{-# LANGUAGE CPP, PackageImports #-} #if __GLASGOW_HASKELL__ >= 701 {-# LANGUAGE Safe #-} #endif module Foreign.C.Types ( -- * Representations of C types -- $ctypes -- ** Integral types -- | These types are are represented as @newtype@s of -- types in "Data.Int" and "Data.Word", and are instances of -- 'Prelude.Eq', 'Prelude.Ord', 'Prelude.Num', 'Prelude.Read', -- 'Prelude.Show', 'Prelude.Enum', 'Storable', -- 'Prelude.Bounded', 'Prelude.Real', 'Prelude.Integral' and -- 'Bits'. CChar, CSChar, CUChar , CShort, CUShort, CInt, CUInt , CLong, CULong , CPtrdiff, CSize, CWchar, CSigAtomic , CLLong, CULLong , CIntPtr, CUIntPtr , CIntMax, CUIntMax -- ** Numeric types -- | These types are are represented as @newtype@s of basic -- foreign types, and are instances of -- 'Prelude.Eq', 'Prelude.Ord', 'Prelude.Num', 'Prelude.Read', -- 'Prelude.Show', 'Prelude.Enum' and 'Storable'. , CClock, CTime -- ** Floating types -- | These types are are represented as @newtype@s of -- 'Prelude.Float' and 'Prelude.Double', and are instances of -- 'Prelude.Eq', 'Prelude.Ord', 'Prelude.Num', 'Prelude.Read', -- 'Prelude.Show', 'Prelude.Enum', 'Storable', -- 'Prelude.Real', 'Prelude.Fractional', 'Prelude.Floating', -- 'Prelude.RealFrac' and 'Prelude.RealFloat'. , CFloat, CDouble -- GHC doesn't support CLDouble yet #ifdef HASKELL_REPORT , CLDouble #endif -- ** Other types -- Instances of: Eq and Storable , CFile, CFpos, CJmpBuf ) where import "base" Foreign.C.Types {- $ctypes These types are needed to accurately represent C function prototypes, in order to access C library interfaces in Haskell. The Haskell system is not required to represent those types exactly as C does, but the following guarantees are provided concerning a Haskell type @CT@ representing a C type @t@: * If a C function prototype has @t@ as an argument or result type, the use of @CT@ in the corresponding position in a foreign declaration permits the Haskell program to access the full range of values encoded by the C type; and conversely, any Haskell value for @CT@ has a valid representation in C. * @'sizeOf' ('Prelude.undefined' :: CT)@ will yield the same value as @sizeof (t)@ in C. * @'alignment' ('Prelude.undefined' :: CT)@ matches the alignment constraint enforced by the C implementation for @t@. * The members 'peek' and 'poke' of the 'Storable' class map all values of @CT@ to the corresponding value of @t@ and vice versa. * When an instance of 'Prelude.Bounded' is defined for @CT@, the values of 'Prelude.minBound' and 'Prelude.maxBound' coincide with @t_MIN@ and @t_MAX@ in C. * When an instance of 'Prelude.Eq' or 'Prelude.Ord' is defined for @CT@, the predicates defined by the type class implement the same relation as the corresponding predicate in C on @t@. * When an instance of 'Prelude.Num', 'Prelude.Read', 'Prelude.Integral', 'Prelude.Fractional', 'Prelude.Floating', 'Prelude.RealFrac', or 'Prelude.RealFloat' is defined for @CT@, the arithmetic operations defined by the type class implement the same function as the corresponding arithmetic operations (if available) in C on @t@. * When an instance of 'Bits' is defined for @CT@, the bitwise operation defined by the type class implement the same function as the corresponding bitwise operation in C on @t@. -}