​TS Handbook and this article are great intros.

Notes

• TypeScript can figure the return type out by looking at the return statements, so we can also optionally leave this off in many cases

• You really shouldn’t use arrow function as class members. Arrow functions are duplicated in memory for each class instance, while proper method members are written once in your class’s prototype and shared between all instances.

• ​Unlike classes, an interface is a virtual structure that only exists within the context of TypeScript. The TypeScript compiler uses interfaces solely for type-checking purposes.​

• any means “ignore the type”, unknown means “we don’t know the type”, which aren’t the same thing, and for better code you’d rather not know the type than ignore it.

• You can’t use unknown as a simple replacement for any, that wouldn’t make sense. unkwnown carries the implication that you should not use this variable other than passing it around. Or testing its type to get rid of the “unknown” state.

• Tuples are very useful for simulating multiple returns like React hooks, and other combined values that don't need string object keys

Links

• ​TypeScript Language Specification​

• ​TypeScript code​

• ​React & Redux in TypeScript - Static Typing Guide​

• ​Opening Remarks by Anders Hejlsberg (2018)​

• ​Ultimate React Component Patterns with Typescript 2.8​

• ​Very opinionated front end boilerplate​

• ​Babel 7 + TypeScript​

• ​Classes vs interfaces in TS​

• ​StREST - Set up tests for REST in seconds with YAML.

• ​Fork TS Checker Webpack Plugin - Webpack plugin that runs typescript type checker on a separate process.

• ​Tsickle - TypeScript to Closure Translator.

• ​Set of TSLint rules used on some Microsoft projects​

• ​TypeScript ESLint - Monorepo for all the tooling which enables ESLint to support TypeScript.

• ​TypeScript With Babel: A Beautiful Marriage (2018)​

• ​ts-node-dev - Restarts target node process when any of required files changes (as standard node-dev) but shares Typescript compilation process between restarts.

• ​When to use never and unknown in Typescript (2019)​

• ​bibliography on Gradual Typing​

• ​dtslint - Tests a TypeScript declaration file for style and correctness.

• ​Clean Code concepts adapted for TypeScript​

• ​SonarTS - Static code analyzer for TypeScript.

• ​TypeScript TSLint Language Service Plugin​

• ​TypeScript Guidelines - Guideline to focus on how to write effective TypeScript with minimal effort.

• ​Practical Advanced TypeScript​

• ​typescript-json-schema - Generate json-schemas from your Typescript sources.

• ​tslint-config-security - TSLint security rules.

• ​TypeScript Definition Style Guide​

• ​Conditional Type Checks - Types for testing TypeScript types.

• ​quicktype - Generate types and converters from JSON, Schema, and GraphQL.

• ​Collection of essential TypeScript types​

• ​Be Super with TypeScript and Jared Palmer episode (2019)​

• ​typesync - Install missing TypeScript typings for dependencies in your package.json.

• ​TSdx - Zero-config CLI for TypeScript package development.

• ​Programming TypeScript book Boris Cherny (2019)​

• ​OneFraction - React/ApolloGraphQL/Node/Mongo demo written in Typescript.

• ​TypeScript 3.0: The unknown Type (2019)​

• ​Lobsters: What have you learned from adopting Typescript into an existing JS codebase? (2019)​

• ​React+TypeScript Cheatsheets​

• ​Using Typescript to make invalid states irrepresentable​

• ​High-level notes about TypeScript​

• ​TypeCov - Track missing type coverage to ensure type safety.

• ​type-coverage - CLI tool to check type coverage for typescript code.

• ​TSDoc Standard - Standard but also use TypeScript on JS files with jsdoc.

• ​Typescript Generics Tutorial (2019)​

• ​ts-morph - TypeScript Compiler API wrapper. Provides an easier way to navigate and manipulate TypeScript and JavaScript code.

• ​tsconfig-paths - Load node modules according to tsconfig paths, in run-time or via API.

• ​ts-json-schema-generator - Generate JSON schema from your Typescript sources.

• ​TSQuery - Allows you to query a TypeScript AST for patterns of syntax using a CSS style selector system.

• ​Interpreting TypeScript (Article)

• ​TSDX - Zero-config CLI for TypeScript package development.

