TypeScript

4.4 beta

https://devblogs.microsoft.com/typescript/announcing-typescript-4-4-beta

Control flow analysis of aliased conditional expressions and discriminants

https://github.com/microsoft/TypeScript/pull/44730

4.3

https://devblogs.microsoft.com/typescript/announcing-typescript-4-3

Design Goals

https://github.com/Microsoft/TypeScript/wiki/TypeScript-Design-Goals

Deep Dive

https://www.typescriptlang.org/docs/handbook/declaration-files/deep-dive.html

Deep Dive (Basarat)

https://basarat.gitbook.io/typescript