(* We use evalDist as the probability measure.  Instead of supplying an event on the return type, we expect the computation to test for the occurrence of the event.  *)
Notation "'Pr' [ c  ] " := (evalDist c true) (at level 20).

Lemma evalDist_le_1 : forall (A : Set)(c : Comp A) a, evalDist c a <= 1.