Sample case of Retain Cycle in Swift

swift_memory_management_1.swift

import Foundation

// MARK: - Swift Memory Management

class Tutorial {
  let title: String
  unowned let author: Author
  weak var editor: Editor?
  
  init(title: String, author: Author) {
    self.title = title
    self.author = author
  }
  
  deinit {
    print("Sampai jumpa lagi tutorial \(title)!")
  }
}

class Editor {
  let name: String
  var tutorials: [Tutorial] = []
  
  init(name: String) {
    self.name = name
  }
  
  deinit {
    print("Sampai jumpa lagi editor \(name)!")
  }
}

class Author {
  let name: String
  var tutorials: [Tutorial] = []
  
  init(name: String) {
    self.name = name
  }
  
  deinit {
    print("Sampai jumpa lagi author \(name)!")
  }
}


do {
  let author = Author(name: "Martin")
  let tutorial = Tutorial(
    title: "Swift Memory Management",
    author: author
  )
  let editor = Editor(name: "Joko")
  author.tutorials.append(tutorial)
  tutorial.editor = editor
  editor.tutorials.append(tutorial)
}