The array value should be sort like (alphabetic, numbers and special characters)

Question

I tried to sort like the array as follows:

let students: Set = [\"23412334\",\"&234@fwv\",\"Kofi\", \"Abena\", \"Peter\", \"Kweku\", \"Akosua\"]
let sortedSt         


        

Answer 1

The "correct" way to do it is to define your own sort comparator and use sorted(by:) which sorts using your comparator. In the example below, I define a "priority" based on the category of the first character in the string, and then a two level sort based first on priority and then on the normal string ordering

extension String
{
    enum Priority
    {
        case normal
        case low
        case lowest
        static let lowPriority: Set = Set(["0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "0"])
        static let lowestPriority: Set = Set(["&"])

        static func < (a: Priority, b: Priority) -> Bool
        {
            switch (a, b)
            {
            case (.normal, .low), (.normal, .lowest), (.low, .lowest):
                return true
            default:
                return false
            }
        }
    }

    var priority: Priority
    {
        let first = self.characters.first! // fatal error for empty strings
        if Priority.lowestPriority.contains(first)
        {
            return .lowest
        }
        else if Priority.lowPriority.contains(first)
        {
            return .low
        }
        return .normal
    }
}

let students: Set = ["23412334","&234@fwv","Kofi", "Abena", "Peter", "Kweku", "Akosua"]

let sortedStudents = students.sorted {
    (a, b) -> Bool in
    if a.priority < b.priority
    {
        return true
    }
    else if b.priority < a.priority
    {
        return false
    }
    return a < b
}
print(sortedStudents)

There may be bugs still, but it works for your test case.