getFieldLabels has better error messages

[matthijs/master-project/cλash.git] / clash / CLasH / VHDL / VHDLTools.hs

diff --git a/clash/CLasH/VHDL/VHDLTools.hs b/clash/CLasH/VHDL/VHDLTools.hs
index 0ac3015e3f512533371a150f3d047de00e50da44..ab3360b8126c44950c2f9cabddf71f73f38ef0ee 100644 (file)
--- a/clash/CLasH/VHDL/VHDLTools.hs
+++ b/clash/CLasH/VHDL/VHDLTools.hs
@@ -346,7 +346,8 @@ mkHTypeEither' ty | ty_has_free_tyvars ty = return $ Left $ "\nVHDLTools.mkHType
                   return $ Right $ SizedIType len
                 "Index" -> do
                   bound <- tfp_to_int (ranged_word_bound_ty ty)
-                  return $ Right $ RangedWType bound
+                  -- Upperbound is exclusive, hence the -1
+                  return $ Right $ RangedWType (bound - 1)
                 otherwise ->
                   mkTyConHType tycon args
     Nothing -> return $ Left $ "\nVHDLTools.mkHTypeEither': Do not know what to do with type: " ++ pprString ty
@@ -570,8 +571,8 @@ getFields ::
 getFields htype dc_i = case htype of
   (AggrType name _ fieldss) 
     | dc_i >= 0 && dc_i < length fieldss -> fieldss!!dc_i
-    | otherwise -> error $ "Invalid constructor index: " ++ (show dc_i) ++ ". No such constructor in HType: " ++ (show htype)
-  _ -> error $ "Can't get fields from non-aggregate HType: " ++ show htype
+    | otherwise -> error $ "VHDLTool.getFields: Invalid constructor index: " ++ (show dc_i) ++ ". No such constructor in HType: " ++ (show htype)
+  _ -> error $ "VHDLTool.getFields: Can't get fields from non-aggregate HType: " ++ show htype
 
 -- Finds the field labels for an aggregation type, as VHDLIds.
 getFieldLabels ::
@@ -581,6 +582,17 @@ getFieldLabels ::
   -> [AST.VHDLId]      -- ^ The labels
 getFieldLabels htype dc_i = ((map mkVHDLBasicId) . (map fst)) (getFields htype dc_i)
 
+-- Finds the field label for the constructor field, if any.
+getConstructorFieldLabel ::
+  HType
+  -> Maybe AST.VHDLId
+getConstructorFieldLabel (AggrType _ (Just con) _) =
+       Just $ mkVHDLBasicId (fst con)
+getConstructorFieldLabel (AggrType _ Nothing _) =
+       Nothing
+getConstructorFieldLabel htype =
+       error $ "Can't get constructor field label from non-aggregate HType: " ++ show htype
+
 mktydecl :: (AST.VHDLId, Maybe (Either AST.TypeDef AST.SubtypeIn)) -> Maybe AST.PackageDecItem
 mytydecl (_, Nothing) = Nothing
 mktydecl (ty_id, Just (Left ty_def)) = Just $ AST.PDITD $ AST.TypeDec ty_id ty_def