%
-% (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}
lookupLocatedGlobalOccRn, lookupGlobalOccRn,
lookupLocalDataTcNames, lookupSrcOcc_maybe,
lookupFixityRn, lookupTyFixityRn, lookupLocatedSigOccRn,
- lookupLocatedInstDeclBndr,
+ lookupInstDeclBndr, lookupRecordBndr, lookupConstructorFields,
lookupSyntaxName, lookupSyntaxTable, lookupImportedName,
+ lookupGreRn, lookupGreRn_maybe,
+ getLookupOccRn,
newLocalsRn, newIPNameRn,
bindLocalNames, bindLocalNamesFV,
mkRdrUnqual, setRdrNameSpace, rdrNameOcc,
pprGlobalRdrEnv, lookupGRE_RdrName,
isExact_maybe, isSrcRdrName,
+ Parent(..),
GlobalRdrElt(..), GlobalRdrEnv, lookupGlobalRdrEnv,
isLocalGRE, extendLocalRdrEnv, elemLocalRdrEnv, lookupLocalRdrEnv,
Provenance(..), pprNameProvenance,
importSpecLoc, importSpecModule
)
import HscTypes ( availNames, ModIface(..), FixItem(..), lookupFixity )
+import TcEnv ( tcLookupDataCon )
import TcRnMonad
import Name ( Name, nameIsLocalOrFrom, mkInternalName, isWiredInName,
- nameSrcLoc, nameOccName, nameModule, nameParent, isExternalName )
+ nameSrcLoc, nameOccName, nameModule, isExternalName )
import NameSet
+import NameEnv
+import DataCon ( dataConFieldLabels )
import OccName ( tcName, isDataOcc, pprNonVarNameSpace, occNameSpace,
reportIfUnused )
import Module ( Module, ModuleName )
srcLocSpan, getLoc, combineSrcSpans, isOneLineSpan )
import Outputable
import Util ( sortLe )
+import Maybes
import ListSetOps ( removeDups )
import List ( nubBy )
import Monad ( when )
%*********************************************************
\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
-- 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 loc }
--TODO, should pass the whole span
| otherwise
(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) loc }
\end{code}
%*********************************************************
-- 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 loc }
| otherwise
= do { mb_gre <- lookupGreLocalRn rdr_name
; case mb_gre of
- Nothing -> unboundName rdr_name
+ Nothing -> do
+ traceRn $ text "lookupTopBndrRn"
+ unboundName rdr_name
Just gre -> returnM (gre_name gre) }
-- lookupLocatedSigOccRn is used for type signatures and pragmas
-- The Haskell98 report does not stipulate this, but it will!
-- So we must treat the 'f' in the signature in the same way
-- as the binding occurrence of 'f', using lookupBndrRn
+--
+-- However, consider this case:
+-- import M( f )
+-- f :: Int -> Int
+-- g x = x
+-- We don't want to say 'f' is out of scope; instead, we want to
+-- return the imported 'f', so that later on the reanamer will
+-- correctly report "misplaced type sig".
lookupLocatedSigOccRn :: Located RdrName -> RnM (Located Name)
-lookupLocatedSigOccRn = lookupLocatedBndrRn
-
--- lookupInstDeclBndr is used for the binders in an
--- instance declaration. Here we use the class name to
--- disambiguate.
+lookupLocatedSigOccRn = wrapLocM $ \ rdr_name -> do
+ { local_env <- getLocalRdrEnv
+ ; case lookupLocalRdrEnv local_env rdr_name of {
+ Just n -> return n ;
+ Nothing -> do
+ { mb_gre <- lookupGreLocalRn rdr_name
+ ; case mb_gre of
+ Just gre -> return (gre_name gre)
+ Nothing -> lookupGlobalOccRn rdr_name
+ }}}
+
+-----------------------------------------------
+lookupInstDeclBndr :: Name -> Located RdrName -> RnM (Located 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.
