random.idr

data Action = Flower | Upwards | Branch

data RndGen

RndNumGen : Type
RndNumGen = EffM Identity Action [RND] (const [RND])

getRnd : RndNumGen -> (Action, RndNumGen)
getRnd prev =
    let
        (Id action) = run prev
    in
        (action, next)
    where
        next : RndNumGen
        next = do
            prev
            rndSelect' $ [ Flower, Branch, Upwards, Upwards, Upwards ]