import RdrName ( RdrName, rdrNameModule, rdrNameOcc, isQual, isUnqual,
mkRdrUnqual, qualifyRdrName
)
-import HsTypes ( getTyVarName, replaceTyVarName )
+import HsTypes ( hsTyVarName, hsTyVarNames, replaceTyVarName )
import RnMonad
import Name ( Name, Provenance(..), ExportFlag(..), NamedThing(..),
ImportReason(..), getSrcLoc,
- mkLocalName, mkImportedLocalName, mkGlobalName, isSystemName,
- nameOccName, setNameModule,
- pprOccName, isLocallyDefined, nameUnique, nameOccName,
- setNameProvenance, getNameProvenance, pprNameProvenance
+ mkLocalName, mkImportedLocalName, mkGlobalName, mkUnboundName,
+ mkIPName, isWiredInName, hasBetterProv,
+ nameOccName, setNameModule, nameModule,
+ pprOccName, isLocallyDefined, nameUnique,
+ setNameProvenance, getNameProvenance, pprNameProvenance,
+ extendNameEnv_C, plusNameEnv_C, nameEnvElts
)
import NameSet
import OccName ( OccName,
- mkDFunOcc,
+ mkDFunOcc, occNameUserString, occNameString,
occNameFlavour
)
-import TysWiredIn ( tupleTyCon, unboxedTupleTyCon, listTyCon )
+import TysWiredIn ( listTyCon )
import Type ( funTyCon )
-import Module ( ModuleName, mkThisModule, mkVanillaModule, moduleName )
-import TyCon ( TyCon )
+import Module ( ModuleName, mkThisModule, moduleName, mkVanillaModule, pprModuleName )
import FiniteMap
-import Unique ( Unique, Uniquable(..) )
-import UniqFM ( emptyUFM, listToUFM, plusUFM_C )
import UniqSupply
import SrcLoc ( SrcLoc, noSrcLoc )
import Outputable
-import Util ( removeDups, equivClasses, thenCmp )
+import Util ( removeDups, equivClasses, thenCmp, sortLt )
import List ( nub )
-import Maybes ( mapMaybe )
\end{code}
%*********************************************************
\begin{code}
-newImportedBinder :: Module -> RdrName -> RnM d Name
--- Make a new imported binder. It might be in the cache already,
--- but if so it will have a dopey provenance, so replace it.
-newImportedBinder mod rdr_name
- = ASSERT2( isUnqual rdr_name, ppr rdr_name )
-
- -- First check the cache
- getNameSupplyRn `thenRn` \ (us, inst_ns, cache) ->
+implicitImportProvenance = NonLocalDef ImplicitImport False
+
+newTopBinder :: Module -> OccName -> RnM d Name
+newTopBinder mod occ
+ = -- First check the cache
+ traceRn (text "newTopBinder" <+> ppr mod <+> ppr occ) `thenRn_`
+
+ getNameSupplyRn `thenRn` \ (us, inst_ns, cache, ipcache) ->
let
- occ = rdrNameOcc rdr_name
- key = (moduleName mod, occ)
+ key = (moduleName mod, occ)
in
case lookupFM cache key of
-
- -- A hit in the cache!
- -- Overwrite the thing in the cache with a Name whose Module and Provenance
- -- is correct. It might be in the cache arising from an *occurrence*,
- -- whereas we are now at the binding site.
- -- Similarly for known-key things.
- -- For example, GHCmain.lhs imports as SOURCE
- -- Main; but Main.main is a known-key thing.
- Just name -> getOmitQualFn `thenRn` \ omit_fn ->
- let
- new_name = setNameProvenance (setNameModule name mod)
- (NonLocalDef ImplicitImport (omit_fn name))
- new_cache = addToFM cache key new_name
+
+ -- A hit in the cache! We are at the binding site of the name, which is
+ -- the time we know all about the Name's host Module (in particular, which
+ -- package it comes from), so update the Module in the name.
+ -- But otherwise *leave the Provenance alone*:
+ --
+ -- * For imported names, the Provenance may already be correct.
