Add Error extension instead of NSError for Workaround; NSError extension returns a type which conforms to Error protocol

RxCocoa/Common/Observables/NSObject+Rx.swift

@@ -126,10 +126,6 @@ extension NSObject {
      - returns: Observable sequence of object deallocating events.
      */
     public func rx_sentMessage(_ selector: Selector) -> Observable<[AnyObject]> {
-        return Observable.create { _ in
-            return AnonymousDisposable {}
-        }
-        /*
         return rx_synchronized {
             // in case of dealloc selector replay subject behavior needs to be used
             if selector == deallocSelector {
@@ -164,7 +160,7 @@ extension NSObject {
 
             subject.targetImplementation = targetImplementation
             return subject.asObservable()
-        }*/
+        }
     }
 
     /**
@@ -178,10 +174,6 @@ extension NSObject {
     - returns: Observable sequence of object deallocating events.
     */
     public var rx_deallocating: Observable<()> {
-        return Observable.create { _ in
-            return AnonymousDisposable {}
-        }
-        /*
         return rx_synchronized {
 
             let subject: DeallocatingObservable
@@ -210,7 +202,7 @@ extension NSObject {
 
             subject.targetImplementation = targetImplementation!
             return subject.asObservable()
-        }*/
+        }
     }
 #endif
 }

RxCocoa/Common/RxCocoa.swift

@@ -296,16 +296,18 @@ let delegateNotSet = "Delegate not set"
 
 // MARK: Conversions `NSError` > `RxCocoaObjCRuntimeError`
 
-extension NSError {
+extension Error {
     func rxCocoaErrorForTarget(_ target: AnyObject) -> RxCocoaObjCRuntimeError {
-        if domain == RXObjCRuntimeErrorDomain {
-            let errorCode = RXObjCRuntimeError(rawValue: self.code) ?? .unknown
-
+        let error = self as NSError
+        
+        if error.domain == RXObjCRuntimeErrorDomain {
+            let errorCode = RXObjCRuntimeError(rawValue: error.code) ?? .unknown
+            
             switch errorCode {
             case .unknown:
                 return .unknown(target: target)
             case .objectMessagesAlreadyBeingIntercepted:
-                let isKVO = (self.userInfo[RXObjCRuntimeErrorIsKVOKey] as? NSNumber)?.boolValue ?? false
+                let isKVO = (error.userInfo[RXObjCRuntimeErrorIsKVOKey] as? NSNumber)?.boolValue ?? false
                 return .objectMessagesAlreadyBeingIntercepted(target: target, interceptionMechanism: isKVO ? .kvo : .unknown)
             case .selectorNotImplemented:
                 return .selectorNotImplemented(target: target)
@@ -323,7 +325,7 @@ extension NSError {
                 return .observingMessagesWithUnsupportedReturnType(target: target)
             }
         }
-
+        
         return RxCocoaObjCRuntimeError.unknown(target: target)
     }
 }