val normalize:
#pstatus as 'status -> ?delta:int -> NCic.context -> cic_term ->
'status * cic_term
+val are_convertible:
+ #pstatus as 'status -> NCic.context -> cic_term -> cic_term -> 'status * bool
val typeof:
#pstatus as 'status -> NCic.context -> cic_term -> 'status * cic_term
val unify: