how to use the isundefined function from lodash in javascript

To use the isUndefined function from lodash in JavaScript, you first need to install the lodash library. You can either install it using npm or include it in your HTML file using a CDN. Once you have installed the library, you can use the isUndefined function as shown below:

index.tsx
// Import the isUndefined function from Lodash
const { isUndefined } = require('lodash');

// Use the isUndefined function
let foo;
console.log(isUndefined(foo)); // Output: true

foo = 'bar';
console.log(isUndefined(foo)); // Output: false
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In the above example, we first import the isUndefined function from lodash using require(). Then we declare a variable foo without initializing it. When we pass this variable to the isUndefined function, it returns true because the variable is undefined. Later, we initialize foo with the value 'bar' and pass it to the isUndefined function which returns false.