module Dodge.Base.Arithmetic where
import MaybeHelp

decreaseToZero :: Int -> Int
decreaseToZero = max 0 . subtract 1

decreaseToNothing' :: (Num a, Ord a) => Maybe' a -> Maybe' a
decreaseToNothing' ma = case ma of
    Just' x | x > 0 -> Just' (x - 1)
    _ -> Nothing'