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

In order to use the negate function from the lodash library in TypeScript, you need to install the library first, following these steps:

1. Open a terminal window and navigate to your project's root directory.
2. Run the following command to install lodash:

npm install lodash
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This will install the lodash library and its dependencies in your project.

3. Next, import the negate function from the lodash library in your TypeScript file:

index.ts
import { negate } from 'lodash';
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4. Once you have imported the negate function, you can now use it in your code. The negate function takes a predicate function as an argument, and returns a new function that will return the opposite boolean value of the original predicate function.

Here's an example usage of the negate function in TypeScript:

index.ts
const isEven = (n: number) => n % 2 === 0;

const isOdd = negate(isEven);

console.log(isOdd(3)); // Output: true
console.log(isOdd(4)); // Output: false
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In this example, we first define a isEven predicate function that returns true if the input number is even. Then, we use the negate function to create a new isOdd function that returns true if the input number is odd (i.e., the opposite of isEven). Finally, we call both functions with different input numbers and observe the results.

That's it! This is how you can use the negate function from the lodash library in TypeScript.