\section[RnEnv]{Environment manipulation for the renamer monad}
\begin{code}
-module RnEnv where -- Export everything
+module RnEnv (
+ newTopSrcBinder,
+ lookupLocatedBndrRn, lookupBndrRn,
+ lookupLocatedTopBndrRn, lookupTopBndrRn,
+ lookupLocatedOccRn, lookupOccRn,
+ lookupLocatedGlobalOccRn, lookupGlobalOccRn,
+ lookupTopFixSigNames, lookupSrcOcc_maybe,
+ lookupFixityRn, lookupLocatedSigOccRn,
+ lookupLocatedInstDeclBndr,
+ lookupSyntaxName, lookupSyntaxNames, lookupImportedName,
+
+ newLocalsRn, newIPNameRn,
+ bindLocalNames, bindLocalNamesFV,
+ bindLocatedLocalsFV, bindLocatedLocalsRn,
+ bindPatSigTyVars, bindPatSigTyVarsFV,
+ bindTyVarsRn, extendTyVarEnvFVRn,
+ bindLocalFixities,
+
+ checkDupNames, mapFvRn,
+ warnUnusedMatches, warnUnusedModules, warnUnusedImports,
+ warnUnusedTopBinds, warnUnusedLocalBinds,
+ dataTcOccs, unknownNameErr,
+ ) where
#include "HsVersions.h"
-import CmdLineOpts ( opt_WarnNameShadowing, opt_WarnUnusedMatches,
- opt_WarnUnusedBinds, opt_WarnUnusedImports )
+import LoadIface ( loadSrcInterface )
+import IfaceEnv ( lookupOrig, newGlobalBinder, newIPName )
import HsSyn
-import RdrHsSyn ( RdrNameIE )
-import RnHsSyn ( RenamedHsType )
-import RdrName ( RdrName, rdrNameModule, rdrNameOcc, isQual, isUnqual,
- mkRdrUnqual, qualifyRdrName
- )
-import HsTypes ( getTyVarName, replaceTyVarName )
-
-import RnMonad
-import Name ( Name, Provenance(..), ExportFlag(..), NamedThing(..),
- ImportReason(..), getSrcLoc,
- mkLocalName, mkImportedLocalName, mkGlobalName, mkUnboundName,
- mkIPName, isSystemName, isWiredInName,
- nameOccName, setNameModule, nameModule,
- pprOccName, isLocallyDefined, nameUnique, nameOccName,
- occNameUserString,
- setNameProvenance, getNameProvenance, pprNameProvenance
+import RdrHsSyn ( extractHsTyRdrTyVars )
+import RdrName ( RdrName, rdrNameModule, rdrNameOcc, isQual, isUnqual, isOrig,
+ mkRdrUnqual, setRdrNameSpace, rdrNameOcc,
+ pprGlobalRdrEnv, lookupGRE_RdrName,
+ isExact_maybe, isSrcRdrName,
+ GlobalRdrElt(..), GlobalRdrEnv, lookupGlobalRdrEnv,
+ isLocalGRE, extendLocalRdrEnv, elemLocalRdrEnv, lookupLocalRdrEnv,
+ Provenance(..), pprNameProvenance, ImportSpec(..)
)
+import HsTypes ( hsTyVarName, replaceTyVarName )
+import HscTypes ( availNames, ModIface(..), FixItem(..), lookupFixity )
+import TcRnMonad
+import Name ( Name, nameIsLocalOrFrom, mkInternalName, isInternalName,
+ nameSrcLoc, nameOccName, nameModuleName, nameParent )
import NameSet
-import OccName ( OccName,
- mkDFunOcc, occNameUserString, occNameString,
- occNameFlavour
- )
-import TysWiredIn ( tupleTyCon, unboxedTupleTyCon, listTyCon )
-import Type ( funTyCon )
-import Module ( ModuleName, mkThisModule, moduleName, mkVanillaModule, pprModuleName )
-import TyCon ( TyCon )
-import FiniteMap
-import Unique ( Unique, Uniquable(..) )
+import OccName ( tcName, isDataOcc, occNameFlavour, reportIfUnused,
+ isVarOcc )
+import Module ( Module, ModuleName, moduleName, mkHomeModule )
+import PrelNames ( mkUnboundName, rOOT_MAIN_Name, iNTERACTIVE )
import UniqSupply
-import SrcLoc ( SrcLoc, noSrcLoc )
+import BasicTypes ( IPName, mapIPName )
+import SrcLoc ( srcSpanStart, Located(..), eqLocated, unLoc,
+ srcLocSpan )
import Outputable
-import Util ( removeDups, equivClasses, thenCmp )
-import List ( nub )
+import ListSetOps ( removeDups )
+import List ( nubBy )
+import CmdLineOpts
+import FastString ( FastString )
\end{code}
-
-
%*********************************************************
%* *
-\subsection{Making new names}
+ Source-code binders
%* *
%*********************************************************
\begin{code}
-newLocalTopBinder :: Module -> OccName
- -> (Name -> ExportFlag) -> SrcLoc
- -> RnM d Name
-newLocalTopBinder mod occ rec_exp_fn loc
- = newTopBinder mod occ (\name -> setNameProvenance name (LocalDef loc (rec_exp_fn name)))
- -- We must set the provenance of the thing in the cache
- -- correctly, particularly whether or not it is locally defined.
- --
- -- Since newLocalTopBinder is used only
- -- at binding occurrences, we may as well get the provenance
- -- dead right first time; hence the rec_exp_fn passed in
-
-newImportedBinder :: Module -> RdrName -> RnM d Name
-newImportedBinder mod rdr_name
- = ASSERT2( isUnqual rdr_name, ppr rdr_name )
- newTopBinder mod (rdrNameOcc rdr_name) (\name -> name)
- -- Provenance is already implicitImportProvenance
-
-implicitImportProvenance = NonLocalDef ImplicitImport False
-
-newTopBinder :: Module -> OccName -> (Name -> Name) -> RnM d Name
-newTopBinder mod occ set_prov
- = -- First check the cache
- getNameSupplyRn `thenRn` \ (us, inst_ns, cache, ipcache) ->
- let
- key = (moduleName mod, occ)
- in
- case lookupFM cache key of
-
- -- A hit in the cache!
- -- Set the Module of the thing, and set its provenance (hack pending
- -- spj update)
+newTopSrcBinder :: Module -> Maybe Name -> Located RdrName -> RnM Name
+newTopSrcBinder mod mb_parent (L loc rdr_name)
+ | Just name <- isExact_maybe rdr_name
+ = returnM name
+
+ | isOrig rdr_name
+ = ASSERT( rdr_mod == moduleName mod || rdr_mod == rOOT_MAIN_Name )
+ -- When reading External Core we get Orig names as binders,
+ -- but they should agree with the module gotten from the monad
--
- -- It also means that if there are two defns for the same thing
- -- in a module, then each gets a separate SrcLoc
+ -- Except for the ":Main.main = ..." definition inserted into
+ -- the Main module
--
- -- There's a complication for wired-in names. We don't want to
- -- forget that they are wired in even when compiling that module
- -- (else we spit out redundant defns into the interface file)
- -- So for them we just set the provenance
-
- Just name -> let
- new_name = set_prov (setNameModule name mod)
- new_cache = addToFM cache key new_name
- in
- setNameSupplyRn (us, inst_ns, new_cache, ipcache) `thenRn_`
- returnRn new_name
-
- -- Miss in the cache!
