how to get all combinations of a set in swift

main.swift
func getCombinations<T>(from elements: [T], choose: Int) -> [[T]] {
    guard choose > 0 else { return [] } // edge case, no elements to choose, return empty array
    guard choose != 1 else { return elements.map { [$0] } } // base case, choose 1 element, return each element as array
    var combinations = [[T]]()
    for (index, element) in elements.enumerated() {
        var reducedElements = elements
        reducedElements.removeFirst(index+1) // get all combinations from remaining elements
        let subCombinations = getCombinations(from: reducedElements, choose: choose - 1)
        for subCombination in subCombinations {
            combinations.append([element] + subCombination) // add the current element with subcombination
        }
    }
    return combinations
}
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main.swift
let elements = [1, 2, 3, 4]
let combinations = getCombinations(from: elements, choose: 3)
print(combinations)
// Output: [[1, 2, 3], [1, 2, 4], [1, 3, 4], [2, 3, 4]]
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