%
-% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
%
\section[RnEnv]{Environment manipulation for the renamer monad}
\begin{code}
-#include "HsVersions.h"
-
module RnEnv where -- Export everything
-IMPORT_1_3(List (nub))
-IMP_Ubiq()
+#include "HsVersions.h"
-import CmdLineOpts ( opt_WarnNameShadowing )
+import {-# SOURCE #-} RnHiFiles( loadInterface )
+
+import FlattenInfo ( namesNeededForFlattening )
import HsSyn
-import RdrHsSyn ( RdrName(..), SYN_IE(RdrNameIE),
- rdrNameOcc, ieOcc, isQual, qual
+import RdrHsSyn ( RdrNameHsType, RdrNameFixitySig, extractHsTyRdrTyVars )
+import RdrName ( RdrName, rdrNameModule, rdrNameOcc, isQual, isUnqual, isOrig,
+ mkRdrUnqual, mkRdrQual, setRdrNameSpace, rdrNameOcc,
+ lookupRdrEnv, rdrEnvToList, elemRdrEnv,
+ extendRdrEnv, addListToRdrEnv, emptyRdrEnv,
+ isExact_maybe, unqualifyRdrName
+ )
+import HsTypes ( hsTyVarName, replaceTyVarName )
+import HscTypes ( Provenance(..), pprNameProvenance, hasBetterProv,
+ ImportReason(..), GlobalRdrEnv, GlobalRdrElt(..),
+ GenAvailInfo(..), AvailInfo, Avails,
+ ModIface(..), NameCache(..), OrigNameCache,
+ Deprecations(..), lookupDeprec, isLocalGRE,
+ extendLocalRdrEnv, availName, availNames,
+ lookupFixity
)
-import HsTypes ( getTyVarName, replaceTyVarName )
-import BasicTypes ( Fixity(..), FixityDirection(..) )
-import RnMonad
-import Name ( Name, OccName(..), Provenance(..), DefnInfo(..), ExportFlag(..), NamedThing(..),
- occNameString, occNameFlavour,
- SYN_IE(NameSet), emptyNameSet, addListToNameSet,
- mkLocalName, mkGlobalName, modAndOcc, isLocallyDefinedName,
- isWiredInName, nameOccName, setNameProvenance, isVarOcc, getNameProvenance,
- pprProvenance, pprOccName, pprModule, pprNameProvenance
+import TcRnMonad
+import Name ( Name, getName, getSrcLoc, nameIsLocalOrFrom, isWiredInName,
+ mkInternalName, mkExternalName, mkIPName, nameSrcLoc,
+ nameOccName, setNameSrcLoc, nameModule )
+import NameSet
+import OccName ( OccName, tcName, isDataOcc, occNameUserString, occNameFlavour )
+import Module ( Module, ModuleName, moduleName, mkHomeModule,
+ lookupModuleEnv, lookupModuleEnvByName, extendModuleEnv_C )
+import PrelNames ( mkUnboundName, intTyConName,
+ boolTyConName, funTyConName,
+ unpackCStringName, unpackCStringFoldrName, unpackCStringUtf8Name,
+ eqStringName, printName,
+ bindIOName, returnIOName, failIOName, thenIOName
)
-import TyCon ( TyCon )
-import TysWiredIn ( tupleTyCon, listTyCon, charTyCon, intTyCon )
+#ifdef GHCI
+import DsMeta ( templateHaskellNames, qTyConName )
+#endif
+import TysWiredIn ( unitTyCon ) -- A little odd
+import Finder ( findModule )
import FiniteMap
-import Outputable
-import Unique ( Unique, unboundKey )
-import UniqFM ( Uniquable(..), listToUFM, plusUFM_C )
-import Maybes ( maybeToBool )
import UniqSupply
-import SrcLoc ( SrcLoc, noSrcLoc )
-import Pretty
-import Outputable ( PprStyle(..) )
-import Util --( panic, removeDups, pprTrace, assertPanic )
-
+import SrcLoc ( SrcLoc, noSrcLoc, importedSrcLoc )
+import Outputable
+import ListSetOps ( removeDups, equivClasses )
+import BasicTypes ( mapIPName, FixitySig(..) )
+import List ( nub )
+import CmdLineOpts
+import FastString ( FastString )
\end{code}
-
-
%*********************************************************
%* *
\subsection{Making new names}
%*********************************************************
\begin{code}
-newGlobalName :: Module -> OccName -> RnM s d Name
-newGlobalName mod occ
- = -- First check the cache
- getNameSupplyRn `thenRn` \ (us, inst_ns, cache) ->
- let key = (mod,occ) in
- case lookupFM cache key of
-
- -- A hit in the cache! Return it, but change the src loc
- -- of the thing we've found if this is a second definition site
- -- (that is, if loc /= NoSrcLoc)
- Just name -> returnRn name
-
- -- Miss in the cache, so build a new original name,
- -- and put it in the cache
- Nothing ->
- let
- (us', us1) = splitUniqSupply us
- uniq = getUnique us1
- name = mkGlobalName uniq mod occ VanillaDefn Implicit
- cache' = addToFM cache key name
- in
- setNameSupplyRn (us', inst_ns, cache') `thenRn_`
- returnRn name
-
-newLocallyDefinedGlobalName :: Module -> OccName
- -> (Name -> ExportFlag) -> SrcLoc
- -> RnM s d Name
-newLocallyDefinedGlobalName mod occ rec_exp_fn loc
+newTopBinder :: Module -> RdrName -> SrcLoc -> TcRn m Name
+newTopBinder mod rdr_name loc
+ | Just name <- isExact_maybe rdr_name
+ = returnM name
+
+ | otherwise
+ = ASSERT( not (isOrig rdr_name) || rdrNameModule rdr_name == moduleName mod )
+ -- When reading External Core we get Orig names as binders,
+ -- but they should agree with the module gotten from the monad
+ newGlobalName mod (rdrNameOcc rdr_name) loc
+
+newGlobalName :: Module -> OccName -> SrcLoc -> TcRn m Name
+newGlobalName mod occ loc
= -- First check the cache
- getNameSupplyRn `thenRn` \ (us, inst_ns, cache) ->
-
- -- We are at the binding site for a locally-defined thing, so
- -- you might think it can't be in the cache, but it can if it's a
- -- wired in thing. In that case we need to use the correct unique etc...
- -- so all we do is replace its provenance.
- -- If it's not in the cache we put it there with the correct provenance.
- -- The idea is that, after all this, the cache
- -- will contain a Name with the correct Provenance (i.e. Local)
-
- -- OLD (now wrong) COMMENT:
- -- "Actually, there's a catch. If this is the *second* binding for something
- -- we want to allocate a *fresh* unique, rather than using the same Name as before.
- -- Otherwise we don't detect conflicting definitions of the same top-level name!
- -- So the only time we re-use a Name already in the cache is when it's one of
- -- the Implicit magic-unique ones mentioned in the previous para"
-
- -- This (incorrect) patch doesn't work for record decls, when we have
- -- the same field declared in multiple constructors. With the above patch,
- -- each occurrence got a new Name --- aargh!