+ -- e.g. We imported Prelude.hi, and set the provenance of PrelShow.Show
+ -- to 'UserImport from Prelude'. Note that we havn't yet opened PrelShow.hi
+ -- Later we find we really need PrelShow.Show, so we open PrelShow.hi, and
+ -- that's when we find the binding occurrence of Show.
+ --
+ -- * For locally defined names, we do a setProvenance on the Name
+ -- right after newTopBinder, and then use updateProveances to finally
+ -- set the provenances in the cache correctly.
+ --
+ -- NB: for wired-in names it's important not to
+ -- forget that they are wired in even when compiling that module
+ -- (else we spit out redundant defns into the interface file)
+
+ Just name -> let
+ new_name = setNameModule name mod
+ new_cache = addToFM cache key new_name
in
- setNameSupplyRn (us, inst_ns, new_cache) `thenRn_`
+ setNameSupplyRn (us, inst_ns, new_cache, ipcache) `thenRn_`
+ traceRn (text "newTopBinder: overwrite" <+> ppr new_name) `thenRn_`
returnRn new_name
-
- Nothing -> -- Miss in the cache!
- -- Build a new original name, and put it in the cache
- getOmitQualFn `thenRn` \ omit_fn ->
- let
+
+ -- Miss in the cache!
+ -- Build a completely new Name, and put it in the cache
+ -- Even for locally-defined names we use implicitImportProvenance;
+ -- updateProvenances will set it to rights
+ Nothing -> let
(us', us1) = splitUniqSupply us
uniq = uniqFromSupply us1
- name = mkGlobalName uniq mod occ (NonLocalDef ImplicitImport (omit_fn name))
- -- For in-scope things we improve the provenance
- -- in RnNames.importsFromImportDecl
- new_cache = addToFM cache key name
+ new_name = mkGlobalName uniq mod occ implicitImportProvenance
+ new_cache = addToFM cache key new_name
in
- setNameSupplyRn (us', inst_ns, new_cache) `thenRn_`
- returnRn name
+ setNameSupplyRn (us', inst_ns, new_cache, ipcache) `thenRn_`
+ traceRn (text "newTopBinder: new" <+> ppr new_name) `thenRn_`
+ returnRn new_name
--- Make an imported global name, checking first to see if it's in the cache
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) ->
+ = 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) `thenRn_`
+ Just name -> traceRn (text "mkImportedGlobalName: hit" <+> ppr name) `thenRn_`
+ returnRn name
+ Nothing -> setNameSupplyRn (us', inst_ns, new_cache, ipcache) `thenRn_`
+ traceRn (text "mkImportedGlobalName: new" <+> ppr name) `thenRn_`
returnRn name
where
(us', us1) = splitUniqSupply us
uniq = uniqFromSupply us1
- name = mkGlobalName uniq (mkVanillaModule mod_name) occ
- (NonLocalDef ImplicitImport False)
+ 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)
mkImportedGlobalName mod_name (rdrNameOcc rdr_name)
-newLocalTopBinder :: Module -> OccName
- -> (Name -> ExportFlag) -> SrcLoc
- -> RnM d Name
-newLocalTopBinder mod occ rec_exp_fn loc
- = -- First check the cache
- getNameSupplyRn `thenRn` \ (us, inst_ns, cache) ->
- let
- key = (moduleName mod,occ)
- mk_prov 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 newLocallyDefinedGlobalName is used only
- -- at binding occurrences, we may as well get the provenance
- -- dead right first time; hence the rec_exp_fn passed in
- in
- case lookupFM cache key of
-
- -- A hit in the cache!
- -- Overwrite whatever provenance is in the cache already;
- -- this updates WiredIn things and known-key things,
- -- which are there from the start, to LocalDef.
- --
- -- It also means that if there are two defns for the same thing
- -- in a module, then each gets a separate SrcLoc
- Just name -> let
- new_name = setNameProvenance name (mk_prov new_name)
- new_cache = addToFM cache key new_name
- in
- setNameSupplyRn (us, inst_ns, new_cache) `thenRn_`
- returnRn new_name
-
- -- Miss in the cache!
