%
-% (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}
-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 ( RdrName(..), RdrNameIE,
- rdrNameOcc, ieOcc, isQual, qual
+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 ( getTyVarName, replaceTyVarName )
-import BasicTypes ( Fixity(..), FixityDirection(..), IfaceFlavour(..), pprModule )
-import RnMonad
-import Name ( Name, OccName(..), Provenance(..), ExportFlag(..), NamedThing(..),
- occNameString, occNameFlavour, getSrcLoc,
- NameSet, emptyNameSet, addListToNameSet, nameSetToList,
- mkLocalName, mkGlobalName, modAndOcc,
- nameOccName, setNameProvenance, isVarOcc, getNameProvenance,
- pprProvenance, pprOccName, pprModule, pprNameProvenance,
- isLocalName
- )
-import TyCon ( TyCon )
-import TysWiredIn ( tupleTyCon, listTyCon, charTyCon, intTyCon )
-import FiniteMap
-import Unique ( Unique, Uniquable(..), unboundKey )
-import UniqFM ( listToUFM, plusUFM_C )
-import Maybes ( maybeToBool )
+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 ( 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 )
-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}
-newImportedGlobalName :: Module -> OccName
- -> IfaceFlavour
- -> RnM s d Name
-newImportedGlobalName mod occ hif
- = -- First check the cache
- getNameSupplyRn `thenRn` \ (us, inst_ns, cache) ->
- let
- key = (mod,occ)
- prov = NonLocalDef noSrcLoc hif False
- in
- case lookupFM cache key of
-
- -- A hit in the cache!
- -- If it has no provenance at the moment then set its provenance
- -- so that it has the right HiFlag component.
- -- (This is necessary
- -- for known-key things. For example, GHCmain.lhs imports as SOURCE
- -- Main; but Main.main is a known-key thing.)
- -- Don't fiddle with the provenance if it already has one
- Just name -> case getNameProvenance name of
- NoProvenance -> let
- new_name = setNameProvenance name prov
- new_cache = addToFM cache key new_name
- in
- setNameSupplyRn (us, inst_ns, new_cache) `thenRn_`
- returnRn new_name
- other -> returnRn name
-
- Nothing -> -- Miss in the cache!
- -- Build a new original name, and put it in the cache
- let
- (us', us1) = splitUniqSupply us
- uniq = getUnique us1
- name = mkGlobalName uniq mod occ prov
- new_cache = addToFM cache key name
- in
- setNameSupplyRn (us', inst_ns, new_cache) `thenRn_`
- returnRn name
-
-{-
- let
- pprC ((mod,occ),name) = pprModule mod <> text "." <> pprOccName occ <+> text "--->"
- <+> ppr name
- in
- pprTrace "ng" (vcat [text "newGlobalName miss" <+> pprModule mod <+> pprOccName occ,
- brackets (sep (map pprC (fmToList cache))),
- text ""
- ]) $
--}
-
-
-newLocallyDefinedGlobalName :: Module -> OccName
- -> (Name -> ExportFlag) -> SrcLoc
- -> RnM s d Name
-newLocallyDefinedGlobalName mod occ rec_exp_fn loc
- = -- 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!
- -- Overwrite whatever provenance is in the cache already;
- -- this updates WiredIn things and known-key things,
- -- which are there from the start, to LocalDef.
- Just name -> let
- new_name = setNameProvenance name (LocalDef loc (rec_exp_fn 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
- provenance = LocalDef loc (rec_exp_fn new_name)
- (us', us1) = splitUniqSupply us
- uniq = getUnique us1
- new_name = mkGlobalName uniq mod occ provenance
- new_cache = addToFM cache key new_name
- in
- setNameSupplyRn (us', inst_ns, new_cache) `thenRn_`
- returnRn new_name
-
-
--- 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 ->
- let
- dfun_occ = VarOcc (_PK_ ("$d" ++ show inst_uniq))
- in
- newLocallyDefinedGlobalName mod_name dfun_occ
- (\_ -> Exported) src_loc
-
-newDfunName (Just n) src_loc -- Imported ones have "Just n"
- = getModuleRn `thenRn` \ mod_name ->
- newImportedGlobalName mod_name (rdrNameOcc n) HiFile {- Correct? -}
-
-
-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
-
--- 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
-
-isUnboundName :: Name -> Bool
-isUnboundName name = uniqueOf name == unboundKey
-\end{code}
-
-\begin{code}
-bindLocatedLocalsRn :: SDoc -- 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_`
-
- getLocalNameEnv `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 ->
- let
- new_name_env = addListToFM 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 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
-
-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)
-
- -- Works in any variant of the renamer monad
-checkDupOrQualNames, checkDupNames :: SDoc
- -> [(RdrName, SrcLoc)]
- -> RnM s d ()
-
-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 ()
+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
+ --
+ -- Except for the ":Main.main = ..." definition inserted into
+ -- the Main module
+ --
+ -- 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
+ = newGlobalBinder mod (rdrNameOcc rdr_name) mb_parent (srcSpanStart loc)
where
- (_, dups) = removeDups (\(n1,l1) (n2,l2) -> n1 `compare` n2) rdr_names_w_loc
-
-
--- Yuk!
