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

    The 'GI.GLib.Structs.Data.Data' struct is an opaque data structure to represent a
    [Keyed Data List][glib-Keyed-Data-Lists]. It should only be
    accessed via the following functions.
    -}

    #define ENABLE_OVERLOADING \
           (!defined(__HADDOCK_VERSION__))

    module GI.GLib.Structs.Data
        (

    -- * Exported types
        Data(..)                                ,
        noData                                  ,

        ) where

    import Data.GI.Base.ShortPrelude
    import qualified Data.GI.Base.ShortPrelude as SP
    import qualified Data.GI.Base.Overloading as O
    import qualified Prelude as P

    import qualified Data.GI.Base.Attributes as GI.Attributes
    import qualified Data.GI.Base.ManagedPtr as B.ManagedPtr
    import qualified Data.GI.Base.GError as B.GError
    import qualified Data.GI.Base.GVariant as B.GVariant
    import qualified Data.GI.Base.GValue as B.GValue
    import qualified Data.GI.Base.GParamSpec as B.GParamSpec
    import qualified Data.GI.Base.CallStack as B.CallStack
    import qualified Data.Text as T
    import qualified Data.ByteString.Char8 as B
    import qualified Data.Map as Map
    import qualified Foreign.Ptr as FP

    -- | Memory-managed wrapper type.
    newtype Data = Data (ManagedPtr Data)
    -- XXX Wrapping a foreign struct/union with no known destructor or size, leak?
    instance WrappedPtr Data where
        wrappedPtrCalloc = return nullPtr
        wrappedPtrCopy = return
        wrappedPtrFree = Nothing

    -- | A convenience alias for `Nothing` :: `Maybe` `Data`.
    noData :: Maybe Data
    noData = Nothing

    #if ENABLE_OVERLOADING
    instance O.HasAttributeList Data
    type instance O.AttributeList Data = DataAttributeList
    type DataAttributeList = ('[ ] :: [(Symbol, *)])
    #endif

    #if ENABLE_OVERLOADING
    type family ResolveDataMethod (t :: Symbol) (o :: *) :: * where
        ResolveDataMethod l o = O.MethodResolutionFailed l o

    instance (info ~ ResolveDataMethod t Data, O.MethodInfo info Data p) => O.IsLabelProxy t (Data -> p) where
        fromLabelProxy _ = O.overloadedMethod (O.MethodProxy :: O.MethodProxy info)

    #if MIN_VERSION_base(4,9,0)
    instance (info ~ ResolveDataMethod t Data, O.MethodInfo info Data p) => O.IsLabel t (Data -> p) where
    #if MIN_VERSION_base(4,10,0)
        fromLabel = O.overloadedMethod (O.MethodProxy :: O.MethodProxy info)
    #else
        fromLabel _ = O.overloadedMethod (O.MethodProxy :: O.MethodProxy info)
    #endif
    #endif

    #endif