Create cartesian product

JavaScript version
const cartesian = (...sets) => sets.reduce((acc, set) => acc.flatMap((x) => set.map((y) => [...x, y])), [[]]);
Example
cartesian([1, 2], [3, 4]); // [ [1, 3], [1, 4], [2, 3], [2, 4] ]
/*
3 4
---------------
1 | [1, 3] [1, 4]
|
2 | [2, 3] [2, 4]
*/