-ifaceFlavour name = case getNameProvenance name of
- NonLocalDef _ hif _ -> hif
- other -> HiFile -- Shouldn't happen
+ rdr_mod = rdrNameModule rdr_name
\end{code}
-
%*********************************************************
%* *
-\subsection{Looking up names}
+ Source code occurrences
%* *
%*********************************************************
Looking up a name in the RnEnv.
\begin{code}
-lookupRn :: RdrName
- -> Maybe Name -- Result of environment lookup
- -> RnMS s Name
-
-lookupRn rdr_name (Just name)
- = -- Found the name in the envt
- returnRn name -- In interface mode the only things in
- -- the environment are things in local (nested) scopes
-
-lookupRn rdr_name Nothing
- = -- We didn't find the name in the environment
- getModeRn `thenRn` \ mode ->
- case mode of {
- SourceMode -> failWithRn (mkUnboundName rdr_name)
- (unknownNameErr rdr_name) ;
- -- Souurce mode; lookup failure is an error
-
- InterfaceMode _ _ ->
-
-
- ----------------------------------------------------
- -- OK, so we're in interface mode
- -- An Unqual is allowed; interface files contain
- -- unqualified names for locally-defined things, such as
- -- constructors of a data type.
- -- So, qualify the unqualified name with the
- -- module of the interface file, and try again
- case rdr_name of
- Unqual occ -> getModuleRn `thenRn` \ mod ->
- newImportedGlobalName mod occ HiFile
- Qual mod occ hif -> newImportedGlobalName mod occ hif
-
- }
+lookupLocatedBndrRn :: Located RdrName -> RnM (Located Name)
+lookupLocatedBndrRn = wrapLocM lookupBndrRn
+lookupBndrRn :: RdrName -> RnM Name
+-- NOTE: assumes that the SrcSpan of the binder has already been addSrcSpan'd
lookupBndrRn rdr_name
- = lookupNameRn rdr_name `thenRn` \ maybe_name ->
- lookupRn rdr_name maybe_name `thenRn` \ name ->
-
- if isLocalName name then
- returnRn name
- else
-
- ----------------------------------------------------
- -- OK, so we're at the binding site of a top-level defn
- -- Check to see whether its an imported decl
- getModeRn `thenRn` \ mode ->
- case mode of {
- SourceMode -> returnRn name ;
-
- InterfaceMode _ print_unqual_fn ->
-
- ----------------------------------------------------
- -- OK, the binding site of an *imported* defn
- -- so we can make the provenance more informative
- getSrcLocRn `thenRn` \ src_loc ->
- let
- name' = case getNameProvenance name of
- NonLocalDef _ hif _ -> setNameProvenance name
- (NonLocalDef src_loc hif (print_unqual_fn name'))
- other -> name
- in
- returnRn 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
- = lookupNameRn rdr_name `thenRn` \ maybe_name ->
- lookupRn rdr_name maybe_name `thenRn` \ name ->
- let
- name' = mungePrintUnqual rdr_name name
- in
- addOccurrenceName name'
-
--- lookupGlobalOccRn is like lookupOccRn, except that it looks in the global
--- environment only. It's used for record field names only.
-lookupGlobalOccRn :: RdrName -> RnMS s Name
-lookupGlobalOccRn rdr_name
- = lookupGlobalNameRn rdr_name `thenRn` \ maybe_name ->
- lookupRn rdr_name maybe_name `thenRn` \ name ->
- let
- name' = mungePrintUnqual rdr_name name
- in
- addOccurrenceName name'
-
--- mungePrintUnqual is used to make *imported* *occurrences* print unqualified
--- if they were mentioned unqualified in the source code.
--- This improves error messages from the type checker.
