improve the cyclic module error message as per #1856

[ghc-hetmet.git] / compiler / main / GHC.hs

diff --git a/compiler/main/GHC.hs b/compiler/main/GHC.hs
index b00f79f..0be0fc4 100644 (file)
--- a/compiler/main/GHC.hs
+++ b/compiler/main/GHC.hs
@@ -58,9 +58,6 @@ module GHC (
         compileCoreToObj,
         getModSummary,
 
-       -- * Parsing Haddock comments
-       parseHaddockComment,
-
        -- * Inspecting the module structure of the program
        ModuleGraph, ModSummary(..), ms_mod_name, ModLocation(..),
        getModuleGraph,
@@ -300,8 +297,6 @@ import StringBuffer ( StringBuffer, hGetStringBuffer, nextChar )
 import Outputable
 import BasicTypes
 import Maybes          ( expectJust, mapCatMaybes )
-import HaddockParse
-import HaddockLex       ( tokenise )
 import FastString
 import Lexer
 
@@ -626,15 +621,6 @@ setGlobalTypeScope ids
       hscEnv{ hsc_global_type_env = extendTypeEnvWithIds emptyTypeEnv ids }
 
 -- -----------------------------------------------------------------------------
--- Parsing Haddock comments
-
-parseHaddockComment :: String -> Either String (HsDoc RdrName)
-parseHaddockComment string = 
-  case parseHaddockParagraphs (tokenise string) of
-    MyLeft x  -> Left x
-    MyRight x -> Right x
-
--- -----------------------------------------------------------------------------
 -- Loading the program
 
 -- | Perform a dependency analysis starting from the current targets
@@ -1035,7 +1021,7 @@ instance DesugaredMod DesugaredModule where
 
 type ParsedSource      = Located (HsModule RdrName)
 type RenamedSource     = (HsGroup Name, [LImportDecl Name], Maybe [LIE Name],
-                          Maybe (HsDoc Name), HaddockModInfo Name)
+                          Maybe LHsDocString)
 type TypecheckedSource = LHsBinds Id
 
 -- NOTE:
@@ -2332,18 +2318,28 @@ cyclicModuleErr ms
   = hang (ptext (sLit "Module imports form a cycle for modules:"))
        2 (vcat (map show_one ms))
   where
-    show_one ms = sep [ show_mod (ms_hsc_src ms) (ms_mod ms),
-                       nest 2 $ ptext (sLit "imports:") <+> 
-                                  (pp_imps HsBootFile (ms_srcimps ms)
-                                  $$ pp_imps HsSrcFile  (ms_imps ms))]
+    mods_in_cycle = map ms_mod_name ms
+    imp_modname = unLoc . ideclName . unLoc
+    just_in_cycle = filter ((`elem` mods_in_cycle) . imp_modname)
+
+    show_one ms = 
+           vcat [ show_mod (ms_hsc_src ms) (ms_mod_name ms) <+>
+                  maybe empty (parens . text) (ml_hs_file (ms_location ms)),
+                  nest 2 $ ptext (sLit "imports:") <+> vcat [
+                     pp_imps HsBootFile (just_in_cycle $ ms_srcimps ms),
+                     pp_imps HsSrcFile  (just_in_cycle $ ms_imps ms) ]
+                ]
     show_mod hsc_src mod = ppr mod <> text (hscSourceString hsc_src)
-    pp_imps src mods = fsep (map (show_mod src) mods)
+    pp_imps src imps = fsep (map (show_mod src . unLoc . ideclName . unLoc) imps)
 
 
 -- | Inform GHC that the working directory has changed.  GHC will flush
 -- its cache of module locations, since it may no longer be valid.
--- Note: if you change the working directory, you should also unload
--- the current program (set targets to empty, followed by load).
+-- 
+-- Note: Before changing the working directory make sure all threads running
+-- in the same session have stopped.  If you change the working directory,
+-- you should also unload the current program (set targets to empty,
+-- followed by load).
 workingDirectoryChanged :: GhcMonad m => m ()
 workingDirectoryChanged = withSession $ (liftIO . flushFinderCaches)
 
@@ -2533,7 +2529,7 @@ packageDbModules only_exposed = do
    return $
      [ mkModule pid modname | p <- pkgs
                             , not only_exposed || exposed p
-                            , pid <- [mkPackageId (package p)]
+                            , let pid = packageConfigId p
                             , modname <- exposedModules p ]
 
 -- -----------------------------------------------------------------------------