TypeScript

Part 1: The basics

What TypeScript adds, your first annotations, making the compiler catch a real bug, and values that might be missing.

1. 1TypeScript from zero50 min · 4 steps

Part 2: Functions and reuse

Typing functions you pass around, generics that keep the type, and the built-in helper types.

1. 2Functions, generics and the built-in helpers50 min · 3 steps

Part 3: The real world

Checking data from outside, modelling state so impossible ones cannot exist, and the escape hatches.

1. 3Data from outside, and modelling state50 min · 3 steps

Part 4: Reading the compiler

What the compiler sees, narrowing, and the parts that still run.

1. 4TypeScript: types that catch bugs40 min · 3 steps

Part 5: Project

Type a whole module: a model nothing can contradict, one checked boundary, states that cannot be impossible, and failures returned as values.

1. 5Project: type the quote module end to end70 min · 4 steps