Module Fragment.Oriented

type fragment := t
type t

A fragment and an orientation. Can be thought of as a tree node -- with its extensions as children and it's retraction as parent.

val fragment : t -> fragment
val orient : t -> Orientation.t
val first : t -> Location.t
val retract : t -> t option
val retract_by : t -> n:int -> t option
val one_frame_extensions : t -> (Location.t, t) Core.List.Assoc.t
val has_extensions : t -> bool
val extend : t -> Location.t -> t option
module Debug : sig ... end