+ getNameCache `thenM` \ name_supply ->
+ case lookupOrigNameCache (nsNames name_supply) mod occ of
+
+ -- A hit in the cache! We are at the binding site of the name.
+ -- This is the moment when we know the defining SrcLoc
+ -- of the Name, so we set the SrcLoc of the name we return.
+ --
+ -- Main reason: then (bogus) multiple bindings of the same Name
+ -- get different SrcLocs can can be reported as such.
--
- -- So I reverted to the simple caching method (no "second-binding" thing)
- -- The multiple-local-binding case is now handled by improving the conflict
- -- detection in plusNameEnv.
+ -- Possible other reason: it might be in the cache because we
+ -- encountered an occurrence before the binding site for an
+ -- implicitly-imported Name. Perhaps the current SrcLoc is
+ -- better... but not really: it'll still just say 'imported'
+ --
+ -- IMPORTANT: Don't mess with wired-in names.
+ -- Their wired-in-ness is in the SrcLoc
+
+ Just name | isWiredInName name -> returnM name
+ | otherwise -> returnM (setNameSrcLoc name loc)
+
+ -- Miss in the cache!
+ -- Build a completely new Name, and put it in the cache
+ Nothing -> addNewName name_supply mod occ loc
+
+-- Look up a "system name" in the name cache.
+-- This is done by the type checker...
+lookupSysName :: Name -- Base name
+ -> (OccName -> OccName) -- Occurrence name modifier
+ -> TcRn m Name -- System name
+lookupSysName base_name mk_sys_occ
+ = newGlobalName (nameModule base_name)
+ (mk_sys_occ (nameOccName base_name))
+ (nameSrcLoc base_name)
+
+
+newGlobalNameFromRdrName rdr_name -- Qualified original name
+ = newGlobalName2 (rdrNameModule rdr_name) (rdrNameOcc rdr_name)
+
+newGlobalName2 :: ModuleName -> OccName -> TcRn m Name
+ -- This one starts with a ModuleName, not a Module, because
+ -- we may be simply looking at an occurrence M.x in an interface file.
+ --
+ -- Used for *occurrences*. Even if we get a miss in the
+ -- original-name cache, we make a new External Name.
+ -- We get its Module either from the OrigNameCache, or (if this
+ -- is the first Name from that module) from the Finder
+ --
+ -- In the case of a miss, we have to make up the SrcLoc, but that's
+ -- OK: it must be an implicitly-imported Name, and that never occurs
+ -- in an error message.
+
+newGlobalName2 mod_name occ
+ = getNameCache `thenM` \ name_supply ->
let
- provenance = LocalDef (rec_exp_fn new_name) loc
- (us', us1) = splitUniqSupply us
- uniq = getUnique us1
- key = (mod,occ)
- new_name = case lookupFM cache key of
- Just name -> setNameProvenance name provenance
- other -> mkGlobalName uniq mod occ VanillaDefn provenance
- new_cache = addToFM cache key new_name
+ new_name mod = addNewName name_supply mod occ importedSrcLoc
in
- setNameSupplyRn (us', inst_ns, new_cache) `thenRn_`
- returnRn new_name
-
--- newSysName is used to create the names for
--- a) default methods
--- These are never mentioned explicitly in source code (hence no point in looking
--- them up in the NameEnv), but when reading an interface file
--- we may want to slurp in their pragma info. In the source file itself we
--- need to create these names too so that we export them into the inferface file for this module.
-
-newSysName :: OccName -> ExportFlag -> SrcLoc -> RnMS s Name
-newSysName occ export_flag loc
- = getModeRn `thenRn` \ mode ->
- getModuleRn `thenRn` \ mod_name ->
- case mode of
- SourceMode -> newLocallyDefinedGlobalName
- mod_name occ
- (\_ -> export_flag)
- loc
- InterfaceMode _ -> newGlobalName mod_name occ
-
--- newDfunName is a variant, specially for dfuns.
--- When renaming derived definitions we are in *interface* mode (because we can trip
--- over original names), but we still want to make the Dfun locally-defined.
--- So we can't use whether or not we're in source mode to decide the locally-defined question.
-newDfunName :: Maybe RdrName -> SrcLoc -> RnMS s Name
-newDfunName Nothing src_loc -- Local instance decls have a "Nothing"
- = getModuleRn `thenRn` \ mod_name ->
- newInstUniq `thenRn` \ inst_uniq ->
+ case lookupModuleEnvByName (nsNames name_supply) mod_name of
+ Just (mod, occ_env) ->
+ -- There are some names from this module already
+ -- Next, look up in the OccNameEnv
+ case lookupFM occ_env occ of
+ Just name -> returnM name
+ Nothing -> new_name mod
+
+ Nothing -> -- No names from this module yet
+ ioToTcRn (findModule mod_name) `thenM` \ mb_loc ->
+ case mb_loc of
+ Right (mod, _) -> new_name mod
+ Left files ->
+ getDOpts `thenM` \ dflags ->
+ addErr (noIfaceErr dflags mod_name False files) `thenM_`
+ -- Things have really gone wrong at this point,
+ -- so having the wrong package info in the
+ -- Module is the least of our worries.
+ new_name (mkHomeModule mod_name)
+
+
+newIPName rdr_name_ip
+ = getNameCache `thenM` \ name_supply ->
let
- dfun_occ = VarOcc (_PK_ ("$d" ++ show inst_uniq))
+ ipcache = nsIPs name_supply
in
- newLocallyDefinedGlobalName mod_name dfun_occ
- (\_ -> Exported) src_loc
-
-newDfunName (Just n) src_loc -- Imported ones have "Just n"
- = getModuleRn `thenRn` \ mod_name ->
- newGlobalName mod_name (rdrNameOcc n)
+ case lookupFM ipcache key of
+ Just name_ip -> returnM name_ip
+ Nothing -> setNameCache new_ns `thenM_`
+ returnM name_ip
+ where
+ (us', us1) = splitUniqSupply (nsUniqs name_supply)
+ uniq = uniqFromSupply us1
+ name_ip = mapIPName mk_name rdr_name_ip
+ mk_name rdr_name = mkIPName uniq (rdrNameOcc rdr_name)
+ new_ipcache = addToFM ipcache key name_ip
+ new_ns = name_supply {nsUniqs = us', nsIPs = new_ipcache}
+ where
+ key = rdr_name_ip -- Ensures that ?x and %x get distinct Names
+
+-- A local helper function
+addNewName name_supply mod occ loc
+ = setNameCache new_name_supply `thenM_`
+ returnM name
+ where
+ (new_name_supply, name) = newExternalName name_supply mod occ loc
-newLocalNames :: [(RdrName,SrcLoc)] -> RnM s d [Name]
-newLocalNames rdr_names
- = getNameSupplyRn `thenRn` \ (us, inst_ns, cache) ->
- let
- n = length rdr_names
- (us', us1) = splitUniqSupply us
- uniqs = getUniques n us1
- locals = [ mkLocalName uniq (rdrNameOcc rdr_name) loc
- | ((rdr_name,loc), uniq) <- rdr_names `zip` uniqs
- ]
- in
- setNameSupplyRn (us', inst_ns, cache) `thenRn_`
- returnRn locals
+newExternalName :: NameCache -> Module -> OccName -> SrcLoc
+ -> (NameCache,Name)
+-- Allocate a new unique, manufacture a new External Name,
+-- put it in the cache, and return the two
+newExternalName name_supply mod occ loc
+ = (new_name_supply, name)
+ where
+ (us', us1) = splitUniqSupply (nsUniqs name_supply)
+ uniq = uniqFromSupply us1
+ name = mkExternalName uniq mod occ loc
+ new_cache = extend_name_cache (nsNames name_supply) mod occ name
+ new_name_supply = name_supply {nsUniqs = us', nsNames = new_cache}
+
+lookupOrigNameCache :: OrigNameCache -> Module -> OccName -> Maybe Name
+lookupOrigNameCache nc mod occ
+ = case lookupModuleEnv nc mod of
+ Nothing -> Nothing
+ Just (_, occ_env) -> lookupFM occ_env occ
+
+extendOrigNameCache :: OrigNameCache -> Name -> OrigNameCache
+extendOrigNameCache nc name
+ = extend_name_cache nc (nameModule name) (nameOccName name) name
+
+extend_name_cache :: OrigNameCache -> Module -> OccName -> Name -> OrigNameCache
+extend_name_cache nc mod occ name
+ = extendModuleEnv_C combine nc mod (mod, unitFM occ name)
+ where
+ combine (mod, occ_env) _ = (mod, addToFM occ_env occ name)
+\end{code}
--- mkUnboundName makes a place-holder Name; it shouldn't be looked at except possibly
--- during compiler debugging.