- -- Build a new original name, and put it in the cache
- Nothing -> let
- (us', us1) = splitUniqSupply us
- uniq = uniqFromSupply us1
- new_name = mkGlobalName uniq mod occ (mk_prov new_name)
- new_cache = addToFM cache key new_name
- in
- setNameSupplyRn (us', inst_ns, new_cache) `thenRn_`
- returnRn new_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)
\end{code}
%*********************************************************
%* *
-\subsection{Dfuns and default methods
+\subsection{Dfuns and default methods}
%* *
%*********************************************************
-@newImplicitBinder@ is used for (a) dfuns (b) default methods, defined in this module
+@newImplicitBinder@ is used for
+ (a) dfuns (RnSource.rnDecl on InstDecls)
+ (b) default methods (RnSource.rnDecl on ClassDecls)
+when these dfuns/default methods are defined in the module being compiled
\begin{code}
newImplicitBinder occ src_loc
= getModuleRn `thenRn` \ mod_name ->
- newLocalTopBinder (mkThisModule mod_name) occ (\_ -> Exported) src_loc
+ newTopBinder (mkThisModule mod_name) occ `thenRn` \ name ->
+ returnRn (setNameProvenance name (LocalDef src_loc Exported))
\end{code}
Make a name for the dict fun for an instance decl
\begin{code}
newDFunName :: (OccName, OccName) -> SrcLoc -> RnMS Name
newDFunName key@(cl_occ, tycon_occ) loc
- = newInstUniq key `thenRn` \ inst_uniq ->
- newImplicitBinder (mkDFunOcc cl_occ tycon_occ inst_uniq) 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}
\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
+getDFunKey (HsForAllTy _ _ ty) = getDFunKey ty
+getDFunKey (HsFunTy _ ty) = getDFunKey ty
+getDFunKey (HsPredTy (HsPClass cls (ty:_))) = (nameOccName cls, get_tycon_key ty)
+
+get_tycon_key (HsTyVar tv) = getOccName tv
+get_tycon_key (HsAppTy ty _) = get_tycon_key ty
+get_tycon_key (HsTupleTy (HsTupCon n _) tys) = getOccName n
+get_tycon_key (HsListTy _) = getOccName listTyCon
+get_tycon_key (HsFunTy _ _) = getOccName funTyCon
\end{code}
\begin{code}
-------------------------------------
-bindLocatedLocalsRn :: SDoc -- Documentation string for error message
+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_`
+ getModeRn `thenRn` \ mode ->
getLocalNameEnv `thenRn` \ name_env ->
- (if opt_WarnNameShadowing
- then
- mapRn_ (check_shadow name_env) rdr_names_w_loc
- else
- returnRn ()
+
+ -- Warn about shadowing, but only in source modules
+ (case mode of
+ SourceMode | opt_WarnNameShadowing -> mapRn_ (check_shadow name_env) rdr_names_w_loc
+ other -> returnRn ()
) `thenRn_`
- getNameSupplyRn `thenRn` \ (us, inst_ns, cache) ->
- getModeRn `thenRn` \ mode ->
+ getNameSupplyRn `thenRn` \ (us, inst_ns, cache, ipcache) ->
let
n = length rdr_names_w_loc
(us', us1) = splitUniqSupply us
-- Keep track of whether the name originally came from
-- an interface file.
