Mastering TypeScript 3 - Third Edition

Declaration syntax reference

When creating declaration files and using the module keyword, there are a number of rules that can be used to mix and match definitions. As a TypeScript programmer, you will generally only write module definitions every now and then, and on occasion, you will need to add a new definition to an existing declaration file.

This section, therefore, is designed to be a quick reference guide to this declaration file syntax, or a cheat sheet. Each section contains a description of the module definition rule, a JavaScript syntax snippet, and then the equivalent TypeScript declaration file syntax.

To use this reference section, simply match the JavaScript that you are trying to emulate from the JavaScript syntax section, ...