-mkUnboundName :: RdrName -> Name
-mkUnboundName rdr_name = mkLocalName unboundKey (rdrNameOcc rdr_name) noSrcLoc
+%*********************************************************
+%* *
+\subsection{Looking up names}
+%* *
+%*********************************************************
-isUnboundName :: Name -> Bool
-isUnboundName name = uniqueOf name == unboundKey
-\end{code}
+Looking up a name in the RnEnv.
\begin{code}
-bindLocatedLocalsRn :: (PprStyle -> Doc) -- Documentation string for error message
- -> [(RdrName,SrcLoc)]
- -> ([Name] -> RnMS s a)
- -> RnMS s a
-bindLocatedLocalsRn doc_str rdr_names_w_loc enclosed_scope
- = checkDupOrQualNames doc_str rdr_names_w_loc `thenRn_`
-
- getNameEnv `thenRn` \ name_env ->
- (if opt_WarnNameShadowing
- then
- mapRn (check_shadow name_env) rdr_names_w_loc
- else
- returnRn []
- ) `thenRn_`
-
- newLocalNames rdr_names_w_loc `thenRn` \ names ->
+lookupBndrRn rdr_name
+ = getLocalRdrEnv `thenM` \ local_env ->
+ case lookupRdrEnv local_env rdr_name of
+ Just name -> returnM name
+ Nothing -> lookupTopBndrRn rdr_name
+
+lookupTopBndrRn rdr_name
+-- Look up a top-level local binder. We may be looking up an unqualified 'f',
+-- and there may be several imported 'f's too, which must not confuse us.
+-- 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.
+
+ = getModeRn `thenM` \ mode ->
+ case mode of
+ InterfaceMode mod ->
+ getSrcLocM `thenM` \ loc ->
+ newTopBinder mod rdr_name loc
+
+ other -> lookupTopSrcBndr rdr_name
+
+lookupTopSrcBndr :: RdrName -> TcRn m Name
+lookupTopSrcBndr rdr_name
+ = lookupTopSrcBndr_maybe rdr_name `thenM` \ maybe_name ->
+ case maybe_name of
+ Just name -> returnM name
+ Nothing -> unboundName rdr_name
+
+
+lookupTopSrcBndr_maybe :: RdrName -> TcRn m (Maybe Name)
+-- Look up a source-code binder
+
+-- Ignores imported names; 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
+
+lookupTopSrcBndr_maybe rdr_name
+ | Just name <- isExact_maybe rdr_name
+ -- This is here just to catch the PrelBase defn of (say) [] and similar
+ -- The parser reads the special syntax and returns an Exact RdrName
+ -- But the global_env contains only Qual RdrNames, so we won't
+ -- find it there; instead just get the name via the Orig route
+ --
+ -- 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 (moduleName mod == moduleName (nameModule name))
+ (badOrigBinding rdr_name) `thenM_`
+ returnM (Just name)
+
+ | otherwise
+ = getGlobalRdrEnv `thenM` \ global_env ->
+ case lookupRdrEnv global_env rdr_name of
+ Nothing -> returnM Nothing
+ Just gres -> case [gre_name gre | gre <- gres, isLocalGRE gre] of
+ [] -> returnM Nothing
+ (n:ns) -> returnM (Just n)
+
+
+-- 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
+lookupSigOccRn :: RdrName -> RnM Name
+lookupSigOccRn = lookupBndrRn
+
+-- lookupInstDeclBndr is used for the binders in an
+-- instance declaration. Here we use the class name to
+-- disambiguate.
+
+lookupInstDeclBndr :: Name -> RdrName -> RnM Name
+ -- We use the selector name as the binder
+lookupInstDeclBndr cls_name rdr_name
+ | isUnqual rdr_name
+ = -- Find all the things the class op name maps to
+ -- and pick the one with the right parent name
+ getGblEnv `thenM` \ gbl_env ->
let
- new_name_env = addListToFM name_env (map fst rdr_names_w_loc `zip` names)
+ avail_env = imp_env (tcg_imports gbl_env)
in
- setNameEnv new_name_env (enclosed_scope names)
- where
- check_shadow name_env (rdr_name,loc)
- = case lookupFM name_env rdr_name of
- Nothing -> returnRn ()
- Just name -> pushSrcLocRn loc $
- addWarnRn (shadowedNameWarn rdr_name)
-
-bindLocalsRn doc_str rdr_names enclosed_scope
- = getSrcLocRn `thenRn` \ loc ->
- bindLocatedLocalsRn (\_ -> text doc_str)
- (rdr_names `zip` repeat loc)
- enclosed_scope
+ case lookupAvailEnv avail_env cls_name of
+ Nothing ->
+ -- If the class itself isn't in scope, then cls_name will
+ -- be unboundName, and there'll already be an error for
+ -- that in the error list. Example:
+ -- e.g. import Prelude hiding( Ord )
+ -- instance Ord T where ...
+ -- The program is wrong, but that should not cause a crash.
