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JSGroundwork handwritten · web dev

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Chapters

29 chapters

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Beginner8›

B1Setup & compiler B2Basic types B3Functions B4Interfaces & aliases B5Union & intersection B6Enums & literals B7Classes B8DOM & JSON

Intermediate11›

I1Structural typing I2Narrowing I3Runtime validation I4Generics I5Utility types I6Mapped & conditional I7Modules & .d.ts I8tsconfig in depth I9Third-party types I10Typing async code I11Testing typed code

Advanced10›

A1Advanced generics A2Conditional & recursive types A3Type-level programming A4Decorators & metadata A5Structural vs nominal A6Type-check performance A7Monorepo setups A8Migrating from JS A9Compiler API A10End-to-end type safety

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TypeScript levels

1Beginner 2Intermediate 3Advanced

Ready to read

JSJavaScript ⑂Git ◎Interview prep ΣDSA in JS SDSystem Design

More topics15›

</>HTML { }CSS ⚛React NNext.js NeNest.js TSTypeScript NoNode.js 🐳Docker DBSQL & Databases ✓Testing 🔒Web Security ☁Cloud & DevOps ◈GraphQL ◆Redis ☸Kubernetes

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I2

Narrowing

not written yet

This section will cover:

typeof/in/instanceof guards, custom type guards
Discriminated unions

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