swift - How do I implement this protocol in struct -

i'm new swift , want create abstract factory db access. here protocol

protocol idaofactory {   associatedtype dao: idao    func createaccountdao<dao: iaccountdao>() -> dao }  struct realmfactory: idaofactory {  }  protocol idao {    associatedtype t    func save(object: t) }  protocol iaccountdao : idao {  }  struct accountdaorealm: iaccountdao {  } 

how implement idaofactory in struct realmfactory , iaccountdao in struct accountdaorealm? can help?

generics in swift have many restrictions when used in protocols , implemented in struct. let's wait until swift 3 :)

i use protocols , derived classes or generics classes mixing protocols generics , structs makes headache in swift 2 (c# generics in more convenient)

i played code in playground, here is

protocol idaofactory {     associatedtype dao: idao      func createaccountdao<dao: iaccountdao>() -> dao }  protocol idao {     init()     associatedtype t     func save(object: t) }  protocol iaccountdao : idao {     init() }  public class accountdaorealm: iaccountdao {     var data: string = ""      required public init() {         data = "data"     }      func save(object: accountdaorealm) {         //do save     } }  let accountdaorealm = accountdaorealm()  //as see accountdaorealm constructed without error  struct realmfactory: idaofactory {     func createaccountdao<accountdaorealm>() -> accountdaorealm {         return  accountdaorealm() //but here constructor gives error     } }