- -- Build a completely new Name, and put it in the cache
- Nothing -> let
- (us', us1) = splitUniqSupply us
- uniq = uniqFromSupply us1
- new_name = set_prov (mkGlobalName uniq mod occ implicitImportProvenance)
- new_cache = addToFM cache key new_name
- in
- setNameSupplyRn (us', inst_ns, new_cache, ipcache) `thenRn_`
- returnRn new_name
-
-
-mkImportedGlobalName :: ModuleName -> OccName -> RnM d Name
- -- Used for *occurrences*. We make a place-holder Name, really just
- -- to agree on its unique, which gets overwritten when we read in
- -- the binding occurence later (newImportedBinder)
- -- The place-holder Name doesn't have the right Provenance, and its
- -- Module won't have the right Package either
- --
- -- This means that a renamed program may have incorrect info
- -- on implicitly-imported occurrences, but the correct info on the
- -- *binding* declaration. It's the type checker that propagates the
- -- correct information to all the occurrences.
- -- Since implicitly-imported names never occur in error messages,
- -- it doesn't matter that we get the correct info in place till later,
- -- (but since it affects DLL-ery it does matter that we get it right
- -- in the end).
-mkImportedGlobalName mod_name occ
- = getNameSupplyRn `thenRn` \ (us, inst_ns, cache, ipcache) ->
- let
- key = (mod_name, occ)
- in
- case lookupFM cache key of
- Just name -> returnRn name
- Nothing -> setNameSupplyRn (us', inst_ns, new_cache, ipcache) `thenRn_`
- returnRn name
- where
- (us', us1) = splitUniqSupply us
- uniq = uniqFromSupply us1
- mod = mkVanillaModule mod_name
- name = mkGlobalName uniq mod occ implicitImportProvenance
- new_cache = addToFM cache key name
-
-updateProvenances :: [Name] -> RnM d ()
--- Update the provenances of everything that is in scope.
--- We must be careful not to disturb the Module package info
--- already in the cache. Why not? Consider
--- module A module M( f )
--- import M( f ) import N( f)
--- import N
--- So f is defined in N, and M re-exports it.
--- When processing module A:
--- 1. We read M.hi first, and make a vanilla name N.f
--- (without reading N.hi). The package info says <THIS>
--- for lack of anything better.
--- 2. Now we read N, which update the cache to record
--- the correct package for N.f.
--- 3. Finally we update provenances (once we've read all imports).
--- Step 3 must not destroy package info recorded in Step 2.
-
-updateProvenances names
- = getNameSupplyRn `thenRn` \ (us, inst_ns, cache, ipcache) ->
- setNameSupplyRn (us, inst_ns, foldr update cache names, ipcache)
- where
- update name cache = addToFM_C update_prov cache key name
- where
- key = (moduleName (nameModule name), nameOccName name)
-
- update_prov name_in_cache name_with_prov
- = setNameProvenance name_in_cache (getNameProvenance name_with_prov)
-
-
-
-mkImportedGlobalFromRdrName :: RdrName -> RnM d Name
-mkImportedGlobalFromRdrName rdr_name
- | isQual rdr_name
- = mkImportedGlobalName (rdrNameModule rdr_name) (rdrNameOcc rdr_name)
+ -- Because of this latter case, we take the module from 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 (mkHomeModule rdr_mod) (rdrNameOcc rdr_name) mb_parent
+ (srcSpanStart loc) --TODO, should pass the whole span
| otherwise
- = -- An Unqual is allowed; interface files contain
- -- unqualified names for locally-defined things, such as
- -- constructors of a data type.
- getModuleRn `thenRn ` \ mod_name ->
- mkImportedGlobalName mod_name (rdrNameOcc rdr_name)
-
-
-getIPName rdr_name
- = getNameSupplyRn `thenRn` \ (us, inst_ns, cache, ipcache) ->
- case lookupFM ipcache key of
- Just name -> returnRn name
- Nothing -> setNameSupplyRn (us', inst_ns, cache, new_ipcache) `thenRn_`
- returnRn name
- where
- (us', us1) = splitUniqSupply us
- uniq = uniqFromSupply us1
- name = mkIPName uniq key
- new_ipcache = addToFM ipcache key name
- where key = (rdrNameOcc rdr_name)
+ = newGlobalBinder mod (rdrNameOcc rdr_name) mb_parent (srcSpanStart loc)
+ where
+ rdr_mod = rdrNameModule rdr_name
\end{code}
%*********************************************************
%* *
-\subsection{Dfuns and default methods}
+ Source code occurrences
%* *
%*********************************************************
-@newImplicitBinder@ is used for (a) dfuns
-(b) default methods, defined in this module.
+Looking up a name in the RnEnv.
\begin{code}
-newImplicitBinder occ src_loc
- = getModuleRn `thenRn` \ mod_name ->
- newLocalTopBinder (mkThisModule mod_name) occ (\_ -> Exported) src_loc
-\end{code}
+lookupLocatedBndrRn :: Located RdrName -> RnM (Located Name)
+lookupLocatedBndrRn = wrapLocM lookupBndrRn
-Make a name for the dict fun for an instance decl
+lookupBndrRn :: RdrName -> RnM Name
+-- NOTE: assumes that the SrcSpan of the binder has already been addSrcSpan'd
+lookupBndrRn rdr_name
+ = getLocalRdrEnv `thenM` \ local_env ->
+ case lookupLocalRdrEnv local_env rdr_name of
+ Just name -> returnM name
+ Nothing -> lookupTopBndrRn rdr_name
+
+lookupLocatedTopBndrRn :: Located RdrName -> RnM (Located Name)
+lookupLocatedTopBndrRn = wrapLocM lookupTopBndrRn
+
+lookupTopBndrRn :: RdrName -> RnM 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:
+-- import Foo( f )
+-- infix 9 f -- The 'f' here does not need to be qualified
+-- f x = x -- Nor here, of course
+-- So we have to filter out the non-local ones.
+--
+-- A separate function (importsFromLocalDecls) reports duplicate top level
+-- decls, so here it's safe just to choose an arbitrary one.
+--
+-- There should never be a qualified name in a binding position in Haskell,
+-- but there can be if we have read in an external-Core file.
