\begin{code}
module RnEnv (
newTopSrcBinder, lookupFamInstDeclBndr,
- lookupLocatedBndrRn, lookupBndrRn,
lookupLocatedTopBndrRn, lookupTopBndrRn,
lookupLocatedOccRn, lookupOccRn,
- lookupLocatedGlobalOccRn, lookupGlobalOccRn,
- lookupLocalDataTcNames, lookupSrcOcc_maybe,
- lookupFixityRn, lookupTyFixityRn, lookupLocatedSigOccRn,
- lookupLocatedInstDeclBndr,
- lookupSyntaxName, lookupSyntaxTable, lookupImportedName,
- lookupGreRn, lookupGreRn_maybe,
-
- newLocalsRn, newIPNameRn,
- bindLocalNames, bindLocalNamesFV,
+ lookupGlobalOccRn, lookupGlobalOccRn_maybe,
+ lookupLocalDataTcNames, lookupSigOccRn,
+ lookupFixityRn, lookupTyFixityRn,
+ lookupInstDeclBndr, lookupSubBndr, lookupConstructorFields,
+ lookupSyntaxName, lookupSyntaxTable,
+ lookupGreRn, lookupGreLocalRn, lookupGreRn_maybe,
+ getLookupOccRn, addUsedRdrNames,
+
+ newLocalBndrRn, newLocalBndrsRn, newIPNameRn,
+ bindLocalName, bindLocalNames, bindLocalNamesFV,
+ MiniFixityEnv, emptyFsEnv, extendFsEnv, lookupFsEnv,
+ addLocalFixities,
bindLocatedLocalsFV, bindLocatedLocalsRn,
bindSigTyVarsFV, bindPatSigTyVars, bindPatSigTyVarsFV,
- bindTyVarsRn, extendTyVarEnvFVRn,
- bindLocalFixities,
+ bindTyVarsRn, bindTyVarsFV, extendTyVarEnvFVRn,
- checkDupNames, mapFvRn,
- warnUnusedMatches, warnUnusedModules, warnUnusedImports,
+ checkDupRdrNames, checkDupAndShadowedRdrNames,
+ checkDupNames, checkDupAndShadowedNames,
+ addFvRn, mapFvRn, mapMaybeFvRn, mapFvRnCPS,
+ warnUnusedMatches,
warnUnusedTopBinds, warnUnusedLocalBinds,
- dataTcOccs, unknownNameErr,
+ dataTcOccs, unknownNameErr, kindSigErr, perhapsForallMsg
) 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 TcEnv ( getHetMetLevel )
+import HsSyn
import RdrHsSyn ( extractHsTyRdrTyVars )
-import RdrName ( RdrName, isQual, isUnqual, isOrig_maybe,
- isQual_maybe,
- 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 RdrName
+import HscTypes ( availNames, ModIface(..), FixItem(..), lookupFixity)
+import TcEnv ( tcLookupDataCon, tcLookupField, isBrackStage )
import TcRnMonad
-import Name ( Name, nameIsLocalOrFrom, mkInternalName, isWiredInName,
- nameSrcLoc, nameOccName, nameModule, isExternalName )
+import Id ( isRecordSelector )
+import Name
import NameSet
-import OccName ( tcName, isDataOcc, pprNonVarNameSpace, occNameSpace,
- reportIfUnused )
-import Module ( Module, ModuleName )
-import PrelNames ( mkUnboundName, rOOT_MAIN, iNTERACTIVE, consDataConKey, hasKey )
-import UniqSupply
-import BasicTypes ( IPName, mapIPName )
-import SrcLoc ( SrcSpan, srcSpanStart, Located(..), eqLocated, unLoc,
- srcLocSpan, getLoc, combineSrcSpans, isOneLineSpan )
+import NameEnv
+import Module ( ModuleName, moduleName )
+import UniqFM
+import DataCon ( dataConFieldLabels )
+import PrelNames ( mkUnboundName, rOOT_MAIN, consDataConKey, forall_tv_RDR )
+import Unique
+import BasicTypes
+import ErrUtils ( Message )
+import SrcLoc
import Outputable
-import Util ( sortLe )
+import Util
+import Maybes
import ListSetOps ( removeDups )
-import List ( nubBy )
-import Monad ( when )
import DynFlags
+import FastString
+import Control.Monad
+import Data.List
+import qualified Data.Set as Set
+\end{code}
+
+\begin{code}
+-- XXX
+thenM :: Monad a => a b -> (b -> a c) -> a c
+thenM = (>>=)
\end{code}
%*********************************************************
%*********************************************************
\begin{code}
-newTopSrcBinder :: Module -> Located RdrName -> RnM Name
-newTopSrcBinder this_mod (L loc rdr_name)
+newTopSrcBinder :: Located RdrName -> RnM Name
+newTopSrcBinder (L loc rdr_name)
| Just name <- isExact_maybe rdr_name
= -- This is here to catch
-- (a) Exact-name binders created by Template Haskell
-- data T = (,) Int Int
-- unless we are in GHC.Tup
ASSERT2( isExternalName name, ppr name )
- do { checkM (this_mod == nameModule name)
+ do { this_mod <- getModule
+ ; unless (this_mod == nameModule name)
(addErrAt loc (badOrigBinding rdr_name))
; return name }
| Just (rdr_mod, rdr_occ) <- isOrig_maybe rdr_name
- = do { checkM (rdr_mod == this_mod || rdr_mod == rOOT_MAIN)
+ = do { this_mod <- getModule
+ ; unless (rdr_mod == this_mod || rdr_mod == rOOT_MAIN)
(addErrAt loc (badOrigBinding rdr_name))
-- When reading External Core we get Orig names as binders,
-- but they should agree with the module gotten from the monad
-- 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 (srcSpanStart loc) }
+ ; newGlobalBinder rdr_mod rdr_occ loc }
--TODO, should pass the whole span
| otherwise
- = do { checkM (not (isQual rdr_name))
+ = do { unless (not (isQual 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) (srcSpanStart 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
+ do { this_mod <- getModule
+ ; newGlobalBinder this_mod (rdrNameOcc rdr_name) loc } }
\end{code}
%*********************************************************
Looking up a name in the RnEnv.
