swift - Lazy loading variable error -


i writing program involves core data. created class variable context , entity , have code written this: 

class persistencymanager {      var context : nsmanagedobjectcontext{         let appdelegate = uiapplication.sharedapplication().delegate as! appdelegate         let localcontext = appdelegate.managedobjectcontext         return localcontext     }     var userentity : nsentitydescription {         let entity = nsentitydescription.entityforname(entitynames.user, inmanagedobjectcontext: context)         return entity!      }       struct entitynames {         private static let user = "user"         private static let category = "category"     } }

everything far works fine, want "lazy"ly load userentity

like : 

   lazy var userentity : nsentitydescription = {         let entity = nsentitydescription.entityforname(entitynames.user, inmanagedobjectcontext: context)         return entity!      }()

but when do, error: "instance member 'context' cannot used on type 'persistency manager' "

what doing wrong? how can achieve goal?

thank you!

try let entity = nsentitydescription.entityforname(entitynames.user, inmanagedobjectcontext: self.context)

note i'm using self.context instead of context. builds me in playground.


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