how to use the flatmapdepth function from lodash in javascript

The flatMapDepth method in lodash is used to recursively flatten an array up to the specified depth. Here's an example of its usage:

index.tsx
const _ = require('lodash');

const myNestedArray = [1, 2, [3, [4, 5]]];
const flattenedArray = _.flatMapDepth(myNestedArray, value => {
  if (Array.isArray(value)) {
    return value.map(nestedValue => nestedValue * 2);
  } else {
    return value * 2;
  }
}, 1);

console.log(flattenedArray); // Output: [ 2, 4, 6, [ 8, 10 ] ]
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In the above code, we first import lodash using the require statement. We then define myNestedArray, which is a sample nested array. We then call the flatMapDepth method on this array, passing in a callback function as the second argument. This callback function checks if a value is an array, and if it is, it returns a new array that doubles each value in that array. If the value is not an array, it doubles the value itself.

Finally, we pass the value of 1 as the third argument to flatMapDepth, indicating that we want to flatten the array only up to a depth of 1. The output of this code is the flattened array [ 2, 4, 6, [ 8, 10 ] ].