Load loadpath.
veristar.list_denote veristar.model_type veristar.model
veristar.basic veristar.compare.
Module Type SPRED_LEMMAS.
Declare Module VSM : VERISTAR_MODEL.
End SPRED_LEMMAS.
Module SPredLemmas (VSM : VERISTAR_MODEL) <: SPRED_LEMMAS
with Module VSM := VSM.
Module VSM := VSM.
(* properties of spred operators *)
Module spred. Section spred.
Variables x y z : spred.
Local Open Scope pred.

Lemma empty_not_singleton: forall c, M.empty <> M.singleton c.