SwiftGenericType.swift

///
/// Author : Gaurav D. Sharma
/// Run on Swift 3.0 
/// IBM swift sandbox : https://swiftlang.ng.bluemix.net/#/repl
///

////    Are you using ObjectMapper for model mapping in swift.
////    Object creation like Mapper<T>().map(jsonString)
////    And you are irritaed with the type name passing and syntex memorization 
//// 
////    what about below code a cleaner approach to make it
//      public func GetModelObject<T: Mappable>(type: T.Type, jsonString: String) -> T? {
//          return Mapper<T>().map(jsonString)
//      }
////
////
//      GetModelObject(type:UserModel.self, jsonString: json)
////

////---- Below is the whole discuss about this
//   public func get<T: Pro1>(type: T.Type) {
//          GenericClass<T>().printObj() 
//  }

//------------------------- TEST 1 -------------------------
public protocol Pro1 {
    init()
    var name: String { get }
}

public class Class1 : Pro1 {
    required public init() {}
    public var name: String { return "Class 1" }
}

public class Class2 : Class1 {
   override public var name: String { return "Class 2" }
}

public class GenericClass<T: Pro1> {
    public func printObj() { print(T().name) }
}

//------------------------- TEST 2 -------------------------

public protocol Pro2 {
    static func get<T : Pro1>(type: T.Type) 
}

extension Pro1 where Self: Pro2 {
    public static func get<T : Pro1>(type: T.Type) {
        GenericClass<T>().printObj()
    }
}

public class Class3 : Class1, Pro2 {
    override public var name: String { return "Class 3" }
}

public class Class4 : Class3 {
    override public var name: String { return "Class 4" }
}


//-- Desirable Method : Here Magic happens
public func get<T: Pro1>(type: T.Type) {
   GenericClass<T>().printObj() 
}

//----------------------------------------------------------------
public func test1() {
    GenericClass<Class1>().printObj() // Class 1
    GenericClass<Class2>().printObj() // Class 2
}
test1()

//----------------------------------------------------------------
public func test2() {
    Class3.get(type: Class3.self)  // Class 3
    Class4.get(type: Class4.self)  // Class4
    
    // -- Gives undesirable output; 
    // - Type mistaken pass; so not recommended way
    // - No impact on the call of class method.
    Class3.get(type: Class4.self)  // Class 4 ; Desired Class3
    Class4.get(type: Class3.self)  // Class 3 ; Desired Class4 
    
    // Much better and cleaner way [recommended]
    get(type: Class3.self) // Class 3
    get(type: Class4.self) // Class 4
}
test2()