in
- setNameSupplyRn (us', inst_ns, cache) `thenRn_`
+ setNameSupplyRn (us', inst_ns, cache, ipcache) `thenRn_`
let
new_name_env = addListToRdrEnv name_env (map fst rdr_names_w_loc `zip` names)
bindCoreLocalFVRn rdr_name enclosed_scope
= getSrcLocRn `thenRn` \ loc ->
getLocalNameEnv `thenRn` \ name_env ->
- getNameSupplyRn `thenRn` \ (us, inst_ns, cache) ->
+ 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) `thenRn_`
+ 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) ->
+ setLocalNameEnv new_name_env (enclosed_scope name) `thenRn` \ (result, fvs) ->
returnRn (result, delFromNameSet fvs name)
bindCoreLocalsFVRn [] thing_inside = thing_inside []
bindCoreLocalsFVRn bs $ \ names' ->
thing_inside (name':names')
+bindLocalNames names enclosed_scope
+ = getLocalNameEnv `thenRn` \ name_env ->
+ setLocalNameEnv (addListToRdrEnv name_env pairs)
+ enclosed_scope
+ where
+ pairs = [(mkRdrUnqual (nameOccName n), n) | n <- names]
+
-------------------------------------
bindLocalRn doc rdr_name enclosed_scope
= getSrcLocRn `thenRn` \ loc ->
returnRn (thing, delListFromNameSet fvs names)
-------------------------------------
-extendTyVarEnvFVRn :: [HsTyVar Name] -> RnMS (a, FreeVars) -> RnMS (a, FreeVars)
+bindUVarRn :: SDoc -> RdrName -> (Name -> RnMS (a, FreeVars)) -> RnMS (a, FreeVars)
+bindUVarRn = bindLocalRn
+
+-------------------------------------
+extendTyVarEnvFVRn :: [HsTyVarBndr 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) ->
+ = bindLocalNames tyvar_names enclosed_scope `thenRn` \ (thing, fvs) ->
returnRn (thing, delListFromNameSet fvs tyvar_names)
+ where
+ tyvar_names = hsTyVarNames tyvars
-bindTyVarsRn :: SDoc -> [HsTyVar RdrName]
- -> ([HsTyVar Name] -> RnMS a)
+bindTyVarsRn :: SDoc -> [HsTyVarBndr RdrName]
+ -> ([HsTyVarBndr 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)
+bindTyVars2Rn :: SDoc -> [HsTyVarBndr RdrName]
+ -> ([Name] -> [HsTyVarBndr Name] -> RnMS a)
-> RnMS a
bindTyVars2Rn doc_str tyvar_names enclosed_scope
= getSrcLocRn `thenRn` \ loc ->
let
- located_tyvars = [(getTyVarName tv, loc) | tv <- tyvar_names]
+ located_tyvars = [(hsTyVarName 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))
+bindTyVarsFVRn :: SDoc -> [HsTyVarBndr RdrName]
+ -> ([HsTyVarBndr 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))
+bindTyVarsFV2Rn :: SDoc -> [HsTyVarBndr RdrName]
+ -> ([Name] -> [HsTyVarBndr Name] -> RnMS (a, FreeVars))
-> RnMS (a, FreeVars)
bindTyVarsFV2Rn doc_str rdr_names enclosed_scope
= bindTyVars2Rn doc_str rdr_names $ \ names tyvars ->
\begin{code}
lookupBndrRn rdr_name
- = getNameEnvs `thenRn` \ (global_env, local_env) ->
+ = traceRn (text "lookupBndrRn" <+> ppr rdr_name) `thenRn_`
+ getNameEnvs `thenRn` \ (global_env, local_env) ->
-- Try local env
case lookupRdrEnv local_env rdr_name of {
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)
+ mkImportedGlobalFromRdrName rdr_name `thenRn` \ n ->
+ traceRn (text "lookupBndrRn result:" <+> ppr n) `thenRn_`
+ returnRn n
+
+ 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 looks up an occurrence of a RdrName
lookupOccRn :: RdrName -> RnMS Name
lookupOccRn rdr_name
- = getNameEnvs `thenRn` \ (global_env, local_env) ->
+ = 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
-- class op names in class and instance decls
lookupGlobalOccRn :: RdrName -> RnMS Name
lookupGlobalOccRn rdr_name
- = getNameEnvs `thenRn` \ (global_env, local_env) ->
+ = getNameEnvs `thenRn` \ (global_env, local_env) ->
lookup_global_occ global_env rdr_name
+-- 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 -> RnMS Name
+lookupSigOccRn = lookupBndrRn
+
+
-- Look in both local and global env
lookup_occ global_env local_env rdr_name
= case lookupRdrEnv local_env rdr_name of
-- Not found when processing an imported declaration,
-- so we create a new name for the purpose
InterfaceMode -> mkImportedGlobalFromRdrName rdr_name
+\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).
