get distinct permutations of a set in swift

main.swift
func getPermutations<T>(_ set: Set<T>) -> [[T]] {
    var setArray = Array(set)
    var permutations: [[T]] = []

    func heapPermutation(_ n: Int) {
        if n == 1 {
            permutations.append(setArray)
            return
        }

        for i in 0..<n {
            heapPermutation(n - 1)

            if n % 2 == 1 {
                setArray.swapAt(0, n - 1)
            } else {
                setArray.swapAt(i, n - 1)
            }
        }
    }

    heapPermutation(set.count)
    return permutations
}
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main.swift
let set = Set([1, 2, 3])
let permutations = getPermutations(set)
print(permutations) // Output: [[1, 2, 3], [2, 1, 3], [3, 1, 2], [1, 3, 2], [2, 3, 1], [3, 2, 1]]
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