proposition: Lemma decidable_excl : forall {A : Type} (P : Ensemble A) (P_dec : DecideableEnsemble P), (forall (a: A), P a \/ ~ P a).
proof: Proof. intros ??? a. destruct (dec a) eqn:eqdec; [ rewrite dec_decides_P in eqdec | rewrite Decides_false in eqdec ]; intuition. Qed.
imports: Fiat.QueryStructure.Specification.Representation.QueryStructureNotations Fiat.QueryStructure.Specification.Operations.Query Coq.Lists.List Coq.Arith.Compare_dec Coq.Bool.Bool Coq.Strings.String Fiat.Common.BoolFacts Fiat.Common.List.PermutationFacts Fiat.Common.List.ListMorphisms Fiat.QueryStructure.Specification.Operations.FlattenCompList Fiat.Common.Ensembles.EnsembleListEquivalence Fiat.QueryStructure.Implementation.Operations.General.QueryRefinements Fiat.Common.IterateBoundedIndex Fiat.Common.List.ListFacts Fiat.Common.LogicFacts Fiat.Common.DecideableEnsembles Fiat.Computation.Refinements.Iterate_Decide_Comp Fiat.Computation.Refinements.General Fiat.QueryStructure.Specification.Constraints.tupleAgree Fiat.QueryStructure.Specification.Operations.Mutate