ios - Coredata in swift -

hello having issue core data in swift, doesn't show error doesn't print when believe should returning 'joe' + 'pass' in console. please?

import uikit import coredata  class viewcontroller: uiviewcontroller {    override func viewdidload() {     super.viewdidload()     // additional setup after loading view, typically nib.      var appdel:appdelegate = uiapplication.sharedapplication().delegate as! appdelegate      var context:nsmanagedobjectcontext = appdel.managedobjectcontext      var newuser = nsentitydescription.insertnewobjectforentityforname("users", inmanagedobjectcontext: context) nsmanagedobject      newuser.setvalue("joe", forkey: "username")      newuser.setvalue("pass", forkey: "password")      {      try context.save()     } catch let error {         print("couldn't save user data")         print(error)     }      let request = nsfetchrequest(entityname: "users")         request.returnsobjectsasfaults = false      {         var results = try context.executefetchrequest(request)         results = results as! [nsmanagedobject]         if results.count > 0 {         results in results {             print(results)             }}     } catch let error nserror {         print(error)     } }  override func didreceivememorywarning() {     super.didreceivememorywarning()     // dispose of resources can recreated. }   } 

1. you should create own coredata class (as subclass of nsmanagedobject) , create array out of class.

2. specify want print. in case

   newuser.username