gistfile1.swift

//: Playground - noun: a place where people can play

import UIKit

protocol PlaceholderText : class, UITextInputTraits {
	var placeholder: String? { get set }
}

extension UITextField: PlaceholderText { }
extension UITextView: PlaceholderText {
	var placeholder: String? {
		get { return "" }
		set { }
	}
}

var textFieldOrView: PlaceholderText = UITextView()
textFieldOrView.placeholder = "Placeholder"
textFieldOrView.autocapitalizationType = .Words // Compilation Error: Cannot assign to the result of this expression