--- NB: the binding site is treated differently; see lookupBndrRn
--- After the type checker all occurrences are replaced by the one
--- at the binding site.
-mungePrintUnqual (Qual _ _ _) name = name
-mungePrintUnqual (Unqual _) name = case new_prov of
- Nothing -> name
- Just prov' -> setNameProvenance name prov'
- where
- new_prov = case getNameProvenance name of
- NonLocalDef loc hif False -> Just (NonLocalDef loc hif True)
- other -> Nothing
-
--- 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.
+ = 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.
--
--- 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.]
+-- A separate function (importsFromLocalDecls) reports duplicate top level
+-- decls, so here it's safe just to choose an arbitrary one.
--
--- 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 hif)
- = newImportedGlobalName mod occ hif `thenRn` \ name ->
- addOccurrenceName name
-
-addImplicitOccRn :: Name -> RnMS s Name
-addImplicitOccRn name = addOccurrenceName name
-
-addImplicitOccsRn :: [Name] -> RnMS s ()
-addImplicitOccsRn names = addOccurrenceNames names
+-- 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)
+
+ | 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
-listType_RDR = qual (modAndOcc listType_name)
-tupleType_RDR n = qual (modAndOcc (tupleType_name n))
+lookupLocatedGlobalOccRn :: Located RdrName -> RnM (Located Name)
+lookupLocatedGlobalOccRn = wrapLocM lookupGlobalOccRn
-charType_name = getName charTyCon
-listType_name = getName listTyCon
-tupleType_name n = getName (tupleTyCon n)
-\end{code}
+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
-\begin{code}
-lookupFixity :: RdrName -> RnMS s Fixity
-lookupFixity rdr_name
- = getFixityEnv `thenRn` \ fixity_env ->
- returnRn (lookupFixityEnv fixity_env rdr_name)
+lookupGlobalOccRn rdr_name
+ | not (isSrcRdrName rdr_name)
+ = lookupImportedName rdr_name
+
+ | 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)) }
+
+-------------------------
+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
+ 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
+ doc = ptext SLIT("Need to find") <+> ppr rdr_name
\end{code}
-mkImportFn 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.
+%*********************************************************
+%* *
+ Fixities
+%* *
+%*********************************************************
\begin{code}
-mkImportFn :: RnEnv -> Name -> Bool
-mkImportFn (RnEnv env _)
- = lookup
+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
- lookup name = case lookupFM env (Unqual (nameOccName name)) of
- Just (name', _) -> name == name'
- Nothing -> False
+ rn_sig (FixitySig lv@(L loc v) fix)
+ = addLocM lookupBndrRn lv `thenM` \ new_v ->
+ returnM (new_v, (FixItem (rdrNameOcc v) fix loc))
\end{code}
-%************************************************************************
-%* *
-\subsection{Envt utility functions}
-%* *
-%************************************************************************
-
-=============== RnEnv ================
-\begin{code}
-plusRnEnv (RnEnv n1 f1) (RnEnv n2 f2)
- = plusGlobalNameEnvRn n1 n2 `thenRn` \ n ->
- plusFixityEnvRn f1 f2 `thenRn` \ f ->
- returnRn (RnEnv n f)
-\end{code}
+--------------------------------
+lookupFixity is a bit strange.
