Beer.hs

data Hop = Hop {name :: String, alphaAcid :: Double} deriving (Show)
data BoilTime = BoilTime Int deriving (Show)
data HopAddition = HopAddition Hop BoilTime deriving (Show)
data HomebrewRecipe = HomebrewRecipe [HopAddition] deriving (Show)

recipeIbus :: HomebrewRecipe -> Double
recipeIbus (HomebrewRecipe as) = sum $ map ibus as

ibus :: HopAddition -> Double
ibus x = utilization x * ouncesOfHops * 7490 / 5

utilization :: HopAddition -> Double
utilization a = bignessFactor * boilTimeFactor

bignessFactor :: Double
bignessFactor = 1.65 * 0.000125 ** (wortGravity - 1)

boilTimeFactor :: Double
boilTimeFactor = undefined

wortGravity :: Double
wortGravity = 1.050

ouncesOfHops :: Double
ouncesOfHops = undefined