\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,
+ bindSigTyVarsFV, bindPatSigTyVars, bindPatSigTyVarsFV,
+ bindTyVarsRn, extendTyVarEnvFVRn,
+ bindLocalFixities,
+
+ checkDupNames, mapFvRn,
+ warnUnusedMatches, warnUnusedModules, warnUnusedImports,
+ warnUnusedTopBinds, warnUnusedLocalBinds,
+ dataTcOccs, unknownNameErr,
+ ) where
#include "HsVersions.h"
-import {-# SOURCE #-} RnHiFiles( loadInterface )
-
-import FlattenInfo ( namesNeededForFlattening )
-import HsSyn
-import RnHsSyn ( RenamedFixitySig )
-import RdrHsSyn ( RdrNameHsType, 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(..),
- Deprecations(..), lookupDeprec, isLocalGRE,
- extendLocalRdrEnv, availName, availNames,
- lookupFixity
+import LoadIface ( loadHomeInterface, loadSrcInterface )
+import IfaceEnv ( lookupOrig, newGlobalBinder, newIPName )
+import HsSyn ( FixitySig(..), ReboundNames, HsExpr(..),
+ HsType(..), HsExplicitForAll(..), LHsTyVarBndr, LHsType,
+ LSig, Sig(..), Fixity, hsLTyVarName, hsLTyVarLocNames, replaceTyVarName )
+import RdrHsSyn ( extractHsTyRdrTyVars )
+import RdrName ( RdrName, rdrNameModule, isQual, isUnqual, isOrig,
+ mkRdrUnqual, setRdrNameSpace, rdrNameOcc,
+ pprGlobalRdrEnv, lookupGRE_RdrName,
+ isExact_maybe, isSrcRdrName,
+ GlobalRdrElt(..), GlobalRdrEnv, lookupGlobalRdrEnv,
+ isLocalGRE, extendLocalRdrEnv, elemLocalRdrEnv, lookupLocalRdrEnv,
+ Provenance(..), pprNameProvenance, ImportSpec(..)
)
+import HscTypes ( availNames, ModIface(..), FixItem(..), lookupFixity )
import TcRnMonad
-import Name ( Name, getName, getSrcLoc, nameIsLocalOrFrom, isWiredInName,
- mkInternalName, mkExternalName, mkIPName,
- nameOccName, setNameModuleAndLoc, nameModule )
+import Name ( Name, nameIsLocalOrFrom, mkInternalName,
+ nameSrcLoc, nameOccName, nameModule, nameParent, isExternalName )
import NameSet
-import OccName ( OccName, tcName, isDataOcc, occNameUserString, occNameFlavour )
-import Module ( Module, ModuleName, moduleName, mkVanillaModule )
-import PrelNames ( mkUnboundName, intTyConName, qTyConName,
- boolTyConName, funTyConName,
- unpackCStringName, unpackCStringFoldrName, unpackCStringUtf8Name,
- eqStringName, printName,
- bindIOName, returnIOName, failIOName, thenIOName,
- templateHaskellNames
- )
-import TysWiredIn ( unitTyCon ) -- A little odd
-import FiniteMap
+import OccName ( tcName, isDataOcc, occNameFlavour, reportIfUnused )
+import Module ( Module )
+import PrelNames ( mkUnboundName, rOOT_MAIN, iNTERACTIVE, consDataConKey, hasKey )
import UniqSupply
-import SrcLoc ( SrcLoc, noSrcLoc )
+import BasicTypes ( IPName, mapIPName )
+import SrcLoc ( SrcSpan, srcSpanStart, Located(..), eqLocated, unLoc,
+ srcLocSpan, getLoc, combineSrcSpans, srcSpanStartLine, srcSpanEndLine )
import Outputable
-import ListSetOps ( removeDups, equivClasses )
-import BasicTypes ( mapIPName, FixitySig(..) )
-import List ( nub )
-import CmdLineOpts
-import FastString ( FastString )
+import Util ( sortLe )
+import ListSetOps ( removeDups )
+import List ( nubBy )
+import DynFlags
\end{code}
%*********************************************************
%* *
-\subsection{Making new names}
+ Source-code binders
%* *
%*********************************************************
\begin{code}
-newTopBinder :: Module -> RdrName -> SrcLoc -> TcRn m Name
- -- newTopBinder puts into the cache the binder with the
- -- module information set correctly. When the decl is later renamed,
- -- the binding site will thereby get the correct module.