+* Nested local fixity decls are put in the local fixity env, which we
+ find with getFixtyEnv
-=============== NameEnv ================
-\begin{code}
-plusGlobalNameEnvRn :: GlobalNameEnv -> GlobalNameEnv -> RnM s d GlobalNameEnv
-plusGlobalNameEnvRn env1 env2
- = mapRn (addErrRn.nameClashErr) (conflictsFM conflicting_name env1 env2) `thenRn_`
- returnRn (env1 `plusFM` env2)
-
-addOneToGlobalNameEnv :: GlobalNameEnv -> RdrName -> (Name, HowInScope) -> RnM s d GlobalNameEnv
-addOneToGlobalNameEnv 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
-
- other -> returnRn (addToFM env rdr_name name)
-
-delOneFromGlobalNameEnv :: GlobalNameEnv -> RdrName -> GlobalNameEnv
-delOneFromGlobalNameEnv env rdr_name = delFromFM env rdr_name
-
-conflicting_name :: (Name, HowInScope) -> (Name, HowInScope) -> Bool
-conflicting_name (n1, FromLocalDefn _) (n2, FromLocalDefn _) = True
-conflicting_name (n1,h1) (n2,h2) = n1 /= 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 HowInScope fields
+* Imported fixities are found in the HIT or PIT
-lookupNameEnv :: NameEnv -> RdrName -> Maybe Name
-lookupNameEnv = lookupFM
-\end{code}
+* 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
-=============== FixityEnv ================
\begin{code}
-plusFixityEnvRn f1 f2
- = mapRn (addErrRn.fixityClashErr) (conflictsFM bad_fix f1 f2) `thenRn_`
- returnRn (f1 `plusFM` f2)
-
-addOneToFixityEnv env rdr_name fixity = addToFM env rdr_name fixity
+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
+ doc = ptext SLIT("Checking fixity for") <+> ppr name
+ name_mod = nameModuleName name
-lookupFixityEnv env rdr_name
- = case lookupFM env rdr_name of
- Just (fixity,_) -> fixity
- Nothing -> Fixity 9 InfixL -- Default case
+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}
-bad_fix :: (Fixity, HowInScope) -> (Fixity, HowInScope) -> Bool
-bad_fix (f1,_) (f2,_) = f1 /= f2
+%************************************************************************
+%* *
+ Rebindable names
+ Dealing with rebindable syntax is driven by the
+ Opt_NoImplicitPrelude dynamic flag.
-pprFixityProvenance :: (Fixity, HowInScope) -> SDoc
-pprFixityProvenance (fixity, how_in_scope) = ppr how_in_scope
-\end{code}
+ In "deriving" code we don't want to use rebindable syntax
+ so we switch off the flag locally
+%* *
+%************************************************************************
+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.
-=============== ExportAvails ================
\begin{code}
-mkExportAvails :: Module -> Bool -> GlobalNameEnv -> [AvailInfo] -> ExportAvails
-mkExportAvails mod_name unqual_imp name_env avails
- = (mod_avail_env, entity_avail_env)
+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
- 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 = [prune avail | avail <- avails]
-
- prune (Avail n) | unqual_in_scope n = Avail n
- prune (Avail n) | otherwise = NotAvailable
- prune (AvailTC n ns) = AvailTC n (filter unqual_in_scope ns)
+ normal_case = returnM (std_name, emptyFVs)
- unqual_in_scope n = Unqual (nameOccName n) `elemFM` name_env
-
- entity_avail_env = listToUFM [ (name,avail) | avail <- avails,
- name <- availEntityNames avail]
+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 ->
-plusExportAvails :: ExportAvails -> ExportAvails -> ExportAvails
-plusExportAvails (m1, e1) (m2, e2)
- = (plusFM_C (++) m1 m2, plusUFM_C plusAvail e1 e2)
+ 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}
-=============== AvailInfo ================
+%*********************************************************
+%* *
+\subsection{Binding}
+%* *
+%*********************************************************
+
\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 = pprPanic "RnEnv.plusAvail" (hsep [pprAvail a1,pprAvail a2])
-#endif
-
-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 ie, pprAvail avail]) $
- NotAvailable
+newLocalsRn :: [Located RdrName] -> RnM [Name]
+newLocalsRn rdr_names_w_loc
+ = newUniqueSupply `thenM` \ us ->
+ returnM (zipWith mk rdr_names_w_loc (uniqsFromSupply us))
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 )
- AvailTC n [n]
-
-filterAvail (IEThingAbs _) avail@(Avail n) = avail -- Type synonyms
-
-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
-
-filterAvail (IEThingAll _) avail@(AvailTC _ _) = avail
-
-filterAvail ie avail = NotAvailable
-
-
--- 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 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
-\end{code}
-
+ 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_`
+
+ -- Warn about shadowing, but only in source modules
+ ifOptM Opt_WarnNameShadowing
