[project @ 2000-11-21 13:13:25 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 f7e34dd..e4621a0 100644 (file)
--- a/ghc/compiler/rename/RnEnv.lhs
+++ b/ghc/compiler/rename/RnEnv.lhs
@@ -11,7 +11,7 @@ module RnEnv where            -- Export everything
 import HsSyn
 import RdrHsSyn                ( RdrNameIE )
 import RdrName         ( RdrName, rdrNameModule, rdrNameOcc, isQual, isUnqual, isOrig,
-                         mkRdrUnqual, mkRdrUnqual, qualifyRdrName, lookupRdrEnv, foldRdrEnv
+                         mkRdrUnqual, mkRdrQual, qualifyRdrName, lookupRdrEnv, foldRdrEnv
                        )
 import HsTypes         ( hsTyVarName, replaceTyVarName )
 import HscTypes                ( Provenance(..), pprNameProvenance, hasBetterProv,
@@ -486,6 +486,56 @@ 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
+              -> [AvailInfo]           -- What's to be hidden (but only the unqualified 
+                                       --      version is hidden)
+              -> (Name -> Provenance)
+              -> Avails                -- Whats imported and how
+              -> GlobalRdrEnv
+
+mkGlobalRdrEnv this_mod unqual_imp hides mk_provenance avails
+  = gbl_env2
+  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
+    gbl_env1 = foldl add_avail emptyRdrEnv avails
+
+       -- Delete things that are hidden
+    gbl_env2 = foldl del_avail gbl_env1 hides
+
+    add_avail :: GlobalRdrEnv -> AvailInfo -> GlobalRdrEnv
+    add_avail env avail = foldl add_name env (availNames avail)
+
+    add_name env name
+       | unqual_imp = env2
+       | otherwise  = env1
+       where
+         env1 = addOneToGlobalRdrEnv env  (mkRdrQual this_mod occ) (name,prov)
+         env2 = addOneToGlobalRdrEnv env1 (mkRdrUnqual occ)        (name,prov)
+         occ  = nameOccName name
+         prov = mk_provenance 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
+-- environment because we don't have enough info, but we compromise
+-- by making an environment from its exports
+mkIfaceGlobalRdrEnv m_avails
+  = foldl add emptyRdrEnv m_avails
+  where
+    add env (mod,avails) = plusGlobalRdrEnv env (mkGlobalRdrEnv mod True [] (\n -> LocalDef) avails)
+\end{code}
+
+\begin{code}
 plusGlobalRdrEnv :: GlobalRdrEnv -> GlobalRdrEnv -> GlobalRdrEnv
 plusGlobalRdrEnv env1 env2 = plusFM_C combine_globals env1 env2