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

To use the range function from the underscore library in TypeScript, you first need to install underscore via npm (Node.js package manager) using the following command in your terminal:

index.ts
npm install underscore
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Once you have installed the underscore library, you can import it and use the range function as shown in the code snippet below:

index.ts
import * as _ from 'underscore';

const rangeArr: number[] = _.range(1, 10, 2); // returns [1, 3, 5, 7, 9]
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The range() function takes three arguments:

• start (optional): The starting value for the range. Default is 0.
• stop: The ending value for the range (exclusive).
• step (optional): The step value for increments in the range. Default is 1.

In the example above, we imported underscore as a namespace (import * as _ from 'underscore'). We then called the _.range(1, 10, 2) function to create an array of odd numbers from 1 to 9 (inclusive).

Note that in TypeScript, we explicitly specify that the type of the variable rangeArr is an array of numbers (number[]).