1/1: Building Door (Door.idr)
Main>               (y @@ res) => ?now_4

Main>               (True @@ d) => ?now_4
              (False @@ d) => ?now_5

Main>  0 m : Type -> Type
   x : Integer
 1 d : Door Open
 0 r : Res Bool (\r => (Door (if r then Open else Closed)))
-------------------------------------
now_2 : Use Many m ()
Main>  0 m : Type -> Type
   x : Integer
 1 d : Door Closed
 0 r : Res Bool (\r => (Door (if r then Open else Closed)))
-------------------------------------
now_3 : Use Many m ()
Main> Bye for now!