DAEUN28/Const

💖 Lovely code for const

Const

💖 Lovely code for const

Summary

From:

class ViewController: UIViewController {
  struct Const {
    static let width: CGFloat = 100
    static let height: CGFloat = 100
    static let backgroundColor: UIColor = .black
  }

  override func viewDidLoad() {
    let subview = UIView(frame: CGRect(x: 0, y: 0, width: Const.width, height: Const.height))
    view.addSubview(subview)
  }
}

To:

class ViewController: UIViewController, ConstConvertable {
  enum Const {
    case width
    case height
    case backgroundColor
    
    var object: Any {
      switch self {
        case .width, .height: return CGFloat(10)
        case .backgroundColor: return UIColor.black
      }
    }
  }
	
  override func viewDidLoad() {
    let subview = UIView(frame: CGRect(x: 0, y: 0, width: a(.width), height: a(.height))
    view.addSubview(subview)
  }
}

Must have to

• The type of object and the type where used must match.

Benefits

• Convenient constant management
• Convenient duplicate constant management

Source

protocol Constable {
  var object: Any { get }
}

protocol ConstConvertable {
  associatedtype Const: Constable
}

extension ConstConvertable {
  func a<T>(_ value: Const) -> T {
    return value.object as! T
  }
}