Interface file optimisation and removal of nameParent

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

diff --git a/compiler/rename/RnEnv.lhs b/compiler/rename/RnEnv.lhs
index 29a8791..74c9646 100644 (file)
--- a/compiler/rename/RnEnv.lhs
+++ b/compiler/rename/RnEnv.lhs
@@ -1,5 +1,5 @@
 %
-% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-2006
 %
 \section[RnEnv]{Environment manipulation for the renamer monad}
 
@@ -47,11 +47,13 @@ import RdrName              ( RdrName, isQual, isUnqual, isOrig_maybe,
                          Provenance(..), pprNameProvenance,
                          importSpecLoc, importSpecModule
                        )
-import HscTypes                ( availNames, ModIface(..), FixItem(..), lookupFixity )
+import HscTypes                ( availNames, ModIface(..), FixItem(..), lookupFixity,
+                          AvailInfo, GenAvailInfo(..) )
 import TcRnMonad
 import Name            ( Name, nameIsLocalOrFrom, mkInternalName, isWiredInName,
-                         nameSrcLoc, nameOccName, nameModule, nameParent, isExternalName )
+                         nameSrcLoc, nameOccName, nameModule, isExternalName )
 import NameSet
+import NameEnv          ( NameEnv, lookupNameEnv )
 import OccName         ( tcName, isDataOcc, pprNonVarNameSpace, occNameSpace,
                          reportIfUnused )
 import Module          ( Module, ModuleName )
@@ -75,8 +77,8 @@ import DynFlags
 %*********************************************************
 
 \begin{code}
-newTopSrcBinder :: Module -> Maybe Name -> Located RdrName -> RnM Name
-newTopSrcBinder this_mod mb_parent (L loc rdr_name)
+newTopSrcBinder :: Module -> Located RdrName -> RnM Name
+newTopSrcBinder this_mod (L loc rdr_name)
   | Just name <- isExact_maybe rdr_name
   =    -- This is here to catch 
        --   (a) Exact-name binders created by Template Haskell
@@ -113,7 +115,7 @@ newTopSrcBinder this_mod mb_parent (L loc rdr_name)
        -- the RdrName, not from the environment.  In principle, it'd be fine to 
        -- have an arbitrary mixture of external core definitions in a single module,
        -- (apart from module-initialisation issues, perhaps).
-       ; newGlobalBinder rdr_mod rdr_occ mb_parent (srcSpanStart loc) }
+       ; newGlobalBinder rdr_mod rdr_occ (srcSpanStart loc) }
                --TODO, should pass the whole span
 
   | otherwise
@@ -121,7 +123,7 @@ newTopSrcBinder this_mod mb_parent (L loc rdr_name)
                 (addErrAt loc (badQualBndrErr rdr_name))
                -- Binders should not be qualified; if they are, and with a different
                -- module name, we we get a confusing "M.T is not in scope" error later
-       ; newGlobalBinder this_mod (rdrNameOcc rdr_name) mb_parent (srcSpanStart loc) }
+       ; newGlobalBinder this_mod (rdrNameOcc rdr_name) (srcSpanStart loc) }
 \end{code}
 
 %*********************************************************
@@ -173,7 +175,7 @@ lookupTopBndrRn rdr_name
        -- we don't bother to call newTopSrcBinder first
        -- We assume there is no "parent" name
   = do { loc <- getSrcSpanM
-       ; newGlobalBinder rdr_mod rdr_occ Nothing (srcSpanStart loc) }
+       ; newGlobalBinder rdr_mod rdr_occ (srcSpanStart loc) }
 
   | otherwise
   = do { mb_gre <- lookupGreLocalRn rdr_name
@@ -199,10 +201,18 @@ lookupLocatedSigOccRn = lookupLocatedBndrRn
 -- disambiguate.  
 
 lookupLocatedInstDeclBndr :: Name -> Located RdrName -> RnM (Located Name)
-lookupLocatedInstDeclBndr cls = wrapLocM (lookupInstDeclBndr cls)
-
-lookupInstDeclBndr :: Name -> RdrName -> RnM Name
-lookupInstDeclBndr cls_name rdr_name
+lookupLocatedInstDeclBndr cls rdr = do
+   imp_avails <- getImports
+   wrapLocM (lookupInstDeclBndr (imp_parent imp_avails) cls) rdr
+
+lookupInstDeclBndr :: NameEnv AvailInfo -> Name -> RdrName -> RnM Name
+-- This is called on the method name on the left-hand side of an 
+-- instance declaration binding. eg.  instance Functor T where
+--                                       fmap = ...
+--                                       ^^^^ called on this
+-- Regardless of how many unqualified fmaps are in scope, we want
+-- the one that comes from the Functor class.
+lookupInstDeclBndr availenv cls_name rdr_name
   | isUnqual rdr_name  -- Find all the things the rdr-name maps to
   = do {               -- and pick the one with the right parent name
          let { is_op gre     = cls_name == nameParent (gre_name gre)
@@ -220,6 +230,12 @@ lookupInstDeclBndr cls_name rdr_name
          -- NB: qualified names are rejected by the parser
     lookupImportedName rdr_name
 
+  where nameParent nm
+           | Just (AvailTC tc subs) <- lookupNameEnv availenv nm = tc
+           | otherwise = nm -- might be an Avail, if the Name is 
+                            -- in scope some other way
+                                   
+
 newIPNameRn :: IPName RdrName -> TcRnIf m n (IPName Name)
 newIPNameRn ip_rdr = newIPName (mapIPName rdrNameOcc ip_rdr)
 
@@ -243,7 +259,7 @@ lookupFamInstDeclBndr mod lrdr_name@(L _ rdr_name)
    lookupGreRn rdr_name                        `thenM` \ mb_gre ->
    case mb_gre of {
        Just gre -> returnM (gre_name gre) ;
-       Nothing  -> newTopSrcBinder mod Nothing lrdr_name }
+       Nothing  -> newTopSrcBinder mod lrdr_name }
 
 --------------------------------------------------
 --             Occurrences