+ returnM (mkUnboundName rdr_name)
+
+ Just (AvailTC _ ns) -> case [n | n <- ns, nameOccName n == occ] of
+ (n:ns)-> ASSERT( null ns ) returnM n
+ [] -> unboundName rdr_name
+
+ other -> pprPanic "lookupInstDeclBndr" (ppr cls_name)
+
+
+ | otherwise -- Occurs in derived instances, where we just
+ -- refer directly to the right method, and avail_env
+ -- isn't available
+ = ASSERT2( not (isQual rdr_name), ppr rdr_name )
+ -- NB: qualified names are rejected by the parser
+ lookupOrigName rdr_name
-bindTyVarsRn 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 (zipWith replaceTyVarName tyvar_names names)
+ where
+ occ = rdrNameOcc rdr_name
+
+lookupSysBndr :: RdrName -> RnM Name
+-- Used for the 'system binders' in a data type or class declaration
+-- Do *not* look up in the RdrEnv; these system binders are never in scope
+-- Instead, get the module from the monad... but remember that
+-- where the module is depends on whether we are renaming source or
+-- interface file stuff
+lookupSysBndr rdr_name
+ = getSrcLocM `thenM` \ loc ->
+ getModeRn `thenM` \ mode ->
+ case mode of
+ InterfaceMode mod -> newTopBinder mod rdr_name loc
+ other -> getModule `thenM` \ mod ->
+ newTopBinder mod rdr_name loc
+
+-- lookupOccRn looks up an occurrence of a RdrName
+lookupOccRn :: RdrName -> RnM Name
+lookupOccRn rdr_name
+ = getLocalRdrEnv `thenM` \ local_env ->
+ case lookupRdrEnv local_env rdr_name of
+ Just name -> returnM name
+ Nothing -> lookupGlobalOccRn rdr_name
- -- Works in any variant of the renamer monad
-checkDupOrQualNames, checkDupNames :: (PprStyle -> Doc)
- -> [(RdrName, SrcLoc)]
- -> RnM s d ()
+-- 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
-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
- where
- quals = filter (isQual.fst) rdr_names_w_loc
-
-checkDupNames doc_str rdr_names_w_loc
- = -- Check for dupicated names in a binding group
- mapRn (dupNamesErr doc_str) dups `thenRn_`
- returnRn ()
- where
- (_, dups) = removeDups (\(n1,l1) (n2,l2) -> n1 `cmp` n2) rdr_names_w_loc
+lookupGlobalOccRn rdr_name
+ = getModeRn `thenM` \ mode ->
+ case mode of
+ InterfaceMode mod -> lookupIfaceName mod rdr_name
+ SourceMode -> lookupSrcName rdr_name
+
+ CmdLineMode
+ | not (isQual rdr_name) ->
+ lookupSrcName rdr_name
+
+ -- 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.
+ --
+ -- First look up the name in the normal environment. If
+ -- it isn't there, we manufacture a new occurrence of an
+ -- original name.
+ | otherwise ->
+ lookupSrcName_maybe rdr_name `thenM` \ mb_name ->
+ case mb_name of
+ Just name -> returnM name
+ Nothing -> lookupQualifiedName rdr_name
+
+-- 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 -> TcRn m Name
+lookupQualifiedName rdr_name
+ = let
+ mod = rdrNameModule rdr_name
+ occ = rdrNameOcc rdr_name
+ in
+ loadInterface (ppr rdr_name) mod (ImportByUser False) `thenM` \ iface ->
+ case [ name | (_,avails) <- mi_exports iface,
+ avail <- avails,
+ name <- availNames avail,
+ nameOccName name == occ ] of
+ (n:ns) -> ASSERT (null ns) returnM n
+ _ -> unboundName rdr_name
+
+lookupSrcName :: RdrName -> TcRn m Name
+lookupSrcName rdr_name
+ = lookupSrcName_maybe rdr_name `thenM` \ mb_name ->
+ case mb_name of
+ Nothing -> unboundName rdr_name
+ Just name -> returnM name
+
+lookupSrcName_maybe :: RdrName -> TcRn m (Maybe Name)
+lookupSrcName_maybe rdr_name
+ | Just name <- isExact_maybe rdr_name -- Can occur in source code too
+ = returnM (Just name)
+
+ | isOrig rdr_name -- An original name
+ = newGlobalNameFromRdrName rdr_name `thenM` \ name ->
+ returnM (Just name)
+
+ | otherwise
+ = lookupGRE rdr_name `thenM` \ mb_gre ->
+ case mb_gre of
+ Nothing -> returnM Nothing
+ Just gre -> returnM (Just (gre_name gre))
+
+lookupGRE :: RdrName -> TcRn m (Maybe GlobalRdrElt)
+lookupGRE rdr_name
+ = getGlobalRdrEnv `thenM` \ global_env ->
+ case lookupRdrEnv global_env rdr_name of
+ Just [gre] -> case gre_deprec gre of
+ Nothing -> returnM (Just gre)
+ Just _ -> warnDeprec gre `thenM_`
+ returnM (Just gre)
+ Just stuff@(gre : _) -> addNameClashErrRn rdr_name stuff `thenM_`
+ returnM (Just gre)
+ Nothing -> return Nothing
+
+lookupIfaceName :: Module -> RdrName -> TcRn m Name
+ -- An Unqual is allowed; interface files contain
+ -- unqualified names for locally-defined things, such as
+ -- constructors of a data type.
+lookupIfaceName mod rdr_name
+ | isUnqual rdr_name = newGlobalName mod (rdrNameOcc rdr_name) importedSrcLoc
+ | otherwise = lookupOrigName rdr_name
+
+lookupOrigName :: RdrName -> TcRn m Name
+ -- Just for original or exact names
+lookupOrigName rdr_name
+ | Just n <- isExact_maybe rdr_name
+ -- This happens in derived code, which we
+ -- rename in InterfaceMode
+ = returnM n
+
+ | otherwise -- Usually Orig, but can be a Qual when
+ -- we are reading a .hi-boot file
+ = newGlobalNameFromRdrName rdr_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
+dataTcOccs rdr_name
+ | isDataOcc occ = [rdr_name, rdr_name_tc]
+ | otherwise = [rdr_name]
+ where
+ occ = rdrNameOcc rdr_name
+ rdr_name_tc = setRdrNameSpace rdr_name tcName
\end{code}
+\begin{code}
+unboundName rdr_name = addErr (unknownNameErr rdr_name) `thenM_`
+ returnM (mkUnboundName rdr_name)
+\end{code}
%*********************************************************
%* *
-\subsection{Looking up names}
+ Fixities
%* *
%*********************************************************
-Looking up a name in the RnEnv.
-
\begin{code}
-lookupRn :: NameEnv -> RdrName -> RnMS s Name
-lookupRn name_env rdr_name
- = case lookupFM name_env rdr_name of
-
- -- Found it!
- Just name -> returnRn name
-
- -- Not found
- 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 _ ->
- case rdr_name of
-
- Qual mod_name occ -> newGlobalName mod_name occ
-
- -- An Unqual is allowed; interface files contain
- -- unqualified names for locally-defined things, such as
- -- constructors of a data type.
- Unqual occ -> getModuleRn `thenRn ` \ mod_name ->
- newGlobalName mod_name occ
+--------------------------------
+bindLocalFixities :: [RdrNameFixitySig] -> 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 v fix src_loc)
+ = addSrcLoc src_loc $
+ lookupSigOccRn v `thenM` \ new_v ->
+ returnM (new_v, FixitySig new_v fix src_loc)
+\end{code}
+--------------------------------
+lookupFixity is a bit strange.
-lookupBndrRn rdr_name
- = getNameEnv `thenRn` \ name_env ->
- lookupRn name_env 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 s Name
-lookupOccRn rdr_name
- = getNameEnv `thenRn` \ name_env ->
- lookupRn name_env rdr_name `thenRn` \ name ->
- addOccurrenceName name
+* Nested local fixity decls are put in the local fixity env, which we
+ find with getFixtyEnv
--- lookupGlobalOccRn is like lookupOccRn, except that it looks in the global
--- environment. It's used for record field names only.