- -- There maybe occurrences that don't have the correct Module, but
- -- by the typechecker will propagate the binding definition to all
- -- the occurrences, so that doesn't matter
-
-newTopBinder mod rdr_name loc
+newTopSrcBinder :: Module -> Maybe Name -> Located RdrName -> RnM Name
+newTopSrcBinder this_mod mb_parent (L loc rdr_name)
| Just name <- isExact_maybe rdr_name
- = returnM 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
+ ASSERT2( isExternalName name, ppr name )
+ do checkErr (this_mod == nameModule name)
+ (badOrigBinding rdr_name)
+ returnM name
- | otherwise
- = -- First check the cache
- getNameCache `thenM` \ name_supply ->
- let
- occ = rdrNameOcc rdr_name
- key = (moduleName mod, occ)
- cache = nsNames name_supply
- in
- case lookupFM cache key of
-
- -- A hit in the cache! We are at the binding site of the name, and
- -- this is the moment when we know all about
- -- a) the Name's host Module (in particular, which
- -- package it comes from)
- -- b) its defining SrcLoc
- -- So we update this info
-
- Just name
- | isWiredInName name -> returnM name
- -- Don't mess with wired-in names. Apart from anything
- -- else, their wired-in-ness is in the SrcLoca
- | otherwise
- -> let
- new_name = setNameModuleAndLoc name mod loc
- new_cache = addToFM cache key new_name
- in
- setNameCache (name_supply {nsNames = new_cache}) `thenM_`
- returnM new_name
-
- -- 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 -> addNewName name_supply key mod occ loc
-
-newGlobalName :: ModuleName -> OccName -> TcRn m 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 (newTopBinder)
- -- The place-holder Name doesn't have the right SrcLoc, and its
- -- Module won't have the right Package either.
- --
- -- (We have to pass a ModuleName, not a Module, because we may be
- -- simply looking at an occurrence M.x in an interface file.)
- --
- -- 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).
-newGlobalName mod_name occ
- = getNameCache `thenM` \ name_supply ->
- let
- key = (mod_name, occ)
- cache = nsNames name_supply
- in
- case lookupFM cache key of
- Just name -> -- traceRn (text "newGlobalName: hit" <+> ppr name) `thenM_`
- returnM name
-
- Nothing -> -- traceRn (text "newGlobalName: new" <+> ppr name) `thenM_`
- addNewName name_supply key (mkVanillaModule mod_name) occ noSrcLoc
-
--- Look up a "system name" in the name cache.
--- This is done by the type checker...
--- For *source* declarations, this will put the thing into the name cache
--- For *interface* declarations, RnHiFiles.getSysBinders will already have
--- put it into the cache.
-lookupSysName :: Name -- Base name
- -> (OccName -> OccName) -- Occurrence name modifier
- -> TcRn m Name -- System name
-lookupSysName base_name mk_sys_occ
- = getNameCache `thenM` \ name_supply ->
- let
- mod = nameModule base_name
- occ = mk_sys_occ (nameOccName base_name)
- key = (moduleName mod, occ)
- in
- case lookupFM (nsNames name_supply) key of
- Just name -> returnM name
- Nothing -> addNewName name_supply key mod occ noSrcLoc
-newIPName rdr_name_ip
- = getNameCache `thenM` \ name_supply ->
- let
- ipcache = nsIPs name_supply
- in
- 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
-
-addNewName :: NameCache -> (ModuleName,OccName)
- -> Module -> OccName -> SrcLoc -> TcRn m Name
--- Internal function: extend the name cache, dump it back into
--- the monad, and return the new name
--- (internal, hence the rather redundant interface)
-addNewName name_supply key mod occ loc
- = setNameCache new_name_supply `thenM_`
- returnM name
+ | isOrig rdr_name
+ = do checkErr (rdr_mod == this_mod || rdr_mod == rOOT_MAIN)
+ (badOrigBinding rdr_name)
+ -- When reading External Core we get Orig names as binders,
+ -- but they should agree with the module gotten from the monad
+ --
+ -- We can get built-in syntax showing up here too, sadly. If you type
+ -- data T = (,,,)
+ -- the constructor is parsed as a type, and then RdrHsSyn.tyConToDataCon
+ -- uses setRdrNameSpace to make it into a data constructors. At that point
+ -- the nice Exact name for the TyCon gets swizzled to an Orig name.
