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

To use the update function from the Lodash library in Typescript, you will first need to install the Lodash library and its TypeScript definitions.

Here is an example of how you can use the update function in TypeScript:

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

interface User {
  name: string;
  age: number;
  address: {
    street: string;
    city: string;
  };
}

const user: User = {
  name: 'John',
  age: 30,
  address: {
    street: '123 Main St',
    city: 'Anytown USA'
  }
};

// Update user's age property
const updatedUser = _.update(user, 'age', age => age + 1);

// Update user's city property
const updatedUser2 = _.update(user, 'address.city', city => 'New York');

console.log(updatedUser);
console.log(updatedUser2);
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In the example above, we import the entire Lodash library using the import * as _ from 'lodash'; statement.

We then define an interface User that represents an object with a name, age, and address property.

We declare a user object that conforms to the User interface.

We use the _.update function to update the age property of the user object. The _.update function takes three arguments: the object to update, a string representing the path to the property to update, and a function that returns the new value of the property.

We also use the _.update function to update the city property of the address object within the user object. In this case, the path argument is a nested path using dot notation.

Finally, we log out the updated user object and the updated address object with the new city property.