-lookupGlobalOccRn :: RdrName -> RnMS s Name
-lookupGlobalOccRn rdr_name
- = getGlobalNameEnv `thenRn` \ name_env ->
- lookupRn name_env rdr_name `thenRn` \ name ->
- addOccurrenceName name
-
-
-
--- lookupImplicitOccRn takes an RdrName representing an *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).
---
--- 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.
-
-lookupImplicitOccRn :: RdrName -> RnMS s Name
-lookupImplicitOccRn (Qual mod occ)
- = newGlobalName mod occ `thenRn` \ name ->
- addOccurrenceName name
-
-addImplicitOccRn :: Name -> RnMS s Name
-addImplicitOccRn name = addOccurrenceName name
-
-addImplicitOccsRn :: [Name] -> RnMS s ()
-addImplicitOccsRn names = addOccurrenceNames names
-
-listType_RDR = qual (modAndOcc listType_name)
-tupleType_RDR n = qual (modAndOcc (tupleType_name n))
-
-charType_name = getName charTyCon
-listType_name = getName listTyCon
-tupleType_name n = getName (tupleTyCon n)
-\end{code}
+* Imported fixities are found in the HIT or PIT
+
+* 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}
-lookupFixity :: RdrName -> RnMS s Fixity
-lookupFixity rdr_name
- = getFixityEnv `thenRn` \ fixity_env ->
- returnRn (lookupFixityEnv fixity_env rdr_name)
+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 ->
+ 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.
+ loadInterface doc name_mod ImportBySystem `thenM` \ iface ->
+ returnM (lookupFixity (mi_fixities iface) name)
+ where
+ doc = ptext SLIT("Checking fixity for") <+> ppr name
+ name_mod = moduleName (nameModule name)
\end{code}
+%*********************************************************
+%* *
+\subsection{Implicit free vars and sugar names}
+%* *
+%*********************************************************
+
+@getXImplicitFVs@ forces the renamer to slurp in some things which aren't
+mentioned explicitly, but which might be needed by the type checker.
+
+\begin{code}
+implicitStmtFVs source_fvs -- Compiling a statement
+ = stmt_fvs `plusFV` implicitModuleFVs source_fvs
+ where
+ stmt_fvs = mkFVs [printName, bindIOName, thenIOName, returnIOName, failIOName]
+ -- These are all needed implicitly when compiling a statement
+ -- See TcModule.tc_stmts
+
+implicitModuleFVs source_fvs
+ = mkTemplateHaskellFVs source_fvs `plusFV`
+ namesNeededForFlattening `plusFV`
+ ubiquitousNames
+
+
+thProxyName :: NameSet
+mkTemplateHaskellFVs :: NameSet -> NameSet
+ -- This is a bit of a hack. When we see the Template-Haskell construct
+ -- [| expr |]
+ -- we are going to need lots of the ``smart constructors'' defined in
+ -- the main Template Haskell data type module. Rather than treat them
+ -- all as free vars at every occurrence site, we just make the Q type
+ -- consructor a free var.... and then use that here to haul in the others
+
+#ifdef GHCI
+--------------- Template Haskell enabled --------------
+thProxyName = unitFV qTyConName
+
+mkTemplateHaskellFVs source_fvs
+ | qTyConName `elemNameSet` source_fvs = templateHaskellNames
+ | otherwise = emptyFVs
+
+#else
+--------------- Template Haskell disabled --------------
+
+thProxyName = emptyFVs
+mkTemplateHaskellFVs source_fvs = emptyFVs
+#endif
+--------------------------------------------------------
+
+-- ubiquitous_names are loaded regardless, because
+-- they are needed in virtually every program
+ubiquitousNames
+ = mkFVs [unpackCStringName, unpackCStringFoldrName,
+ unpackCStringUtf8Name, eqStringName,
+ -- Virtually every program has error messages in it somewhere
+ getName unitTyCon, funTyConName, boolTyConName, intTyConName]
+ -- Add occurrences for very frequently used types.
+ -- (e.g. we don't want to be bothered with making
+ -- funTyCon a free var at every function application!)
+\end{code}
%************************************************************************
%* *
-\subsection{Envt utility functions}
+\subsection{Re-bindable desugaring names}
%* *
%************************************************************************
-=============== RnEnv ================
+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}
-plusRnEnv (RnEnv n1 f1) (RnEnv n2 f2)
- = plusNameEnvRn n1 n2 `thenRn` \ n ->
- plusFixityEnvRn f1 f2 `thenRn` \ f ->
- returnRn (RnEnv n f)
+lookupSyntaxName :: Name -- The standard name
+ -> RnM (Name, FreeVars) -- Possibly a non-standard name
+lookupSyntaxName std_name
+ = getModeRn `thenM` \ mode ->
+ if isInterfaceMode mode then
+ returnM (std_name, unitFV std_name)
+ -- Happens for 'derived' code
+ -- where we don't want to rebind
+ else
+
+ doptM Opt_NoImplicitPrelude `thenM` \ no_prelude ->
+ if not no_prelude then
+ returnM (std_name, unitFV std_name) -- Normal case
+
+ else
+ -- Get the similarly named thing from the local environment
+ lookupOccRn (mkRdrUnqual (nameOccName std_name)) `thenM` \ usr_name ->
+ returnM (usr_name, mkFVs [usr_name, std_name])
\end{code}
-=============== NameEnv ================
+
+%*********************************************************
+%* *
+\subsection{Binding}
+%* *
+%*********************************************************
+
\begin{code}
-plusNameEnvRn :: NameEnv -> NameEnv -> RnM s d NameEnv
-plusNameEnvRn env1 env2
- = mapRn (addErrRn.nameClashErr) (conflictsFM conflicting_name env1 env2) `thenRn_`
- returnRn (env1 `plusFM` env2)
-
-addOneToNameEnv :: NameEnv -> RdrName -> Name -> RnM s d NameEnv
-addOneToNameEnv env rdr_name name
- = case lookupFM env rdr_name of
- Just name2 | conflicting_name name name2
- -> addErrRn (nameClashErr (rdr_name, (name, name2))) `thenRn_`
- returnRn env
-
- Nothing -> returnRn (addToFM env rdr_name name)
-
-conflicting_name n1 n2 = (n1 /= n2) || (isLocallyDefinedName n1 && isLocallyDefinedName n2)
- -- We complain of a conflict if one RdrName maps to two different Names,
- -- OR if one RdrName maps to the same *locally-defined* Name. The latter
- -- case is to catch two separate, local definitions of the same thing.
- --
- -- 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.
