-(* also adds them to the Db *)
-val close_coercion_graph:
- CoercDb.coerc_carr -> CoercDb.coerc_carr -> UriManager.uri ->
- (UriManager.uri * Cic.obj * CicUniv.universe_graph) list
+val is_a_coercion: Cic.term -> bool
+val source_of: Cic.term -> Cic.term
+val target_of: Cic.term -> Cic.term