how to use the difference function from the underscore library in typescript

To use the difference function from the Underscore library in TypeScript, first, we need to install the Underscore library using npm:

index.ts
npm install underscore
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Then, we can import the library in our TypeScript file as follows:

index.ts
import * as _ from "underscore";
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Now, we can use the _.difference method to find the difference between two arrays. The method takes two or more arguments, where the first array is the source array and the remaining arguments are the arrays you want to find the difference of. Here's an example:

index.ts
const originalArray: number[] = [1, 2, 3, 4, 5];
const diffArray: number[] = _.difference(originalArray, [2, 4, 6]);

console.log(diffArray); // Output: [1, 3, 5]
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In the above example, we imported the underscore library, defined an array called originalArray with the initial values, and found the difference between originalArray and another array [2, 4, 6] using the _.difference method. The result, [1, 3, 5], is assigned to diffArray, which is then logged to the console.

Note that the difference function returns a new array with unique values, so if the original array contains duplicate values that are not in the compared arrays, they will be kept in the result.