modifyR :: (StdGen -> (a,StdGen)) -> CommandGen a
modifyR f = modifyCGS (\s -> let (a,g) = f (rG s) in (a,s { rG = g}) )
modifyR :: (StdGen -> (a,StdGen)) -> CommandGen a
modifyR f = modifyCGS (\s -> let (a,g) = f (rG s) in (a,s { rG = g}) )
modifyR f = modifyCGS (\s -> let (a,g) = f (rG s) in (a,s { rG = g}) )