Set Warnings "-extraction-opaque-accessed,-extraction".
Set Warnings "-notation-overridden,-parsing".
GenLow GenLowInterface
GenHighImpl GenHighInterface
RandomQC Tactics Sets.
Set Bullet Behavior "Strict Subproofs".
Module Import GenHigh := GenHighImpl.Impl GenLow.

Lemma oneOf_freq {A} (g : G A) (gs : list (G A)) size :
semGenSize (oneOf (g ;; gs)) size <-->
semGenSize (freq ((1, g) ;; map (fun x => (1, x)) gs)) size.