+-- 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
+ | Just name <- isExact_maybe rdr_name
+ -- This is here to catch
+ -- (a) Exact-name binders created by Template Haskell
+ -- (b) The PrelBase defn of (say) [] and similar, for which
+ -- the parser reads the special syntax and returns an Exact RdrName
+ --
+ -- We are at a binding site for the name, so check first that it
+ -- the current module is the correct one; otherwise GHC can get
+ -- very confused indeed. This test rejects code like
+ -- data T = (,) Int Int
+ -- unless we are in GHC.Tup
+ = getModule `thenM` \ mod ->
+ checkErr (isInternalName name || moduleName mod == nameModuleName name)
+ (badOrigBinding rdr_name) `thenM_`
+ returnM name
+
+ | isOrig 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 (mkHomeModule (rdrNameModule rdr_name))
+ (rdrNameOcc rdr_name) Nothing (srcSpanStart loc)
-\begin{code}
-newDFunName :: (OccName, OccName) -> SrcLoc -> RnMS Name
-newDFunName key@(cl_occ, tycon_occ) loc
- = newInstUniq string `thenRn` \ inst_uniq ->
- newImplicitBinder (mkDFunOcc string inst_uniq) loc
- where
- -- Any string that is somewhat unique will do
- string = occNameString cl_occ ++ occNameString tycon_occ
-\end{code}
+ | otherwise
+ = do { mb_gre <- lookupGreLocalRn rdr_name
+ ; case mb_gre of
+ Nothing -> unboundName rdr_name
+ Just gre -> returnM (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 = wrapLocM (lookupInstDeclBndr cls)
+
+lookupInstDeclBndr :: Name -> RdrName -> RnM Name
+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 = cls_name == nameParent (gre_name gre)
+ ; occ = rdrNameOcc rdr_name
+ ; lookup_fn env = filter is_op (lookupGlobalRdrEnv env occ) }
+ ; mb_gre <- lookupGreRn_help rdr_name lookup_fn
+ ; case mb_gre of
+ Just gre -> return (gre_name gre)
+ Nothing -> do { addErr (unknownInstBndrErr cls_name rdr_name)
+ ; return (mkUnboundName rdr_name) } }
+
+ | 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
+
+newIPNameRn :: IPName RdrName -> TcRnIf m n (IPName Name)
+newIPNameRn ip_rdr = newIPName (mapIPName rdrNameOcc ip_rdr)
+
+--------------------------------------------------
+-- Occurrences
+--------------------------------------------------
+
+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
-\begin{code}
-getDFunKey :: RenamedHsType -> (OccName, OccName) -- Used to manufacture DFun names
-getDFunKey (HsForAllTy _ _ ty) = getDFunKey ty
-getDFunKey (MonoFunTy _ ty) = getDFunKey ty
-getDFunKey (MonoDictTy cls (ty:_)) = (nameOccName cls, get_tycon_key ty)
-
-get_tycon_key (MonoTyVar tv) = nameOccName (getName tv)
-get_tycon_key (MonoTyApp ty _) = get_tycon_key ty
-get_tycon_key (MonoTupleTy tys True) = getOccName (tupleTyCon (length tys))
-get_tycon_key (MonoTupleTy tys False) = getOccName (unboxedTupleTyCon (length tys))
-get_tycon_key (MonoListTy _) = getOccName listTyCon
-get_tycon_key (MonoFunTy _ _) = getOccName funTyCon
-\end{code}
+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
-%*********************************************************
-%* *
-\subsection{Binding}
-%* *
-%*********************************************************
+lookupGlobalOccRn rdr_name
+ | not (isSrcRdrName rdr_name)
+ = lookupImportedName rdr_name
-\begin{code}
--------------------------------------
-bindLocatedLocalsRn :: SDoc -- Documentation string for error message
- -> [(RdrName,SrcLoc)]
- -> ([Name] -> RnMS a)
- -> RnMS a
-bindLocatedLocalsRn doc_str rdr_names_w_loc enclosed_scope
- = checkDupOrQualNames doc_str rdr_names_w_loc `thenRn_`
-
- getLocalNameEnv `thenRn` \ name_env ->
- (if opt_WarnNameShadowing
- then
- mapRn_ (check_shadow name_env) rdr_names_w_loc
- else
- returnRn ()
- ) `thenRn_`
+ | otherwise
+ = -- First look up the name in the normal environment.
+ lookupGreRn rdr_name `thenM` \ mb_gre ->
+ case mb_gre of {
+ Just gre -> returnM (gre_name gre) ;
+ Nothing ->
+
+ -- 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
+ 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
+
+ | otherwise -- Always Orig, even when reading a .hi-boot file
+ = ASSERT( not (isUnqual rdr_name) )
+ lookupOrig (rdrNameModule rdr_name) (rdrNameOcc rdr_name)
+
+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 rdr_name
+ ; case mb_gre of
+ Nothing -> returnM Nothing
+ Just gre -> returnM (Just (gre_name gre)) }
- getNameSupplyRn `thenRn` \ (us, inst_ns, cache, ipcache) ->
- getModeRn `thenRn` \ mode ->
- let
- n = length rdr_names_w_loc
- (us', us1) = splitUniqSupply us
- uniqs = uniqsFromSupply n us1
- names = [ mk_name uniq (rdrNameOcc rdr_name) loc
- | ((rdr_name,loc), uniq) <- rdr_names_w_loc `zip` uniqs
- ]
- mk_name = case mode of
- SourceMode -> mkLocalName
- InterfaceMode -> mkImportedLocalName
- -- Keep track of whether the name originally came from
- -- an interface file.
