Simplify<T>

Overview

The Simplify utility type is needed to simplify union TypeScript types by resolving properties into a single structure.

It takes a type T and returns a new type where all the properties of T are retained but any union structures are resolved into a straightforward, plain object type.

This can be particulary useful when dealing with intersection types that might result in verbose or hard-to-read type definitions.

Syntax

type Simplify<T> = { [Key in keyof T]: T[Key] } & {};

• T: The type you want to simplify.

Examples

Example #1

type Crendentials = {
  email: string;
  password: string;
};

type UserInfo = {
  username: string;
  age: number;
  gender: 'M' | 'F';
};

type CreateUserRequest = Simplify<Credentials & UserInfo>;
// If not using `Simplify`, then IDE shows `Credentials & UserInfo`.

// However, the simplified result will be:
// {
//   email: string;
//   password: string;
//   username: string;
//   age: number;
//   gender: 'M' | 'F';
// }