-\begin{code}
-lookupLocatedBndrRn :: Located RdrName -> RnM (Located Name)
-lookupLocatedBndrRn = wrapLocM lookupBndrRn
+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.
-lookupBndrRn :: RdrName -> RnM Name
--- NOTE: assumes that the SrcSpan of the binder has already been setSrcSpan'd
-lookupBndrRn rdr_name
- = getLocalRdrEnv `thenM` \ local_env ->
- case lookupLocalRdrEnv local_env rdr_name of
- Just name -> returnM name
- Nothing -> lookupTopBndrRn rdr_name
+\begin{code}
+lookupTopBndrRn :: RdrName -> RnM Name
+lookupTopBndrRn n = do nopt <- lookupTopBndrRn_maybe n
+ case nopt of
+ Just n' -> return n'
+ Nothing -> do traceRn $ text "lookupTopBndrRn"
+ unboundName WL_LocalTop n
lookupLocatedTopBndrRn :: Located RdrName -> RnM (Located Name)
lookupLocatedTopBndrRn = wrapLocM lookupTopBndrRn
-lookupTopBndrRn :: RdrName -> RnM Name
+lookupTopBndrRn_maybe :: RdrName -> RnM (Maybe Name)
-- Look up a top-level source-code binder. We may be looking up an unqualified 'f',
-- and there may be several imported 'f's too, which must not confuse us.
-- For example, this is OK:
-- The Haskell parser checks for the illegal qualified name in Haskell
-- source files, so we don't need to do so here.
-lookupTopBndrRn rdr_name
+lookupTopBndrRn_maybe rdr_name
| Just name <- isExact_maybe rdr_name
- = returnM name
+ = return (Just name)
| Just (rdr_mod, rdr_occ) <- isOrig_maybe rdr_name
-- This deals with the case of derived bindings, where
-- we don't bother to call newTopSrcBinder first
-- We assume there is no "parent" name
= do { loc <- getSrcSpanM
- ; newGlobalBinder rdr_mod rdr_occ (srcSpanStart loc) }
+ ; n <- newGlobalBinder rdr_mod rdr_occ loc
+ ; 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 <- xoptM Opt_TypeOperators
+ ; unless op_ok (addErr (opDeclErr rdr_name)) })
+
+ ; mb_gre <- lookupGreLocalRn rdr_name
; case mb_gre of
- Nothing -> do
- traceRn $ text "lookupTopBndrRn"
- unboundName rdr_name
- Just gre -> returnM (gre_name gre) }
+ Nothing -> return Nothing
+ Just gre -> return (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
-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.
-
-lookupLocatedInstDeclBndr :: Name -> Located RdrName -> RnM (Located Name)
-lookupLocatedInstDeclBndr cls rdr = wrapLocM (lookupInstDeclBndr cls) rdr
+-----------------------------------------------
lookupInstDeclBndr :: 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
-- ^^^^ called on this
-- Regardless of how many unqualified fmaps are in scope, we want
-- the one that comes from the Functor class.
-lookupInstDeclBndr 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@(GRE {gre_par = ParentIs n}) = cls_name == n
- ; is_op other = False
- ; 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)
- ; traceRn (text "lookupInstDeclBndr" <+> ppr rdr_name)
- ; return (mkUnboundName rdr_name) } }
+--
+-- 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
+ = do { when (isQual rdr)
+ (addErr (badQualBndrErr rdr))
+ -- In an instance decl you aren't allowed
+ -- to use a qualified name for the method
+ -- (Although it'd make perfect sense.)
+ ; lookupSubBndr (ParentIs cls) doc rdr }
+ where
+ doc = ptext (sLit "method of class") <+> quotes (ppr cls)
+
+-----------------------------------------------
+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 { RecFields field_env _ <- getRecFieldEnv
+ ; return (lookupNameEnv field_env con_name `orElse` []) }
+ else
+ do { con <- tcLookupDataCon con_name
+ ; return (dataConFieldLabels con) } }
+
+-----------------------------------------------
+-- Used for record construction and pattern matching
+-- 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.
