<<>> <> <> <> <> <<>> DIRECTORY ViewerClasses; ViewerAbort: CEDAR DEFINITIONS ~ BEGIN Viewer: TYPE ~ ViewerClasses.Viewer; CallWithAbortEnabled: PROC [viewer: Viewer, action: PROC]; <> CallWithAbortAndCallback: PROC [viewer: Viewer, action: PROC, callback: PROC [REF], data: REF]; <> <<>> END.