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Advent of Typescript 2023 Day 21 : TIC TAC TOE

ecyrbe on December 21, 2023

Hello Typescript Wizards, i hope you are having fun with the Advent of Typescript 2023. With Trash we created some awesome challenges for you to so...
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Raijinhasarrived •

day 22

type FlattenArray<T> = T extends [infer U, ...infer Rest]
  ? U extends any[] ? [...FlattenArray<U>, ...FlattenArray<Rest>] : [U, ...FlattenArray<Rest>]
  : [];

type IsValid<T extends any[], U extends any[] = []> = T extends [infer Head, ...infer Tail]
  ? Head extends U[number]
    ? false
    : IsValid<Tail, [Head, ...U]>
  : true;

type Validate<T extends any[]> = T extends [infer First, ...infer Rest] 
  ? IsValid<FlattenArray<First>> extends true
    ? Validate<Rest>
    : false
  : true;
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ecyrbe •

There's a post about it here:
dev.to/ecyrbe/advent-of-typescript...