+
+lookupSubBndr :: Parent -- NoParent => just look it up as usual
+ -- ParentIs p => use p to disambiguate
+ -> SDoc -> RdrName
+ -> RnM Name
+lookupSubBndr parent doc rdr_name
+ | Just n <- isExact_maybe rdr_name -- This happens in derived code
+ = return n
- | 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
+ | Just (rdr_mod, rdr_occ) <- isOrig_maybe rdr_name
+ = lookupOrig rdr_mod rdr_occ
+
+ | otherwise -- Find all the things the rdr-name maps to
+ = do { -- and pick the one with the right parent name
+ ; env <- getGlobalRdrEnv
+ ; let gres = lookupGlobalRdrEnv env (rdrNameOcc rdr_name)
+ ; case pick parent gres 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] -> do { addUsedRdrNames (used_rdr_names gre)
+ ; return (gre_name gre) }
+ [] -> do { addErr (unknownSubordinateErr doc rdr_name)
+ ; traceRn (text "RnEnv.lookup_sub_bndr" <+> (ppr rdr_name $$ ppr gres))
+ ; return (mkUnboundName rdr_name) }
+ gres -> do { addNameClashErrRn rdr_name gres
+ ; return (gre_name (head gres)) } }
+ where
+ pick NoParent gres -- Normal lookup
+ = pickGREs rdr_name gres
+ pick (ParentIs p) gres -- Disambiguating lookup
+ | isUnqual rdr_name = filter (right_parent p) gres
+ | otherwise = filter (right_parent p) (pickGREs rdr_name gres)
+
+ right_parent p (GRE { gre_par = ParentIs p' }) = p==p'
+ right_parent _ _ = False
+
+ -- Note [Usage for sub-bndrs]
+ used_rdr_names gre
+ | isQual rdr_name = [rdr_name]
+ | otherwise = case gre_prov gre of
+ LocalDef -> [rdr_name]
+ Imported is -> map mk_qual_rdr is
+ mk_qual_rdr imp_spec = mkRdrQual (is_as (is_decl imp_spec)) rdr_occ
+ rdr_occ = rdrNameOcc 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.
+-- 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'.
--
--- 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.
---
-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
+\end{code}
+
+Note [Usage for sub-bndrs]
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+If you have this
+ import qualified M( C( f ) )
+ intance M.C T where
+ f x = x
+then is the qualified import M.f used? Obviously yes.
+But the RdrName used in the instance decl is unqualified. In effect,
+we fill in the qualification by looking for f's whose class is M.C
+But when adding to the UsedRdrNames we must make that qualification
+explicit, otherwise we get "Redundant import of M.C".
--------------------------------------------------
-- Occurrences
--------------------------------------------------
+\begin{code}
+getLookupOccRn :: RnM (Name -> Maybe Name)
+getLookupOccRn
+ = getLocalRdrEnv `thenM` \ local_env ->
+ return (lookupLocalRdrOcc local_env . nameOccName)
+
lookupLocatedOccRn :: Located RdrName -> RnM (Located Name)
lookupLocatedOccRn = wrapLocM lookupOccRn
-- lookupOccRn looks up an occurrence of a RdrName
lookupOccRn :: RdrName -> RnM Name
lookupOccRn rdr_name
- = getLocalRdrEnv `thenM` \ local_env ->
- case lookupLocalRdrEnv local_env rdr_name of
- Just name -> returnM name
- Nothing -> lookupGlobalOccRn rdr_name
+ = do { local_env <- getLocalRdrEnv
+ ; case lookupLocalRdrEnv local_env rdr_name of {
+ Just name -> return name ;
+ Nothing -> do
+
+ { 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
+ ; is_ghci <- getIsGHCi
+ -- This test is not expensive,
+ -- and only happens for failed lookups
+ ; if isQual rdr_name && allow_qual && is_ghci
+ then lookupQualifiedName rdr_name
+ else unboundName WL_Any rdr_name } } } } }
-lookupLocatedGlobalOccRn :: Located RdrName -> RnM (Located Name)
-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.
lookupGlobalOccRn rdr_name
- | not (isSrcRdrName rdr_name)
- = lookupImportedName rdr_name
+ = do { mb_name <- lookupGlobalOccRn_maybe rdr_name
+ ; case mb_name of
+ Just n -> return n
+ Nothing -> unboundName WL_Global 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:"),
- nest 3 (pprGlobalRdrEnv env)])
- ; returnM (mkUnboundName 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
Just gre -> return gre ;
Nothing -> do
{ traceRn $ text "lookupGreRn"
- ; name <- unboundName rdr_name
+ ; name <- unboundName WL_Global rdr_name
; return (GRE { gre_name = name, gre_par = NoParent,
gre_prov = LocalDef }) }}}
lookupGreRn_help rdr_name lookup
= do { env <- getGlobalRdrEnv
; case lookup env of
- [] -> returnM Nothing
- [gre] -> returnM (Just gre)
+ [] -> return Nothing
+ [gre] -> do { addUsedRdrName gre rdr_name
+ ; return (Just gre) }
gres -> do { addNameClashErrRn rdr_name gres
- ; returnM (Just (head gres)) } }
+ ; return (Just (head gres)) } }
+
+addUsedRdrName :: GlobalRdrElt -> RdrName -> RnM ()
+-- Record usage of imported RdrNames
+addUsedRdrName gre rdr
+ | isLocalGRE gre = return ()
+ | otherwise = do { env <- getGblEnv
+ ; updMutVar (tcg_used_rdrnames env)
+ (\s -> Set.insert rdr s) }
+
+addUsedRdrNames :: [RdrName] -> RnM ()
+-- Record used sub-binders
+-- We don't check for imported-ness here, because it's inconvenient
+-- and not stritly necessary.
+addUsedRdrNames rdrs
+ = do { env <- getGblEnv
+ ; updMutVar (tcg_used_rdrnames env)
+ (\s -> foldr Set.insert s rdrs) }
------------------------------
-- GHCi support
| 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,
name == occ ] of
((mod,occ):ns) -> ASSERT (null ns)
lookupOrig mod occ
- _ -> unboundName rdr_name
+ _ -> unboundName WL_Any 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
-%* *
-%*********************************************************
+Note [Looking up signature names]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+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 => these are the binders
+ -- in the same group
+ -- Nothing => signatures without
+ -- binders are expected
+ -- (a) top-level (SPECIALISE prags)
+ -- (b) class decls
+ -- (c) hs-boot files
+ -> 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 -- See notes on the (Maybe NameSet)
+ -> SDoc -- in lookupSigOccRn
+ -> 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
+--
+-- See Note [Looking up signature names]
+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 'f', that will be reported separately
+ -- as a duplicate top-level binding for 'f'
+ [] | 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 { addErr (unknownNameErr 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] -> RnM a -> RnM a
--- Used for nested fixity decls
--- No need to worry about type constructors here,
--- Should check for duplicates but we don't
-bindLocalFixities fixes thing_inside
- | null fixes = thing_inside
- | otherwise = mappM rn_sig fixes `thenM` \ new_bit ->
- extendFixityEnv new_bit thing_inside
+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
+
+addLocalFixities :: MiniFixityEnv -> [Name] -> RnM a -> RnM a
+addLocalFixities mini_fix_env names thing_inside
+ = extendFixityEnv (mapCatMaybes find_fixity names) thing_inside
where
- rn_sig (FixitySig lv@(L loc v) fix)
- = addLocM lookupBndrRn lv `thenM` \ new_v ->
- returnM (new_v, (FixItem (rdrNameOcc v) fix loc))
+ find_fixity name
+ = case lookupFsEnv mini_fix_env (occNameFS occ) of
+ Just (L _ fix) -> Just (name, FixItem occ fix)
+ Nothing -> Nothing
+ where
+ occ = nameOccName name
\end{code}
--------------------------------
\begin{code}
lookupFixityRn :: Name -> RnM Fixity
lookupFixityRn name
- = getModule `thenM` \ this_mod ->
+ = getModule `thenM` \ this_mod ->
if nameIsLocalOrFrom this_mod name
- then -- It's defined in this module
- getFixityEnv `thenM` \ local_fix_env ->
- traceRn (text "lookupFixityRn" <+> (ppr name $$ ppr local_fix_env)) `thenM_`
- returnM (lookupFixity local_fix_env name)
-
+ then do -- It's defined in this module
+ local_fix_env <- getFixityEnv
+ traceRn (text "lookupFixityRn: looking up name in local environment:" <+>
+ vcat [ppr name, ppr local_fix_env])
+ return $ lookupFixity local_fix_env name
else -- It's imported
-- For imported names, we have to get their fixities by doing a
-- loadInterfaceForName, and consulting the Ifaces that comes back
--
-- loadInterfaceForName will find B.hi even if B is a hidden module,
-- and that's what we want.
- loadInterfaceForName doc name `thenM` \ iface ->
- returnM (mi_fix_fn iface (nameOccName name))
+ loadInterfaceForName doc name `thenM` \ iface -> do {
+ traceRn (text "lookupFixityRn: looking up name in iface cache and found:" <+>
+ vcat [ppr name, ppr $ mi_fix_fn iface (nameOccName name)]);
+ return (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)
- = do { glaExts <- doptM Opt_GlasgowExts
- ; when (not glaExts) (addWarnAt loc (infixTyConWarn n))
- ; lookupFixityRn n }
+lookupTyFixityRn (L _ 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
-
--- 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}
%************************************************************************
%* *
Rebindable names
Dealing with rebindable syntax is driven by the
- Opt_NoImplicitPrelude dynamic flag.
+ Opt_RebindableSyntax dynamic flag.
In "deriving" code we don't want to use rebindable syntax
so we switch off the flag locally
* "do" notation
We store the relevant Name in the HsSyn tree, in
- * HsIntegral/HsFractional
+ * HsIntegral/HsFractional/HsIsString
* NegApp
* NPlusKPat
* HsDo
lookupSyntaxName :: Name -- The standard name
-> RnM (SyntaxExpr Name, FreeVars) -- Possibly a non-standard name
lookupSyntaxName std_name
- = doptM Opt_ImplicitPrelude `thenM` \ implicit_prelude ->
- if implicit_prelude then normal_case
- else
- -- Get the similarly named thing from the local environment
- lookupOccRn (mkRdrUnqual (nameOccName std_name)) `thenM` \ usr_name ->
- returnM (HsVar usr_name, unitFV usr_name)
- where
- normal_case = returnM (HsVar std_name, emptyFVs)
+ = do ec <- getHetMetLevel
+ std_name' <- return $ setNameDepth (length ec) std_name
+ rebindable_on <- xoptM Opt_RebindableSyntax
+ if not rebindable_on
+ then return (HsVar std_name', emptyFVs)
+ else do usr_name <- lookupOccRn (mkRdrUnqual (nameOccName std_name'))
+ return (HsVar usr_name, unitFV usr_name)
+ -- Get the similarly named thing from the local environment
lookupSyntaxTable :: [Name] -- Standard names
-> RnM (SyntaxTable Name, FreeVars) -- See comments with HsExpr.ReboundNames
lookupSyntaxTable std_names
- = doptM Opt_ImplicitPrelude `thenM` \ implicit_prelude ->
- if implicit_prelude then normal_case
+ = xoptM Opt_RebindableSyntax `thenM` \ rebindable_on ->
+ if not rebindable_on then normal_case
else
-- Get the similarly named thing from the local environment
- mappM (lookupOccRn . mkRdrUnqual . nameOccName) std_names `thenM` \ usr_names ->
+ mapM (lookupOccRn . mkRdrUnqual . nameOccName) std_names `thenM` \ usr_names ->
- returnM (std_names `zip` map HsVar usr_names, mkFVs usr_names)
+ return (std_names `zip` map HsVar usr_names, mkFVs usr_names)
where
- normal_case = returnM (std_names `zip` map HsVar std_names, emptyFVs)
+ normal_case = return (std_names `zip` map HsVar std_names, emptyFVs)
\end{code}
%*********************************************************
\begin{code}
-newLocalsRn :: [Located RdrName] -> RnM [Name]
-newLocalsRn rdr_names_w_loc
- = newUniqueSupply `thenM` \ us ->
- returnM (zipWith mk rdr_names_w_loc (uniqsFromSupply us))
- where
- mk (L loc rdr_name) uniq
- | Just name <- isExact_maybe rdr_name = name
- -- This happens in code generated by Template Haskell
- | 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)
-
-bindLocatedLocalsRn :: SDoc -- Documentation string for error message
- -> [Located RdrName]
+newLocalBndrRn :: Located RdrName -> RnM Name
+-- Used for non-top-level binders. These should
+-- never be qualified.