- in
- setNameSupplyRn (us', inst_ns, cache, ipcache) `thenRn_`
-
- let
- new_name_env = addListToRdrEnv name_env (map fst rdr_names_w_loc `zip` names)
- in
- setLocalNameEnv new_name_env (enclosed_scope names)
-
- where
- check_shadow name_env (rdr_name,loc)
- = case lookupRdrEnv name_env rdr_name of
- Nothing -> returnRn ()
- Just name -> pushSrcLocRn loc $
- addWarnRn (shadowedNameWarn rdr_name)
-
-bindCoreLocalFVRn :: RdrName -> (Name -> RnMS (a, FreeVars))
- -> RnMS (a, FreeVars)
- -- A specialised variant when renaming stuff from interface
- -- files (of which there is a lot)
- -- * one at a time
- -- * no checks for shadowing
- -- * always imported
- -- * deal with free vars
-bindCoreLocalFVRn rdr_name enclosed_scope
- = getSrcLocRn `thenRn` \ loc ->
- getLocalNameEnv `thenRn` \ name_env ->
- getNameSupplyRn `thenRn` \ (us, inst_ns, cache, ipcache) ->
- let
- (us', us1) = splitUniqSupply us
- uniq = uniqFromSupply us1
- name = mkImportedLocalName uniq (rdrNameOcc rdr_name) loc
- in
- setNameSupplyRn (us', inst_ns, cache, ipcache) `thenRn_`
- let
- new_name_env = extendRdrEnv name_env rdr_name name
- in
- setLocalNameEnv new_name_env (enclosed_scope name) `thenRn` \ (result, fvs) ->
- returnRn (result, delFromNameSet fvs name)
-
-bindCoreLocalsFVRn [] thing_inside = thing_inside []
-bindCoreLocalsFVRn (b:bs) thing_inside = bindCoreLocalFVRn b $ \ name' ->
- bindCoreLocalsFVRn bs $ \ names' ->
- thing_inside (name':names')
-
--------------------------------------
-bindLocalRn doc rdr_name enclosed_scope
- = getSrcLocRn `thenRn` \ loc ->
- bindLocatedLocalsRn doc [(rdr_name,loc)] $ \ (n:ns) ->
- ASSERT( null ns )
- enclosed_scope n
-
-bindLocalsRn doc rdr_names enclosed_scope
- = getSrcLocRn `thenRn` \ loc ->
- bindLocatedLocalsRn doc
- (rdr_names `zip` repeat loc)
- enclosed_scope
-
- -- binLocalsFVRn is the same as bindLocalsRn
- -- except that it deals with free vars
-bindLocalsFVRn doc rdr_names enclosed_scope
- = bindLocalsRn doc rdr_names $ \ names ->
- enclosed_scope names `thenRn` \ (thing, fvs) ->
- returnRn (thing, delListFromNameSet fvs names)
-
--------------------------------------
-bindUVarRn :: SDoc -> RdrName -> (Name -> RnMS (a, FreeVars)) -> RnMS (a, FreeVars)
-bindUVarRn = bindLocalRn
-
--------------------------------------
-extendTyVarEnvFVRn :: [HsTyVar Name] -> RnMS (a, FreeVars) -> RnMS (a, FreeVars)
- -- This tiresome function is used only in rnDecl on InstDecl
-extendTyVarEnvFVRn tyvars enclosed_scope
- = getLocalNameEnv `thenRn` \ env ->
- let
- tyvar_names = map getTyVarName tyvars
- new_env = addListToRdrEnv env [ (mkRdrUnqual (getOccName name), name)
- | name <- tyvar_names
- ]
- in
- setLocalNameEnv new_env enclosed_scope `thenRn` \ (thing, fvs) ->
- returnRn (thing, delListFromNameSet fvs tyvar_names)
-
-bindTyVarsRn :: SDoc -> [HsTyVar RdrName]
- -> ([HsTyVar Name] -> RnMS a)
- -> RnMS a
-bindTyVarsRn doc_str tyvar_names enclosed_scope
- = bindTyVars2Rn doc_str tyvar_names $ \ names tyvars ->
- enclosed_scope tyvars
-
--- Gruesome name: return Names as well as HsTyVars
-bindTyVars2Rn :: SDoc -> [HsTyVar RdrName]
- -> ([Name] -> [HsTyVar Name] -> RnMS a)
- -> RnMS a
-bindTyVars2Rn doc_str tyvar_names enclosed_scope
- = getSrcLocRn `thenRn` \ loc ->
- let
- located_tyvars = [(getTyVarName tv, loc) | tv <- tyvar_names]
- in
- bindLocatedLocalsRn doc_str located_tyvars $ \ names ->
- enclosed_scope names (zipWith replaceTyVarName tyvar_names names)
-
-bindTyVarsFVRn :: SDoc -> [HsTyVar RdrName]
- -> ([HsTyVar Name] -> RnMS (a, FreeVars))
- -> RnMS (a, FreeVars)
-bindTyVarsFVRn doc_str rdr_names enclosed_scope
- = bindTyVars2Rn doc_str rdr_names $ \ names tyvars ->
- enclosed_scope tyvars `thenRn` \ (thing, fvs) ->
- returnRn (thing, delListFromNameSet fvs names)
-
-bindTyVarsFV2Rn :: SDoc -> [HsTyVar RdrName]
- -> ([Name] -> [HsTyVar Name] -> RnMS (a, FreeVars))
- -> RnMS (a, FreeVars)
-bindTyVarsFV2Rn doc_str rdr_names enclosed_scope
- = bindTyVars2Rn doc_str rdr_names $ \ names tyvars ->
- enclosed_scope names tyvars `thenRn` \ (thing, fvs) ->
- returnRn (thing, delListFromNameSet fvs names)
-
-
--------------------------------------
-checkDupOrQualNames, checkDupNames :: SDoc
- -> [(RdrName, SrcLoc)]
- -> RnM d ()
- -- Works in any variant of the renamer monad
-
-checkDupOrQualNames doc_str rdr_names_w_loc
- = -- Check for use of qualified names
- mapRn_ (qualNameErr doc_str) quals `thenRn_`
- checkDupNames doc_str rdr_names_w_loc
+-------------------------
+lookupGreRn :: RdrName -> RnM (Maybe GlobalRdrElt)
+-- Just look up the RdrName in the GlobalRdrEnv
+lookupGreRn rdr_name
+ = lookupGreRn_help rdr_name (lookupGRE_RdrName rdr_name)
+
+lookupGreLocalRn :: RdrName -> RnM (Maybe GlobalRdrElt)
+-- Similar, but restricted to locally-defined things
+lookupGreLocalRn rdr_name
+ = lookupGreRn_help rdr_name lookup_fn
where
- quals = filter (isQual.fst) rdr_names_w_loc
-
-checkDupNames doc_str rdr_names_w_loc
- = -- Check for duplicated names in a binding group
- mapRn_ (dupNamesErr doc_str) dups
+ lookup_fn env = filter isLocalGRE (lookupGRE_RdrName rdr_name env)
+
+lookupGreRn_help :: RdrName -- Only used in error message
+ -> (GlobalRdrEnv -> [GlobalRdrElt]) -- Lookup function
+ -> RnM (Maybe GlobalRdrElt)
+-- Checks for exactly one match; reports deprecations
+-- Returns Nothing, without error, if too few
+lookupGreRn_help rdr_name lookup
+ = do { env <- getGlobalRdrEnv
+ ; case lookup env of
+ [] -> returnM Nothing
+ [gre] -> returnM (Just gre)
+ gres -> do { addNameClashErrRn rdr_name gres
+ ; returnM (Just (head gres)) } }
+
+------------------------------
+-- GHCi support
+------------------------------
+
+-- A qualified name on the command line can refer to any module at all: we
+-- try to load the interface if we don't already have it.
+lookupQualifiedName :: RdrName -> RnM Name
+lookupQualifiedName rdr_name
+ = let
+ mod = rdrNameModule rdr_name
+ occ = rdrNameOcc rdr_name
+ in
+ loadSrcInterface doc mod False `thenM` \ iface ->
+
+ case [ (mod,occ) |
+ (mod,avails) <- mi_exports iface,
+ avail <- avails,
+ name <- availNames avail,
+ name == occ ] of
+ ((mod,occ):ns) -> ASSERT (null ns)
+ lookupOrig mod occ
+ _ -> unboundName rdr_name
where
- (_, dups) = removeDups (\(n1,l1) (n2,l2) -> n1 `compare` n2) rdr_names_w_loc
+ doc = ptext SLIT("Need to find") <+> ppr rdr_name
\end{code}
-
%*********************************************************
%* *
-\subsection{Looking up names}
+ Fixities
%* *
%*********************************************************
-Looking up a name in the RnEnv.