+ -- Hence the badOrigBinding error message.
+ --
+ -- Except for the ":Main.main = ..." definition inserted into
+ -- the Main module; ugh!
+
+ -- Because of this latter case, we call newGlobalBinder with a 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 rdr_mod (rdrNameOcc rdr_name) mb_parent
+ (srcSpanStart loc) --TODO, should pass the whole span
+
+ | otherwise
+ = newGlobalBinder this_mod (rdrNameOcc rdr_name) mb_parent (srcSpanStart loc)
where
- (us', us1) = splitUniqSupply (nsUniqs name_supply)
- uniq = uniqFromSupply us1
- name = mkExternalName uniq mod occ loc
- new_cache = addToFM (nsNames name_supply) key name
- new_name_supply = name_supply {nsUniqs = us', nsNames = new_cache}
+ rdr_mod = rdrNameModule rdr_name
\end{code}
%*********************************************************
%* *
-\subsection{Looking up names}
+ Source code occurrences
%* *
%*********************************************************
Looking up a name in the RnEnv.
\begin{code}
+lookupLocatedBndrRn :: Located RdrName -> RnM (Located Name)
+lookupLocatedBndrRn = wrapLocM lookupBndrRn
+
+lookupBndrRn :: RdrName -> RnM Name
+-- NOTE: assumes that the SrcSpan of the binder has already been setSrcSpan'd
lookupBndrRn rdr_name
= getLocalRdrEnv `thenM` \ local_env ->
- case lookupRdrEnv local_env rdr_name of
+ case lookupLocalRdrEnv 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.
+lookupLocatedTopBndrRn :: Located RdrName -> RnM (Located Name)
+lookupLocatedTopBndrRn = wrapLocM lookupTopBndrRn
- -- There should never be a qualified name in a binding position
- -- The parser could check this, but doesn't (yet)
- | isQual rdr_name
- = getSrcLocM `thenM` \ loc ->
- qualNameErr (text "In its declaration") (rdr_name,loc) `thenM_`
- returnM (mkUnboundName rdr_name)
-
- | otherwise
- = ASSERT( not (isOrig rdr_name) )
- -- Original names are used only for occurrences,
- -- not binding sites
-
- 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:
+lookupTopBndrRn :: RdrName -> RnM Name
+-- Look up a top-level source-code binder. We may be looking up an unqualified 'f',
+-- and there may be several imported 'f's too, which must not confuse us.
+-- For example, this is OK:
-- import Foo( f )
-- infix 9 f -- The 'f' here does not need to be qualified
-- f x = x -- Nor here, of course
+-- So we have to filter out the non-local ones.
+--
+-- A separate function (importsFromLocalDecls) reports duplicate top level
+-- decls, so here it's safe just to choose an arbitrary one.
+--
+-- There should never be a qualified name in a binding position in Haskell,
+-- but there can be if we have read in an external-Core file.
+-- The Haskell parser checks for the illegal qualified name in Haskell
+-- source files, so we don't need to do so here.
-lookupTopSrcBndr_maybe rdr_name
+lookupTopBndrRn 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)
+ = 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 (rdrNameModule rdr_name)
+ (rdrNameOcc rdr_name) Nothing (srcSpanStart loc) }
| 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)
+ = do { mb_gre <- lookupGreLocalRn rdr_name
+ ; case mb_gre of
+ Nothing -> unboundName rdr_name
+ Just gre -> returnM (gre_name gre) }
-
--- lookupSigOccRn is used for type signatures and pragmas
+-- lookupLocatedSigOccRn is used for type signatures and pragmas
-- Is this valid?