• ​TypeScript Weekly - Best TypeScript links every week, right in your inbox. (Archive)

• ​Rush Stack - Reusable tooling for large scale TypeScript monorepos. (Web)

• ​Debugging the TypeScript Codebase (2019)​

• ​The ultimate explanation of TypeScript generics: functions (2019)​

• ​TypeScript 3.7 Utility Types Cheat Sheet​

• ​TypeScript Generics for People Who Gave Up on Understanding Generics (2019)​

• ​Blogged Answers: Learning and Using TypeScript as an App Dev and a Library Maintainer (2019)​

• ​Runtypes - Runtime validation for static types.

• ​Stringly and Strongly typed TypeScript (2019)​

• ​Type Families in Typescript (2019)​

• ​TSConf 2019 Keynote - Anders Hejlsberg​

• ​Effective Typescript book (Code)

• ​Effective Typescript notes​

• ​TypeScript for Beginner Programmers​

• ​TSConf Videos​

• ​gts - TypeScript style guide, formatter, and linter by Google.

• ​Typing correctly matters (2019)​

• ​Is TypeScript worth it? (2020) (HN)

• ​React with TypeScript: Best Practices (2020)​

• ​dts-gen - TypeScript Definition File Generator.

• ​Nimbus - Centralized CLI for JavaScript and TypeScript developer tools.

• ​Naive approach to functional programming using TypeScript​

• ​Meta-Typing - Various functions and algorithms implemented purely with TypeScript's type system.

• ​Designing the perfect Typescript schema validation library​

• ​How to setup TypeScript and use in a normal JavaScript project for learning purposes​

• ​Dependent Types in Typescript​

• ​Type Puzzles - Learn TypeScript with Type Puzzles. (Code)

• ​Introduction to Functional Programming using TypeScript and fp-ts​

• ​TypeScript website code - Website and web infrastructure for learning TypeScript.

• ​Functional TypeScript - TypeScript standard for rock solid serverless functions.

• ​TSJS-lib-generator - TypeScript and JavaScript lib generator.

• ​TypeScript exercises - Collection of challenging TypeScript exercises.

• ​sane-fmt - Opinionated code formatter for TypeScript and JavaScript.

• ​Benchmark Comparison of Packages with Runtime Validation and Typescript Support​

• ​TypeScript Language Server​

• ​TypeScript Playground Collaborate​

• ​Centralized Recommendations for TSConfig bases​

• ​Typescript Data Structures and Algorithms - Collection of classic data structures and algorithms implemented in Typescript with video lectures.

• ​TypeDoc - Documentation generator for TypeScript projects. (Web)

• ​Advanced TypeScript Types cheat sheet (with examples) (2020)​

• ​TypeScript interactive course​

• ​ts-migrate - Tool to automatically migrate JavaScript projects to TS. (HN)

• ​Exhaustive matching in TypeScript (2020)​

• ​TypeScript for Professionals (2020)​

• ​The Single-Valued Type Pattern for TypeScript (2020)​

• ​TypeScript in 50 Lessons book​

• ​TypeScript notes/links​

• ​Data Constructors, Part 1: Understanding by Implementing (2020)​

• ​TypeScript: accessing members of a union type (2020)​

• ​PlayCode - JavaScript/TypeScript Playground.

• ​Utilities for TypeScript and Bazel​

• ​End-to-End TypeScript: Database, Backend, API, and Frontend (2020)​

• ​TypeScript Transformer Handbook​

• ​How does the TypeScript team try to avoid negative effects on the JS ecosystem? (2020)​

• ​TypeChallenges - Collection of TypeScript type challenges with online judge.

• ​Insights from Adopting TypeScript at Scale (2020) (Tweet) (HN)

• ​TypeScript splits the atom A first look at TS 4.1's new template literal types (2020)​

• ​TypeScript Coverage Report - Node command line tool for generating TypeScript coverage reports.

• ​ts-unused-exports - Finds unused exported symbols in your Typescript project.

• ​Learn TypeScript: A Pocketguide Tutorial (2020)​

• ​TypeScript 4.1 (2020) (HN)

• ​ts-monorepo - Template for setting up a TypeScript monorepo.

• ​Tips for Performant TypeScript (HN)

• ​A case study on strict null checks (2020) (HN)

• ​TypeScript LSIF indexer​

• ​ttypescript (Transformer TypeScript) - TypeScript tool to use custom transformers in the tsconfig.json.

• ​json2ts - Generate TypeScript interfaces from JSON.

• ​Go JSON to TypeScript model converter​

Images

TypeScript’s type hierarchy