+newLocalBndrRn (L loc rdr_name)
+ | Just name <- isExact_maybe rdr_name
+ = return name -- This happens in code generated by Template Haskell
+ -- although I'm not sure why. Perhpas it's the call
+ -- in RnPat.newName LetMk?
+ | otherwise
+ = do { unless (isUnqual rdr_name)
+ (addErrAt loc (badQualBndrErr rdr_name))
+ ; uniq <- newUnique
+ ; return (mkInternalName uniq (rdrNameOcc rdr_name) loc) }
+
+newLocalBndrsRn :: [Located RdrName] -> RnM [Name]
+newLocalBndrsRn = mapM newLocalBndrRn
+
+---------------------
+bindLocatedLocalsRn :: [Located RdrName]
-> ([Name] -> RnM a)
-> RnM a
-bindLocatedLocalsRn doc_str rdr_names_w_loc enclosed_scope
- = -- Check for duplicate names
- checkDupNames doc_str rdr_names_w_loc `thenM_`
-
- -- Warn about shadowing, but only in source modules
- ifOptM Opt_WarnNameShadowing
- (checkShadowing doc_str rdr_names_w_loc) `thenM_`
+bindLocatedLocalsRn rdr_names_w_loc enclosed_scope
+ = do { checkDupAndShadowedRdrNames rdr_names_w_loc
-- Make fresh Names and extend the environment
- newLocalsRn rdr_names_w_loc `thenM` \ names ->
- getLocalRdrEnv `thenM` \ local_env ->
- setLocalRdrEnv (extendLocalRdrEnv local_env names)
- (enclosed_scope names)
-
+ ; names <- newLocalBndrsRn rdr_names_w_loc
+ ; bindLocalNames names (enclosed_scope names) }
bindLocalNames :: [Name] -> RnM a -> RnM a
bindLocalNames names enclosed_scope
- = getLocalRdrEnv `thenM` \ name_env ->
- setLocalRdrEnv (extendLocalRdrEnv name_env names)
- enclosed_scope
+ = do { name_env <- getLocalRdrEnv
+ ; setLocalRdrEnv (extendLocalRdrEnvList name_env names)
+ enclosed_scope }
+
+bindLocalName :: Name -> RnM a -> RnM a
+bindLocalName name enclosed_scope
+ = do { name_env <- getLocalRdrEnv
+ ; setLocalRdrEnv (extendLocalRdrEnv name_env name)
+ enclosed_scope }
bindLocalNamesFV :: [Name] -> RnM (a, FreeVars) -> RnM (a, FreeVars)
bindLocalNamesFV names enclosed_scope
= do { (result, fvs) <- bindLocalNames names enclosed_scope
- ; returnM (result, delListFromNameSet fvs names) }
+ ; return (result, delFVs names fvs) }
-------------------------------------
-- binLocalsFVRn is the same as bindLocalsRn
-- except that it deals with free vars
-bindLocatedLocalsFV :: SDoc -> [Located RdrName] -> ([Name] -> RnM (a,FreeVars))
- -> RnM (a, FreeVars)
-bindLocatedLocalsFV doc rdr_names enclosed_scope
- = bindLocatedLocalsRn doc rdr_names $ \ names ->
+bindLocatedLocalsFV :: [Located RdrName]
+ -> ([Name] -> RnM (a,FreeVars)) -> RnM (a, FreeVars)
+bindLocatedLocalsFV rdr_names enclosed_scope
+ = bindLocatedLocalsRn rdr_names $ \ names ->
enclosed_scope names `thenM` \ (thing, fvs) ->
- returnM (thing, delListFromNameSet fvs names)
+ return (thing, delFVs names fvs)
-------------------------------------
-bindTyVarsRn :: SDoc -> [LHsTyVarBndr RdrName]
+bindTyVarsFV :: [LHsTyVarBndr RdrName]
+ -> ([LHsTyVarBndr Name] -> RnM (a, FreeVars))
+ -> RnM (a, FreeVars)
+bindTyVarsFV tyvars thing_inside
+ = bindTyVarsRn tyvars $ \ tyvars' ->
+ do { (res, fvs) <- thing_inside tyvars'
+ ; return (res, delFVs (map hsLTyVarName tyvars') fvs) }
+
+bindTyVarsRn :: [LHsTyVarBndr RdrName]
-> ([LHsTyVarBndr Name] -> RnM a)
-> 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)
+bindTyVarsRn tyvar_names enclosed_scope
+ = bindLocatedLocalsRn located_tyvars $ \ names ->
+ do { kind_sigs_ok <- xoptM Opt_KindSignatures
+ ; unless (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
-- signatures that must be brought into scope
bindPatSigTyVars tys thing_inside
- = do { scoped_tyvars <- doptM Opt_ScopedTypeVariables
+ = do { scoped_tyvars <- xoptM Opt_ScopedTypeVariables
; if not scoped_tyvars then
thing_inside []
else
-- f (x :: t) (y :: t) = ....