-
\begin{code}
-lookupBndrRn rdr_name
- = getNameEnvs `thenRn` \ (global_env, local_env) ->
-
- -- Try local env
- case lookupRdrEnv local_env rdr_name of {
- Just name -> returnRn name ;
- Nothing ->
-
- getModeRn `thenRn` \ mode ->
- case mode of
- InterfaceMode -> -- Look in the global name cache
- mkImportedGlobalFromRdrName rdr_name
-
- SourceMode -> -- Source mode, so look up a *qualified* version
- -- of the name, so that we get the right one even
- -- if there are many with the same occ name
- -- There must *be* a binding
- getModuleRn `thenRn` \ mod ->
- case lookupRdrEnv global_env (qualifyRdrName mod rdr_name) of
- Just (name:rest) -> ASSERT( null rest )
- returnRn name
- Nothing -> pprPanic "lookupBndrRn" (ppr mod <+> ppr rdr_name)
- }
-
--- Just like lookupRn except that we record the occurrence too
--- Perhaps surprisingly, even wired-in names are recorded.
--- Why? So that we know which wired-in names are referred to when
--- deciding which instance declarations to import.
-lookupOccRn :: RdrName -> RnMS Name
-lookupOccRn rdr_name
- = getNameEnvs `thenRn` \ (global_env, local_env) ->
- lookup_occ global_env local_env rdr_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
-lookupGlobalOccRn :: RdrName -> RnMS Name
-lookupGlobalOccRn rdr_name
- = getNameEnvs `thenRn` \ (global_env, local_env) ->
- lookup_global_occ global_env rdr_name
-
--- Look in both local and global env
-lookup_occ global_env local_env rdr_name
- = case lookupRdrEnv local_env rdr_name of
- Just name -> returnRn name
- Nothing -> lookup_global_occ global_env rdr_name
-
--- Look in global env only
-lookup_global_occ global_env rdr_name
- = case lookupRdrEnv global_env rdr_name of
- Just [name] -> returnRn name
- Just stuff@(name:_) -> addNameClashErrRn rdr_name stuff `thenRn_`
- returnRn name
- Nothing -> getModeRn `thenRn` \ mode ->
- case mode of
- -- Not found when processing source code; so fail
- SourceMode -> failWithRn (mkUnboundName rdr_name)
- (unknownNameErr rdr_name)
-
- -- Not found when processing an imported declaration,
- -- so we create a new name for the purpose
- InterfaceMode -> mkImportedGlobalFromRdrName rdr_name
+lookupTopFixSigNames :: RdrName -> RnM [Name]
+-- GHC extension: look up both the tycon and data con
+-- for con-like things
+lookupTopFixSigNames 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)
+ ; return [gre_name gre | Just gre <- mb_gres] }
+
+--------------------------------
+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
+ where
+ rn_sig (FixitySig lv@(L loc v) fix)
+ = addLocM lookupBndrRn lv `thenM` \ new_v ->
+ returnM (new_v, (FixItem (rdrNameOcc v) fix loc))
\end{code}
-%
-@lookupImplicitOccRn@ takes an RdrName representing an {\em original} name,
-and adds it to the occurrence pool so that it'll be loaded later.
-This is used when language constructs
-(such as monad comprehensions, overloaded literals, or deriving clauses)
-require some stuff to be loaded that isn't explicitly mentioned in the code.
-This doesn't apply in interface mode, where everything is explicit,
-but we don't check for this case:
-it does no harm to record an ``extra'' occurrence
-and @lookupImplicitOccRn@ isn't used much in interface mode
-(it's only the @Nothing@ clause of @rnDerivs@ that calls it at all I think).
+--------------------------------
+lookupFixity is a bit strange.
- \fbox{{\em Jan 98: this comment is wrong: @rnHsType@ uses it quite a bit.}}
+* Nested local fixity decls are put in the local fixity env, which we
+ find with getFixtyEnv
-For List and Tuple types it's important to get the correct
-@isLocallyDefined@ flag, which is used in turn when deciding
-whether there are any instance decls in this module are ``special''.
-The name cache should have the correct provenance, though.
+* Imported fixities are found in the HIT or PIT
-\begin{code}
-lookupImplicitOccRn :: RdrName -> RnM d Name
-lookupImplicitOccRn rdr_name = mkImportedGlobalFromRdrName rdr_name
-\end{code}
-
-@unQualInScope@ returns a function that takes a @Name@ and tells whether
-its unqualified name is in scope. This is put as a boolean flag in
-the @Name@'s provenance to guide whether or not to print the name qualified
-in error messages.
+* Top-level fixity decls in this module may be for Names that are
+ either Global (constructors, class operations)
+ or Local/Exported (everything else)
+ (See notes with RnNames.getLocalDeclBinders for why we have this split.)
+ We put them all in the local fixity environment
\begin{code}
-unQualInScope :: GlobalRdrEnv -> Name -> Bool
-unQualInScope env
- = lookup
+lookupFixityRn :: Name -> RnM Fixity
+lookupFixityRn name
+ = 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)
+
+ else -- It's imported
+ -- For imported names, we have to get their fixities by doing a
+ -- loadHomeInterface, and consulting the Ifaces that comes back
+ -- from that, because the interface file for the Name might not
+ -- have been loaded yet. Why not? Suppose you import module A,
+ -- which exports a function 'f', thus;
+ -- module CurrentModule where
+ -- import A( f )
+ -- module A( f ) where
+ -- import B( f )
+ -- Then B isn't loaded right away (after all, it's possible that
+ -- nothing from B will be used). When we come across a use of
+ -- 'f', we need to know its fixity, and it's then, and only
+ -- then, that we load B.hi. That is what's happening here.
+ loadSrcInterface doc name_mod False `thenM` \ iface ->
+ returnM (mi_fix_fn iface (nameOccName name))
where
- lookup name = case lookupRdrEnv env (mkRdrUnqual (nameOccName name)) of
- Just [name'] -> name == name'
- other -> False
+ doc = ptext SLIT("Checking fixity for") <+> ppr name
+ name_mod = nameModuleName name
+
+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.
+--
+-- ToDo: If the user typed "[]" or "(,,)", we'll generate an Exact RdrName,
+-- and we don't have a systematic way to find the TyCon's Name from
+-- the DataCon's name. Sigh
+dataTcOccs rdr_name
+ | isDataOcc occ = [rdr_name_tc, rdr_name]
+ | otherwise = [rdr_name]
+ where
+ occ = rdrNameOcc rdr_name
+ rdr_name_tc = setRdrNameSpace rdr_name tcName
\end{code}
%************************************************************************
%* *
-\subsection{Envt utility functions}
+ Rebindable names
+ Dealing with rebindable syntax is driven by the
+ Opt_NoImplicitPrelude dynamic flag.