+--
+-- Furthermore, note that we take no account of whether the
+-- name is only in scope qualified. I.e. even if method op is
+-- in scope as M.op, we still allow plain 'op' on the LHS of
+-- an instance decl
+lookupInstDeclBndr cls rdr = lookup_located_sub_bndr is_op
+ (ptext SLIT("method of class")) rdr
+ where
+ doc = ptext SLIT("method of class") <+> quotes (ppr cls)
+ is_op gre@(GRE {gre_par = ParentIs n}) = n == cls
+ is_op other = False
+
+-----------------------------------------------
+lookupRecordBndr :: Maybe (Located Name) -> Located RdrName -> RnM (Located Name)
+-- Used for record construction and pattern matching
+-- When the -fdisambiguate-record-fields flag is on, take account of the
+-- constructor name to disambiguate which field to use; it's just the
+-- same as for instance decls
+lookupRecordBndr Nothing rdr_name
+ = lookupLocatedGlobalOccRn rdr_name
+lookupRecordBndr (Just (L _ data_con)) rdr_name
+ = do { flag_on <- doptM Opt_DisambiguateRecordFields
+ ; if not flag_on
+ then lookupLocatedGlobalOccRn rdr_name
+ else do {
+ fields <- lookupConstructorFields data_con
+ ; let is_field gre = gre_name gre `elem` fields
+ ; lookup_located_sub_bndr is_field doc rdr_name
+ }}
+ where
+ doc = ptext SLIT("field of constructor") <+> quotes (ppr data_con)
+
+
+lookupConstructorFields :: Name -> RnM [Name]
+-- Look up the fields of a given constructor
+-- * For constructors from this module, use the record field env,
+-- which is itself gathered from the (as yet un-typechecked)
+-- data type decls
+--
+-- * For constructors from imported modules, use the *type* environment
+-- since imported modles are already compiled, the info is conveniently
+-- right there
+
+lookupConstructorFields con_name
+ = do { this_mod <- getModule
+ ; if nameIsLocalOrFrom this_mod con_name then
+ do { field_env <- getRecFieldEnv
+ ; return (lookupNameEnv field_env con_name `orElse` []) }
+ else
+ do { con <- tcLookupDataCon con_name
+ ; return (dataConFieldLabels con) } }
-lookupLocatedInstDeclBndr :: Name -> Located RdrName -> RnM (Located Name)
-lookupLocatedInstDeclBndr cls = wrapLocM (lookupInstDeclBndr cls)
+-----------------------------------------------
+lookup_located_sub_bndr :: (GlobalRdrElt -> Bool)
+ -> SDoc -> Located RdrName
+ -> RnM (Located Name)
+lookup_located_sub_bndr is_good doc rdr_name
+ = wrapLocM (lookup_sub_bndr is_good doc) rdr_name
-lookupInstDeclBndr :: Name -> RdrName -> RnM Name
-lookupInstDeclBndr cls_name rdr_name
+lookup_sub_bndr is_good doc 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)
- ; occ = rdrNameOcc rdr_name
- ; lookup_fn env = filter is_op (lookupGlobalRdrEnv env occ) }
- ; mb_gre <- lookupGreRn_help rdr_name lookup_fn
- ; case mb_gre of
- Just gre -> return (gre_name gre)
- Nothing -> do { addErr (unknownInstBndrErr cls_name rdr_name)
- ; return (mkUnboundName rdr_name) } }
+ ; env <- getGlobalRdrEnv
+ ; case filter is_good (lookupGlobalRdrEnv env (rdrNameOcc rdr_name)) of
+ -- NB: lookupGlobalRdrEnv, not lookupGRE_RdrName!
+ -- The latter does pickGREs, but we want to allow 'x'
+ -- even if only 'M.x' is in scope
+ [gre] -> return (gre_name gre)
+ [] -> do { addErr (unknownSubordinateErr doc rdr_name)
+ ; traceRn (text "RnEnv.lookup_sub_bndr" <+> ppr rdr_name)
+ ; return (mkUnboundName rdr_name) }
+ gres -> do { addNameClashErrRn rdr_name gres
+ ; return (gre_name (head gres)) }
+ }
| otherwise -- Occurs in derived instances, where we just
-- refer directly to the right method
--
lookupFamInstDeclBndr :: Module -> Located RdrName -> RnM Name
lookupFamInstDeclBndr mod lrdr_name@(L _ rdr_name)
- | not (isSrcRdrName rdr_name)
- = lookupImportedName rdr_name
-
- | otherwise
- = -- First look up the name in the normal environment.
- lookupGreRn rdr_name `thenM` \ mb_gre ->
- case mb_gre of {
- Just gre -> returnM (gre_name gre) ;
- Nothing -> newTopSrcBinder mod Nothing lrdr_name }
+ = do { mb_gre <- lookupGreRn_maybe rdr_name
+ ; case mb_gre of
+ Just gre -> returnM (gre_name gre) ;
+ Nothing -> newTopSrcBinder mod lrdr_name }
--------------------------------------------------
-- Occurrences
--------------------------------------------------
+getLookupOccRn :: RnM (Name -> Maybe Name)
+getLookupOccRn
+ = getLocalRdrEnv `thenM` \ local_env ->
+ return (lookupLocalRdrEnv local_env . mkRdrUnqual . nameOccName)
+
lookupLocatedOccRn :: Located RdrName -> RnM (Located Name)
lookupLocatedOccRn = wrapLocM lookupOccRn
| otherwise
= -- First look up the name in the normal environment.
