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Tip of the Day — Typescript dynamic types

In Typescript, we can make our types dynamic with union types, intersection types, and index signatures.

union types

A union type allows us to define a variable with multiple types.

let myVar: number | string;

intersection types

An intersection type combines multiple types into one.

interface IEmployee {
id: string;
age: number;
name: string;
interface IContractEmployee {
termDuration: string;
type A = IEmployee & IContractEmployee;let x: A;x.age = 5; = 'CID5241';
x.termDuration = 'one week';

index signatures

In javascripy we can access to a member of an object by key. This is where we use index signature types.

type RestrictedStyleAttribute = "color" | "background-color" | "font-weight";type IRestrictedStyle = {
[T in RestrictedStyleAttribute]: string;




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