-- We don't want to complain about binding t twice!
- ; bindLocatedLocalsRn doc_sig nubbed_tvs thing_inside }}
- where
- doc_sig = text "In a pattern type-signature"
+ ; bindLocatedLocalsRn nubbed_tvs thing_inside }}
bindPatSigTyVarsFV :: [LHsType RdrName]
-> RnM (a, FreeVars)
bindPatSigTyVarsFV tys thing_inside
= bindPatSigTyVars tys $ \ tvs ->
thing_inside `thenM` \ (result,fvs) ->
- returnM (result, fvs `delListFromNameSet` tvs)
+ return (result, fvs `delListFromNameSet` tvs)
bindSigTyVarsFV :: [Name]
-> RnM (a, FreeVars)
-> RnM (a, FreeVars)
bindSigTyVarsFV tvs thing_inside
- = do { scoped_tyvars <- doptM Opt_ScopedTypeVariables
+ = do { scoped_tyvars <- xoptM Opt_ScopedTypeVariables
; if not scoped_tyvars then
thing_inside
else
extendTyVarEnvFVRn tyvars thing_inside = bindLocalNamesFV tyvars thing_inside
-------------------------------------
-checkDupNames :: SDoc
- -> [Located RdrName]
- -> RnM ()
-checkDupNames doc_str rdr_names_w_loc
+checkDupRdrNames :: [Located RdrName] -> RnM ()
+checkDupRdrNames rdr_names_w_loc
= -- Check for duplicated names in a binding group
- mappM_ (dupNamesErr doc_str) dups
+ mapM_ (dupNamesErr getLoc) dups
where
(_, dups) = removeDups (\n1 n2 -> unLoc n1 `compare` unLoc n2) rdr_names_w_loc
+checkDupNames :: [Name] -> RnM ()
+checkDupNames names
+ = -- Check for duplicated names in a binding group
+ mapM_ (dupNamesErr nameSrcSpan) dups
+ where
+ (_, dups) = removeDups (\n1 n2 -> nameOccName n1 `compare` nameOccName n2) names
+
+---------------------
+checkDupAndShadowedRdrNames :: [Located RdrName] -> RnM ()
+checkDupAndShadowedRdrNames loc_rdr_names
+ = do { checkDupRdrNames loc_rdr_names
+ ; envs <- getRdrEnvs
+ ; checkShadowedOccs envs loc_occs }
+ where
+ loc_occs = [(loc,rdrNameOcc rdr) | L loc rdr <- loc_rdr_names]
+
+checkDupAndShadowedNames :: (GlobalRdrEnv, LocalRdrEnv) -> [Name] -> RnM ()
+checkDupAndShadowedNames envs names
+ = do { checkDupNames names
+ ; checkShadowedOccs envs loc_occs }
+ where
+ loc_occs = [(nameSrcSpan name, nameOccName name) | name <- names]
+
-------------------------------------
-checkShadowing doc_str loc_rdr_names
- = getLocalRdrEnv `thenM` \ local_env ->
- getGlobalRdrEnv `thenM` \ global_env ->
- let
- check_shadow (L loc rdr_name)
- | rdr_name `elemLocalRdrEnv` local_env
- || not (null (lookupGRE_RdrName rdr_name global_env ))
- = addWarnAt loc (shadowedNameWarn doc_str rdr_name)
- | otherwise = returnM ()
- in
- mappM_ check_shadow loc_rdr_names
+checkShadowedOccs :: (GlobalRdrEnv, LocalRdrEnv) -> [(SrcSpan,OccName)] -> RnM ()
+checkShadowedOccs (global_env,local_env) loc_occs
+ = ifDOptM Opt_WarnNameShadowing $
+ do { traceRn (text "shadow" <+> ppr loc_occs)
+ ; mapM_ check_shadow loc_occs }
+ where
+ check_shadow (loc, occ)
+ | 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 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 (xopt Opt_RecordPuns dflags || xopt 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}
%************************************************************************
%* *
+ What to do when a lookup fails
+%* *
+%************************************************************************
+
+\begin{code}
+data WhereLooking = WL_Any -- Any binding
+ | WL_Global -- Any top-level binding (local or imported)
+ | WL_LocalTop -- Any top-level binding in this module
+
+unboundName :: WhereLooking -> RdrName -> RnM Name
+unboundName where_look rdr_name
+ = do { show_helpful_errors <- doptM Opt_HelpfulErrors
+ ; let err = unknownNameErr rdr_name
+ ; if not show_helpful_errors