- lookupGreRn rdr_name `thenM` \ mb_gre ->
+ lookupGreRn_maybe rdr_name `thenM` \ mb_gre ->
case mb_gre of {
Just gre -> returnM (gre_name gre) ;
Nothing ->
if isQual rdr_name && mod == iNTERACTIVE then
-- This test is not expensive,
lookupQualifiedName rdr_name -- and only happens for failed lookups
- else
+ else do
+ traceRn $ text "lookupGlobalOccRn"
unboundName rdr_name }
lookupImportedName :: RdrName -> TcRnIf m n Name
lookupSrcOcc_maybe :: RdrName -> RnM (Maybe Name)
-- No filter function; does not report an error on failure
lookupSrcOcc_maybe rdr_name
- = do { mb_gre <- lookupGreRn rdr_name
+ = do { mb_gre <- lookupGreRn_maybe rdr_name
; case mb_gre of
Nothing -> returnM Nothing
Just gre -> returnM (Just (gre_name gre)) }
-------------------------
-lookupGreRn :: RdrName -> RnM (Maybe GlobalRdrElt)
+lookupGreRn_maybe :: RdrName -> RnM (Maybe GlobalRdrElt)
-- Just look up the RdrName in the GlobalRdrEnv
-lookupGreRn rdr_name
+lookupGreRn_maybe rdr_name
= lookupGreRn_help rdr_name (lookupGRE_RdrName rdr_name)
+lookupGreRn :: RdrName -> RnM GlobalRdrElt
+-- If not found, add error message, and return a fake GRE
+lookupGreRn rdr_name
+ = do { mb_gre <- lookupGreRn_maybe rdr_name
+ ; case mb_gre of {
+ Just gre -> return gre ;
+ Nothing -> do
+ { traceRn $ text "lookupGreRn"
+ ; name <- unboundName rdr_name
+ ; return (GRE { gre_name = name, gre_par = NoParent,
+ gre_prov = LocalDef }) }}}
+
lookupGreLocalRn :: RdrName -> RnM (Maybe GlobalRdrElt)
-- Similar, but restricted to locally-defined things
lookupGreLocalRn rdr_name
* "do" notation
We store the relevant Name in the HsSyn tree, in
- * HsIntegral/HsFractional
+ * HsIntegral/HsFractional/HsIsString
* NegApp
* NPlusKPat
* HsDo
| otherwise = ASSERT2( isUnqual rdr_name, ppr rdr_name )
-- We only bind unqualified names here
-- lookupRdrEnv doesn't even attempt to look up a qualified RdrName
- mkInternalName uniq (rdrNameOcc rdr_name) (srcSpanStart loc)
+ mkInternalName uniq (rdrNameOcc rdr_name) loc
bindLocatedLocalsRn :: SDoc -- Documentation string for error message
-> [Located RdrName]
-------------------------
-- Helpers
warnUnusedGREs gres
- = warnUnusedBinds [(n,Just p) | GRE {gre_name = n, gre_prov = p} <- gres]
+ = warnUnusedBinds [(n,p) | GRE {gre_name = n, gre_prov = p} <- gres]
warnUnusedLocals names
- = warnUnusedBinds [(n,Nothing) | n<-names]
+ = warnUnusedBinds [(n,LocalDef) | n<-names]
-warnUnusedBinds :: [(Name,Maybe Provenance)] -> RnM ()
+warnUnusedBinds :: [(Name,Provenance)] -> RnM ()
warnUnusedBinds names = mappM_ warnUnusedName (filter reportable names)
where reportable (name,_)
| isWiredInName name = False -- Don't report unused wired-in names
-------------------------
-warnUnusedName :: (Name, Maybe Provenance) -> RnM ()
-warnUnusedName (name, prov)
- = addWarnAt loc $
+warnUnusedName :: (Name, Provenance) -> RnM ()
+warnUnusedName (name, LocalDef)
+ = addUnusedWarning name (srcLocSpan (nameSrcLoc name))
+ (ptext SLIT("Defined but not used"))
+
+warnUnusedName (name, Imported is)
+ = mapM_ warn is
+ where
+ warn spec = addUnusedWarning name span msg
+ where
+ span = importSpecLoc spec
+ pp_mod = quotes (ppr (importSpecModule spec))
+ msg = ptext SLIT("Imported from") <+> pp_mod <+> ptext SLIT("but not used")
+
+addUnusedWarning name span msg
+ = addWarnAt span $
sep [msg <> colon,
nest 2 $ pprNonVarNameSpace (occNameSpace (nameOccName name))
<+> quotes (ppr name)]
- -- TODO should be a proper span
- where
- (loc,msg) = case prov of
- Just (Imported is)
- -> (importSpecLoc imp_spec, imp_from (importSpecModule imp_spec))
- where
- imp_spec = head is
- other -> (srcLocSpan (nameSrcLoc name), unused_msg)
-
- unused_msg = text "Defined but not used"
- imp_from mod = text "Imported from" <+> quotes (ppr mod) <+> text "but not used"
\end{code}
\begin{code}
nest 2 $ pprNonVarNameSpace (occNameSpace (rdrNameOcc rdr_name))
<+> quotes (ppr rdr_name)]
-unknownInstBndrErr cls op
- = quotes (ppr op) <+> ptext SLIT("is not a (visible) method of class") <+> quotes (ppr cls)
+unknownSubordinateErr doc op -- Doc is "method of class" or
+ -- "field of constructor"
+ = quotes (ppr op) <+> ptext SLIT("is not a (visible)") <+> doc
badOrigBinding name
= ptext SLIT("Illegal binding of built-in syntax:") <+> ppr (rdrNameOcc name)
projects / ghc-hetmet.git / blobdiff