+
+ In "deriving" code we don't want to use rebindable syntax
+ so we switch off the flag locally
+
%* *
%************************************************************************
-\subsubsection{NameEnv}% ================
+Haskell 98 says that when you say "3" you get the "fromInteger" from the
+Standard Prelude, regardless of what is in scope. However, to experiment
+with having a language that is less coupled to the standard prelude, we're
+trying a non-standard extension that instead gives you whatever "Prelude.fromInteger"
+happens to be in scope. Then you can
+ import Prelude ()
+ import MyPrelude as Prelude
+to get the desired effect.
+
+At the moment this just happens for
+ * fromInteger, fromRational on literals (in expressions and patterns)
+ * negate (in expressions)
+ * minus (arising from n+k patterns)
+ * "do" notation
+
+We store the relevant Name in the HsSyn tree, in
+ * HsIntegral/HsFractional
+ * NegApp
+ * NPlusKPatIn
+ * HsDo
+respectively. Initially, we just store the "standard" name (PrelNames.fromIntegralName,
+fromRationalName etc), but the renamer changes this to the appropriate user
+name if Opt_NoImplicitPrelude is on. That is what lookupSyntaxName does.
+
+We treat the orignal (standard) names as free-vars too, because the type checker
+checks the type of the user thing against the type of the standard thing.
\begin{code}
-plusGlobalRdrEnv :: GlobalRdrEnv -> GlobalRdrEnv -> GlobalRdrEnv
-plusGlobalRdrEnv env1 env2 = plusFM_C combine_globals env1 env2
-
-addOneToGlobalRdrEnv :: GlobalRdrEnv -> RdrName -> Name -> GlobalRdrEnv
-addOneToGlobalRdrEnv env rdr_name name = addToFM_C combine_globals env rdr_name [name]
-
-delOneFromGlobalRdrEnv :: GlobalRdrEnv -> RdrName -> GlobalRdrEnv
-delOneFromGlobalRdrEnv env rdr_name = delFromFM env rdr_name
-
-combine_globals :: [Name] -- Old
- -> [Name] -- New
- -> [Name]
-combine_globals ns_old ns_new -- ns_new is often short
- = foldr add ns_old ns_new
+lookupSyntaxName :: Name -- The standard name
+ -> RnM (Name, FreeVars) -- Possibly a non-standard name
+lookupSyntaxName std_name
+ = doptM Opt_NoImplicitPrelude `thenM` \ no_prelude ->
+ if not no_prelude then normal_case
+ else
+ -- Get the similarly named thing from the local environment
+ lookupOccRn (mkRdrUnqual (nameOccName std_name)) `thenM` \ usr_name ->
+ returnM (usr_name, unitFV usr_name)
where
- add n ns | any (is_duplicate n) ns_old = map choose ns -- Eliminate duplicates
- | otherwise = n:ns
- where
- choose n' | n==n' && better_provenance n n' = n
- | otherwise = n'
-
--- Choose
--- a local thing over an imported thing
--- a user-imported thing over a non-user-imported thing
--- an explicitly-imported thing over an implicitly imported thing
-better_provenance n1 n2
- = case (getNameProvenance n1, getNameProvenance n2) of
- (LocalDef _ _, _ ) -> True
- (NonLocalDef (UserImport _ _ True) _, _ ) -> True
- (NonLocalDef (UserImport _ _ _ ) _, NonLocalDef ImplicitImport _) -> True
- other -> False
-
-is_duplicate :: Name -> Name -> Bool
-is_duplicate n1 n2 | isLocallyDefined n1 && isLocallyDefined n2 = False
- | otherwise = n1 == n2
+ normal_case = returnM (std_name, emptyFVs)
+
+lookupSyntaxNames :: [Name] -- Standard names
+ -> RnM (ReboundNames Name, FreeVars) -- See comments with HsExpr.ReboundNames
+lookupSyntaxNames std_names
+ = doptM Opt_NoImplicitPrelude `thenM` \ no_prelude ->
+ if not no_prelude then normal_case
+ else
+ -- Get the similarly named thing from the local environment
+ mappM (lookupOccRn . mkRdrUnqual . nameOccName) std_names `thenM` \ usr_names ->
+
+ returnM (std_names `zip` map nlHsVar usr_names, mkFVs usr_names)
+ where
+ normal_case = returnM (std_names `zip` map nlHsVar std_names, emptyFVs)
\end{code}
-We treat two bindings of a locally-defined name as a duplicate,
-because they might be two separate, local defns and we want to report
-and error for that, {\em not} eliminate a duplicate.
-
-On the other hand, if you import the same name from two different
-import statements, we {\em d}* want to eliminate the duplicate, not report
-an error.
-If a module imports itself then there might be a local defn and an imported
-defn of the same name; in this case the names will compare as equal, but
-will still have different provenances.
-
-
-\subsubsection{AvailInfo}% ================
+%*********************************************************
+%* *
+\subsection{Binding}
+%* *
+%*********************************************************
\begin{code}
-plusAvail (Avail n1) (Avail n2) = Avail n1
-plusAvail (AvailTC n1 ns1) (AvailTC n2 ns2) = AvailTC n2 (nub (ns1 ++ ns2))
--- Added SOF 4/97
-#ifdef DEBUG
-plusAvail a1 a2 = pprPanic "RnEnv.plusAvail" (hsep [pprAvail a1,pprAvail a2])
-#endif
+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]
+ -> ([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_`
-addAvail :: AvailEnv -> AvailInfo -> AvailEnv
-addAvail avails avail = addToNameEnv_C plusAvail avails (availName avail) avail
+ -- Warn about shadowing, but only in source modules
+ ifOptM Opt_WarnNameShadowing
+ (checkShadowing doc_str rdr_names_w_loc) `thenM_`
-emptyAvailEnv = emptyNameEnv
-unitAvailEnv :: AvailInfo -> AvailEnv
-unitAvailEnv a = unitNameEnv (availName a) a
+ -- 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)
-plusAvailEnv :: AvailEnv -> AvailEnv -> AvailEnv
-plusAvailEnv = plusNameEnv_C plusAvail
-availEnvElts = nameEnvElts
+bindLocalNames names enclosed_scope
+ = getLocalRdrEnv `thenM` \ name_env ->
+ setLocalRdrEnv (extendLocalRdrEnv name_env names)
+ enclosed_scope
-addAvailToNameSet :: NameSet -> AvailInfo -> NameSet
-addAvailToNameSet names avail = addListToNameSet names (availNames avail)
+bindLocalNamesFV names enclosed_scope
+ = bindLocalNames names $
+ enclosed_scope `thenM` \ (thing, fvs) ->
+ returnM (thing, delListFromNameSet fvs names)
-availsToNameSet :: [AvailInfo] -> NameSet
-availsToNameSet avails = foldl addAvailToNameSet emptyNameSet avails
-availName :: AvailInfo -> Name
-availName (Avail n) = n
-availName (AvailTC n _) = n
+-------------------------------------
+ -- 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 ->
+ enclosed_scope names `thenM` \ (thing, fvs) ->
+ returnM (thing, delListFromNameSet fvs names)
-availNames :: AvailInfo -> [Name]
-availNames (Avail n) = [n]
-availNames (AvailTC n ns) = ns
+-------------------------------------
+extendTyVarEnvFVRn :: [Name] -> RnM (a, FreeVars) -> RnM (a, FreeVars)
+ -- This tiresome function is used only in rnSourceDecl on InstDecl
+extendTyVarEnvFVRn tyvars enclosed_scope
+ = bindLocalNames tyvars enclosed_scope `thenM` \ (thing, fvs) ->
+ returnM (thing, delListFromNameSet fvs tyvars)
-addSysAvails :: AvailInfo -> [Name] -> AvailInfo
-addSysAvails avail [] = avail
-addSysAvails (AvailTC n ns) sys = AvailTC n (sys ++ ns)
+bindTyVarsRn :: SDoc -> [LHsTyVarBndr RdrName]
+ -> ([LHsTyVarBndr Name] -> RnM a)
+ -> RnM a
+bindTyVarsRn doc_str tyvar_names enclosed_scope
+ = let
+ located_tyvars = [L loc (hsTyVarName tv) | L loc tv <- 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)
+
+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
+ = getLocalRdrEnv `thenM` \ name_env ->
+ let
+ located_tyvars = nubBy eqLocated [ tv | ty <- tys,
+ tv <- extractHsTyRdrTyVars ty,
+ not (unLoc tv `elemLocalRdrEnv` name_env)
+ ]
+ -- The 'nub' is important. For example:
+ -- f (x :: t) (y :: t) = ....
