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Partially reformat for loop post

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Chalarangelo
2021-09-28 19:30:27 +03:00
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blog_posts/javascript-for-in-for-of-foreach.md
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@ -9,8 +9,7 @@ firstSeen: 2020-01-20T10:12:31+02:00
lastUpdated: 2021-06-12T19:30:41+03:00
---
`for...in` is used to iterate over all enumerable properties of an object, including inherited enumerable properties.
This iteration statement can be used with arrays strings or plain objects, but not with `Map` or `Set` objects.
`for...in` is used to iterate over all enumerable properties of an object, including inherited enumerable properties. This iteration statement can be used with arrays strings or plain objects, but not with `Map` or `Set` objects.
```js
for (let prop in ['a', 'b', 'c'])
@ -26,8 +25,7 @@ for (let prop in new Set(['a', 'b', 'a', 'd']))
console.log(prop); // undefined (no enumerable properties)
```
`for...of` is used to iterate over iterable objects, iterating over their values instead of their properties.
This iteration statement can be used with arrays, strings, `Map` or `Set` objects, but not with plain objects.
`for...of` is used to iterate over iterable objects, iterating over their values instead of their properties. This iteration statement can be used with arrays, strings, `Map` or `Set` objects, but not with plain objects.
```js
for (let val of ['a', 'b', 'c'])
@ -43,8 +41,7 @@ for (let val of new Set(['a', 'b', 'a', 'd']))
console.log(val); // a, b, d (Set values)
```
Finally, `forEach()` is a method of the `Array` prototype, which allows you to iterate over the elements of an array.
While `forEach()` only iterates over arrays, it can access both the value and the index of each element while iterating.
Finally, `forEach()` is a method of the `Array` prototype, which allows you to iterate over the elements of an array. While `forEach()` only iterates over arrays, it can access both the value and the index of each element while iterating.
```js
['a', 'b', 'c'].forEach(