how to get the power set of a set in swift

main.swift
func powerSet<T>(_ set: Set<T>) -> [[T]] {
    let binaryCount = 1 << set.count // calculate the number of binary digits needed
    var powerSet: [[T]] = []
    
    for i in 0..<binaryCount {
        let binary = String(i, radix: 2) // get the binary representation of the current number
        let paddedBinary = binary.padding(toLength: set.count, withPad: "0", startingAt: 0) // pad the binary representation with leading zeros
        let subset = paddedBinary.enumerated().compactMap({ (index, digit) -> T? in
            if digit == "1" {
                return set[set.index(set.startIndex, offsetBy: index)]
            } else {
                return nil
            }
        })
        powerSet.append(subset)
    }
    
    return powerSet
}
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main.swift
let set = Set([1, 2, 3])
let powerSet = powerSet(set)

print(powerSet) // prints "[[], [1], [2], [1, 2], [3], [1, 3], [2, 3], [1, 2, 3]]"
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