TypeScript Weekly

Issue #174 — July 19, 2021

Announcing TypeScript 4.4 Beta

The beta of TypeScript 4.4 is out and brings control flow analysis of aliased conditions, a new flag for exact optional property types, symbol and template string pattern index signatures, and more.

Daniel Rosenwasser

TypeScript: Array.includes and Narrowed Types

The Array.prototype.includes function allows searching for a value within an array. However, in certain cases, the typings can bite a little. Stefan explains the reason why and suggest two possible solutions.

Stefan Baumgartner

TypeScript and Native ESM in Node.js

An overview of everything you need to know in order to use and produce native ECMAScript modules in Node.js.

Dr. Axel Rauschmayer

TypeScript, Abstract Classes, and Constructors

TypeScript has the ability to define classes as abstract. This means they cannot be instantiated directly; only non-abstract subclasses can be. John explains what this means for constructor usage.

John Reilly

sinclairzx81 / typebox

TypeBox allows you to create a single unified type that can be both statically checked by the TypeScript compiler and asserted at runtime using standard JSON schema validation.