how to use the flatmap function from lodash in javascript

The flatMap function from Lodash is a powerful tool to transform arrays. It allows you to map over an array, and then flatten the resulting mapped values into a single array. Here's how to use it in JavaScript:

First, install lodash using the following command:

npm install lodash
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Then, require it in your code:

index.tsx
const _ = require('lodash');
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Now, you can use the flatMap function as follows:

index.tsx
const arr = [1, 2, 3];
const mappedArr = _.flatMap(arr, (num) => [num, num * 2]);
console.log(mappedArr); // [1, 2, 2, 4, 3, 6]
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In this example, we create an array arr with the values [1, 2, 3]. We then use flatMap to map over each value in the array and return a new array with twice the value. By returning an array in the mapping function, the result of each iterator is flattened into a single array.

The resulting array mappedArr is [1, 2, 2, 4, 3, 6], which is the original array with each element doubled.

And that's how you can use the flatMap function from Lodash in JavaScript.