rgDF :: (String -> DynFlags -> DynFlags) -> String -> OptKind (CmdLineP DynFlags)
hasArgDF fn deprec = HasArg (\s -> do upd (fn s)
                                      deprecate deprec)

se
hasArgDF :: (String -> DynFlags -> DynFlags) -> String -> OptKind (CmdLineP DynFlags)
hasArgDF fn deprec = HasArg (\s -> do upd (fn s)
                                      deprecate deprec)
hasArgDF fn deprec = HasArg (\s -> do upd (fn s)
                                      deprecate deprec)