+newLocalsRn :: [(RdrName,SrcLoc)]
+ -> RnM [Name]
+newLocalsRn rdr_names_w_loc
+ = newUniqueSupply `thenM` \ us ->
+ let
+ uniqs = uniqsFromSupply us
+ names = [ mkInternalName uniq (rdrNameOcc rdr_name) loc
+ | ((rdr_name,loc), uniq) <- rdr_names_w_loc `zip` uniqs
+ ]
+ in
+ returnM names
-lookupNameEnv :: NameEnv -> RdrName -> Maybe Name
-lookupNameEnv = lookupFM
-delOneFromNameEnv :: NameEnv -> RdrName -> NameEnv
-delOneFromNameEnv env rdr_name = delFromFM env rdr_name
-\end{code}
+bindLocatedLocalsRn :: SDoc -- Documentation string for error message
+ -> [(RdrName,SrcLoc)]
+ -> ([Name] -> RnM a)
+ -> RnM a
+bindLocatedLocalsRn doc_str rdr_names_w_loc enclosed_scope
+ = getModeRn `thenM` \ mode ->
+ getLocalRdrEnv `thenM` \ local_env ->
+ getGlobalRdrEnv `thenM` \ global_env ->
-=============== FixityEnv ================
-\begin{code}
-plusFixityEnvRn f1 f2
- = mapRn (addErrRn.fixityClashErr) (conflictsFM bad_fix f1 f2) `thenRn_`
- returnRn (f1 `plusFM` f2)
+ -- Check for duplicate names
+ checkDupOrQualNames doc_str rdr_names_w_loc `thenM_`
-addOneToFixityEnv env rdr_name fixity = addToFM env rdr_name fixity
+ -- Warn about shadowing, but only in source modules
+ let
+ check_shadow (rdr_name,loc)
+ | rdr_name `elemRdrEnv` local_env
+ || rdr_name `elemRdrEnv` global_env
+ = addSrcLoc loc $ addWarn (shadowedNameWarn rdr_name)
+ | otherwise
+ = returnM ()
+ in
-lookupFixityEnv env rdr_name
- = case lookupFM env rdr_name of
- Just (fixity,_) -> fixity
- Nothing -> Fixity 9 InfixL -- Default case
+ (case mode of
+ SourceMode -> ifOptM Opt_WarnNameShadowing $
+ mappM_ check_shadow rdr_names_w_loc
+ other -> returnM ()
+ ) `thenM_`
-bad_fix :: (Fixity, Provenance) -> (Fixity, Provenance) -> Bool
-bad_fix (f1,_) (f2,_) = f1 /= f2
+ newLocalsRn rdr_names_w_loc `thenM` \ names ->
+ let
+ new_local_env = addListToRdrEnv local_env (map fst rdr_names_w_loc `zip` names)
+ in
+ setLocalRdrEnv new_local_env (enclosed_scope names)
+
+bindCoreLocalRn :: RdrName -> (Name -> RnM a) -> RnM a
+ -- 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
+bindCoreLocalRn rdr_name enclosed_scope
+ = getSrcLocM `thenM` \ loc ->
+ getLocalRdrEnv `thenM` \ name_env ->
+ newUnique `thenM` \ uniq ->
+ let
+ name = mkInternalName uniq (rdrNameOcc rdr_name) loc
+ new_name_env = extendRdrEnv name_env rdr_name name
+ in
+ setLocalRdrEnv new_name_env (enclosed_scope name)
+
+bindCoreLocalsRn [] thing_inside = thing_inside []
+bindCoreLocalsRn (b:bs) thing_inside = bindCoreLocalRn b $ \ name' ->
+ bindCoreLocalsRn bs $ \ names' ->
+ thing_inside (name':names')
+
+bindLocalNames names enclosed_scope
+ = getLocalRdrEnv `thenM` \ name_env ->
+ setLocalRdrEnv (extendLocalRdrEnv name_env names)
+ enclosed_scope
+
+bindLocalNamesFV names enclosed_scope
+ = bindLocalNames names $
+ enclosed_scope `thenM` \ (thing, fvs) ->
+ returnM (thing, delListFromNameSet fvs names)
+
+
+-------------------------------------
+bindLocalRn doc rdr_name enclosed_scope
+ = getSrcLocM `thenM` \ loc ->
+ bindLocatedLocalsRn doc [(rdr_name,loc)] $ \ (n:ns) ->
+ ASSERT( null ns )
+ enclosed_scope n
+
+bindLocalsRn doc rdr_names enclosed_scope
+ = getSrcLocM `thenM` \ loc ->
+ bindLocatedLocalsRn doc
+ (rdr_names `zip` repeat loc)
+ enclosed_scope
-pprFixityProvenance :: PprStyle -> (Fixity,Provenance) -> Doc
-pprFixityProvenance sty (fixity, prov) = pprProvenance sty prov
-\end{code}
+ -- 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 `thenM` \ (thing, fvs) ->
+ returnM (thing, delListFromNameSet fvs names)
+
+-------------------------------------
+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)
+
+bindTyVarsRn :: SDoc -> [HsTyVarBndr RdrName]
+ -> ([HsTyVarBndr Name] -> RnM a)
+ -> RnM a
+bindTyVarsRn doc_str tyvar_names enclosed_scope
+ = getSrcLocM `thenM` \ loc ->
+ let
+ located_tyvars = [(hsTyVarName tv, loc) | tv <- tyvar_names]
+ in
+ bindLocatedLocalsRn doc_str located_tyvars $ \ names ->
+ enclosed_scope (zipWith replaceTyVarName tyvar_names names)
+bindPatSigTyVars :: [RdrNameHsType]
+ -> RnM (a, FreeVars)
+ -> RnM (a, FreeVars)
+ -- Find the type variables in the pattern type
+ -- signatures that must be brought into scope
+bindPatSigTyVars tys enclosed_scope
+ = getLocalRdrEnv `thenM` \ name_env ->
+ getSrcLocM `thenM` \ loc ->
+ let
+ forall_tyvars = nub [ tv | ty <- tys,
+ tv <- extractHsTyRdrTyVars ty,
+ not (tv `elemFM` name_env)
+ ]
+ -- The 'nub' is important. For example:
+ -- f (x :: t) (y :: t) = ....
+ -- We don't want to complain about binding t twice!
+
+ located_tyvars = [(tv, loc) | tv <- forall_tyvars]
+ doc_sig = text "In a pattern type-signature"
+ in
+ bindLocatedLocalsRn doc_sig located_tyvars $ \ names ->
+ enclosed_scope `thenM` \ (thing, fvs) ->
+ returnM (thing, delListFromNameSet fvs names)
-=============== Avails ================
-\begin{code}
-mkExportAvails :: Bool -> Module -> [AvailInfo] -> ExportAvails
-mkExportAvails unqualified_import mod_name avails
- = (mod_avail_env, entity_avail_env)
+
+-------------------------------------
+checkDupOrQualNames, checkDupNames :: SDoc
+ -> [(RdrName, SrcLoc)]
+ -> TcRn m ()
+ -- Works in any variant of the renamer monad
+
+checkDupOrQualNames doc_str rdr_names_w_loc
+ = -- Qualified names in patterns are now rejected by the parser
+ -- but I'm not 100% certain that it finds all cases, so I've left
+ -- this check in for now. Should go eventually.
