Скачать или смотреть Josh Goldberg - TypeScript for JavaScripties

We'll cover the major points of what TypeScript is and why we want it:
1. From JavaScript to TypeScript: Why JavaScript is the way it is with respect to types (or lack thereof), and where TypeScript does or does not fit in. This includes "duck typing" vs. "structural typing".
2. The Type System: Foundations of how TypeScript's type system fits into JavaScript code and understands your values. This includes syntax errors vs type errors and TypeScript-specific type annotations syntax
3. Unions and Literals: How TypeScript understands values that can be one or multiple possible primitives, along with strict null checking (the "billion dollar mistake") and the powerful concept of "type narrowing"
4. Type narrowing: TypeScript understanding conditionals to "narrow" values' types in blocks of code
5. Objects: How TypeScript's "structural typing" allows it to understand objects by their shape and intent, not just by their declaration forms
For attendees who aren't yet familiar with TypeScript, this will get them excited about the system & understanding how to get started with it. For attendees who already know TypeScript, this will help contextualize its core foundations & show off some core features many TypeScript devs don't yet know.