-- module A
-- import M( 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
+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
- -- 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
- avail_env = imp_env (tcg_imports gbl_env)
- in
- 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)
-
- | isQual rdr_name -- Should never have a qualified name in a binding position
- = getSrcLocM `thenM` \ loc ->
- qualNameErr (text "In an instance method") (rdr_name,loc) `thenM_`
- returnM (mkUnboundName rdr_name)
-
- | otherwise -- Occurs in derived instances, where we just
- -- refer directly to the right method, and avail_env
- -- isn't available
+ | 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 )
- lookupOrigName rdr_name
+ -- NB: qualified names are rejected by the parser
+ lookupImportedName rdr_name
- 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
+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 lookupRdrEnv local_env rdr_name of
+ case lookupLocalRdrEnv local_env rdr_name of
Just name -> returnM name
Nothing -> lookupGlobalOccRn rdr_name
+lookupLocatedGlobalOccRn :: Located RdrName -> RnM (Located Name)
+lookupLocatedGlobalOccRn = wrapLocM lookupGlobalOccRn
+
+lookupGlobalOccRn :: RdrName -> RnM Name
-- lookupGlobalOccRn is like lookupOccRn, except that it looks in the global
-- environment. It's used only for
-- record field names
-- class op names in class and instance decls
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
+ | 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 -> TcRn m Name
+lookupQualifiedName :: RdrName -> RnM 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
- = newGlobalName (rdrNameModule rdr_name)
- (rdrNameOcc 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 (moduleName mod) (rdrNameOcc rdr_name)
- | 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
- = newGlobalName (rdrNameModule rdr_name) (rdrNameOcc 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)
+ -- Note: we want to behave as we would for a source file import here,
+ -- and respect hiddenness of modules/packages, hence loadSrcInterface.
+ loadSrcInterface doc mod False `thenM` \ iface ->
+
+ 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}
%*********************************************************
%*********************************************************
\begin{code}
+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 :: [RenamedFixitySig] -> RnM a -> RnM a
+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 = extendFixityEnv new_bit thing_inside
+ | otherwise = mappM rn_sig fixes `thenM` \ new_bit ->
+ extendFixityEnv new_bit thing_inside
where
- new_bit = [(n,s) | s@(FixitySig n _ _) <- fixes]
+ rn_sig (FixitySig lv@(L loc v) fix)
+ = addLocM lookupBndrRn lv `thenM` \ new_v ->
+ returnM (new_v, (FixItem (rdrNameOcc v) fix loc))
\end{code}
--------------------------------
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
-- 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)
+ --
+ -- loadHomeInterface will find B.hi even if B is a hidden module,
+ -- and that's what we want.
+ initIfaceTcRn (loadHomeInterface doc name) `thenM` \ iface ->
+ returnM (mi_fix_fn iface (nameOccName name))
where
doc = ptext SLIT("Checking fixity for") <+> ppr name
- name_mod = moduleName (nameModule name)
-\end{code}
+dataTcOccs :: RdrName -> [RdrName]
+-- If the input is a data constructor, return both it and a type
+-- constructor. This is useful when we aren't sure which we are
+-- looking at.
+dataTcOccs rdr_name
+ | Just n <- isExact_maybe rdr_name -- Ghastly special case
+ , n `hasKey` consDataConKey = [rdr_name] -- see note below
+ | isDataOcc occ = [rdr_name_tc, rdr_name]
+ | otherwise = [rdr_name]
+ where
+ occ = rdrNameOcc rdr_name
+ rdr_name_tc = setRdrNameSpace rdr_name tcName
-%*********************************************************
-%* *
-\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
-
- -- 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
-mkTemplateHaskellFVs source_fvs
-#ifdef GHCI
- -- Only if Template Haskell is enabled
- | qTyConName `elemNameSet` source_fvs = templateHaskellNames
-#endif
- | otherwise = emptyFVs
-
--- 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
- `plusFV`
- mkFVs [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!)
+-- If the user typed "[]" or "(,,)", we'll generate an Exact RdrName,
+-- and setRdrNameSpace generates an Orig, which is fine
+-- But it's not fine for (:), because there *is* no corresponding type
+-- constructor. If we generate an Orig tycon for GHC.Base.(:), it'll
+-- appear to be in scope (because Orig's simply allocate a new name-cache
+-- entry) and then we get an error when we use dataTcOccs in
+-- TcRnDriver.tcRnGetInfo. Large sigh.
