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

To use the keyBy function from the Lodash library in TypeScript, first you need to install the Lodash library. You can install the Lodash library by running the following command in your terminal:

npm install lodash
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After installing the Lodash library, import the keyBy function from the Lodash library in your TypeScript file:

index.ts
import { keyBy } from 'lodash';
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The keyBy function creates an object composed of keys generated from the results of running each element of the array through a given iteratee function.

Here's an example usage of keyBy in TypeScript:

index.ts
interface User {
  id: number;
  name: string;
  age: number;
}

const users: User[] = [
  { id: 1, name: 'John Smith', age: 30 },
  { id: 2, name: 'Jane Doe', age: 25 },
  { id: 3, name: 'Bob Johnson', age: 40 }
];

const usersById = keyBy(users, 'id');

console.log(usersById);
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In this example, we have an array of User objects. We then use the keyBy function to create an object with the id property of each User object as the key and the User object itself as the value. The resulting object looks like this:

{
  "1": {
    "id": 1,
    "name": "John Smith",
    "age": 30
  },
  "2": {
    "id": 2,
    "name": "Jane Doe",
    "age": 25
  },
  "3": {
    "id": 3,
    "name": "Bob Johnson",
    "age": 40
  }
}
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