+ -- Hmm. Sooner rather than later.. data type decls
+-- mappM_ (qualNameErr doc_str) quals `thenM_`
+ checkDupNames doc_str rdr_names_w_loc
where
- -- The "module M" syntax only applies to *unqualified* imports (1.4 Report, Section 5.1.1)
- mod_avail_env | unqualified_import = unitFM mod_name avails
- | otherwise = emptyFM
-
- entity_avail_env = listToUFM [ (name,avail) | avail <- avails,
- name <- availEntityNames avail]
-
-plusExportAvails :: ExportAvails -> ExportAvails -> ExportAvails
-plusExportAvails (m1, e1) (m2, e2)
- = (plusFM_C (++) m1 m2, plusUFM_C plusAvail e1 e2)
+ quals = filter (isQual . fst) rdr_names_w_loc
+
+checkDupNames doc_str rdr_names_w_loc
+ = -- Check for duplicated names in a binding group
+ mappM_ (dupNamesErr doc_str) dups
+ where
+ (_, dups) = removeDups (\(n1,l1) (n2,l2) -> n1 `compare` n2) rdr_names_w_loc
\end{code}
-=============== AvailInfo ================
-\begin{code}
-plusAvail (Avail n1) (Avail n2) = Avail n1
-plusAvail (AvailTC n1 ns1) (AvailTC n2 ns2) = AvailTC n1 (nub (ns1 ++ ns2))
-plusAvail a NotAvailable = a
-plusAvail NotAvailable a = a
--- Added SOF 4/97
-#ifdef DEBUG
-plusAvail a1 a2 = panic ("RnEnv.plusAvail " ++ (show (hsep [pprAvail PprDebug a1,pprAvail PprDebug a2])))
-#endif
+%************************************************************************
+%* *
+\subsection{GlobalRdrEnv}
+%* *
+%************************************************************************
-addAvailToNameSet :: NameSet -> AvailInfo -> NameSet
-addAvailToNameSet names avail = addListToNameSet names (availNames avail)
-
-availsToNameSet :: [AvailInfo] -> NameSet
-availsToNameSet avails = foldl addAvailToNameSet emptyNameSet avails
-
-availName :: AvailInfo -> Name
-availName (Avail n) = n
-availName (AvailTC n _) = n
-
-availNames :: AvailInfo -> [Name]
-availNames NotAvailable = []
-availNames (Avail n) = [n]
-availNames (AvailTC n ns) = ns
-
--- availEntityNames is used to extract the names that can appear on their own in
--- an export or import list. For class decls, class methods can appear on their
--- own, thus import A( op )
--- but constructors cannot; thus
--- import B( T )
--- means import type T from B, not constructor T.
-
-availEntityNames :: AvailInfo -> [Name]
-availEntityNames NotAvailable = []
-availEntityNames (Avail n) = [n]
-availEntityNames (AvailTC n ns) = n : filter (isVarOcc . nameOccName) ns
-
-filterAvail :: RdrNameIE -- Wanted
- -> AvailInfo -- Available
- -> AvailInfo -- Resulting available;
- -- NotAvailable if wanted stuff isn't there
-
-filterAvail ie@(IEThingWith want wants) avail@(AvailTC n ns)
- | sub_names_ok = AvailTC n (filter is_wanted ns)
- | otherwise = pprTrace "filterAvail" (hsep [ppr PprDebug ie, pprAvail PprDebug avail]) $
- NotAvailable
+\begin{code}
+mkGlobalRdrEnv :: ModuleName -- Imported module (after doing the "as M" name change)
+ -> Bool -- True <=> want unqualified import
+ -> (Name -> Provenance)
+ -> Avails -- Whats imported
+ -> Deprecations
+ -> GlobalRdrEnv
+
+mkGlobalRdrEnv this_mod unqual_imp mk_provenance avails deprecs
+ = gbl_env2
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)
- | n `elem` ns = AvailTC n [n]
+ -- Make the name environment. We're talking about a
+ -- single module here, so there must be no name clashes.
+ -- In practice there only ever will be if it's the module
+ -- being compiled.
+
+ -- Add qualified names for the things that are available
+ -- (Qualified names are always imported)
+ gbl_env1 = foldl add_avail emptyRdrEnv avails
+
+ -- Add unqualified names
+ gbl_env2 | unqual_imp = foldl add_unqual gbl_env1 (rdrEnvToList gbl_env1)
+ | otherwise = gbl_env1
+
+ add_unqual env (qual_name, elts)
+ = foldl add_one env elts
+ where
+ add_one env elt = addOneToGlobalRdrEnv env unqual_name elt
+ unqual_name = unqualifyRdrName qual_name
+ -- The qualified import should only have added one
+ -- binding for each qualified name! But if there's an error in
+ -- the module (multiple bindings for the same name) we may get
+ -- duplicates. So the simple thing is to do the fold.
+
+ add_avail :: GlobalRdrEnv -> AvailInfo -> GlobalRdrEnv
+ add_avail env avail = foldl (add_name (availName avail)) env (availNames avail)
+
+ add_name parent env name -- Add qualified name only
+ = addOneToGlobalRdrEnv env (mkRdrQual this_mod occ) elt
+ where
+ occ = nameOccName name
+ elt = GRE {gre_name = name,
+ gre_parent = if name == parent
+ then Nothing
+ else Just parent,
+ gre_prov = mk_provenance name,
+ gre_deprec = lookupDeprec deprecs name}
+
+\end{code}
-filterAvail (IEThingAbs _) avail@(Avail n) = avail -- Type synonyms
+\begin{code}
+plusGlobalRdrEnv :: GlobalRdrEnv -> GlobalRdrEnv -> GlobalRdrEnv
+plusGlobalRdrEnv env1 env2 = plusFM_C combine_globals env1 env2
-filterAvail (IEVar _) avail@(Avail n) = avail
-filterAvail (IEVar v) avail@(AvailTC n ns) = 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
+addOneToGlobalRdrEnv :: GlobalRdrEnv -> RdrName -> GlobalRdrElt -> GlobalRdrEnv
+addOneToGlobalRdrEnv env rdr_name name = addToFM_C combine_globals env rdr_name [name]
-filterAvail (IEThingAll _) avail@(AvailTC _ _) = avail
+delOneFromGlobalRdrEnv :: GlobalRdrEnv -> RdrName -> GlobalRdrEnv
+delOneFromGlobalRdrEnv env rdr_name = delFromFM env rdr_name
-filterAvail ie avail = NotAvailable
+combine_globals :: [GlobalRdrElt] -- Old
+ -> [GlobalRdrElt] -- New
+ -> [GlobalRdrElt]
+combine_globals ns_old ns_new -- ns_new is often short
+ = foldr add ns_old ns_new
+ where
+ add n ns | any (is_duplicate n) ns_old = map (choose n) ns -- Eliminate duplicates
+ | otherwise = n:ns
+ choose n m | n `beats` m = n
+ | otherwise = m
--- In interfaces, pprAvail gets given the OccName of the "host" thing
-pprAvail PprInterface avail = ppr_avail (pprOccName PprInterface . nameOccName) avail
-pprAvail sty avail = ppr_avail (ppr sty) avail
+ g1 `beats` g2 = gre_name g1 == gre_name g2 &&
+ gre_prov g1 `hasBetterProv` gre_prov g2
-ppr_avail pp_name NotAvailable = ptext SLIT("NotAvailable")
-ppr_avail pp_name (AvailTC n ns) = hsep [
- pp_name n,
- parens $ hsep $ punctuate comma $
- map pp_name ns
- ]
-ppr_avail pp_name (Avail n) = pp_name n
+ is_duplicate :: GlobalRdrElt -> GlobalRdrElt -> Bool
+ is_duplicate g1 g2 | isLocalGRE g1 && isLocalGRE g2 = False
+ is_duplicate g1 g2 = gre_name g1 == gre_name g2
\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 do} 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.