\end{code}
%************************************************************************
%* *
-\subsection{Re-bindable desugaring names}
+ Rebindable names
+ Dealing with rebindable syntax is driven by the
+ Opt_NoImplicitPrelude dynamic flag.
+
+ In "deriving" code we don't want to use rebindable syntax
+ so we switch off the flag locally
+
%* *
%************************************************************************
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
-
+ = doptM Opt_ImplicitPrelude `thenM` \ implicit_prelude ->
+ if implicit_prelude then normal_case
else
-- Get the similarly named thing from the local environment
lookupOccRn (mkRdrUnqual (nameOccName std_name)) `thenM` \ usr_name ->
- returnM (usr_name, mkFVs [usr_name, std_name])
+ returnM (usr_name, unitFV usr_name)
+ where
+ normal_case = returnM (std_name, emptyFVs)
+
+lookupSyntaxNames :: [Name] -- Standard names
+ -> RnM (ReboundNames Name, FreeVars) -- See comments with HsExpr.ReboundNames
+lookupSyntaxNames std_names
+ = doptM Opt_ImplicitPrelude `thenM` \ implicit_prelude ->
+ if implicit_prelude then normal_case
+ else
+ -- Get the similarly named thing from the local environment
+ mappM (lookupOccRn . mkRdrUnqual . nameOccName) std_names `thenM` \ usr_names ->
+
+ returnM (std_names `zip` map HsVar usr_names, mkFVs usr_names)
+ where
+ normal_case = returnM (std_names `zip` map HsVar std_names, emptyFVs)
\end{code}
%*********************************************************
\begin{code}
-newLocalsRn :: [(RdrName,SrcLoc)]
- -> RnM [Name]
+newLocalsRn :: [Located RdrName] -> 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
-
+ = newUniqueSupply `thenM` \ us ->
+ returnM (zipWith mk rdr_names_w_loc (uniqsFromSupply us))
+ where
+ mk (L loc rdr_name) uniq
+ | Just name <- isExact_maybe rdr_name = name
+ -- This happens in code generated by Template Haskell
+ | otherwise = ASSERT2( isUnqual rdr_name, ppr rdr_name )
+ -- We only bind unqualified names here
+ -- lookupRdrEnv doesn't even attempt to look up a qualified RdrName
+ mkInternalName uniq (rdrNameOcc rdr_name) (srcSpanStart loc)
bindLocatedLocalsRn :: SDoc -- Documentation string for error message
- -> [(RdrName,SrcLoc)]
+ -> [Located RdrName]
-> ([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 ->
-
- -- Check for duplicate names
- checkDupOrQualNames doc_str rdr_names_w_loc `thenM_`
+ = -- Check for duplicate names
+ checkDupNames doc_str rdr_names_w_loc `thenM_`
-- 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
-
- (case mode of
- SourceMode -> ifOptM Opt_WarnNameShadowing $
- mappM_ check_shadow rdr_names_w_loc
- other -> returnM ()
- ) `thenM_`
+ 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 ->
- 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)
+ getLocalRdrEnv `thenM` \ local_env ->
+ setLocalRdrEnv (extendLocalRdrEnv local_env names)
+ (enclosed_scope names)
-bindCoreLocalsRn [] thing_inside = thing_inside []
