1. Introduction to TypeScript & Setup
TypeScript is a statically typed superset of JavaScript developed by Microsoft. Because it builds on top of JavaScript, every valid JavaScript file is also a valid TypeScript file,...
Read full chapter →The essential Typescript Essentials cheat sheet: 8 concise chapters you can read in minutes, distilled from the full deck. When you're ready, drill the flashcards or test yourself under exam conditions.
TypeScript is a statically typed superset of JavaScript developed by Microsoft. Because it builds on top of JavaScript, every valid JavaScript file is also a valid TypeScript file,...
Read full chapter →TypeScript's type system starts with a small set of primitive types: number, string, boolean, null, undefined, symbol, and bigint. These primitives serve as the building blocks for...
Read full chapter →TypeScript supports multiple ways to express collections of values. Arrays can be written using either bracket syntax, such as let numbers: number[] = [1, 2, 3];, or the generic Ar...
Read full chapter →Interfaces describe the shape of objects by declaring the names and types of their members. A simple interface Person { name: string; age: number; } tells the compiler that any val...
Read full chapter →Classes in TypeScript follow standard JavaScript class syntax with the addition of type annotations. A class such as class Animal { name: string; constructor(name: string) { this.n...
Read full chapter →Generics let you write functions, interfaces, and classes that operate on multiple types while preserving full type safety. A generic identity function written as function identity...
Read full chapter →TypeScript supports ES module syntax: import { ModuleName } from './module'; pulls in named exports, import * as Module from './module'; imports a whole namespace, and exports are...
Read full chapter →Strict mode, enabled by setting "strict": true in tsconfig.json, turns on a collection of more rigorous type-checking options, including strictNullChecks and several others. Activa...
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