Module type Imperative.S

module type S = sig .. end

module Concrete: 
functor (V : Sig.COMPARABLE) -> Sig.I  with type V.t = V.t and type V.label = V.t and type E.t = V.t * V.t

module Abstract: 
functor (V : Sig.ANY_TYPE) -> Sig.IM  with type V.label = V.t and type E.label = unit

module ConcreteLabeled: 
functor (V : Sig.COMPARABLE) -> 
functor (E : Sig.ORDERED_TYPE_DFT) -> Sig.I  with type V.t = V.t and type V.label = V.t 
	    and type E.t = V.t * E.t * V.t and type E.label = E.t

module AbstractLabeled: 
functor (V : Sig.ANY_TYPE) -> 
functor (E : Sig.ORDERED_TYPE_DFT) -> Sig.IM  with type V.label = V.t and type E.label = E.t