garnet/haskell/exe/Main.hs

module Main (main) where

import Data.ByteString
import Data.Word
import Foreign.C
import GarnetRs
import GarnetRs.Safe
import HsBindgen.Runtime.PtrConst
import Unsafe.Coerce

main :: IO ()
main = do
    useAsCString "Haskell" $ hello . unsafeFromPtr
    hello_struct $ convertT T'{a = True, b = 42}
    hello_struct $ convertT T'{a = False, b = 42}
    hello_shape $ convertShape $ Circle 3.14
    hello_shape $ convertShape $ Rectangle 10.0 5.0

data T' = T'
    { a :: Bool
    , b :: Word8
    }
convertT T'{a, b} =
    -- T{a = CBool $ unsafeCoerce @Bool @Word8 a, b}
    T{a = CBool $ fromIntegral $ fromEnum a, b}

data Shape'
    = Circle CDouble
    | Rectangle CDouble CDouble
convertShape = \case
    Circle r -> Shape (Shape_Tag 0) $ set_shape_body_circle $ Circle_Body r
    Rectangle w h -> Shape (Shape_Tag 1) $ set_shape_body_rectangle $ Rectangle_Body w h