fact: Definition hausdorffBall (e:Q) (A B: X -> Prop) := 0 <= e /\ hemiMetric e A B /\ hemiMetric e B A.
imports: CoRN.algebra.RSetoid CoRN.logic.Classic CoRN.metric2.Metric CoRN.metric2.Classification Coq.Lists.List Coq.ZArith.ZArith CoRN.model.totalorder.QMinMax CoRN.model.totalorder.QposMinMax