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{- --------------------------------------------------------------------------
// Dirty CPP hackery for CTypes/CTypesISO
//
// (c) The FFI task force, 2000
// --------------------------------------------------------------------------
-}
#ifndef CTYPES__H
#define CTYPES__H
{-
// As long as there is no automatic derivation of classes for newtypes we resort
// to extremely dirty cpp-hackery. :-P Some care has to be taken when the
// macros below are modified, otherwise the layout rule will bite you.
-}
-- // GHC can derive any class for a newtype, so we make use of that here...
#define ARITHMETIC_CLASSES Eq,Ord,Num,Enum,Storable,Real
#define INTEGRAL_CLASSES Bounded,Integral,Bits,FiniteBits
#define FLOATING_CLASSES Fractional,Floating,RealFrac,RealFloat
#define ARITHMETIC_TYPE(T,B) \
newtype T = T B deriving (ARITHMETIC_CLASSES); \
INSTANCE_READ(T,B); \
INSTANCE_SHOW(T,B);
#define INTEGRAL_TYPE(T,B) \
newtype T = T B deriving (ARITHMETIC_CLASSES, INTEGRAL_CLASSES); \
INSTANCE_READ(T,B); \
INSTANCE_SHOW(T,B);
#define INTEGRAL_TYPE_WITH_CTYPE(T,THE_CTYPE,B) \
newtype {-# CTYPE "THE_CTYPE" #-} T = T B deriving (ARITHMETIC_CLASSES, INTEGRAL_CLASSES); \
INSTANCE_READ(T,B); \
INSTANCE_SHOW(T,B);
#define FLOATING_TYPE(T,B) \
newtype T = T B deriving (ARITHMETIC_CLASSES, FLOATING_CLASSES); \
INSTANCE_READ(T,B); \
INSTANCE_SHOW(T,B);
#define INSTANCE_READ(T,B) \
instance Read T where { \
readsPrec = unsafeCoerce# (readsPrec :: Int -> ReadS B); \
readList = unsafeCoerce# (readList :: ReadS [B]); }
#define INSTANCE_SHOW(T,B) \
instance Show T where { \
showsPrec = unsafeCoerce# (showsPrec :: Int -> B -> ShowS); \
show = unsafeCoerce# (show :: B -> String); \
showList = unsafeCoerce# (showList :: [B] -> ShowS); }
#endif
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