sig
type path = Region.offset list
and offset = Oindex of Lang.F.term | Ofield of Lang.field
val access : Lang.F.term -> Region.path -> Lang.F.term
val update : Lang.F.term -> Region.path -> Lang.F.term -> Lang.F.term
type rpath = Region.roffset list
and roffset = Rindex of Vset.set | Rfield of Lang.field
type region
val empty : Region.region
val full : Region.region
val path : Region.path -> Region.region
val rpath : Region.rpath -> Region.region
val merge : Region.region -> Region.region -> Region.region
val disjoint : Region.region -> Region.region -> Lang.F.pred
val subset : Region.region -> Region.region -> Lang.F.pred
val equal_but :
Lang.F.tau -> Region.region -> Lang.F.term -> Lang.F.term -> Lang.F.pred
val vars : Region.region -> Lang.F.Vars.t
val occurs : Lang.F.var -> Region.region -> bool
val pretty : Stdlib.Format.formatter -> Region.region -> unit
end