Collection of TypeScript type challenges

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(削除) by the power of TypeScript's well-known Turing Completed type system (削除ここまで)

High-quality types can help improve projects' maintainability while avoiding potential bugs.

There are a bunch of awesome type utility libraries that may boost your works on types, like ts-toolbelt, utility-types, SimplyTyped, etc., which you can already use.

This project is aimed at helping you better understand how the type system works, writing your own utilities, or just having fun with the challenges. We are also trying to form a community where you can ask questions and get answers you have faced in the real world - they may become part of the challenges!

Click the following badges to see details of the challenges.

1
13・Hello World

13
4・Pick 7・Readonly 11・Tuple to Object 14・First of Array 18・Length of Tuple 43・Exclude 189・Awaited 268・If 533・Concat 898・Includes 3057・Push 3060・Unshift 3312・Parameters

72
2・Get Return Type 3・Omit 8・Readonly 2 9・Deep Readonly 10・Tuple to Union 12・Chainable Options 15・Last of Array 16・Pop 20・Promise.all 62・Type Lookup 106・Trim Left 108・Trim 110・Capitalize 116・Replace 119・ReplaceAll 191・Append Argument 296・Permutation 298・Length of String 459・Flatten 527・Append to object 529・Absolute 531・String to Union 599・Merge 612・KebabCase 645・Diff 949・AnyOf 1042・IsNever 1097・IsUnion 1130・ReplaceKeys 1367・Remove Index Signature 1978・Percentage Parser 2070・Drop Char 2257・MinusOne 2595・PickByType 2688・StartsWith 2693・EndsWith 2757・PartialByKeys 2759・RequiredByKeys 2793・Mutable 2852・OmitByType 2946・ObjectEntries 3062・Shift 3188・Tuple to Nested Object 3192・Reverse 3196・Flip Arguments 3243・FlattenDepth 3326・BEM style string 3376・InorderTraversal 4179・Flip 4182・Fibonacci Sequence 4260・AllCombinations 4425・Greater Than 4471・Zip 4484・IsTuple 4499・Chunk 4518・Fill 4803・Trim Right 5117・Without 5140・Trunc 5153・IndexOf 5310・Join 5317・LastIndexOf 5360・Unique 5821・MapTypes 7544・Construct Tuple 8640・Number Range 8767・Combination 8987・Subsequence 9896・GetMiddleElement 10969・Integer 16259・ToPrimitive 17973・DeepMutable

40
6・Simple Vue 17・Currying 1 55・Union to Intersection 57・Get Required 59・Get Optional 89・Required Keys 90・Optional Keys 112・Capitalize Words 114・CamelCase 147・C-printf Parser 213・Vue Basic Props 223・IsAny 270・Typed Get 300・String to Number 399・Tuple Filter 472・Tuple to Enum Object 545・printf 553・Deep object to unique 651・Length of String 2 730・Union to Tuple 847・String Join 956・DeepPick 1290・Pinia 1383・Camelize 2059・Drop String 2822・Split 2828・ClassPublicKeys 2857・IsRequiredKey 2949・ObjectFromEntries 4037・IsPalindrome 5181・Mutable Keys 5423・Intersection 6141・Binary to Decimal 7258・Object Key Paths 8804・Two Sum 9155・ValidDate 9160・Assign 9775・Capitalize Nest Object Keys 14188・Run-length encoding 15260・Tree path array

14
5・Get Readonly Keys 151・Query String Parser 216・Slice 274・Integers Comparator 462・Currying 2 476・Sum 517・Multiply 697・Tag 734・Inclusive Range 741・Sort 869・DistributeUnions 925・Assert Array Index 6228・JSON Parser 7561・Subtract

✨ Upcoming challenges

🔥 Start the challenge in TypeScript Playground

⚡️ Start the challenge in VS Code

• The TypeScript Handbook

  • Unions and Intersection Types
  • Literal Types
  • Utility Types
  • Advanced Types

• The New Handbook

• Learn Advanced TypeScript Types
• The Art of Type Programming
• Type Query: jQuery Style Type Manipulation

• Type Level Programming in Typescript

• Type Gymnastics
• Type Challenges Solutions
• TypeType Examples

• Effective TypeScript
• Learning TypeScript

TODO

There are several ways you can contribute to this project

• Share your answers / solutions
• Propose new challenges
• Add more test cases to the existing challenges
• Provide learning resources or ideas of how to solve challenges
• Share the problems you have faced in real-world projects, regardless you having the solution or not - the community would help you as well
• Help with others by discussion in issues
• Contribute the infra of this project TODOs.md

Just open an issue and choose the corresponding template. Thanks!

This project was born from solving real-world types problem with @hardfist and @MeCKodo. And great thanks to @sinoon who contributed a lot while giving early feedback on this project.

• piotrwitek/utility-types
• psmyrdek/typescript-challenges
• andnp/SimplyTyped

Contributors

MIT