FloatIEEE754.hs


{- |
Copyright  : Will Thompson, Iñaki García Etxebarria and Jonas Platte
License    : LGPL-2.1
Maintainer : Iñaki García Etxebarria (garetxe@gmail.com)
-}

module GI.GLib.Unions.FloatIEEE754
    ( 

-- * Exported types
    FloatIEEE754(..)                        ,
    newZeroFloatIEEE754                     ,
    noFloatIEEE754                          ,


 -- * Properties
-- ** VFloat
    floatIEEE754ReadVFloat                  ,




    ) where

import Prelude ()
import Data.GI.Base.ShortPrelude

import qualified Data.Text as T
import qualified Data.ByteString.Char8 as B
import qualified Data.Map as Map

import GI.GLib.Types
import GI.GLib.Callbacks

newtype FloatIEEE754 = FloatIEEE754 (ForeignPtr FloatIEEE754)
-- | Construct a `FloatIEEE754` struct initialized to zero.
newZeroFloatIEEE754 :: MonadIO m => m FloatIEEE754
newZeroFloatIEEE754 = liftIO $ callocBytes 4 >>= wrapPtr FloatIEEE754

noFloatIEEE754 :: Maybe FloatIEEE754
noFloatIEEE754 = Nothing

floatIEEE754ReadVFloat :: FloatIEEE754 -> IO Float
floatIEEE754ReadVFloat s = withManagedPtr s $ \ptr -> do
    val <- peek (ptr `plusPtr` 0) :: IO CFloat
    let val' = realToFrac val
    return val'

type family ResolveFloatIEEE754Method (t :: Symbol) (o :: *) :: * where
    ResolveFloatIEEE754Method l o = MethodResolutionFailed l o

instance (info ~ ResolveFloatIEEE754Method t FloatIEEE754, MethodInfo info FloatIEEE754 p) => IsLabelProxy t (FloatIEEE754 -> p) where
    fromLabelProxy _ = overloadedMethod (MethodProxy :: MethodProxy info)

#if MIN_VERSION_base(4,9,0)
instance (info ~ ResolveFloatIEEE754Method t FloatIEEE754, MethodInfo info FloatIEEE754 p) => IsLabel t (FloatIEEE754 -> p) where
    fromLabel _ = overloadedMethod (MethodProxy :: MethodProxy info)
#endif