Clarify error message (Trac #3805)

[ghc-hetmet.git] / compiler / rename / RnNames.lhs

diff --git a/compiler/rename/RnNames.lhs b/compiler/rename/RnNames.lhs
index 8037449..7d367c7 100644 (file)
--- a/compiler/rename/RnNames.lhs
+++ b/compiler/rename/RnNames.lhs
@@ -580,10 +580,10 @@ filterImports iface decl_spec (Just (want_hiding, import_items)) all_avails
     lookup_ie opt_typeFamilies ie 
       = let bad_ie = Failed (badImportItemErr iface decl_spec ie)
 
-            lookup_name rdrName = 
-                case lookupOccEnv occ_env (rdrNameOcc rdrName) of
-                   Nothing -> bad_ie
-                   Just n  -> return n
+            lookup_name rdr 
+             | isQual rdr = Failed (qualImportItemErr rdr)
+              | Just nm <- lookupOccEnv occ_env (rdrNameOcc rdr) = return nm
+              | otherwise                                        = bad_ie
         in
         case ie of
          IEVar n -> do
@@ -722,7 +722,7 @@ gresFromIE decl_spec (L loc ie, avail)
 mkChildEnv :: [GlobalRdrElt] -> NameEnv [Name]
 mkChildEnv gres = foldr add emptyNameEnv gres
     where
-       add (GRE { gre_name = n, gre_par = ParentIs p }) env = extendNameEnv_C (++) env p [n]
+       add (GRE { gre_name = n, gre_par = ParentIs p }) env = extendNameEnv_Acc (:) singleton env p n
        add _                                            env = env
 
 findChildren :: NameEnv [Name] -> Name -> [Name]
@@ -1304,20 +1304,20 @@ isImpAll _other                         = False
 
 \begin{code}
 warnUnusedImport :: ImportDeclUsage -> RnM ()
-warnUnusedImport (L loc decl, used, unused) 
-  | Just (False,[]) <- ideclHiding decl 
-               = return ()            -- Do not warn for 'import M()'
+warnUnusedImport (L loc decl, used, unused)
+  | Just (False,[]) <- ideclHiding decl
+                = return ()            -- Do not warn for 'import M()'
   | null used   = addWarnAt loc msg1   -- Nothing used; drop entire decl
-  | null unused = return ()           -- Everything imported is used; nop
+  | null unused = return ()            -- Everything imported is used; nop
   | otherwise   = addWarnAt loc msg2   -- Some imports are unused
   where
     msg1 = vcat [pp_herald <+> quotes pp_mod <+> pp_not_used,
-                nest 2 (ptext (sLit "except perhaps to import instances from")
-                                  <+> quotes pp_mod),
-                ptext (sLit "To import instances alone, use:") 
-                                  <+> ptext (sLit "import") <+> pp_mod <> parens empty ]
+                 nest 2 (ptext (sLit "except perhaps to import instances from")
+                                   <+> quotes pp_mod),
+                 ptext (sLit "To import instances alone, use:")
+                                   <+> ptext (sLit "import") <+> pp_mod <> parens empty ]
     msg2 = sep [pp_herald <+> quotes (pprWithCommas ppr unused),
-                   text "from module" <+> quotes pp_mod <+> pp_not_used]
+                    text "from module" <+> quotes pp_mod <+> pp_not_used]
     pp_herald   = text "The import of"
     pp_mod      = ppr (unLoc (ideclName decl))
     pp_not_used = text "is redundant"
@@ -1386,6 +1386,11 @@ printMinimalImports imports_w_usage
 %************************************************************************
 
 \begin{code}
+qualImportItemErr :: RdrName -> SDoc
+qualImportItemErr rdr
+  = hang (ptext (sLit "Illegal qualified name in import item:"))
+       2 (ppr rdr)
+
 badImportItemErr :: ModIface -> ImpDeclSpec -> IE RdrName -> SDoc
 badImportItemErr iface decl_spec ie
   = sep [ptext (sLit "Module"), quotes (ppr (is_mod decl_spec)), source_import,