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Includes<T, U>

MediumP2Coding

Implement Includes<T, U>: true if the tuple T contains an element whose type is exactly U, otherwise false.

Exact means type equality, not assignability: Includes<[boolean, 2], false> is false, and Includes<[1], 1 | 2> is false.

Tests your type must pass

type cases = [
  Expect<Equal<Includes<['Kars', 'Esidisi', 'Wamuu', 'Santana'], 'Kars'>, true>>,
  Expect<Equal<Includes<['Kars', 'Esidisi', 'Wamuu', 'Santana'], 'Dio'>, false>>,
  Expect<Equal<Includes<[1, 2, 3, 5, 6, 7], 7>, true>>,
  Expect<Equal<Includes<[1, 2, 3, 5, 6, 7], 4>, false>>,
  Expect<Equal<Includes<[1, 2, 3], 2 | 3>, false>>,
  Expect<Equal<Includes<[boolean, 2, 3, 5, 6, 7], false>, false>>,
  Expect<Equal<Includes<[true, 2, 3, 5, 6, 7], boolean>, false>>,
  Expect<Equal<Includes<[false, 2, 3, 5, 6, 7], false>, true>>,
  Expect<Equal<Includes<[{}], { a: 'A' }>, false>>,
  Expect<Equal<Includes<[readonly [1]], [1]>, false>>,
  Expect<Equal<Includes<[null], undefined>, false>>,
  Expect<Equal<Includes<[], 1>, false>>,
]

Hints

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