@class NSObject; @protocol OS_dispatch_group, OS_dispatch_queue, NUFaceDetectionResult; @interface PIFaceObservationCache : NSObject { NSObject<OS_dispatch_group> *_group; NSObject<OS_dispatch_queue> *_queue; id<NUFaceDetectionResult> _result; } + (id)faceRequestWithRequest:(id)a0; - (id)init; - (void).cxx_destruct; - (void)submit:(id)a0 response:(id /* block */)a1; - (id)submitSynchronous:(id)a0 error:(out id *)a1; @end