Given 2 sets (unions), return its Cartesian product in a set of tuples, e.g.
CartesianProduct<1 | 2, 'a' | 'b'>
// [1, 'a'] | [2, 'a'] | [1, 'b'] | [2, 'b']
Solution:
/* _____________ Your Code Here _____________ */
type CartesianProduct<T, U> = T extends infer T1
? U extends infer U1
? [T1, U1] | CartesianProduct<Exclude<T, T1>, Exclude<U, U1>>
: never
: never
/* _____________ Test Cases _____________ */
import type { Equal, Expect } from '@type-challenges/utils'
import { ExpectFalse, NotEqual } from '@type-challenges/utils'
type cases = [
Expect<Equal<CartesianProduct<1 | 2, 'a' | 'b'>, [2, 'a'] | [1, 'a'] | [2, 'b'] | [1, 'b']>>,
Expect<Equal<CartesianProduct<1 | 2 | 3, 'a' | 'b' | 'c' >, [2, 'a'] | [1, 'a'] | [3, 'a'] | [2, 'b'] | [1, 'b'] | [3, 'b'] | [2, 'c'] | [1, 'c'] | [3, 'c']>>,
Expect<Equal<CartesianProduct<1 | 2, 'a' | never>, [2, 'a'] | [1, 'a'] >>,
Expect<Equal<CartesianProduct<'a', Function | string>, ['a', Function] | ['a', string]>>,
]