-bindCoreLocalsRn (b:bs) thing_inside = bindCoreLocalRn b $ \ name' ->
- bindCoreLocalsRn bs $ \ names' ->
- thing_inside (name':names')
+bindLocalNames :: [Name] -> RnM a -> RnM a
bindLocalNames names enclosed_scope
= getLocalRdrEnv `thenM` \ name_env ->
setLocalRdrEnv (extendLocalRdrEnv name_env names)
enclosed_scope
+bindLocalNamesFV :: [Name] -> RnM (a, FreeVars) -> RnM (a, FreeVars)
bindLocalNamesFV names enclosed_scope
- = bindLocalNames names $
- enclosed_scope `thenM` \ (thing, fvs) ->
- returnM (thing, delListFromNameSet fvs names)
+ = do { (result, fvs) <- bindLocalNames names enclosed_scope
+ ; returnM (result, 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
-
-- binLocalsFVRn is the same as bindLocalsRn
-- except that it deals with free vars
-bindLocalsFVRn doc rdr_names enclosed_scope
- = bindLocalsRn doc rdr_names $ \ names ->
+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 -> [HsTyVarBndr RdrName]
- -> ([HsTyVarBndr Name] -> RnM a)
+bindTyVarsRn :: SDoc -> [LHsTyVarBndr RdrName]
+ -> ([LHsTyVarBndr Name] -> RnM a)
-> RnM a
+-- Haskell-98 binding of type variables; e.g. within a data type decl
bindTyVarsRn doc_str tyvar_names enclosed_scope
- = getSrcLocM `thenM` \ loc ->
- let
- located_tyvars = [(hsTyVarName tv, loc) | tv <- tyvar_names]
+ = let
+ located_tyvars = hsLTyVarLocNames tyvar_names
in
bindLocatedLocalsRn doc_str located_tyvars $ \ names ->
- enclosed_scope (zipWith replaceTyVarName tyvar_names names)
+ enclosed_scope (zipWith replace tyvar_names names)
+ where
+ replace (L loc n1) n2 = L loc (replaceTyVarName n1 n2)
-bindPatSigTyVars :: [RdrNameHsType]
- -> RnM (a, FreeVars)
- -> RnM (a, FreeVars)
+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 enclosed_scope
- = getLocalRdrEnv `thenM` \ name_env ->
- getSrcLocM `thenM` \ loc ->
- let
- forall_tyvars = nub [ tv | ty <- tys,
- tv <- extractHsTyRdrTyVars ty,
- not (tv `elemFM` name_env)
- ]
+bindPatSigTyVars tys thing_inside
+ = do { scoped_tyvars <- doptM Opt_ScopedTypeVariables
+ ; if not scoped_tyvars then
+ thing_inside []
+ else
+ do { name_env <- getLocalRdrEnv
+ ; let locd_tvs = [ tv | ty <- tys
+ , tv <- extractHsTyRdrTyVars ty
+ , not (unLoc tv `elemLocalRdrEnv` name_env) ]
+ nubbed_tvs = nubBy eqLocated locd_tvs
-- 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)
+ ; bindLocatedLocalsRn doc_sig nubbed_tvs thing_inside }}
+ where
+ doc_sig = text "In a pattern type-signature"
+
+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)
+
+bindSigTyVarsFV :: [LSig Name]
+ -> RnM (a, FreeVars)
+ -> RnM (a, FreeVars)
+-- Bind the top-level forall'd type variables in the sigs.
+-- E.g f :: a -> a
+-- f = rhs
+-- The 'a' scopes over the rhs
+--
+-- NB: there'll usually be just one (for a function binding)
+-- but if there are many, one may shadow the rest; too bad!
+-- e.g x :: [a] -> [a]
+-- y :: [(a,a)] -> a
+-- (x,y) = e
+-- In e, 'a' will be in scope, and it'll be the one from 'y'!