+
+ \fbox{{\em Jan 98: this comment is wrong: @rnHsType@ uses it quite a bit.}}
-
--- 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).
--- [Jan 98: this comment is wrong: rnHsType uses it quite a bit.]
---
--- 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 Name
+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.
+
+\begin{code}
+lookupImplicitOccRn :: RdrName -> RnM d Name
lookupImplicitOccRn rdr_name = mkImportedGlobalFromRdrName rdr_name
+
+lookupImplicitOccsRn :: [RdrName] -> RnM d NameSet
+lookupImplicitOccsRn rdr_names
+ = mapRn lookupImplicitOccRn rdr_names `thenRn` \ names ->
+ returnRn (mkNameSet names)
\end{code}
-unQualInScope returns a function that takes a Name and tells whether
+@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
+the @Name@'s provenance to guide whether or not to print the name qualified
in error messages.
\begin{code}
%* *
%************************************************************************
-=============== NameEnv ================
+\subsubsection{NameEnv}% ================
+
\begin{code}
plusGlobalRdrEnv :: GlobalRdrEnv -> GlobalRdrEnv -> GlobalRdrEnv
plusGlobalRdrEnv env1 env2 = plusFM_C combine_globals env1 env2
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
+ choose m | n==m && n `hasBetterProv` m = n
+ | otherwise = m
+
is_duplicate :: Name -> Name -> Bool
is_duplicate n1 n2 | isLocallyDefined n1 && isLocallyDefined n2 = False
| otherwise = n1 == n2
- -- 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, *not* eliminate a duplicate.
-
- -- On the other hand, if you import the same name from two different
- -- import statements, we *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
\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.
-=============== ExportAvails ================
-\begin{code}
-mkEmptyExportAvails :: ModuleName -> ExportAvails
-mkEmptyExportAvails mod_name = (unitFM mod_name [], emptyUFM)
-
-mkExportAvails :: ModuleName -> Bool -> GlobalRdrEnv -> [AvailInfo] -> ExportAvails
-mkExportAvails mod_name unqual_imp name_env avails
- = (mod_avail_env, entity_avail_env)
- where
- mod_avail_env = unitFM mod_name unqual_avails
-
- -- unqual_avails is the Avails that are visible in *unqualfied* form
- -- (1.4 Report, Section 5.1.1)
- -- For example, in
- -- import T hiding( f )
- -- we delete f from avails
-
- unqual_avails | not unqual_imp = [] -- Short cut when no unqualified imports
- | otherwise = mapMaybe prune avails
-
- prune (Avail n) | unqual_in_scope n = Just (Avail n)
- prune (Avail n) | otherwise = Nothing
- prune (AvailTC n ns) | null uqs = Nothing
- | otherwise = Just (AvailTC n uqs)
- where
- uqs = filter unqual_in_scope ns
-
- unqual_in_scope n = unQualInScope name_env n
- entity_avail_env = listToUFM [ (name,avail) | avail <- avails,
- name <- availNames avail]
-
-plusExportAvails :: ExportAvails -> ExportAvails -> ExportAvails
-plusExportAvails (m1, e1) (m2, e2)
- = (plusFM_C (++) m1 m2, plusUFM_C plusAvail e1 e2)
- -- ToDo: wasteful: we do this once for each constructor!