+ -- We don't want to complain about binding t twice!
+
+ doc_sig = text "In a pattern type-signature"
+ in
+ bindLocatedLocalsRn doc_sig located_tyvars thing_inside
-filterAvail :: RdrNameIE -- Wanted
- -> AvailInfo -- Available
- -> Maybe AvailInfo -- Resulting available;
- -- Nothing if (any of the) wanted stuff isn't there
+bindPatSigTyVarsFV :: [LHsType RdrName]
+ -> RnM (a, FreeVars)
+ -> RnM (a, FreeVars)
+bindPatSigTyVarsFV tys thing_inside
+ = bindPatSigTyVars tys $ \ tvs ->
+ thing_inside `thenM` \ (result,fvs) ->
+ returnM (result, fvs `delListFromNameSet` tvs)
-filterAvail ie@(IEThingWith want wants) avail@(AvailTC n ns)
- | sub_names_ok = Just (AvailTC n (filter is_wanted ns))
- | otherwise = Nothing
+-------------------------------------
+checkDupNames :: SDoc
+ -> [Located RdrName]
+ -> RnM ()
+checkDupNames doc_str rdr_names_w_loc
+ = -- Check for duplicated names in a binding group
+ mappM_ (dupNamesErr doc_str) dups
where
- is_wanted name = nameOccName name `elem` wanted_occs
- sub_names_ok = all (`elem` avail_occs) wanted_occs
- avail_occs = map nameOccName ns
- wanted_occs = map rdrNameOcc (want:wants)
-
-filterAvail (IEThingAbs _) (AvailTC n ns) = ASSERT( n `elem` ns )
- Just (AvailTC n [n])
-
-filterAvail (IEThingAbs _) avail@(Avail n) = Just avail -- Type synonyms
-
-filterAvail (IEVar _) avail@(Avail n) = Just avail
-filterAvail (IEVar v) avail@(AvailTC n ns) = Just (AvailTC n (filter wanted ns))
- where
- wanted n = nameOccName n == occ
- occ = rdrNameOcc v
- -- The second equation happens if we import a class op, thus
- -- import A( op )
- -- where op is a class operation
-
-filterAvail (IEThingAll _) avail@(AvailTC _ _) = Just avail
- -- We don't complain even if the IE says T(..), but
- -- no constrs/class ops of T are available
- -- Instead that's caught with a warning by the caller
-
-filterAvail ie avail = Nothing
-
-pprAvail :: AvailInfo -> SDoc
-pprAvail (AvailTC n ns) = ppr n <> case filter (/= n) ns of
- [] -> empty
- ns' -> parens (hsep (punctuate comma (map ppr ns')))
-
-pprAvail (Avail n) = ppr n
-\end{code}
-
+ (_, dups) = removeDups (\n1 n2 -> unLoc n1 `compare` unLoc n2) rdr_names_w_loc
+-------------------------------------
+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 ))
+ = addSrcSpan loc $ addWarn (shadowedNameWarn doc_str rdr_name)
+ | otherwise = returnM ()
+ in
+ mappM_ check_shadow loc_rdr_names
+\end{code}
%************************************************************************
%************************************************************************
\begin{code}
-type FreeVars = NameSet
-
-plusFV :: FreeVars -> FreeVars -> FreeVars
-addOneFV :: FreeVars -> Name -> FreeVars
-unitFV :: Name -> FreeVars
-emptyFVs :: FreeVars
-plusFVs :: [FreeVars] -> FreeVars
-
-isEmptyFVs = isEmptyNameSet
-emptyFVs = emptyNameSet
-plusFVs = unionManyNameSets
-plusFV = unionNameSets
-
--- No point in adding implicitly imported names to the free-var set
-addOneFV s n = addOneToNameSet s n
-unitFV n = unitNameSet n
-
-- A useful utility
-mapFvRn f xs = mapRn f xs `thenRn` \ stuff ->
+mapFvRn f xs = mappM f xs `thenM` \ stuff ->
let
(ys, fvs_s) = unzip stuff
in
- returnRn (ys, plusFVs fvs_s)
+ returnM (ys, plusFVs fvs_s)
\end{code}
%* *
%************************************************************************
-
-
\begin{code}
-warnUnusedModules :: [ModuleName] -> RnM d ()
+warnUnusedModules :: [ModuleName] -> RnM ()
warnUnusedModules mods
- | not opt_WarnUnusedImports = returnRn ()
- | otherwise = mapRn_ (addWarnRn . unused_mod) mods
+ = ifOptM Opt_WarnUnusedImports (mappM_ (addWarn . unused_mod) mods)
where
- unused_mod m = ptext SLIT("Module") <+> quotes (pprModuleName m) <+>
- text "is imported, but nothing from it is used"
-
-warnUnusedLocalBinds, warnUnusedImports, warnUnusedMatches :: [Name] -> RnM d ()
-warnUnusedImports names
- | not opt_WarnUnusedImports
- = returnRn () -- Don't force names unless necessary
- | otherwise
- = warnUnusedBinds (const True) names
+ unused_mod m = vcat [ptext SLIT("Module") <+> quotes (ppr m) <+>
+ text "is imported, but nothing from it is used",
+ parens (ptext SLIT("except perhaps instances visible in") <+>
+ quotes (ppr m))]
-warnUnusedLocalBinds ns
- | not opt_WarnUnusedBinds = returnRn ()
- | otherwise = warnUnusedBinds (const True) ns
+warnUnusedImports, warnUnusedTopBinds :: [GlobalRdrElt] -> RnM ()
+warnUnusedImports gres = ifOptM Opt_WarnUnusedImports (warnUnusedGREs gres)
+warnUnusedTopBinds gres = ifOptM Opt_WarnUnusedBinds (warnUnusedGREs gres)
-warnUnusedMatches names
- | opt_WarnUnusedMatches = warnUnusedGroup (const True) names
- | otherwise = returnRn ()
+warnUnusedLocalBinds, warnUnusedMatches :: [Name] -> RnM ()
+warnUnusedLocalBinds names = ifOptM Opt_WarnUnusedBinds (warnUnusedLocals names)
+warnUnusedMatches names = ifOptM Opt_WarnUnusedMatches (warnUnusedLocals names)
-------------------------
+-- Helpers
+warnUnusedGREs gres