+bindSigTyVarsFV sigs thing_inside
+ = do { scoped_tyvars <- doptM Opt_ScopedTypeVariables
+ ; if not scoped_tyvars then
+ thing_inside
+ else
+ bindLocalNamesFV tvs thing_inside }
+ where
+ tvs = [ hsLTyVarName ltv
+ | L _ (Sig _ (L _ (HsForAllTy Explicit ltvs _ _))) <- sigs, ltv <- ltvs ]
+ -- Note the pattern-match on "Explicit"; we only bind
+ -- type variables from signatures with an explicit top-level for-all
+
+extendTyVarEnvFVRn :: [Name] -> RnM (a, FreeVars) -> RnM (a, FreeVars)
+ -- This function is used only in rnSourceDecl on InstDecl
+extendTyVarEnvFVRn tyvars thing_inside = bindLocalNamesFV tyvars thing_inside
-------------------------------------
-checkDupOrQualNames, checkDupNames :: SDoc
- -> [(RdrName, SrcLoc)]
- -> TcRn m ()
- -- Works in any variant of the renamer monad
-
-checkDupOrQualNames doc_str rdr_names_w_loc
- = -- Check for use of qualified names
- mappM_ (qualNameErr doc_str) quals `thenM_`
- checkDupNames doc_str rdr_names_w_loc
- where
- quals = filter (isQual . fst) rdr_names_w_loc
-
+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,l1) (n2,l2) -> n1 `compare` n2) rdr_names_w_loc
-\end{code}
-
-
-%************************************************************************
-%* *
-\subsection{GlobalRdrEnv}
-%* *
-%************************************************************************
-
-\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
- -- 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 = parent,
- gre_prov = mk_provenance name,
- gre_deprec = lookupDeprec deprecs name}
-
-\end{code}
-
-\begin{code}
-plusGlobalRdrEnv :: GlobalRdrEnv -> GlobalRdrEnv -> GlobalRdrEnv
-plusGlobalRdrEnv env1 env2 = plusFM_C combine_globals env1 env2
-
-addOneToGlobalRdrEnv :: GlobalRdrEnv -> RdrName -> GlobalRdrElt -> GlobalRdrEnv
-addOneToGlobalRdrEnv env rdr_name name = addToFM_C combine_globals env rdr_name [name]
-
-delOneFromGlobalRdrEnv :: GlobalRdrEnv -> RdrName -> GlobalRdrEnv
-delOneFromGlobalRdrEnv env rdr_name = delFromFM env rdr_name
-
-combine_globals :: [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
-
- g1 `beats` g2 = gre_name g1 == gre_name g2 &&
- gre_prov g1 `hasBetterProv` gre_prov g2
+ (_, dups) = removeDups (\n1 n2 -> unLoc n1 `compare` unLoc n2) rdr_names_w_loc
- is_duplicate :: GlobalRdrElt -> GlobalRdrElt -> Bool
- is_duplicate g1 g2 | isLocalGRE g1 && isLocalGRE g2 = False
- is_duplicate g1 g2 = gre_name g1 == gre_name g2
+-------------------------------------
+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 ))
+ = setSrcSpan loc $ addWarn (shadowedNameWarn doc_str rdr_name)
+ | otherwise = returnM ()
+ in
+ mappM_ check_shadow loc_rdr_names
\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.
-
%************************************************************************
%* *
%************************************************************************
\begin{code}
-warnUnusedModules :: [ModuleName] -> TcRn m ()
+warnUnusedModules :: [(Module,SrcSpan)] -> RnM ()
warnUnusedModules mods
- = ifOptM Opt_WarnUnusedImports (mappM_ (addWarn . unused_mod) mods)
+ = ifOptM Opt_WarnUnusedImports (mappM_ bleat mods)
where
- unused_mod m = vcat [ptext SLIT("Module") <+> quotes (ppr m) <+>
- text "is imported, but nothing from it is used",
+ bleat (mod,loc) = setSrcSpan loc $ addWarn (mk_warn mod)
+ mk_warn 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, warnUnusedTopBinds :: [GlobalRdrElt] -> RnM ()
warnUnusedImports gres = ifOptM Opt_WarnUnusedImports (warnUnusedGREs gres)
warnUnusedTopBinds gres = ifOptM Opt_WarnUnusedBinds (warnUnusedGREs gres)
-warnUnusedLocalBinds, warnUnusedMatches :: [Name] -> TcRn m ()
+warnUnusedLocalBinds, warnUnusedMatches :: [Name] -> RnM ()
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]
+warnUnusedGREs gres
+ = warnUnusedBinds [(n,Just p) | GRE {gre_name = n, gre_prov = p} <- gres]
