CustomStringConvertible.swift

import Foundation

extension CustomStringConvertible {
    var description: String {
        var description: String = "\(type(of: self))("
        
        let selfMirror = Mirror(reflecting: self)
        
        for child in selfMirror.children {
            if let propertyName = child.label {
                description += "\(propertyName): \(child.value), "
            }
        }
        
        description += "<\(Unmanaged.passUnretained(self as AnyObject).toOpaque())>)"
        
        return description
    }
}

class Person: CustomStringConvertible {
    let name: String
    let age: Int
    
    init (name: String, age: Int) {
        self.name = name
        self.age = age
    }
}

let alex = Person(name: "Alex", age: 20)
print(alex) // Person(name: Alex, age: 20, <0x000060c000058d20>)