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

To use the extend function from the Lodash library in TypeScript, the first step is to install the Lodash library using npm:

npm install lodash
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After that, you can import the extend function from the lodash module:

index.ts
import { extend } from 'lodash';
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The extend function takes in two or more objects as arguments and extends the first object with the properties and values of the other objects:

index.ts
interface MyInterface {
  foo: string;
  bar: number;
}

const obj1: MyInterface = {foo: 'hello', bar: 42};
const obj2 = {baz: true};

extend(obj1, obj2);

console.log(obj1); // {foo: 'hello', bar: 42, baz: true}
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Here, obj1 is extended with the properties and values of obj2. Note that the obj1 parameter is modified in place and returned. If you want to create a new object instead, you can pass an empty object as the first parameter:

index.ts
const obj1: MyInterface = {foo: 'hello', bar: 42};
const obj2 = {baz: true};

const newObj = extend({}, obj1, obj2);

console.log(newObj); // {foo: 'hello', bar: 42, baz: true}
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In this case, newObj is a new object that contains the properties and values of obj1 and obj2, without modifying either object.

Overall, using extend from the Lodash library in TypeScript is a convenient way to extend objects with additional properties or overwrite existing properties while preserving type safety.