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iOS Intermediate Swift 2 Extensions and Protocols Protocol Conformance Through Extensions

Sheng Wei
Sheng Wei
4,382 Points

[Help!] How to write conformance protocol through extensions?

Task: Extend User to conform to PrettyPrintable by adding a computed property that returns a formatted description of a User instance. The specifics of the formatted description don't matter

(Also, the engine for this challenge doesn't seem to accept any of my inputs. The moderators might want to check this out!)

protocol PrettyPrintable {
    var prettyDescription: String { get }

struct User {
    let name: String
    let ID: Int

// Enter your code below

extension User: PrettyPrintable {
       var user: String {
           return "User is Great!"

1 Answer

Wei, here's a version that works, to help you get going:

extension User: PrettyPrintable {
    var prettyDescription: String {
        return "UserName: \(name), UserID: \(ID)"

let u1 = User(name: "Sheng Wei", ID: 14)
u1.prettyDescription  //displays "UserName: Sheng Wei, UserID: 14"

You need a computed property named prettyDescription that returns a String, as yours does. But then you need to return a String that formats the name in the way requested.