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

To use the negate function from the underscore library in TypeScript, you need to first import the negate function from the underscore library.

Here's an example:

index.ts
import { negate } from 'underscore';

const isEven = (num: number) => num % 2 === 0;

const isOdd = negate(isEven);

console.log(isOdd(3)); // true
console.log(isOdd(4)); // false
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In this example, we first define a function called isEven that checks whether a number is even or not. We then use the negate function to create a new function called isOdd, which returns the opposite of isEven. Finally, we test the isOdd function by passing it some numbers and logging the results to the console.

The negate function takes a function as an argument and returns a new function that, when called, returns the opposite value of the original function. In this case, isOdd returns true if a number is odd and false if it is even.