Demonstrate building a ByteString from heterogenous Storable types.

StorableBinary.hs

{-# LANGUAGE ScopedTypeVariables #-}
import Data.Binary.Builder
import Data.Binary.Builder.Internal
import Foreign.Ptr (castPtr)
import Foreign.Storable (Storable(sizeOf,poke))

-- For testing
import Linear
import Data.ByteString.Lazy (ByteString)
import Data.Monoid ((<>))

store :: forall a. Storable a => a -> Builder
store x = writeN (sizeOf (undefined::a)) (flip poke x . castPtr)

-- Testing
data Foo = Foo (V2 Float) (V3 Double)

fooBytes :: Foo -> ByteString
fooBytes (Foo bar baz) = toLazyByteString $ store bar <> store baz