in ECMAScript 6". *2ality.com*, 2015-02-07.](http://2ality.com/2015/02/es6-scoping.html) Accessed 11 Dec 2018.
- [Bos, Wes. "Quick Tip: Use let with for Loops in JavaScript". *wesbos.com*, 16 Aug 2016.](https://wesbos.com/for-of-es6/) Accessed 11 Dec 2018.
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* Add an explanation of your solution.
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