+ then addErr err
+ else do { extra_err <- unknownNameSuggestErr where_look rdr_name
+ ; addErr (err $$ extra_err) }
+
+ ; env <- getGlobalRdrEnv;
+ ; traceRn (vcat [unknownNameErr rdr_name,
+ ptext (sLit "Global envt is:"),
+ nest 3 (pprGlobalRdrEnv env)])
+
+ ; return (mkUnboundName rdr_name) }
+
+unknownNameErr :: RdrName -> SDoc
+unknownNameErr 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
+
+type HowInScope = Either SrcSpan ImpDeclSpec
+ -- Left loc => locally bound at loc
+ -- Right ispec => imported as specified by ispec
+
+unknownNameSuggestErr :: WhereLooking -> RdrName -> RnM SDoc
+unknownNameSuggestErr where_look tried_rdr_name
+ = do { local_env <- getLocalRdrEnv
+ ; global_env <- getGlobalRdrEnv
+
+ ; let all_possibilities :: [(String, (RdrName, HowInScope))]
+ all_possibilities
+ = [ (showSDoc (ppr r), (r, Left loc))
+ | (r,loc) <- local_possibilities local_env ]
+ ++ [ (showSDoc (ppr r), rp) | (r,rp) <- global_possibilities global_env ]
+
+ suggest = fuzzyLookup (showSDoc (ppr tried_rdr_name)) all_possibilities
+ perhaps = ptext (sLit "Perhaps you meant")
+ extra_err = case suggest of
+ [] -> empty
+ [p] -> perhaps <+> pp_item p
+ ps -> sep [ perhaps <+> ptext (sLit "one of these:")
+ , nest 2 (pprWithCommas pp_item ps) ]
+ ; return extra_err }
+ where
+ pp_item :: (RdrName, HowInScope) -> SDoc
+ pp_item (rdr, Left loc) = quotes (ppr rdr) <+> -- Locally defined
+ parens (ptext (sLit "line") <+> int (srcSpanStartLine loc))
+ pp_item (rdr, Right is) = quotes (ppr rdr) <+> -- Imported
+ parens (ptext (sLit "imported from") <+> ppr (is_mod is))
+
+ tried_occ = rdrNameOcc tried_rdr_name
+ tried_is_sym = isSymOcc tried_occ
+ tried_ns = occNameSpace tried_occ
+ tried_is_qual = isQual tried_rdr_name
+
+ correct_name_space occ = occNameSpace occ == tried_ns
+ && isSymOcc occ == tried_is_sym
+ -- Treat operator and non-operators as non-matching
+ -- This heuristic avoids things like
+ -- Not in scope 'f'; perhaps you meant '+' (from Prelude)
+
+ local_ok = case where_look of { WL_Any -> True; _ -> False }
+ local_possibilities :: LocalRdrEnv -> [(RdrName, SrcSpan)]
+ local_possibilities env
+ | tried_is_qual = []
+ | not local_ok = []
+ | otherwise = [ (mkRdrUnqual occ, nameSrcSpan name)
+ | name <- occEnvElts env
+ , let occ = nameOccName name
+ , correct_name_space occ]
+
+ gre_ok :: GlobalRdrElt -> Bool
+ gre_ok = case where_look of
+ WL_LocalTop -> isLocalGRE
+ _ -> \_ -> True
+
+ global_possibilities :: GlobalRdrEnv -> [(RdrName, (RdrName, HowInScope))]
+ global_possibilities global_env
+ | tried_is_qual = [ (rdr_qual, (rdr_qual, how))
+ | gre <- globalRdrEnvElts global_env
+ , gre_ok gre
+ , let name = gre_name gre
+ occ = nameOccName name
+ , correct_name_space occ
+ , (mod, how) <- quals_in_scope name (gre_prov gre)
+ , let rdr_qual = mkRdrQual mod occ ]
+
+ | otherwise = [ (rdr_unqual, pair)
+ | gre <- globalRdrEnvElts global_env
+ , gre_ok gre
+ , let name = gre_name gre
+ prov = gre_prov gre
+ occ = nameOccName name
+ rdr_unqual = mkRdrUnqual occ
+ , correct_name_space occ
+ , pair <- case (unquals_in_scope name prov, quals_only occ prov) of
+ (how:_, _) -> [ (rdr_unqual, how) ]
+ ([], pr:_) -> [ pr ] -- See Note [Only-quals]
+ ([], []) -> [] ]
+
+ -- Note [Only-quals]
+ -- The second alternative returns those names with the same
+ -- OccName as the one we tried, but live in *qualified* imports
+ -- e.g. if you have:
+ --
+ -- > import qualified Data.Map as Map
+ -- > foo :: Map
+ --
+ -- then we suggest @Map.Map@.