-warnUnusedBinds :: [(Name,Provenance)] -> TcRn m ()
-warnUnusedBinds names
- = mappM_ warnUnusedGroup groups
- where
- -- Group by provenance
- groups = equivClasses cmp names
- (_,prov1) `cmp` (_,prov2) = prov1 `compare` prov2
-
+warnUnusedLocals names
+ = warnUnusedBinds [(n,Nothing) | n<-names]
+
+warnUnusedBinds :: [(Name,Maybe Provenance)] -> RnM ()
+warnUnusedBinds names = mappM_ warnUnusedName (filter reportable names)
+ where reportable (name,_) = reportIfUnused (nameOccName name)
-------------------------
-warnUnusedGroup :: [(Name,Provenance)] -> TcRn m ()
-warnUnusedGroup names
- | null filtered_names = returnM ()
- | not is_local = returnM ()
- | otherwise
- = addSrcLoc def_loc $
- addWarn $
- sep [msg <> colon, nest 4 (fsep (punctuate comma (map (ppr.fst) filtered_names)))]
+warnUnusedName :: (Name, Maybe Provenance) -> RnM ()
+warnUnusedName (name, prov)
+ = addWarnAt loc $
+ sep [msg <> colon,
+ nest 2 $ occNameFlavour (nameOccName name) <+> quotes (ppr name)]
+ -- TODO should be a proper span
where
- filtered_names = filter reportable names
- (name1, prov1) = head filtered_names
- (is_local, def_loc, msg)
- = case prov1 of
- LocalDef -> (True, getSrcLoc name1, text "Defined but not used")
-
- NonLocalDef (UserImport mod loc _)
- -> (True, loc, text "Imported from" <+> quotes (ppr mod) <+> text "but not used")
-
- reportable (name,_) = case occNameUserString (nameOccName name) of
- ('_' : _) -> False
- zz_other -> True
- -- Haskell 98 encourages compilers to suppress warnings about
- -- unused names in a pattern if they start with "_".
+ (loc,msg) = case prov of
+ Just (Imported is _) ->
+ ( is_loc (head is), imp_from (is_mod imp_spec) )
+ where
+ imp_spec = head is
+ other ->
+ ( srcLocSpan (nameSrcLoc name), unused_msg )
+
+ unused_msg = text "Defined but not used"
+ imp_from mod = text "Imported from" <+> quotes (ppr mod) <+> text "but not used"
\end{code}
\begin{code}
addNameClashErrRn rdr_name (np1:nps)
= addErr (vcat [ptext SLIT("Ambiguous occurrence") <+> quotes (ppr rdr_name),
- ptext SLIT("It could refer to") <+> vcat (msg1 : msgs)])
+ 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
+shadowedNameWarn doc shadow
= hsep [ptext SLIT("This binding for"),
quotes (ppr shadow),
ptext SLIT("shadows an existing binding")]
+ $$ doc
-unknownNameErr name
- = sep [text flavour, ptext SLIT("not in scope:"), quotes (ppr name)]
- where
- flavour = occNameFlavour (rdrNameOcc name)
+unknownNameErr rdr_name
+ = sep [ptext SLIT("Not in scope:"),
+ nest 2 $ occNameFlavour (rdrNameOcc rdr_name) <+> quotes (ppr rdr_name)]
+
+unknownInstBndrErr cls op
+ = quotes (ppr op) <+> ptext SLIT("is not a (visible) method of class") <+> quotes (ppr cls)
badOrigBinding name
= ptext SLIT("Illegal binding of built-in syntax:") <+> ppr (rdrNameOcc name)
-- The rdrNameOcc is because we don't want to print Prelude.(,)
-qualNameErr descriptor (name,loc)
- = addSrcLoc loc $
- addErr (vcat [ ptext SLIT("Invalid use of qualified name") <+> quotes (ppr name),
- descriptor])
-
-dupNamesErr descriptor ((name,loc) : dup_things)
- = addSrcLoc loc $
- addErr ((ptext SLIT("Conflicting definitions for") <+> quotes (ppr name))
- $$
- descriptor)
-
-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) ])
+dupNamesErr :: SDoc -> [Located RdrName] -> RnM ()
+dupNamesErr descriptor located_names
+ = setSrcSpan big_loc $
+ addErr (vcat [ptext SLIT("Conflicting definitions for") <+> quotes (ppr name1),
+ locations,
+ descriptor])
+ where
+ L _ name1 = head located_names
+ locs = map getLoc located_names
+ big_loc = foldr1 combineSrcSpans locs
+ one_line = srcSpanStartLine big_loc == srcSpanEndLine big_loc
+ locations | one_line = empty
+ | otherwise = ptext SLIT("Bound at:") <+>
+ vcat (map ppr (sortLe (<=) locs))
\end{code}
-