+
+-- This function returns the primitive type associated with the boxed
+-- type argument to a foreign export (eg. Int ==> Int#). It assumes
+-- that all the types we are interested in have a single constructor
+-- with a single primitive-typed argument, which is true for all of the legal
+-- foreign export argument types (see TcType.legalFEArgTyCon).
+getPrimTyOf :: Type -> Type
+getPrimTyOf ty =
+ case splitProductType_maybe (repType ty) of
+ Just (_, _, data_con, [prim_ty]) ->
+ ASSERT(dataConSourceArity data_con == 1)
+ ASSERT2(isUnLiftedType prim_ty, ppr prim_ty)
+ prim_ty
+ _other -> pprPanic "DsForeign.getPrimTyOf" (ppr ty)