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45 lines
1009 B
45 lines
1009 B
4 years ago
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## No Adults Wanted
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### `filter`
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In JS most of the time, a loop is not needed and specials array methods can help
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doing the heavy work.
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The first one we are going to see is the `filter` array method:
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```js
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let values = [1, 23, 3, 43, 78, 9, 23, 12]
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let isOver20 = (value) => {
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if (value > 20) {
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return true
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}
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}
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let valuesUnder10 = values.filter(isOver20)
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console.log(valuesUnder10) // [23, 43, 78, 23]
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```
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In this case, `values` is an array and the `.filter` method is used to filter
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only those that are over `20`.
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This is achieved by giving `filter` a special function that will return `true`
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if we want to keep this value or not.
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Filtering is the best way to remove elements from an array, when you only need
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to do a selection but not modify them.
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### Instructions
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Create a function `childrenOnly` that takes an array of numbers and returns only
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those that are lower than 18
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**Example:**
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```js
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const result = childrenOnly([12, 11, 23, 44, 10])
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console.log(result) // [12, 11, 10]
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```
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