[project @ 2001-07-12 14:51:28 by simonpj]

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

diff --git a/ghc/compiler/rename/RnEnv.lhs b/ghc/compiler/rename/RnEnv.lhs
index d7167ad..a83890d 100644 (file)
--- a/ghc/compiler/rename/RnEnv.lhs
+++ b/ghc/compiler/rename/RnEnv.lhs
@@ -13,7 +13,8 @@ import {-# SOURCE #-} RnHiFiles
 import HsSyn
 import RdrHsSyn                ( RdrNameIE )
 import RdrName         ( RdrName, rdrNameModule, rdrNameOcc, isQual, isUnqual, isOrig,
-                         mkRdrUnqual, mkRdrQual, lookupRdrEnv, foldRdrEnv
+                         mkRdrUnqual, mkRdrQual, lookupRdrEnv, foldRdrEnv, rdrEnvToList,
+                         unqualifyRdrName
                        )
 import HsTypes         ( hsTyVarName, replaceTyVarName )
 import HscTypes                ( Provenance(..), pprNameProvenance, hasBetterProv,
@@ -640,48 +641,58 @@ checkDupNames doc_str rdr_names_w_loc
 \begin{code}
 mkGlobalRdrEnv :: ModuleName           -- Imported module (after doing the "as M" name change)
               -> Bool                  -- True <=> want unqualified import
-              -> Bool                  -- True <=> want qualified import
-              -> [AvailInfo]           -- What's to be hidden (but only the unqualified 
-                                       --      version is hidden)
               -> (Name -> Provenance)
-              -> Avails                -- Whats imported and how
+              -> Avails                -- Whats imported
+              -> Avails                -- What's to be hidden
+                                       -- I.e. import (imports - hides)
               -> Deprecations
               -> GlobalRdrEnv
 
-mkGlobalRdrEnv this_mod unqual_imp qual_imp hides 
-              mk_provenance avails deprecs
-  = gbl_env2
+mkGlobalRdrEnv this_mod unqual_imp mk_provenance avails hides deprecs
+  = gbl_env3
   where
        -- Make the name environment.  We're talking about a 
        -- single module here, so there must be no name clashes.
        -- In practice there only ever will be if it's the module
        -- being compiled.
 
-       -- Add the things that are available
+       -- Add qualified names for the things that are available
+       -- (Qualified names are always imported)
     gbl_env1 = foldl add_avail emptyRdrEnv avails
 
-       -- Delete things that are hidden
+       -- Delete (qualified names of) things that are hidden
     gbl_env2 = foldl del_avail gbl_env1 hides
 
+       -- Add unqualified names
+    gbl_env3 | unqual_imp = foldl add_unqual gbl_env2 (rdrEnvToList gbl_env2)
+            | otherwise  = gbl_env2
+
+    add_unqual env (qual_name, elts)
+       = foldl add_one env elts
+       where
+         add_one env elt = addOneToGlobalRdrEnv env unqual_name elt
+         unqual_name     = unqualifyRdrName qual_name
+       -- The qualified import should only have added one 
+       -- binding for each qualified name!  But if there's an error in
+       -- the module (multiple bindings for the same name) we may get
+       -- duplicates.  So the simple thing is to do the fold.
+
+    del_avail env avail 
+       = foldl delOneFromGlobalRdrEnv env rdr_names
+       where
+         rdr_names = map (mkRdrQual this_mod . nameOccName)
+                         (availNames avail)
+
+
     add_avail :: GlobalRdrEnv -> AvailInfo -> GlobalRdrEnv
     add_avail env avail = foldl add_name env (availNames avail)
 
-    add_name env name
-       | qual_imp && unqual_imp = env3
-       | unqual_imp             = env2
-       | qual_imp               = env1
-       | otherwise              = env
+    add_name env name  -- Add qualified name only
+       = addOneToGlobalRdrEnv env  (mkRdrQual this_mod occ) elt
        where
-         env1 = addOneToGlobalRdrEnv env  (mkRdrQual this_mod occ) elt
-         env2 = addOneToGlobalRdrEnv env  (mkRdrUnqual occ)        elt
-         env3 = addOneToGlobalRdrEnv env1 (mkRdrUnqual occ)        elt
          occ  = nameOccName name
          elt  = GRE name (mk_provenance name) (lookupDeprec deprecs name)
 
-    del_avail env avail = foldl delOneFromGlobalRdrEnv env rdr_names
-                       where
-                         rdr_names = map (mkRdrUnqual . nameOccName) (availNames avail)
-
 mkIfaceGlobalRdrEnv :: [(ModuleName,Avails)] -> GlobalRdrEnv
 -- Used to construct a GlobalRdrEnv for an interface that we've
 -- read from a .hi file.  We can't construct the original top-level
@@ -690,8 +701,8 @@ mkIfaceGlobalRdrEnv :: [(ModuleName,Avails)] -> GlobalRdrEnv
 mkIfaceGlobalRdrEnv m_avails
   = foldl add emptyRdrEnv m_avails
   where
-    add env (mod,avails) = plusGlobalRdrEnv env (mkGlobalRdrEnv mod True False [] 
-                                                               (\n -> LocalDef) avails NoDeprecs)
+    add env (mod,avails) = plusGlobalRdrEnv env (mkGlobalRdrEnv mod True 
+                                                               (\n -> LocalDef) avails [] NoDeprecs)
                -- The NoDeprecs is a bit of a hack I suppose
 \end{code}