val refresh_status: status -> status
-val crg_of_txt: (status -> 'a) -> (status -> Crg.entity -> 'a) ->
- status -> Txt.command -> 'a
+val crg_of_txt: (status -> 'a) -> (status -> Crg.entity -> 'a) ->
+ (Txt.command -> unit) -> status -> Txt.command -> 'a