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The #1 TypeScript book for JavaScript developers out today

By Josh Goldberg
Book cover: Learning TypeScript: Enhance Your Web Development Skills Using Type-Safe JavaScript

Learning TypeScript will take you from knowing nothing about "types" or a "type system" to full mastery of the fundamentals of TypeScript.

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Top tips and tricks for why TypeScript behaves the way it does, and how you can work effectively with it.

Why TypeScript Doesn't Include a `throws` Keyword
Why a `throws` keyword has not been added to TypeScript, despite some other languages having an equivalent.
Tags: checked exceptions, errors, throw, throw types, try catch
Narrowing Function Parameters With Rests And Tuples
Using rest parameters and tuples to apply union type narrowing to a function's parameters
Tags: arguments, functions, parameters, rest, spread, tuples, unions
Why TypeScript Doesn't Follow Strict Semantic Versioning
Why it's not practically feasible -or desirable- for a programming language like TypeScript to use strict semantic versioning for its releases.
Tags: ECMAScript, compiler options target, TSConfig
Why Increase Your TSConfig `target`
Why you should increase the value in your TSConfig to as recent an ECMAScript version as you can.
Tags: ECMAScript, compiler options target, TSConfig
The `satisfies` Operator
How TypeScript's new `satisfies` operator brings the best of type annotations and default type inference.
Tags: assertions casts declarations satisfies
Objects, Functions, and Type Narrowing
Diving into why TypeScript doesn't narrow object types before they're modified.
Tags: objects, narrowing, variables
Extreme Explorations of TypeScript's Type System
Some of the most creative, wacky explorations of what you can do in TypeScript's type system!
Tags: metaprogramming, type system
Void-Returning Function Assignability
Why functions that return a value are assignable to void-returning function types in TypeScript.
Tags: assignabiity, functions, void
References in the Learning TypeScript Book
An exhaustive list of all the easter eggs and general references in the Learning TypeScript book.
Tags: easter eggs, meta
See all 9 articles

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Learning TypeScript

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Go from knowing nothing about β€œtypes” or "type systems" to full mastery of TypeScript fundamentals – whether you're a beginner or advanced JavaScript programmer.

About the author

Josh Goldberg
Hi, I'm Josh! I'm a full time independent open source developer with a passion for static analysis, and the web. I'm a full time open source maintainer and work on projects in the TypeScript ecosystem such as typescript-eslint and TypeStat. I'm passionate about bringing accessible education to the masses in a sustainable way.Visit my Site β†—