00010-medium-tuple-to-union.ts

/*
  10 - Tuple to Union
  -------
  by Anthony Fu (@antfu) #medium #infer #tuple #union
  
  ### Question
  
  Implement a generic `TupleToUnion<T>` which covers the values of a tuple to its values union.
  
  For example
  
  ```ts
  type Arr = ['1', '2', '3']
  
  type Test = TupleToUnion<Arr> // expected to be '1' | '2' | '3'
  ```
  
  > View on GitHub: https://tsch.js.org/10
*/

/* _____________ Your Code Here _____________ */

type TupleToUnion<T extends any[]> = T[number];

/* _____________ Test Cases _____________ */
import type { Equal, Expect } from "@type-challenges/utils";

type cases = [
  Expect<Equal<TupleToUnion<[123, "456", true]>, 123 | "456" | true>>,
  Expect<Equal<TupleToUnion<[123]>, 123>>
];

/* _____________ Further Steps _____________ */
/*
  > Share your solutions: https://tsch.js.org/10/answer
  > View solutions: https://tsch.js.org/10/solutions
  > More Challenges: https://tsch.js.org
*/