X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Frename%2FRnEnv.lhs;h=2ecaf612954c63302e2c74cf2c979ab4a69ce752;hp=801dda860c0105a6b243a044689f576b5293c48a;hb=7bb3d1fc79521d591cd9f824893963141a7997b6;hpb=6c7b41cc2b24f533697a62bf1843507ae043fc97 diff --git a/compiler/rename/RnEnv.lhs b/compiler/rename/RnEnv.lhs index 801dda8..2ecaf61 100644 --- a/compiler/rename/RnEnv.lhs +++ b/compiler/rename/RnEnv.lhs @@ -1,70 +1,65 @@ -\% +% % (c) The GRASP/AQUA Project, Glasgow University, 1992-2006 % \section[RnEnv]{Environment manipulation for the renamer monad} \begin{code} -{-# OPTIONS -w #-} --- The above warning supression flag is a temporary kludge. --- While working on this module you are encouraged to remove it and fix --- any warnings in the module. See --- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings --- for details - module RnEnv ( newTopSrcBinder, lookupFamInstDeclBndr, - lookupLocatedBndrRn, lookupBndrRn, lookupBndrRn_maybe, - lookupLocatedTopBndrRn, lookupTopBndrRn, lookupBndrRn_maybe, + lookupLocatedTopBndrRn, lookupTopBndrRn, lookupLocatedOccRn, lookupOccRn, - lookupLocatedGlobalOccRn, lookupGlobalOccRn, - lookupLocalDataTcNames, lookupSrcOcc_maybe, - lookupFixityRn, lookupTyFixityRn, lookupLocatedSigOccRn, + lookupLocatedGlobalOccRn, + lookupGlobalOccRn, lookupGlobalOccRn_maybe, + lookupLocalDataTcNames, lookupSigOccRn, + lookupFixityRn, lookupTyFixityRn, lookupInstDeclBndr, lookupRecordBndr, lookupConstructorFields, - lookupSyntaxName, lookupSyntaxTable, lookupImportedName, + lookupSyntaxName, lookupSyntaxTable, lookupGreRn, lookupGreLocalRn, lookupGreRn_maybe, - getLookupOccRn, + getLookupOccRn, addUsedRdrNames, newLocalsRn, newIPNameRn, - bindLocalNames, bindLocalNamesFV, bindLocalNamesFV_WithFixities, + bindLocalNames, bindLocalNamesFV, + MiniFixityEnv, emptyFsEnv, extendFsEnv, lookupFsEnv, + bindLocalNamesFV_WithFixities, bindLocatedLocalsFV, bindLocatedLocalsRn, bindSigTyVarsFV, bindPatSigTyVars, bindPatSigTyVarsFV, bindTyVarsRn, extendTyVarEnvFVRn, - bindLocalFixities, checkDupRdrNames, checkDupNames, checkShadowedNames, checkDupAndShadowedRdrNames, mapFvRn, mapFvRnCPS, warnUnusedMatches, warnUnusedModules, warnUnusedImports, warnUnusedTopBinds, warnUnusedLocalBinds, - dataTcOccs, unknownNameErr, + dataTcOccs, unknownNameErr, kindSigErr, perhapsForallMsg, + + checkM ) where #include "HsVersions.h" import LoadIface ( loadInterfaceForName, loadSrcInterface ) import IfaceEnv ( lookupOrig, newGlobalBinder, newIPName ) -import HsSyn ( FixitySig(..), HsExpr(..), SyntaxExpr, SyntaxTable, - LHsTyVarBndr, LHsType, - Fixity, hsLTyVarLocNames, replaceTyVarName ) +import HsSyn import RdrHsSyn ( extractHsTyRdrTyVars ) import RdrName import HscTypes ( availNames, ModIface(..), FixItem(..), lookupFixity) -import TcEnv ( tcLookupDataCon ) +import TcEnv ( tcLookupDataCon, tcLookupField, isBrackStage ) import TcRnMonad +import Id ( isRecordSelector ) import Name ( Name, nameIsLocalOrFrom, mkInternalName, isWiredInName, nameSrcLoc, nameSrcSpan, nameOccName, nameModule, isExternalName ) import NameSet import NameEnv -import UniqFM +import LazyUniqFM import DataCon ( dataConFieldLabels ) -import OccName ( OccName, tcName, isDataOcc, pprNonVarNameSpace, occNameSpace, - reportIfUnused, occNameFS ) +import OccName import Module ( Module, ModuleName ) -import PrelNames ( mkUnboundName, rOOT_MAIN, iNTERACTIVE, consDataConKey, hasKey ) +import PrelNames ( mkUnboundName, rOOT_MAIN, iNTERACTIVE, + consDataConKey, hasKey, forall_tv_RDR ) import UniqSupply import BasicTypes ( IPName, mapIPName, Fixity ) -import SrcLoc ( SrcSpan, srcSpanStart, Located(..), eqLocated, unLoc, - srcLocSpan, getLoc, combineSrcSpans, isOneLineSpan ) +import ErrUtils ( Message ) +import SrcLoc import Outputable import Util import Maybes @@ -73,6 +68,7 @@ import List ( nubBy ) import DynFlags import FastString import Control.Monad +import qualified Data.Set as Set \end{code} \begin{code} @@ -149,7 +145,16 @@ newTopSrcBinder this_mod (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) loc } + + ; stage <- getStage + ; if isBrackStage stage then + -- We are inside a TH bracket, so make an *Internal* name + -- See Note [Top-level Names in Template Haskell decl quotes] in RnNames + do { uniq <- newUnique + ; return (mkInternalName uniq (rdrNameOcc rdr_name) loc) } + else + -- Normal case + newGlobalBinder this_mod (rdrNameOcc rdr_name) loc } \end{code} %********************************************************* @@ -160,17 +165,19 @@ newTopSrcBinder this_mod (L loc rdr_name) Looking up a name in the RnEnv. -\begin{code} -lookupLocatedBndrRn :: Located RdrName -> RnM (Located Name) -lookupLocatedBndrRn = wrapLocM lookupBndrRn - -lookupBndrRn :: RdrName -> RnM Name -lookupBndrRn n = do nopt <- lookupBndrRn_maybe n - case nopt of - Just n' -> return n' - Nothing -> do traceRn $ text "lookupTopBndrRn" - unboundName n +Note [Type and class operator definitions] +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +We want to reject all of these unless we have -XTypeOperators (Trac #3265) + data a :*: b = ... + class a :*: b where ... + data (:*:) a b = .... + class (:*:) a b where ... +The latter two mean that we are not just looking for a +*syntactically-infix* declaration, but one that uses an operator +OccName. We use OccName.isSymOcc to detect that case, which isn't +terribly efficient, but there seems to be no better way. +\begin{code} lookupTopBndrRn :: RdrName -> RnM Name lookupTopBndrRn n = do nopt <- lookupTopBndrRn_maybe n case nopt of @@ -178,14 +185,6 @@ lookupTopBndrRn n = do nopt <- lookupTopBndrRn_maybe n Nothing -> do traceRn $ text "lookupTopBndrRn" unboundName n -lookupBndrRn_maybe :: RdrName -> RnM (Maybe Name) --- NOTE: assumes that the SrcSpan of the binder has already been setSrcSpan'd -lookupBndrRn_maybe rdr_name - = getLocalRdrEnv `thenM` \ local_env -> - case lookupLocalRdrEnv local_env rdr_name of - Just name -> returnM (Just name) - Nothing -> lookupTopBndrRn_maybe rdr_name - lookupLocatedTopBndrRn :: Located RdrName -> RnM (Located Name) lookupLocatedTopBndrRn = wrapLocM lookupTopBndrRn @@ -219,40 +218,18 @@ lookupTopBndrRn_maybe rdr_name ; return (Just n)} | otherwise - = do { mb_gre <- lookupGreLocalRn rdr_name + = do { -- Check for operators in type or class declarations + -- See Note [Type and class operator definitions] + let occ = rdrNameOcc rdr_name + ; when (isTcOcc occ && isSymOcc occ) + (do { op_ok <- doptM Opt_TypeOperators + ; checkM op_ok (addErr (opDeclErr rdr_name)) }) + + ; mb_gre <- lookupGreLocalRn rdr_name ; case mb_gre of Nothing -> returnM Nothing Just gre -> returnM (Just $ gre_name gre) } --- lookupLocatedSigOccRn is used for type signatures and pragmas --- Is this valid? --- module A --- import M( f ) --- f :: Int -> Int --- f x = x --- It's clear that the 'f' in the signature must refer to A.f --- 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 = 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) @@ -269,16 +246,23 @@ lookupInstDeclBndr :: Name -> Located RdrName -> RnM (Located Name) -- an instance decl lookupInstDeclBndr cls rdr = lookup_located_sub_bndr is_op doc 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 + doc = ptext (sLit "method of class") <+> quotes (ppr cls) + is_op (GRE {gre_par = ParentIs n}) = n == cls + is_op _ = 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 +-- When the -XDisambiguateRecordFields flag is on, take account of the -- constructor name to disambiguate which field to use; it's just the -- same as for instance decls +-- +-- NB: Consider this: +-- module Foo where { data R = R { fld :: Int } } +-- module Odd where { import Foo; fld x = x { fld = 3 } } +-- Arguably this should work, because the reference to 'fld' is +-- unambiguous because there is only one field id 'fld' in scope. +-- But currently it's rejected. lookupRecordBndr Nothing rdr_name = lookupLocatedGlobalOccRn rdr_name lookupRecordBndr (Just (L _ data_con)) rdr_name @@ -291,7 +275,7 @@ lookupRecordBndr (Just (L _ data_con)) rdr_name ; lookup_located_sub_bndr is_field doc rdr_name }} where - doc = ptext SLIT("field of constructor") <+> quotes (ppr data_con) + doc = ptext (sLit "field of constructor") <+> quotes (ppr data_con) lookupConstructorFields :: Name -> RnM [Name] @@ -307,7 +291,7 @@ lookupConstructorFields :: Name -> RnM [Name] lookupConstructorFields con_name = do { this_mod <- getModule ; if nameIsLocalOrFrom this_mod con_name then - do { field_env <- getRecFieldEnv + do { RecFields field_env _ <- getRecFieldEnv ; return (lookupNameEnv field_env con_name `orElse` []) } else do { con <- tcLookupDataCon con_name @@ -320,9 +304,11 @@ lookup_located_sub_bndr :: (GlobalRdrElt -> Bool) lookup_located_sub_bndr is_good doc rdr_name = wrapLocM (lookup_sub_bndr is_good doc) rdr_name +lookup_sub_bndr :: (GlobalRdrElt -> Bool) -> SDoc -> RdrName -> RnM 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 + ; addUsedRdrName rdr_name ; env <- getGlobalRdrEnv ; case filter is_good (lookupGlobalRdrEnv env (rdrNameOcc rdr_name)) of -- NB: lookupGlobalRdrEnv, not lookupGRE_RdrName! @@ -337,30 +323,25 @@ lookup_sub_bndr is_good doc rdr_name } | otherwise -- Occurs in derived instances, where we just - -- refer directly to the right method - = ASSERT2( not (isQual rdr_name), ppr rdr_name ) - -- NB: qualified names are rejected by the parser - lookupImportedName rdr_name + -- refer directly to the right method with an Orig + -- And record fields can be Quals: C { F.f = x } + = lookupGlobalOccRn rdr_name newIPNameRn :: IPName RdrName -> TcRnIf m n (IPName Name) newIPNameRn ip_rdr = newIPName (mapIPName rdrNameOcc ip_rdr) --- Looking up family names in type instances is a subtle affair. The family --- may be imported, in which case we need to lookup the occurence of a global --- name. Alternatively, the family may be in the same binding group (and in --- fact in a declaration processed later), and we need to create a new top --- source binder. --- --- So, also this is strictly speaking an occurence, we cannot raise an error --- message yet for instances without a family declaration. This will happen --- during renaming the type instance declaration in RnSource.rnTyClDecl. +-- If the family is declared locally, it will not yet be in the main +-- environment; hence, we pass in an extra one here, which we check first. +-- See "Note [Looking up family names in family instances]" in 'RnNames'. -- -lookupFamInstDeclBndr :: Module -> Located RdrName -> RnM Name -lookupFamInstDeclBndr mod lrdr_name@(L _ rdr_name) - = do { mb_gre <- lookupGreRn_maybe rdr_name - ; case mb_gre of - Just gre -> returnM (gre_name gre) ; - Nothing -> newTopSrcBinder mod lrdr_name } +lookupFamInstDeclBndr :: GlobalRdrEnv -> Located RdrName -> RnM Name +lookupFamInstDeclBndr tyclGroupEnv (L loc rdr_name) + = setSrcSpan loc $ + case lookupGRE_RdrName rdr_name tyclGroupEnv of + (gre:_) -> return $ gre_name gre + -- if there is more than one, an error will be raised elsewhere + [] -> lookupOccRn rdr_name + -------------------------------------------------- -- Occurrences @@ -387,58 +368,50 @@ lookupLocatedGlobalOccRn = wrapLocM lookupGlobalOccRn lookupGlobalOccRn :: RdrName -> RnM Name -- lookupGlobalOccRn is like lookupOccRn, except that it looks in the global --- environment. It's used only for --- record field names --- class op names in class and instance decls +-- environment. Adds an error message if the RdrName is not in scope. +-- Also has a special case for GHCi. lookupGlobalOccRn rdr_name - | not (isSrcRdrName rdr_name) - = lookupImportedName rdr_name + = do { -- First look up the name in the normal environment. + mb_name <- lookupGlobalOccRn_maybe rdr_name + ; case mb_name of { + Just n -> return n ; + Nothing -> do + + { -- We allow qualified names on the command line to refer to + -- *any* name exported by any module in scope, just as if there + -- was an "import qualified M" declaration for every module. + allow_qual <- doptM Opt_ImplicitImportQualified + ; mod <- getModule + -- This test is not expensive, + -- and only happens for failed lookups + ; if isQual rdr_name && allow_qual && mod == iNTERACTIVE + then lookupQualifiedName rdr_name + else unboundName rdr_name } } } + +lookupGlobalOccRn_maybe :: RdrName -> RnM (Maybe Name) +-- No filter function; does not report an error on failure + +lookupGlobalOccRn_maybe rdr_name + | Just n <- isExact_maybe rdr_name -- This happens in derived code + = return (Just n) - | otherwise - = -- First look up the name in the normal environment. - lookupGreRn_maybe rdr_name `thenM` \ mb_gre -> - case mb_gre of { - Just gre -> returnM (gre_name gre) ; - Nothing -> - - -- We allow qualified names on the command line to refer to - -- *any* name exported by any module in scope, just as if - -- there was an "import qualified M" declaration for every - -- module. - getModule `thenM` \ mod -> - if isQual rdr_name && mod == iNTERACTIVE then - -- This test is not expensive, - lookupQualifiedName