#define _REENTRANT 1 (needed to get the right errno on some OSs)

[ghc-base.git] / include / Typeable.h

diff --git a/include/Typeable.h b/include/Typeable.h
index 5486e1e..b4ea475 100644 (file)
--- a/include/Typeable.h
+++ b/include/Typeable.h
@@ -1,25 +1,64 @@
 /* ----------------------------------------------------------------------------
  * Macros to help make Typeable instances.
+ *
+ * INSTANCE_TYPEABLEn(tc,tcname,"tc") defines
+ *
+ *     instance Typeable/n/ tc
+ *     instance Typeable a => Typeable/n-1/ (tc a)
+ *     instance (Typeable a, Typeable b) => Typeable/n-2/ (tc a b)
+ *     ...
+ *     instance (Typeable a1, ..., Typeable an) => Typeable (tc a1 ... an)
  * -------------------------------------------------------------------------- */
 
+#ifndef TYPEABLE_H
+#define TYPEABLE_H
+
 #define INSTANCE_TYPEABLE0(tycon,tcname,str) \
 tcname = mkTyCon str; \
-instance Typeable tycon where { typeOf _ = mkAppTy tcname [] }
+instance Typeable tycon where { typeOf _ = mkTyConApp tcname [] }
+
+#ifdef __GLASGOW_HASKELL__
+
+/* For GHC, the extra instances follow from general instance declarations
+ * defined in Data.Typeable. */
 
 #define INSTANCE_TYPEABLE1(tycon,tcname,str) \
 tcname = mkTyCon str; \
-instance Typeable a => Typeable (tycon a) where { \
-  typeOf x = mkAppTy tcname [typeOf ((undefined :: tycon a -> a) x) ] }
+instance Typeable1 tycon where { typeOf1 _ = mkTyConApp tcname [] }
 
 #define INSTANCE_TYPEABLE2(tycon,tcname,str) \
 tcname = mkTyCon str; \
+instance Typeable2 tycon where { typeOf2 _ = mkTyConApp tcname [] }
+
+#define INSTANCE_TYPEABLE3(tycon,tcname,str) \
+tcname = mkTyCon str; \
+instance Typeable3 tycon where { typeOf3 _ = mkTyConApp tcname [] }
+
+#else /* !__GLASGOW_HASKELL__ */
+
+#define INSTANCE_TYPEABLE1(tycon,tcname,str) \
+tcname = mkTyCon str; \
+instance Typeable1 tycon where { typeOf1 _ = mkTyConApp tcname [] }; \
+instance Typeable a => Typeable (tycon a) where { typeOf = typeOfDefault }
+
+#define INSTANCE_TYPEABLE2(tycon,tcname,str) \
+tcname = mkTyCon str; \
+instance Typeable2 tycon where { typeOf2 _ = mkTyConApp tcname [] }; \
+instance Typeable a => Typeable1 (tycon a) where { \
+  typeOf1 = typeOf1Default }; \
 instance (Typeable a, Typeable b) => Typeable (tycon a b) where { \
-  typeOf x = mkAppTy tcname [typeOf ((undefined :: tycon a b -> a) x), \
-                            typeOf ((undefined :: tycon a b -> b) x)] }
+  typeOf = typeOfDefault }
 
 #define INSTANCE_TYPEABLE3(tycon,tcname,str) \
 tcname = mkTyCon str; \
-instance (Typeable a, Typeable b, Typeable c) => Typeable (tycon a b c) where {\
-  typeOf a = mkAppTy tcname [typeOf ((undefined :: tycon a b c -> a) a), \
-                            typeOf ((undefined :: tycon a b c -> b) a), \
-                            typeOf ((undefined :: tycon a b c -> c) a)] }
+instance Typeable3 tycon where { typeOf3 _ = mkTyConApp tcname [] }; \
+instance Typeable a => Typeable2 (tycon a) where { \
+  typeOf2 = typeOf2Default }; \
+instance (Typeable a, Typeable b) => Typeable1 (tycon a b) where { \
+  typeOf1 = typeOf1Default }; \
+instance (Typeable a, Typeable b, Typeable c) => Typeable (tycon a b c) where { \
+  typeOf = typeOfDefault }
+
+#endif /* !__GLASGOW_HASKELL__ */
+
+#endif