val get_clears:
Cic.context -> Cic.term -> (Cic.term * Cic.term) option ->
Cic.context * string list
val clear: Cic.context -> string -> Cic.context
val get_clears:
Cic.context -> Cic.term -> (Cic.term * Cic.term) option ->
Cic.context * string list
val clear: Cic.context -> string -> Cic.context