+ (checkShadowing doc_str rdr_names_w_loc) `thenM_`
+
+ -- 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)
+
+
+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)
+
+
+-------------------------------------
+ -- 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)
+
+-------------------------------------
+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 -> [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
+
+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)
+
+-------------------------------------
+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
+ (_, 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}
%************************************************************************
%* *
-\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
- -> Maybe (a,(b,b))
-conflictFM bad fm key elt
- = case lookupFM fm key of
- Just elt' | bad elt elt' -> Just (key,(elt,elt'))
- other -> Nothing
+-- 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}
-warnUnusedBinds, warnUnusedMatches, warnUnusedImports :: NameSet -> RnM s d ()
+warnUnusedModules :: [ModuleName] -> RnM ()
+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))]
-warnUnusedBinds names
- | opt_WarnUnusedBinds = warnUnusedNames names
- | otherwise = returnRn ()
+warnUnusedImports, warnUnusedTopBinds :: [GlobalRdrElt] -> RnM ()
+warnUnusedImports gres = ifOptM Opt_WarnUnusedImports (warnUnusedGREs gres)
+warnUnusedTopBinds gres = ifOptM Opt_WarnUnusedBinds (warnUnusedGREs gres)
-warnUnusedMatches names
- | opt_WarnUnusedMatches = warnUnusedNames names
- | otherwise = returnRn ()
+warnUnusedLocalBinds, warnUnusedMatches :: [Name] -> RnM ()
+warnUnusedLocalBinds names = ifOptM Opt_WarnUnusedBinds (warnUnusedLocals names)
+warnUnusedMatches names = ifOptM Opt_WarnUnusedMatches (warnUnusedLocals names)
-warnUnusedImports names
- | opt_WarnUnusedImports = warnUnusedNames names
- | otherwise = returnRn ()
+-------------------------
+-- Helpers
+warnUnusedGREs gres
+ = warnUnusedBinds [(n,Just p) | GRE {gre_name = n, gre_prov = p} <- gres]
-warnUnusedNames :: NameSet -> RnM s d ()
-warnUnusedNames names
- = mapRn warn (nameSetToList names) `thenRn_`
- returnRn ()
- where
- warn name = pushSrcLocRn (getSrcLoc name) $
- addWarnRn (unusedNameWarn name)
+warnUnusedLocals names
+ = warnUnusedBinds [(n,Nothing) | n<-names]
-unusedNameWarn name = quotes (ppr name) <+> ptext SLIT("is bound but not used")
+warnUnusedBinds :: [(Name,Maybe Provenance)] -> RnM ()
+warnUnusedBinds names = mappM_ warnUnusedName (filter reportable names)
+ where reportable (name,_) = reportIfUnused (nameOccName name)
-nameClashErr (rdr_name, ((_,how_in_scope1), (_, how_in_scope2)))
- = hang (hsep [ptext SLIT("Conflicting definitions for"), quotes (ppr rdr_name)])
- 4 (vcat [ppr how_in_scope1,
- ppr how_in_scope2])
+-------------------------
-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])
+warnUnusedName :: (Name, Maybe Provenance) -> RnM ()
+warnUnusedName (name, prov)
+ = addWarnAt loc (sep [msg <> colon, nest 4 (ppr name)])
+ -- TODO should be a proper span
+ where
+ (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}
-shadowedNameWarn shadow
- = hcat [ptext SLIT("This binding for"),
+\begin{code}
+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 doc shadow
+ = hsep [ptext SLIT("This binding for"),
quotes (ppr shadow),
ptext SLIT("shadows an existing binding")]
+ $$ doc
unknownNameErr name
- = sep [text flavour, ptext SLIT("not in scope:"), quotes (ppr name)]
+ = sep [ptext SLIT("Not in scope:"),
+ if isVarOcc occ_name then quotes (ppr name)
+ else text (occNameFlavour occ_name)
+ <+> quotes (ppr name)]
where
- flavour = occNameFlavour (rdrNameOcc name)
-
-qualNameErr descriptor (name,loc)
- = pushSrcLocRn loc $
- addErrRn (hsep [ ptext SLIT("Invalid use of qualified name"),
- quotes (ppr name),
- ptext SLIT("in"),
- descriptor])
-
-dupNamesErr descriptor ((name,loc) : dup_things)
- = pushSrcLocRn loc $
- addErrRn (hsep [ptext SLIT("Conflicting definitions for"),
- quotes (ppr name),
- ptext SLIT("in"), descriptor])
-\end{code}
+ occ_name = rdrNameOcc name
+unknownInstBndrErr cls op
+ = quotes (ppr op) <+> ptext SLIT("is not a (visible) method of class") <+> quotes (ppr cls)
+
+badOrigBinding name
+ = ptext SLIT("Illegal binding of built-in syntax:") <+> ppr (rdrNameOcc name)
+ -- The rdrNameOcc is because we don't want to print Prelude.(,)
+
+dupNamesErr descriptor (L loc name : dup_things)
+ = addSrcSpan loc $
+ addErr ((ptext SLIT("Conflicting definitions for") <+> quotes (ppr name))
+ $$
+ descriptor)
+\end{code}
projects / ghc-hetmet.git / blobdiff