se-0320.swift

import Foundation

struct Wrapper: Codable, Hashable, RawRepresentable, ExpressibleByStringLiteral, CodingKeyRepresentable {
    typealias StringLiteralType = String
    
    var rawValue: String
    
    init(rawValue: String) {
        self.rawValue = rawValue
    }
    
    init(stringLiteral value: String) {
        self.rawValue = value
    }
}

let test: [Wrapper: Int] = [
    "a": 1,
    "b": 2
]

let encoded = try JSONEncoder().encode(test)
print("Encoded", String(data: encoded, encoding: .utf8)!)

// outputs: Encoded {"b":2,"a":1}
// without `CodingKeyRepresentable` conformance it prints: Encoded ["b",2,"a",1]