stan

stan copied to clipboard

Advice to use newtypes in data types with multiple fields with the same type:

data Params = Params
    { height :: !Double  -- ^ in cmeters
    , weight :: !Double -- ^ in kgs
    }

replace with

data Params = Params
    { height :: !Cm 
    , weight :: !Kg
    }

newtype Cm = {unCm :: Double}
newtype Kg = {unKg :: Double}

We discussed that this is not always desirable to have this feature enabled by default. So it will be an opt-in feature which you may want to enable everywhere or in some specific places.