+ = warnUnusedBinds [(n,Just p) | GRE {gre_name = n, gre_prov = p} <- gres]
-warnUnusedBinds :: (Bool -> Bool) -> [Name] -> RnM d ()
-warnUnusedBinds warn_when_local names
- = mapRn_ (warnUnusedGroup warn_when_local) groups
- where
- -- Group by provenance
- groups = equivClasses cmp names
- name1 `cmp` name2 = getNameProvenance name1 `cmp_prov` getNameProvenance name2
-
- cmp_prov (LocalDef _ _) (NonLocalDef _ _) = LT
- cmp_prov (LocalDef loc1 _) (LocalDef loc2 _) = loc1 `compare` loc2
- cmp_prov (NonLocalDef (UserImport m1 loc1 _) _)
- (NonLocalDef (UserImport m2 loc2 _) _) =
- (m1 `compare` m2) `thenCmp` (loc1 `compare` loc2)
- cmp_prov (NonLocalDef _ _) (LocalDef _ _) = GT
- -- In-scope NonLocalDefs must have UserImport info on them
+warnUnusedLocals names
+ = warnUnusedBinds [(n,Nothing) | n<-names]
--------------------------
+warnUnusedBinds :: [(Name,Maybe Provenance)] -> RnM ()
+warnUnusedBinds names = mappM_ warnUnusedName (filter reportable names)
+ where reportable (name,_) = reportIfUnused (nameOccName name)
--- NOTE: the function passed to warnUnusedGroup is
--- now always (const True) so we should be able to
--- simplify the code slightly. I'm leaving it there
--- for now just in case I havn't realised why it was there.
--- Looks highly bogus to me. SLPJ Dec 99
+-------------------------
-warnUnusedGroup :: (Bool -> Bool) -> [Name] -> RnM d ()
-warnUnusedGroup emit_warning names
- | null filtered_names = returnRn ()
- | not (emit_warning is_local) = returnRn ()
- | otherwise
- = pushSrcLocRn def_loc $
- addWarnRn $
- sep [msg <> colon, nest 4 (fsep (punctuate comma (map ppr filtered_names)))]
+warnUnusedName :: (Name, Maybe Provenance) -> RnM ()
+warnUnusedName (name, prov)
+ = addWarnAt loc (sep [msg <> colon, nest 4 (ppr name)])
+ -- TODO should be a proper span
where
- filtered_names = filter reportable names
- name1 = head filtered_names
- (is_local, def_loc, msg)
- = case getNameProvenance name1 of
- LocalDef loc _ -> (True, loc, text "Defined but not used")
- NonLocalDef (UserImport mod loc _) _ ->
- (True, loc, text "Imported from" <+> quotes (ppr mod) <+>
- text "but not used")
- other -> (False, getSrcLoc name1, text "Strangely defined but not used")
-
- reportable name = case occNameUserString (nameOccName name) of
- ('_' : _) -> False
- zz_other -> True
- -- Haskell 98 encourages compilers to suppress warnings about
- -- unused names in a pattern if they start with "_".
+ (loc,msg) = case prov of
+ Just (Imported is _) ->
+ ( is_loc (head is), imp_from (is_mod imp_spec) )
+ where
+ imp_spec = head is
+ other ->
+ ( srcLocSpan (nameSrcLoc name), unused_msg )
+
+ unused_msg = text "Defined but not used"
+ imp_from mod = text "Imported from" <+> quotes (ppr mod) <+> text "but not used"
\end{code}
\begin{code}
-addNameClashErrRn rdr_name (name1:names)
- = addErrRn (vcat [ptext SLIT("Ambiguous occurrence") <+> quotes (ppr rdr_name),
- ptext SLIT("It could refer to") <+> vcat (msg1 : msgs)])
+addNameClashErrRn rdr_name (np1:nps)
+ = addErr (vcat [ptext SLIT("Ambiguous occurrence") <+> quotes (ppr rdr_name),
+ ptext SLIT("It could refer to") <+> vcat (msg1 : msgs)])
where
- msg1 = ptext SLIT("either") <+> mk_ref name1
- msgs = [ptext SLIT(" or") <+> mk_ref name | name <- names]
- mk_ref name = quotes (ppr name) <> comma <+> pprNameProvenance name
+ 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
-fixityClashErr (rdr_name, ((_,how_in_scope1), (_, how_in_scope2)))
- = hang (hsep [ptext SLIT("Conflicting fixities for"), quotes (ppr rdr_name)])
- 4 (vcat [ppr how_in_scope1,
- ppr how_in_scope2])
-
-shadowedNameWarn shadow
+shadowedNameWarn doc shadow
= hsep [ptext SLIT("This binding for"),
quotes (ppr shadow),
ptext SLIT("shadows an existing binding")]
+ $$ doc
unknownNameErr name
- = sep [text flavour, ptext SLIT("not in scope:"), quotes (ppr name)]
+ = sep [ptext SLIT("Not in scope:"),
+ if isVarOcc occ_name then quotes (ppr name)
+ else text (occNameFlavour occ_name)
+ <+> quotes (ppr name)]
where
- flavour = occNameFlavour (rdrNameOcc name)
-
-qualNameErr descriptor (name,loc)
- = pushSrcLocRn loc $
- addErrRn (hsep [ ptext SLIT("Invalid use of qualified name"),
- quotes (ppr name),
- ptext SLIT("in"),
- descriptor])
-
-dupNamesErr descriptor ((name,loc) : dup_things)
- = pushSrcLocRn loc $
- addErrRn ((ptext SLIT("Conflicting definitions for") <+> quotes (ppr name))
+ occ_name = rdrNameOcc name
+
+unknownInstBndrErr cls op
+ = quotes (ppr op) <+> ptext SLIT("is not a (visible) method of class") <+> quotes (ppr cls)
+
+badOrigBinding name
+ = ptext SLIT("Illegal binding of built-in syntax:") <+> ppr (rdrNameOcc name)
+ -- The rdrNameOcc is because we don't want to print Prelude.(,)
+
+dupNamesErr descriptor (L loc name : dup_things)
+ = addSrcSpan loc $
+ addErr ((ptext SLIT("Conflicting definitions for") <+> quotes (ppr name))
$$
- (ptext SLIT("in") <+> descriptor))
+ descriptor)
\end{code}