arrays - 是否可以从具有 nil 值的数组中删除重复值

Question

数组可以是任何类型，例如

let myArray1 = [ 1, 2, 3, 1, 2, 1, 3, nil, 1, nil]

let myArray2 = [ 1, 2.0, 1, 3, 1.0, nil]

从数组中删除重复值后，新数组应该是:

输出-

 [ 1, 2, 3, nil ]

Answer 1

@Daniel 作为通用函数的解决方案:

func uniqueElements<T: Equatable>(of array: [T?]) -> [T?] {
    return array.reduce([T?]()) { (result, item) -> [T?] in
        if result.contains(where: {$0 == item}) {
            return result
        }
        return result + [item]
    }
}

let array = [1,2,3,1,2,1,3,nil,1,nil]

let r = uniqueElements(of: array) // [1,2,3,nil]