%************************************************************************
%* *
-\subsection{Finite map utilities}
+\subsection{Free variable manipulation}
%* *
%************************************************************************
-
-Generally useful function on finite maps to check for overlap.
-
\begin{code}
-conflictsFM :: Ord a
- => (b->b->Bool) -- False <=> no conflict; you can pick either
- -> FiniteMap a b -> FiniteMap a b
- -> [(a,(b,b))]
-conflictsFM bad fm1 fm2
- = filter (\(a,(b1,b2)) -> bad b1 b2)
- (fmToList (intersectFM_C (\b1 b2 -> (b1,b2)) fm1 fm2))
-
-conflictFM :: Ord a
- => (b->b->Bool)
- -> FiniteMap a b -> a -> b
- -> [(a,(b,b))]
-conflictFM bad fm key elt
- = case lookupFM fm key of
- Just elt' | bad elt elt' -> [(key,(elt,elt'))]
- other -> []
+-- A useful utility
+mapFvRn f xs = mappM f xs `thenM` \ stuff ->
+ let
+ (ys, fvs_s) = unzip stuff
+ in
+ returnM (ys, plusFVs fvs_s)
\end{code}
%* *
%************************************************************************
+\begin{code}
+warnUnusedModules :: [ModuleName] -> TcRn m ()
+warnUnusedModules mods
+ = ifOptM Opt_WarnUnusedImports (mappM_ (addWarn . unused_mod) mods)
+ where
+ 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))]
+
+warnUnusedImports, warnUnusedTopBinds :: [GlobalRdrElt] -> TcRn m ()
+warnUnusedImports gres = ifOptM Opt_WarnUnusedImports (warnUnusedGREs gres)
+warnUnusedTopBinds gres = ifOptM Opt_WarnUnusedBinds (warnUnusedGREs gres)
+
+warnUnusedLocalBinds, warnUnusedMatches :: [Name] -> TcRn m ()
+warnUnusedLocalBinds names = ifOptM Opt_WarnUnusedBinds (warnUnusedLocals names)
+warnUnusedMatches names = ifOptM Opt_WarnUnusedMatches (warnUnusedLocals names)
+
+-------------------------
+-- Helpers
+warnUnusedGREs gres = warnUnusedBinds [(n,p) | GRE {gre_name = n, gre_prov = p} <- gres]
+warnUnusedLocals names = warnUnusedBinds [(n,LocalDef) | n<-names]
+
+warnUnusedBinds :: [(Name,Provenance)] -> TcRn m ()
+warnUnusedBinds names
+ = mappM_ warnUnusedGroup groups
+ where
+ -- Group by provenance
+ groups = equivClasses cmp (filter reportable names)
+ (_,prov1) `cmp` (_,prov2) = prov1 `compare` prov2
+
+
+ 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 "_".
+
+-------------------------
+
+warnUnusedGroup :: [(Name,Provenance)] -> TcRn m ()
+warnUnusedGroup names
+ = addSrcLoc def_loc $
+ addWarn $
+ sep [msg <> colon, nest 4 (fsep (punctuate comma (map (ppr.fst) names)))]
+ where
+ (name1, prov1) = head names
+ loc1 = getSrcLoc name1
+ (def_loc, msg) = case prov1 of
+ LocalDef -> (loc1, unused_msg)
+ NonLocalDef (UserImport mod loc _) -> (loc, imp_from mod)
+
+ unused_msg = text "Defined but not used"
+ imp_from mod = text "Imported from" <+> quotes (ppr mod) <+> text "but not used"
+\end{code}
\begin{code}
-nameClashErr (rdr_name, (name1,name2)) sty
- = hang (hsep [ptext SLIT("Conflicting definitions for:"), ppr sty rdr_name])
- 4 (vcat [pprNameProvenance sty name1,
- pprNameProvenance sty name2])
-
-fixityClashErr (rdr_name, (fp1,fp2)) sty
- = hang (hsep [ptext SLIT("Conflicting fixities for:"), ppr sty rdr_name])
- 4 (vcat [pprFixityProvenance sty fp1,
- pprFixityProvenance sty fp2])
-
-shadowedNameWarn shadow sty
- = hcat [ptext SLIT("This binding for"),
- ppr sty shadow,
+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 np1
+ msgs = [ptext SLIT(" or") <+> mk_ref np | np <- nps]
+ mk_ref gre = quotes (ppr (gre_name gre)) <> comma <+> pprNameProvenance gre
+
+shadowedNameWarn shadow
+ = hsep [ptext SLIT("This binding for"),
+ quotes (ppr shadow),
ptext SLIT("shadows an existing binding")]
-unknownNameErr name sty
- = sep [text flavour, ptext SLIT("not in scope:"), ppr sty name]
+unknownNameErr name
+ = sep [text flavour, ptext SLIT("not in scope:"), quotes (ppr name)]
where
flavour = occNameFlavour (rdrNameOcc name)
+badOrigBinding name
+ = ptext SLIT("Illegal binding of built-in syntax:") <+> ppr (rdrNameOcc name)
+ -- The rdrNameOcc is because we don't want to print Prelude.(,)
+
qualNameErr descriptor (name,loc)
- = pushSrcLocRn loc $
- addErrRn (\sty -> hsep [ ptext SLIT("Invalid use of qualified name"),
- ppr sty name,
- ptext SLIT("in"),
- descriptor sty])
+ = addSrcLoc loc $
+ addErr (vcat [ ptext SLIT("Invalid use of qualified name") <+> quotes (ppr name),
+ descriptor])
dupNamesErr descriptor ((name,loc) : dup_things)
- = pushSrcLocRn loc $
- addErrRn (\sty -> hsep [ptext SLIT("Conflicting definitions for"),
- ppr sty name,
- ptext SLIT("in"), descriptor sty])
+ = addSrcLoc loc $
+ addErr ((ptext SLIT("Conflicting definitions for") <+> quotes (ppr name))
+ $$
+ descriptor)
+
+noIfaceErr dflags mod_name boot_file files
+ = ptext SLIT("Could not find interface file for") <+> quotes (ppr mod_name)
+ $$ extra
+ where
+ extra
+ | verbosity dflags < 3 =
+ text "(use -v to see a list of the files searched for)"
+ | otherwise =
+ hang (ptext SLIT("locations searched:")) 4 (vcat (map text files))
+
+warnDeprec :: GlobalRdrElt -> TcRn m ()
+warnDeprec (GRE {gre_name = name, gre_deprec = Just txt})
+ = ifOptM Opt_WarnDeprecations $
+ addWarn (sep [ text (occNameFlavour (nameOccName name)) <+>
+ quotes (ppr name) <+> text "is deprecated:",
+ nest 4 (ppr txt) ])
\end{code}
projects / ghc-hetmet.git / blobdiff