Ambient Declarations

• Introduction
• Declaration Files
• Best Practices

Introduction

Ambient declarations allow you to safely use existing popular JavaScript libraries and incrementally migrate your JavaScript/CoffeeScript/Other-Compile-To-Js-Language project to TypeScript.

Declaration Files

Syntax is simple:

declare var foo: any

Declarations can be put in a .ts or .d.ts file, ie: global.d.ts or vendor.d.ts

Best Practices

• Use .d.ts
• Use [TypeScript Interfaces](TypeScript Interfaces) where possible