+
+ --------------------
+ unquals_in_scope :: Name -> Provenance -> [HowInScope]
+ unquals_in_scope n LocalDef = [ Left (nameSrcSpan n) ]
+ unquals_in_scope _ (Imported is) = [ Right ispec
+ | i <- is, let ispec = is_decl i
+ , not (is_qual ispec) ]
+
+ --------------------
+ quals_in_scope :: Name -> Provenance -> [(ModuleName, HowInScope)]
+ -- Ones for which the qualified version is in scope
+ quals_in_scope n LocalDef = case nameModule_maybe n of
+ Nothing -> []
+ Just m -> [(moduleName m, Left (nameSrcSpan n))]
+ quals_in_scope _ (Imported is) = [ (is_as ispec, Right ispec)
+ | i <- is, let ispec = is_decl i ]
+
+ --------------------
+ quals_only :: OccName -> Provenance -> [(RdrName, HowInScope)]
+ -- Ones for which *only* the qualified version is in scope
+ quals_only _ LocalDef = []
+ quals_only occ (Imported is) = [ (mkRdrQual (is_as ispec) occ, Right ispec)
+ | i <- is, let ispec = is_decl i, is_qual ispec ]
+\end{code}
+
+%************************************************************************
+%* *
\subsection{Free variable manipulation}
%* *
%************************************************************************
\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)
+addFvRn :: FreeVars -> RnM (thing, FreeVars) -> RnM (thing, FreeVars)
+addFvRn fvs1 thing_inside = do { (res, fvs2) <- thing_inside
+ ; return (res, fvs1 `plusFV` fvs2) }
+
+mapFvRn :: (a -> RnM (b, FreeVars)) -> [a] -> RnM ([b], FreeVars)
+mapFvRn f xs = do stuff <- mapM f xs
+ case unzip stuff of
+ (ys, fvs_s) -> return (ys, plusFVs fvs_s)
+
+mapMaybeFvRn :: (a -> RnM (b, FreeVars)) -> Maybe a -> RnM (Maybe b, FreeVars)
+mapMaybeFvRn _ Nothing = return (Nothing, emptyFVs)
+mapMaybeFvRn f (Just x) = do { (y, fvs) <- f x; return (Just y, fvs) }
+
+-- because some of the rename functions are CPSed:
+-- maps the function across the list from left to right;
+-- collects all the free vars into one set
+mapFvRnCPS :: (a -> (b -> RnM c) -> RnM c)
+ -> [a] -> ([b] -> RnM c) -> RnM c
+
+mapFvRnCPS _ [] cont = cont []
+mapFvRnCPS f (x:xs) cont = f x $ \ x' ->
+ mapFvRnCPS f xs $ \ xs' ->
+ cont (x':xs')
\end{code}
%************************************************************************
\begin{code}
-warnUnusedModules :: [(ModuleName,SrcSpan)] -> RnM ()
-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)
- <+> text "is imported, but nothing from it is used,",
- 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 ]
-
-
-warnUnusedImports, warnUnusedTopBinds :: [GlobalRdrElt] -> RnM ()
-warnUnusedImports gres = ifOptM Opt_WarnUnusedImports (warnUnusedGREs gres)
-warnUnusedTopBinds gres = ifOptM Opt_WarnUnusedBinds (warnUnusedGREs gres)
-
-warnUnusedLocalBinds, warnUnusedMatches :: [Name] -> RnM ()
-warnUnusedLocalBinds names = ifOptM Opt_WarnUnusedBinds (warnUnusedLocals names)
-warnUnusedMatches names = ifOptM Opt_WarnUnusedMatches (warnUnusedLocals names)
+warnUnusedTopBinds :: [GlobalRdrElt] -> RnM ()
+warnUnusedTopBinds gres
+ = ifDOptM Opt_WarnUnusedBinds
+ $ do isBoot <- tcIsHsBoot
+ let noParent gre = case gre_par gre of
+ NoParent -> True
+ ParentIs _ -> False
+ -- Don't warn about unused bindings with parents in
+ -- .hs-boot files, as you are sometimes required to give
+ -- unused bindings (trac #3449).
+ gres' = if isBoot then filter noParent gres
+ else gres
+ warnUnusedGREs gres'
+
+warnUnusedLocalBinds, warnUnusedMatches :: [Name] -> FreeVars -> RnM ()
+warnUnusedLocalBinds = check_unused Opt_WarnUnusedBinds
+warnUnusedMatches = check_unused Opt_WarnUnusedMatches
+
+check_unused :: DynFlag -> [Name] -> FreeVars -> RnM ()
+check_unused flag bound_names used_names
+ = ifDOptM 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]
warnUnusedBinds :: [(Name,Provenance)] -> RnM ()
-warnUnusedBinds names = mappM_ warnUnusedName (filter reportable names)
+warnUnusedBinds names = mapM_ warnUnusedName (filter reportable names)
where reportable (name,_)
| 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
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,
\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]
- mk_ref gre = quotes (ppr (gre_name gre)) <> comma <+> pprNameProvenance gre
-
-shadowedNameWarn doc shadow
- = hsep [ptext SLIT("This binding for"),
- quotes (ppr shadow),
- ptext SLIT("shadows an existing binding")]
- $$ doc
-
-unknownNameErr rdr_name
- = sep [ptext SLIT("Not in scope:"),
- 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)
-
+ msg1 = ptext (sLit "either") <+> mk_ref np1
+ msgs = [ptext (sLit " or") <+> mk_ref np | np <- nps]
+ mk_ref gre = sep [quotes (ppr (gre_name gre)) <> comma, pprNameProvenance gre]
+
+shadowedNameWarn :: OccName -> [SDoc] -> SDoc
+shadowedNameWarn occ 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)]
+
+perhapsForallMsg :: SDoc
+perhapsForallMsg
+ = vcat [ ptext (sLit "Perhaps you intended to use -XExplicitForAll or similar flag")
+ , ptext (sLit "to enable explicit-forall syntax: forall <tvs>. <type>")]
+
+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
+
+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 :: SDoc -> [Located RdrName] -> RnM ()
-dupNamesErr descriptor located_names
+dupNamesErr :: Outputable n => (n -> SrcSpan) -> [n] -> RnM ()
+dupNamesErr get_loc names
= addErrAt big_loc $
- vcat [ptext SLIT("Conflicting definitions for") <+> quotes (ppr name1),
- locations, descriptor]
+ vcat [ptext (sLit "Conflicting definitions for") <+> quotes (ppr (head names)),
+ locations]
where
- L _ name1 = head located_names
- locs = map getLoc located_names
+ locs = map get_loc names
big_loc = foldr1 combineSrcSpans locs
- one_line = isOneLineSpan big_loc
- locations | one_line = empty
- | otherwise = ptext SLIT("Bound at:") <+>
- vcat (map ppr (sortLe (<=) locs))
+ locations = 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
-infixTyConWarn op
- = vcat [ftext FSLIT("Accepting non-standard infix type constructor") <+> quotes (ppr op),
- ftext FSLIT("Use -fglasgow-exts to avoid this warning")]
+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}
projects / ghc-hetmet.git / blobdiff