rdr_name -- and only happens for failed lookups - else do - traceRn $ text "lookupGlobalOccRn" - unboundName rdr_name } - -lookupImportedName :: RdrName -> TcRnIf m n Name --- Lookup the occurrence of an imported name --- The RdrName is *always* qualified or Exact --- Treat it as an original name, and conjure up the Name --- Usually it's Exact or Orig, but it can be Qual if it --- comes from an hi-boot file. (This minor infelicity is --- just to reduce duplication in the parser.) -lookupImportedName rdr_name - | Just n <- isExact_maybe rdr_name - -- This happens in derived code - = returnM n - - -- Always Orig, even when reading a .hi-boot file | Just (rdr_mod, rdr_occ) <- isOrig_maybe rdr_name - = lookupOrig rdr_mod rdr_occ + = do { n <- lookupOrig rdr_mod rdr_occ; return (Just n) } | otherwise - = pprPanic "RnEnv.lookupImportedName" (ppr rdr_name) + = do { mb_gre <- lookupGreRn_maybe rdr_name + ; case mb_gre of + Nothing -> return Nothing + Just gre -> return (Just (gre_name gre)) } + unboundName :: RdrName -> RnM Name unboundName rdr_name = do { addErr (unknownNameErr rdr_name) ; env <- getGlobalRdrEnv; ; traceRn (vcat [unknownNameErr rdr_name, - ptext SLIT("Global envt is:"), + ptext (sLit "Global envt is:"), nest 3 (pprGlobalRdrEnv env)]) ; returnM (mkUnboundName rdr_name) } @@ -446,19 +419,30 @@ unboundName rdr_name -- Lookup in the Global RdrEnv of the module -------------------------------------------------- -lookupSrcOcc_maybe :: RdrName -> RnM (Maybe Name) --- No filter function; does not report an error on failure -lookupSrcOcc_maybe rdr_name - = do { mb_gre <- lookupGreRn_maybe rdr_name - ; case mb_gre of - Nothing -> returnM Nothing - Just gre -> returnM (Just (gre_name gre)) } - -------------------------- lookupGreRn_maybe :: RdrName -> RnM (Maybe GlobalRdrElt) -- Just look up the RdrName in the GlobalRdrEnv lookupGreRn_maybe rdr_name - = lookupGreRn_help rdr_name (lookupGRE_RdrName rdr_name) + = do { mGre <- lookupGreRn_help rdr_name (lookupGRE_RdrName rdr_name) + ; case mGre of + Just gre -> + case gre_prov gre of + LocalDef -> return () + Imported _ -> addUsedRdrName rdr_name + Nothing -> + return () + ; return mGre } + +addUsedRdrName :: RdrName -> RnM () +addUsedRdrName rdr + = do { env <- getGblEnv + ; updMutVar (tcg_used_rdrnames env) + (\s -> Set.insert rdr s) } + +addUsedRdrNames :: [RdrName] -> RnM () +addUsedRdrNames rdrs + = do { env <- getGblEnv + ; updMutVar (tcg_used_rdrnames env) + (\s -> foldr Set.insert s rdrs) } lookupGreRn :: RdrName -> RnM GlobalRdrElt -- If not found, add error message, and return a fake GRE @@ -503,7 +487,7 @@ lookupQualifiedName rdr_name | Just (mod,occ) <- isQual_maybe rdr_name -- Note: we want to behave as we would for a source file import here, -- and respect hiddenness of modules/packages, hence loadSrcInterface. - = loadSrcInterface doc mod False `thenM` \ iface -> + = loadSrcInterface doc mod False Nothing `thenM` \ iface -> case [ (mod,occ) | (mod,avails) <- mi_exports iface, @@ -517,69 +501,160 @@ lookupQualifiedName rdr_name | otherwise = pprPanic "RnEnv.lookupQualifiedName" (ppr rdr_name) where - doc = ptext SLIT("Need to find") <+> ppr rdr_name + doc = ptext (sLit "Need to find") <+> ppr rdr_name \end{code} -%********************************************************* -%* * - Fixities -%* * -%********************************************************* +lookupSigOccRn is used for type signatures and pragmas +Is this valid? + module A + import M( f ) + f :: Int -> Int + f x = x +It's clear that the 'f' in the signature must refer to A.f +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". \begin{code} -lookupLocalDataTcNames :: RdrName -> RnM [Name] +lookupSigOccRn :: Maybe NameSet -- Just ns => source file; these are the binders + -- in the same group + -- Nothing => hs-boot file; signatures without + -- binders are expected + -> Sig RdrName + -> Located RdrName -> RnM (Located Name) +lookupSigOccRn mb_bound_names sig + = wrapLocM $ \ rdr_name -> + do { mb_name <- lookupBindGroupOcc mb_bound_names (hsSigDoc sig) rdr_name + ; case mb_name of + Left err -> do { addErr err; return (mkUnboundName rdr_name) } + Right name -> return name } + +lookupBindGroupOcc :: Maybe NameSet -- Just ns => source file; these are the binders + -- in the same group + -- Nothing => hs-boot