Lessons
An introduction to writing TypeScript
TypeScript · Introductory. Ten lessons. Open-book quizzes. Lesson 1 free.
10 lessons · The Host · Lesson 1 free
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Lesson 1 · On the house
Types beside JavaScript
TypeScript is JS with a type checker.
Lesson 2
number, string, boolean, inference
Primitives and inference.
Lesson 3
Arrays and tuples
T[] vs [T, U].
Lesson 4
Interfaces and type aliases
Shapes of objects.
Lesson 5
Unions and narrowing
string | null and control flow.
Lesson 6
Functions
Params, returns, optional.
Lesson 7
Literal types
Limited sets of values.
Lesson 8
Classes sketch
Fields and constructors.
Lesson 9
Modules and import type
ES modules with types.
Lesson 10
A small typed program
Compose types and narrowing.
Sample certificate
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Certificate
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