sig
type t
val compare : Sig.EDGE.t -> Sig.EDGE.t -> int
type vertex
val src : Sig.EDGE.t -> Sig.EDGE.vertex
val dst : Sig.EDGE.t -> Sig.EDGE.vertex
type label
val create :
Sig.EDGE.vertex -> Sig.EDGE.label -> Sig.EDGE.vertex -> Sig.EDGE.t
val label : Sig.EDGE.t -> Sig.EDGE.label
end