file; signatures without + -- binders are expected + -> SDoc + -> RdrName -> RnM (Either Message Name) +-- Looks up the RdrName, expecting it to resolve to one of the +-- bound names passed in. If not, return an appropriate error message +lookupBindGroupOcc mb_bound_names what rdr_name + = do { local_env <- getLocalRdrEnv + ; case lookupLocalRdrEnv local_env rdr_name of + Just n -> check_local_name n + Nothing -> do -- Not defined in a nested scope + + { env <- getGlobalRdrEnv + ; let gres = lookupGlobalRdrEnv env (rdrNameOcc rdr_name) + ; case (filter isLocalGRE gres) of + (gre:_) -> check_local_name (gre_name gre) + -- If there is more than one local GRE for the + -- same OccName, that will be reported separately + [] | null gres -> bale_out_with empty + | otherwise -> bale_out_with import_msg + }} + where + check_local_name name -- The name is in scope, and not imported + = case mb_bound_names of + Just bound_names | not (name `elemNameSet` bound_names) + -> bale_out_with local_msg + _other -> return (Right name) + + bale_out_with msg + = return (Left (sep [ ptext (sLit "The") <+> what + <+> ptext (sLit "for") <+> quotes (ppr rdr_name) + , nest 2 $ ptext (sLit "lacks an accompanying binding")] + $$ nest 2 msg)) + + local_msg = parens $ ptext (sLit "The") <+> what <+> ptext (sLit "must be given where") + <+> quotes (ppr rdr_name) <+> ptext (sLit "is declared") + + import_msg = parens $ ptext (sLit "You cannot give a") <+> what + <+> ptext (sLit "for an imported value") + +--------------- +lookupLocalDataTcNames :: NameSet -> SDoc -> RdrName -> RnM [Name] -- GHC extension: look up both the tycon and data con -- for con-like things -- Complain if neither is in scope -lookupLocalDataTcNames rdr_name +lookupLocalDataTcNames bound_names what rdr_name | Just n <- isExact_maybe rdr_name -- Special case for (:), which doesn't get into the GlobalRdrEnv = return [n] -- For this we don't need to try the tycon too | otherwise - = do { mb_gres <- mapM lookupGreLocalRn (dataTcOccs rdr_name) - ; case [gre_name gre | Just gre <- mb_gres] of - [] -> do { - -- run for error reporting - ; unboundName rdr_name - ; return [] } - names -> return names - } + = do { mb_gres <- mapM (lookupBindGroupOcc (Just bound_names) what) + (dataTcOccs rdr_name) + ; let (errs, names) = splitEithers mb_gres + ; when (null names) (addErr (head errs)) -- Bleat about one only + ; return names } +dataTcOccs :: RdrName -> [RdrName] +-- If the input is a data constructor, return both it and a type +-- constructor. This is useful when we aren't sure which we are +-- looking at. +dataTcOccs rdr_name + | Just n <- isExact_maybe rdr_name -- Ghastly special case + , n `hasKey` consDataConKey = [rdr_name] -- see note below + | isDataOcc occ = [rdr_name, rdr_name_tc] + | otherwise = [rdr_name] + where + occ = rdrNameOcc rdr_name + rdr_name_tc = setRdrNameSpace rdr_name tcName + +-- If the user typed "[]" or "(,,)", we'll generate an Exact RdrName, +-- and setRdrNameSpace generates an Orig, which is fine +-- But it's not fine for (:), because there *is* no corresponding type +-- constructor. If we generate an Orig tycon for GHC.Base.(:), it'll +-- appear to be in scope (because Orig's simply allocate a new name-cache +-- entry) and then we get an error when we use dataTcOccs in +-- TcRnDriver.tcRnGetInfo. Large sigh. +\end{code} + + +%********************************************************* +%* * + Fixities +%* * +%********************************************************* + +\begin{code} -------------------------------- -bindLocalFixities :: [FixitySig RdrName] -> (UniqFM (Located Fixity) -> RnM a) -> RnM a --- Used for nested fixity decls: --- bind the names that are in scope already; --- pass the rest to the continuation for later --- as a FastString->(Located Fixity) map --- --- No need to worry about type constructors here, --- Should check for duplicates? -bindLocalFixities fixes thing_inside - | null fixes = thing_inside emptyUFM - | otherwise = do ls <- mappM rn_sig fixes - let (now, later) = nowAndLater ls - extendFixityEnv now $ thing_inside later - where - rn_sig (FixitySig lv@(L loc v) fix) = do - vopt <- lookupBndrRn_maybe v - case vopt of - Just new_v -> returnM (Left (new_v, (FixItem (rdrNameOcc v) fix))) - Nothing -> returnM (Right (occNameFS $ rdrNameOcc v, (L loc fix))) - - nowAndLater :: [Either (Name, FixItem) (FastString, Located Fixity)] - -> ([(Name,FixItem)], UniqFM (Located Fixity)) - nowAndLater ls = - foldr (\ cur -> \ (now, later) -> - case cur of - Left (n, f) -> ((n, f) : now, later) - Right (fs, f) -> (now, addToUFM later fs f)) - ([], emptyUFM) ls +type FastStringEnv a = UniqFM a -- Keyed by FastString + + +emptyFsEnv :: FastStringEnv a +lookupFsEnv :: FastStringEnv a -> FastString -> Maybe a +extendFsEnv :: FastStringEnv a -> FastString -> a -> FastStringEnv a + +emptyFsEnv = emptyUFM +lookupFsEnv = lookupUFM +extendFsEnv = addToUFM + +-------------------------------- +type MiniFixityEnv = FastStringEnv (Located Fixity) + -- Mini fixity env for the names we're about + -- to bind, in a single binding group + -- + -- It is keyed by the *FastString*, not the *OccName*, because + -- the single fixity decl infix 3 T + -- affects both the data constructor T and the type constrctor T + -- + -- We keep the location so that if we find + -- a duplicate, we can report it sensibly +-------------------------------- -- Used for nested fixity decls to bind names along with their fixities. -- the fixities are given as a UFM from an OccName's FastString to a fixity decl -- Also check for unused binders bindLocalNamesFV_WithFixities :: [Name] - -> UniqFM (Located Fixity) + -> MiniFixityEnv -> RnM (a, FreeVars) -> RnM (a, FreeVars) bindLocalNamesFV_WithFixities names fixities thing_inside = bindLocalNamesFV names $ @@ -590,7 +665,7 @@ bindLocalNamesFV_WithFixities names fixities thing_inside boundFixities = foldr (\ name -> \ acc -> -- check whether this name has a fixity decl - case lookupUFM fixities (occNameFS (nameOccName name)) of + case lookupFsEnv fixities (occNameFS (nameOccName name)) of Just (L _ fix) -> (name, FixItem (nameOccName name) fix) : acc Nothing -> acc) [] names -- bind the names; extend the fixity env; do the thing inside @@ -643,33 +718,12 @@ lookupFixityRn name returnM (mi_fix_fn iface (nameOccName name)) } where - doc = ptext SLIT("Checking fixity for") <+> ppr name + doc = ptext (sLit "Checking fixity for") <+> ppr name --------------- lookupTyFixityRn :: Located Name -> RnM Fixity -lookupTyFixityRn (L loc n) = lookupFixityRn n - ---------------- -dataTcOccs :: RdrName -> [RdrName] --- If the input is a data constructor, return both it and a type --- constructor. This is useful when we aren't sure which we are --- looking at. -dataTcOccs rdr_name - | Just n <- isExact_maybe rdr_name -- Ghastly special case - , n `hasKey` consDataConKey = [rdr_name] -- see note below - | isDataOcc occ = [rdr_name_tc, rdr_name] - | otherwise = [rdr_name] - where - occ = rdrNameOcc rdr_name - rdr_name_tc = setRdrNameSpace rdr_name tcName +lookupTyFixityRn (L _ n) = lookupFixityRn n --- If the user typed "[]" or "(,,)", we'll generate an Exact RdrName, --- and setRdrNameSpace generates an Orig, which is fine --- But it's not fine for (:), because there *is* no corresponding type --- constructor. If we generate an Orig tycon for GHC.Base.(:), it'll --- appear to be in scope (because Orig's simply allocate a new name-cache --- entry) and then we get an error when we use dataTcOccs in --- TcRnDriver.tcRnGetInfo. Large sigh. \end{code} %************************************************************************ @@ -807,13 +861,15 @@ bindTyVarsRn :: SDoc -> [LHsTyVarBndr RdrName] -> RnM a -- Haskell-98 binding of type variables; e.g. within a data type decl bindTyVarsRn doc_str tyvar_names enclosed_scope - = let - located_tyvars = hsLTyVarLocNames tyvar_names - in - bindLocatedLocalsRn doc_str located_tyvars $ \ names -> - enclosed_scope (zipWith replace tyvar_names names) - where - replace (L loc n1) n2 = L loc (replaceTyVarName n1 n2) + = bindLocatedLocalsRn doc_str located_tyvars $ \ names -> + do { kind_sigs_ok <- doptM Opt_KindSignatures + ; checkM (null kinded_tyvars || kind_sigs_ok) + (mapM_ (addErr . kindSigErr) kinded_tyvars) + ; enclosed_scope (zipWith replace tyvar_names names) } + where + replace (L loc n1) n2 = L loc (replaceTyVarName n1 n2) + located_tyvars = hsLTyVarLocNames tyvar_names + kinded_tyvars = [n | L _ (KindedTyVar n _) <- tyvar_names] bindPatSigTyVars :: [LHsType RdrName] -> ([Name] -> RnM a) -> RnM a -- Find the type variables in the pattern type @@ -885,15 +941,34 @@ checkShadowedNames doc_str (global_env,local_env) loc_rdr_names ; mappM_ check_shadow loc_rdr_names } where check_shadow (loc, occ) - | Just n <- mb_local = complain [ptext SLIT("bound at") <+> ppr loc] - | not (null gres) = complain (map pprNameProvenance gres) - | otherwise = return () + | startsWithUnderscore occ = return () -- Do not report shadowing for "_x" + -- See Trac #3262 + | Just n <- mb_local = complain [ptext (sLit "bound at") <+> ppr (nameSrcLoc n)] + | otherwise = do { gres' <- filterM is_shadowed_gre gres + ; complain (map pprNameProvenance gres') } where + complain [] = return () complain pp_locs = addWarnAt loc (shadowedNameWarn doc_str occ pp_locs) mb_local = lookupLocalRdrOcc local_env occ gres = lookupGRE_RdrName (mkRdrUnqual occ) global_env -- Make an Unqualified RdrName and look that up, so that -- we don't find any GREs that are in scope qualified-only + + is_shadowed_gre :: GlobalRdrElt -> RnM Bool + -- Returns False for record selectors that are shadowed, when + -- punning or wild-cards are on (cf Trac #2723) + is_shadowed_gre gre@(GRE { gre_par = ParentIs _ }) + = do { dflags <- getDOpts + ; if (dopt Opt_RecordPuns dflags || dopt Opt_RecordWildCards dflags) + then do { is_fld <- is_rec_fld gre; return (not is_fld) } + else return True } + is_shadowed_gre _other = return True + + is_rec_fld gre -- Return True for record selector ids + | isLocalGRE gre = do { RecFields _ fld_set <- getRecFieldEnv + ; return (gre_name gre `elemNameSet` fld_set) } + | otherwise = do { sel_id <- tcLookupField (gre_name gre) + ; return (isRecordSelector sel_id) } \end{code} @@ -905,11 +980,10 @@ checkShadowedNames doc_str (global_env,local_env) loc_rdr_names \begin{code} -- A useful utility -mapFvRn f xs = mappM f xs `thenM` \ stuff -> - let - (ys, fvs_s) = unzip stuff - in - returnM (ys, plusFVs fvs_s) +mapFvRn :: (a -> RnM (b, FreeVars)) -> [a] -> RnM ([b], FreeVars) +mapFvRn f xs = do stuff <- mappM f xs + case unzip stuff of + (ys, fvs_s) -> returnM (ys, plusFVs fvs_s) -- because some of the rename functions are CPSed: -- maps the function across the list from left to right; @@ -936,37 +1010,33 @@ warnUnusedModules mods = ifOptM Opt_WarnUnusedImports (mappM_ bleat mods) where bleat (mod,loc) = addWarnAt loc (mk_warn mod) - mk_warn m = vcat [ptext SLIT("Module") <+> quotes (ppr m) + mk_warn m = vcat [ptext (sLit "Module") <+> quotes (ppr m) <+> text "is imported, but nothing from it is used,", - nest 2 (ptext SLIT("except perhaps instances visible in") + nest 2 (ptext (sLit "except perhaps instances visible in") <+> quotes (ppr m)), - ptext SLIT("To suppress this warning, use:") - <+> ptext SLIT("import") <+> ppr m <> parens empty ] + ptext (sLit "To suppress this warning, use:") + <+> ptext (sLit "import") <+> ppr m <> parens empty ] warnUnusedImports, warnUnusedTopBinds :: [GlobalRdrElt] -> RnM () warnUnusedImports gres = ifOptM Opt_WarnUnusedImports (warnUnusedGREs gres) warnUnusedTopBinds gres = ifOptM Opt_WarnUnusedBinds (warnUnusedGREs gres) -warnUnusedLocalBinds, warnUnusedMatches :: [Name] -> RnM (a, FreeVars) -> RnM (a, FreeVars) +warnUnusedLocalBinds, warnUnusedMatches :: [Name] -> FreeVars -> RnM () warnUnusedLocalBinds = check_unused Opt_WarnUnusedBinds warnUnusedMatches = check_unused Opt_WarnUnusedMatches -check_unused :: DynFlag -> [Name] -> RnM (a, FreeVars) -> RnM (a, FreeVars) -check_unused flag names thing_inside - = do { (res, res_fvs) <- thing_inside - - -- Warn about unused names - ; ifOptM flag (warnUnusedLocals (filterOut (`elemNameSet` res_fvs) names)) - - -- And return - ; return (res, res_fvs) } +check_unused :: DynFlag -> [Name] -> FreeVars -> RnM () +check_unused flag bound_names used_names + = ifOptM flag (warnUnusedLocals (filterOut (`elemNameSet` used_names) bound_names)) ------------------------- -- Helpers +warnUnusedGREs :: [GlobalRdrElt] -> RnM () warnUnusedGREs gres = warnUnusedBinds [(n,p) | GRE {gre_name = n, gre_prov = p} <- gres] +warnUnusedLocals :: [Name] -> RnM () warnUnusedLocals names = warnUnusedBinds [(n,LocalDef) | n<-names] @@ -976,14 +1046,14 @@ warnUnusedBinds names = mappM_ warnUnusedName (filter reportable names) | isWiredInName name = False -- Don't report unused wired-in names -- Otherwise we get a zillion warnings -- from Data.Tuple - | otherwise = reportIfUnused (nameOccName name) + | otherwise = not (startsWithUnderscore (nameOccName name)) ------------------------- warnUnusedName :: (Name, Provenance) -> RnM () warnUnusedName (name, LocalDef) - = addUnusedWarning name (srcLocSpan (nameSrcLoc name)) - (ptext SLIT("Defined but not used")) + = addUnusedWarning name (nameSrcSpan name) + (ptext (sLit "Defined but not used")) warnUnusedName (name, Imported is) = mapM_ warn is @@ -992,8 +1062,9 @@ warnUnusedName (name, Imported is) where span = importSpecLoc spec pp_mod = quotes (ppr (importSpecModule spec)) - msg = ptext SLIT("Imported from") <+> pp_mod <+> ptext SLIT("but not used") + msg = ptext (sLit "Imported from") <+> pp_mod <+> ptext (sLit "but not used") +addUnusedWarning :: Name -> SrcSpan -> SDoc -> RnM () addUnusedWarning name span msg = addWarnAt span $ sep [msg <> colon, @@ -1002,47 +1073,73 @@ addUnusedWarning name span msg \end{code} \begin{code} +addNameClashErrRn :: RdrName -> [GlobalRdrElt] -> RnM () addNameClashErrRn rdr_name names - = addErr (vcat [ptext SLIT("Ambiguous occurrence") <+> quotes (ppr rdr_name), - ptext SLIT("It could refer to") <+> vcat (msg1 : msgs)]) + = addErr (vcat [ptext (sLit "Ambiguous occurrence") <+> quotes (ppr rdr_name), + ptext (sLit "It could refer to") <+> vcat (msg1 : msgs)]) where (np1:nps) = names - msg1 = ptext SLIT("either") <+> mk_ref np1 - msgs = [ptext SLIT(" or") <+> mk_ref np | np <- nps] + msg1 = ptext (sLit "either") <+> mk_ref np1 + msgs = [ptext (sLit " or") <+> mk_ref np | np <- nps] mk_ref gre = quotes (ppr (gre_name gre)) <> comma <+> pprNameProvenance gre +shadowedNameWarn :: SDoc -> OccName -> [SDoc] -> SDoc shadowedNameWarn doc occ shadowed_locs - = sep [ptext SLIT("This binding for") <+> quotes (ppr occ) - <+> ptext SLIT("shadows the existing binding") <> plural shadowed_locs, + = sep [ptext (sLit "This binding for") <+> quotes (ppr occ) + <+> ptext (sLit "shadows the existing binding") <> plural shadowed_locs, nest 2 (vcat shadowed_locs)] $$ doc +unknownNameErr :: RdrName -> SDoc unknownNameErr rdr_name - = sep [ptext SLIT("Not in scope:"), - nest 2 $ pprNonVarNameSpace (occNameSpace (rdrNameOcc rdr_name)) - <+> quotes (ppr rdr_name)] + = vcat [ hang (ptext (sLit "Not in scope:")) + 2 (pprNonVarNameSpace (occNameSpace (rdrNameOcc rdr_name)) + <+> quotes (ppr rdr_name)) + , extra ] + where + extra | rdr_name == forall_tv_RDR = perhapsForallMsg + | otherwise = empty + +perhapsForallMsg :: SDoc +perhapsForallMsg + = vcat [ ptext (sLit "Perhaps you intended to use -XRankNTypes or similar flag") + , ptext (sLit "to enable explicit-forall syntax: forall . ")] +unknownSubordinateErr :: SDoc -> RdrName -> SDoc unknownSubordinateErr doc op -- Doc is "method of class" or -- "field of constructor" - = quotes (ppr op) <+> ptext SLIT("is not a (visible)") <+> doc + = quotes (ppr op) <+> ptext (sLit "is not a (visible)") <+> doc +badOrigBinding :: RdrName -> SDoc badOrigBinding name - = ptext SLIT("Illegal binding of built-in syntax:") <+> ppr (rdrNameOcc name) + = ptext (sLit "Illegal binding of built-in syntax:") <+> ppr (rdrNameOcc name) -- The rdrNameOcc is because we don't want to print Prelude.(,) dupNamesErr :: Outputable n => (n -> SrcSpan) -> SDoc -> [n] -> RnM () dupNamesErr get_loc descriptor names = addErrAt big_loc $ - vcat [ptext SLIT("Conflicting definitions for") <+> quotes (ppr (head names)), + vcat [ptext (sLit "Conflicting definitions for") <+> quotes (ppr (head names)), locations, descriptor] where locs = map get_loc names big_loc = foldr1 combineSrcSpans locs one_line = isOneLineSpan big_loc locations | one_line = empty - | otherwise = ptext SLIT("Bound at:") <+> + | otherwise = ptext (sLit "Bound at:") <+> vcat (map ppr (sortLe (<=) locs)) +kindSigErr :: Outputable a => a -> SDoc +kindSigErr thing + = hang (ptext (sLit "Illegal kind signature for") <+> quotes (ppr thing)) + 2 (ptext (sLit "Perhaps you intended to use -XKindSignatures")) + + +badQualBndrErr :: RdrName -> SDoc badQualBndrErr rdr_name - = ptext SLIT("Qualified name in binding position:") <+> ppr rdr_name + = ptext (sLit "Qualified name in binding position:") <+> ppr rdr_name + +opDeclErr :: RdrName -> SDoc +opDeclErr n + = hang (ptext (sLit "Illegal declaration of a type or class operator") <+> quotes (ppr n)) + 2 (ptext (sLit "Use -XTypeOperators to declare operators in type and declarations")) \end{code}