print array in struct in alphabetical order and in

Question

I would like my struct to print its entries in alphabetical order first, then arrange the data in descending order. So the final result would be: "lukes 9", "lukes 4", "smiths 4"

struct MyData {
    var company = String()
    var score: Int
}

let data = [
    MyData(company: "smiths", score: 4 ),
    MyData(company: "lukes", score: 4),
    MyData(company: "lukes", score: 9)
]

Answer 1

There's 2 ways you can do this. Both would require you to pass your array to sort (Swift 2), now sorted (Swift 3).

1. A very easy implementation:

   struct MyData {
       var company = String()
       var score: Int
   }
   
   let data = [
       MyData(company: "smiths", score: 4),
       MyData(company: "lukes", score: 4),
       MyData(company: "lukes", score: 9)
   ]
   
   let sortedArray = data.sorted(by: { ($0.company, $1.score) < ($1.company, $0.score) })
   

2. You could also make MyData conform to Comparable. This keeps the comparison logic within the MyData type, and you can just run the sorted() function to return a new array:

   struct MyData {
       var company = String()
       var score: Int
   }
   
   extension MyData: Equatable {
       static func ==(lhs: MyData, rhs: MyData) -> Bool {
           return (lhs.company, lhs.score) == (rhs.company, rhs.score)
       }
   }
   
   extension MyData: Comparable {
        static func <(lhs: MyData, rhs: MyData) -> Bool {
           return (rhs.company, lhs.score) > (lhs.company, rhs.score)
       }
   }  
   
   let data = [
       MyData(company: "smiths", score: 4),
       MyData(company: "lukes", score: 4),
       MyData(company: "lukes", score: 9)
   ]
   
   let sortedArray = data.sorted()
   

These 2 implementations both output your desired result: "lukes 9", "lukes 4", "smiths 4"