TYPESCRIPT Free Section Starter Challenge 30 min

5. Built-in Utility Types: Partial, Pick & Omit

Overview: Leverage TypeScript utility types Partial<T>, Pick<T, K>, and Omit<T, K> for DRY and flexible type definitions.

Concept & Syntax Guide

TypeScript provides powerful built-in type transformations. `Partial<T>` makes all properties optional (ideal for update payloads), while `Pick<T, K>` creates a subset type containing only specified keys.

Hands-On Practice Exercise

Define a Partial Customer Update Type

Given an interface `Customer`, create an update payload type using `Partial<Customer>` and demonstrate valid instantiation.

Target Output: Customer update verified

Need a hint? Click here to reveal

Hint: Check syntax carefully and make sure your code contains: Customer update verified

TYPESCRIPT Code Editor

1
2
3
4
5
6
7
8
9
10

interface Customer {
  id: number;
  name: string;
  email: string;
  isLifetimeVip: boolean;
}

// Use Partial for patch updates
type CustomerUpdate = Partial<Customer>;

const patch: CustomerUpdate = {
  isLifetimeVip: true
};

console.log('Customer update verified: ' + JSON.stringify(patch));