深入解析Swift语言中的协议

protocol classa {
  
   var marks: Int { get set }
   var result: Bool { get }
  
   func attendance() -> String
   func markssecured() -> String
  
}

protocol classb: classa {
  
   var present: Bool { get set }
   var subject: String { get set }
   var stname: String { get set }
  
}

class classc: classb {
   var marks = 96
   let result = true
   var present = false
   var subject = "Swift Protocols"
   var stname = "Protocols"
  
   func attendance() -> String {
      return "The \(stname) has secured 99% attendance"
   }
  
   func markssecured() -> String {
      return "\(stname) has scored \(marks)"
   }
}

let studdet = classc()
studdet.stname = "Swift"
studdet.marks = 98
studdet.markssecured()

println(studdet.marks)
println(studdet.result)
println(studdet.present)
println(studdet.subject)
println(studdet.stname)

protocol daysofaweek {
   mutating func print()
}

enum days: daysofaweek {
   case sun, mon, tue, wed, thurs, fri, sat
   mutating func print() {
      switch self {
      case sun:
         self = sun
         println("Sunday")
      case mon:
         self = mon
         println("Monday")
      case tue:
         self = tue
         println("Tuesday")
      case wed:
         self = wed
         println("Wednesday")
      case mon:
         self = thurs
         println("Thursday")
      case tue:
         self = fri
         println("Friday")
      case sat:
         self = sat
         println("Saturday")
      default:
         println("NO Such Day")
      }
   }
}

var res = days.wed
res.print()

class SomeClass: SomeProtocol {
   required init(someParameter: Int) {
      // initializer implementation statements
   }
}

protocol tcpprotocol {
   init(aprot: Int)
}

class tcpClass: tcpprotocol {
   required init(aprot: Int) {
   }
}

protocol tcpprotocol {
   init(no1: Int)
}

class mainClass {
   var no1: Int // local storage
   init(no1: Int) {
      self.no1 = no1 // initialization
   }
}

class subClass: mainClass, tcpprotocol {
   var no2: Int
   init(no1: Int, no2 : Int) {
      self.no2 = no2
      super.init(no1:no1)
   }
   // Requires only one parameter for convenient method
   required override convenience init(no1: Int)  {
      self.init(no1:no1, no2:0)
   }
}
let res = mainClass(no1: 20)
let print = subClass(no1: 30, no2: 50)

println("res is: \(res.no1)")
println("res is: \(print.no1)")
println("res is: \(print.no2)")

protocol Generator {
   typealias members
   func next() -> members?
}

var items = [10,20,30].generate()
while let x = items.next() {
   println(x)
}

for lists in map([1,2,3], {i in i*5}) {
   println(lists)
}

println([100,200,300])
println(map([1,2,3], {i in i*10}))

protocol AgeClasificationProtocol {
   var age: Int { get }
   func agetype() -> String
}

class Person {
   let firstname: String
   let lastname: String
   var age: Int
   init(firstname: String, lastname: String) {
      self.firstname = firstname
      self.lastname = lastname
      self.age = 10
   }
}

extension Person : AgeClasificationProtocol {
   func fullname() -> String {
      var c: String
      c = firstname + " " + lastname
      return c
   }
  
   func agetype() -> String {
      switch age {
      case 0...2:
         return "Baby"
      case 2...12:
         return "Child"
      case 13...19:
         return "Teenager"
      case let x where x > 65:
         return "Elderly"
      default:
         return "Normal"
      }
   }
}

protocol classa {
   var no1: Int { get set }
   func calc(sum: Int)
}

protocol result {
   func print(target: classa)
}

class student2: result {
   func print(target: classa) {
      target.calc(1)
   }
}

class classb: result {
   func print(target: classa) {
      target.calc(5)
   }
}

class student: classa {
   var no1: Int = 10
  
   func calc(sum: Int) {
      no1 -= sum
      println("Student attempted \(sum) times to pass")
     
      if no1 <= 0 {
         println("Student is absent for exam")
      }
   }
}

class Player {
   var stmark: result!
  
   init(stmark: result) {
      self.stmark = stmark
   }
  
   func print(target: classa) {
      stmark.print(target)
   }
}

var marks = Player(stmark: student2())
var marksec = student()

marks.print(marksec)
marks.print(marksec)
marks.print(marksec)
marks.stmark = classb()
marks.print(marksec)
marks.print(marksec)
marks.print(marksec)

protocol tcpprotocol {
   init(no1: Int)
}

class mainClass {
   var no1: Int // local storage
   init(no1: Int) {
      self.no1 = no1 // initialization
   }
}

class subClass: mainClass, tcpprotocol {
   var no2: Int
   init(no1: Int, no2 : Int) {
      self.no2 = no2
      super.init(no1:no1)
   }
   // Requires only one parameter for convenient method
   required override convenience init(no1: Int)  {
      self.init(no1:no1, no2:0)
   }
}

let res = mainClass(no1: 20)
let print = subClass(no1: 30, no2: 50)

println("res is: \(res.no1)")
println("res is: \(print.no1)")
println("res is: \(print.no2)")

protocol stname {
   var name: String { get }
}

protocol stage {
   var age: Int { get }
}

struct Person: stname, stage {
   var name: String
   var age: Int
}

func print(celebrator: protocol<stname, stage>) {
   println("\(celebrator.name) is \(celebrator.age) years old")
}

let studname = Person(name: "Priya", age: 21)
print(studname)

let stud = Person(name: "Rehan", age: 29)
print(stud)

let student = Person(name: "Roshan", age: 19)
print(student)

 import Foundation

@objc protocol rectangle {
   var area: Double { get }
}

@objc class Circle: rectangle {
   let pi = 3.1415927
   var radius: Double
   var area: Double { return pi * radius * radius }
   init(radius: Double) { self.radius = radius }
}

@objc class result: rectangle {
   var area: Double
   init(area: Double) { self.area = area }
}

class sides {
   var rectsides: Int
   init(rectsides: Int) { self.rectsides = rectsides }
}

let objects: [AnyObject] = [Circle(radius: 2.0),result(area: 198),sides(rectsides: 4)]

for object in objects {
   if let objectWithArea = object as? rectangle {
      println("Area is \(objectWithArea.area)")
   } else {
      println("Rectangle area is not defined")
   }
}