2_How to Sort by Multiple Properties in Swift?

StudentSortedByAddressAndAge.swift

let sortedByAddressAndAge = Student.students.sorted {
    if $0.address == $1.address {
        return $0.age < $1.age
    }
    
    return $0.address < $1.address
}

/* Output:

[
    Student(rollNumber: 6, name: "Alma Johansen", address: "Assens", age: 38),
    Student(rollNumber: 7, name: "Björn Jesse", address: "Oberhof", age: 54),
    Student(rollNumber: 8, name: "Judith Fletcher", address: "Perth", age: 66),
    Student(rollNumber: 4, name: "Paula Palmer", address: "Perth", age: 67),
    Student(rollNumber: 5, name: "Arthur Fisher", address: "Pomona", age: 29),
    Student(rollNumber: 2, name: "Armin Berger", address: "Rüthi (Sg)", age: 63),
    Student(rollNumber: 3, name: "Levi Black", address: "Southampton", age: 45),
    Student(rollNumber: 1, name: "Horst-Peter Krafft", address: "Viersen", age: 54)
] 
*/