ios - TableView definition conflict with previous using CoreData in Mutable array -

i trying access coredata , putting tableview have data mutable array when try access tableview got error.

my code follows:

import uikit import coredata  class tableview: uiviewcontroller, uitableviewdelegate {      @iboutlet weak var tableview: uitableview!      override func viewdidload() {          var desc_arr: [string] = []         var amt_arr: [string] = []          let appdel: appdelegate = uiapplication.sharedapplication().delegate as! appdelegate         let context: nsmanagedobjectcontext = appdel.managedobjectcontext         let request = nsfetchrequest(entityname: "expense")         request.returnsobjectsasfaults = false          {             let results = try context.executefetchrequest(request)              if results.count > 0 {                  result in results as! [nsmanagedobject] {                      if let desc = result.valueforkey("desc") as? string {                         print(desc)                         desc_arr.append(desc)                     }                      if let amt = result.valueforkey("amt") as? string{                         print(amt)                         amt_arr.append(amt)                     }                 }             }         } catch {             print("fetch failed")         }          print(desc_arr)         print(amt_arr)          func tableview(tableview: uitableview, numberofrowsinsection section: int) -> int {             return desc_arr.count         }          override func tableview(tableview: uitableview, cellforrowatindexpath indexpath: nsindexpath) -> uitableviewcell {             let cell = uitableviewcell(style: uitableviewcellstyle.default, reuseidentifier: "cell")             cell.textlabel?.text = desc_arr[indexpath.row]             return cell         }     } }