-\end{code}
+\subsubsection{AvailInfo}% ================
-=============== AvailInfo ================
\begin{code}
plusAvail (Avail n1) (Avail n2) = Avail n1
-plusAvail (AvailTC n1 ns1) (AvailTC n2 ns2) = AvailTC n1 (nub (ns1 ++ ns2))
+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
+addAvail :: AvailEnv -> AvailInfo -> AvailEnv
+addAvail avails avail = extendNameEnv_C plusAvail avails (availName avail) avail
+
+emptyAvailEnv = emptyNameEnv
+unitAvailEnv :: AvailInfo -> AvailEnv
+unitAvailEnv a = unitNameEnv (availName a) a
+
+plusAvailEnv :: AvailEnv -> AvailEnv -> AvailEnv
+plusAvailEnv = plusNameEnv_C plusAvail
+
+availEnvElts = nameEnvElts
+
addAvailToNameSet :: NameSet -> AvailInfo -> NameSet
addAvailToNameSet names avail = addListToNameSet names (availNames avail)
availsToNameSet :: [AvailInfo] -> NameSet
availsToNameSet avails = foldl addAvailToNameSet emptyNameSet avails
-availName :: AvailInfo -> Name
+availName :: GenAvailInfo name -> name
availName (Avail n) = n
availName (AvailTC n _) = n
-availNames :: AvailInfo -> [Name]
+availNames :: GenAvailInfo name -> [name]
availNames (Avail n) = [n]
availNames (AvailTC n ns) = ns
+addSysAvails :: AvailInfo -> [Name] -> AvailInfo
+addSysAvails avail [] = avail
+addSysAvails (AvailTC n ns) sys = AvailTC n (sys ++ ns)
+
+rdrAvailInfo :: AvailInfo -> RdrAvailInfo
+-- Used when building the avails we are going to put in an interface file
+-- We sort the components to reduce needless wobbling of interfaces
+rdrAvailInfo (Avail n) = Avail (nameOccName n)
+rdrAvailInfo (AvailTC n ns) = AvailTC (nameOccName n) (sortLt (<) (map nameOccName ns))
+
filterAvail :: RdrNameIE -- Wanted
-> AvailInfo -- Available
-> Maybe AvailInfo -- Resulting available;
-- import A( op )
-- where op is a class operation
-filterAvail (IEThingAll _) avail@(AvailTC _ _) = Just avail
+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')))
--- In interfaces, pprAvail gets given the OccName of the "host" thing
-pprAvail avail = getPprStyle $ \ sty ->
- if ifaceStyle sty then
- ppr_avail (pprOccName . nameOccName) avail
- else
- ppr_avail ppr avail
-
-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
+pprAvail (Avail n) = ppr n
\end{code}
%************************************************************************
-\begin{code}
-warnUnusedLocalBinds, warnUnusedTopNames, warnUnusedMatches :: [Name] -> RnM d ()
-warnUnusedTopNames names
- | not opt_WarnUnusedBinds && not opt_WarnUnusedImports = returnRn () -- Don't force ns unless necessary
- | otherwise = warnUnusedBinds (\ is_local -> not is_local) names
+\begin{code}
+warnUnusedModules :: [ModuleName] -> RnM d ()
+warnUnusedModules mods
+ | not opt_WarnUnusedImports = returnRn ()
+ | otherwise = mapRn_ (addWarnRn . unused_mod) mods
+ where
+ unused_mod m = vcat [ptext SLIT("Module") <+> quotes (pprModuleName m) <+>
+ text "is imported, but nothing from it is used",
+ parens (ptext SLIT("except perhaps to re-export instances visible in") <+>
+ quotes (pprModuleName m))]
+
+warnUnusedLocalBinds, warnUnusedImports, warnUnusedMatches :: [Name] -> RnM d ()
+warnUnusedImports names
+ | not opt_WarnUnusedImports
+ = returnRn () -- Don't force names unless necessary
+ | otherwise
+ = warnUnusedBinds (const True) names
warnUnusedLocalBinds ns
| not opt_WarnUnusedBinds = returnRn ()
- | otherwise = warnUnusedBinds (\ is_local -> is_local) ns
+ | otherwise = warnUnusedBinds (const True) ns
warnUnusedMatches names
| opt_WarnUnusedMatches = warnUnusedGroup (const True) names
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)
+ (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
-------------------------
-warnUnusedGroup :: (Bool -> Bool) -> [Name] -> RnM d ()
-warnUnusedGroup _ []
- = returnRn ()
+-- 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 names)))]
+ sep [msg <> colon, nest 4 (fsep (punctuate comma (map ppr filtered_names)))]
where
- name1 = head names
+ 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")
+ 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 "_".
\end{code}
\begin{code}
$$
(ptext SLIT("in") <+> descriptor))
\end{code}
-