Item 66: Understand the Three Versions Involved in Type Declarations

Things to Remember

• There are three versions involved in an @types dependency: the library version, the @types version, and the TypeScript version.
• Recognize the symptoms of different types of version mismatch.
• If you update a library, make sure you update the corresponding @types.
• Understand the pros and cons of bundling types versus publishing them on DefinitelyTyped. Prefer bundling types if your library is written in TypeScript, and DefinitelyTyped if it is not.