%
% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
%
\section[RnSource]{Main pass of renamer}
\begin{code}
module RnSource (
rnSrcDecls, addTcgDUs, rnTyClDecls, findSplice
) where
#include "HsVersions.h"
import RnExpr( rnLExpr )
#ifdef GHCI
import TcSplice ( runQuasiQuoteDecl )
#endif /* GHCI */
import HsSyn
import RdrName
import RdrHsSyn ( extractHsRhoRdrTyVars )
import RnHsSyn
import RnTypes
import RnBinds
import RnEnv
import RnNames
import RnHsDoc ( rnHsDoc, rnMbLHsDoc )
import TcRnMonad
import ForeignCall ( CCallTarget(..) )
import Module
import HscTypes ( Warnings(..), plusWarns )
import Class ( FunDep )
import Name
import NameSet
import NameEnv
import Avail
import Outputable
import Bag
import FastString
import Util ( filterOut )
import SrcLoc
import DynFlags
import HscTypes ( HscEnv, hsc_dflags )
import ListSetOps ( findDupsEq )
import Digraph ( SCC, flattenSCC, stronglyConnCompFromEdgedVertices )
import Control.Monad
import Maybes( orElse )
import Data.Maybe( isNothing )
\end{code}
@rnSourceDecl@ `renames' declarations.
It simultaneously performs dependency analysis and precedence parsing.
It also does the following error checks:
\begin{enumerate}
\item
Checks that tyvars are used properly. This includes checking
for undefined tyvars, and tyvars in contexts that are ambiguous.
(Some of this checking has now been moved to module @TcMonoType@,
since we don't have functional dependency information at this point.)
\item
Checks that all variable occurences are defined.
\item
Checks the @(..)@ etc constraints in the export list.
\end{enumerate}
\begin{code}
rnSrcDecls :: [Name] -> HsGroup RdrName -> RnM (TcGblEnv, HsGroup Name)
rnSrcDecls extra_deps group@(HsGroup { hs_valds = val_decls,
hs_tyclds = tycl_decls,
hs_instds = inst_decls,
hs_derivds = deriv_decls,
hs_fixds = fix_decls,
hs_warnds = warn_decls,
hs_annds = ann_decls,
hs_fords = foreign_decls,
hs_defds = default_decls,
hs_ruleds = rule_decls,
hs_vects = vect_decls,
hs_docs = docs })
= do {
local_fix_env <- makeMiniFixityEnv fix_decls ;
(tc_envs, tc_bndrs) <- getLocalNonValBinders local_fix_env group ;
setEnvs tc_envs $ do {
failIfErrsM ;
inNewEnv (extendRecordFieldEnv tycl_decls inst_decls) $ \ _ -> do {
new_lhs <- rnTopBindsLHS local_fix_env val_decls ;
let { val_binders = collectHsValBinders new_lhs ;
all_bndr_set = addListToNameSet tc_bndrs val_binders ;
val_avails = map Avail val_binders } ;
(tcg_env, tcl_env) <- extendGlobalRdrEnvRn val_avails local_fix_env ;
traceRn (ptext (sLit "Val binders") <+> (ppr val_binders)) ;
setEnvs (tcg_env, tcl_env) $ do {
traceRn (text "Start rnTyClDecls") ;
(rn_tycl_decls, src_fvs1) <- rnTyClDecls extra_deps tycl_decls ;
traceRn (text "Start rnmono") ;
(rn_val_decls, bind_dus) <- rnTopBindsRHS new_lhs ;
traceRn (text "finish rnmono" <+> ppr rn_val_decls) ;
rn_fix_decls <- rnSrcFixityDecls all_bndr_set fix_decls ;
rn_warns <- rnSrcWarnDecls all_bndr_set warn_decls ;
(rn_inst_decls, src_fvs2) <- rnList rnSrcInstDecl inst_decls ;
(rn_rule_decls, src_fvs3) <- setXOptM Opt_ScopedTypeVariables $
rnList rnHsRuleDecl rule_decls ;
(rn_vect_decls, src_fvs4) <- rnList rnHsVectDecl vect_decls ;
(rn_foreign_decls, src_fvs5) <- rnList rnHsForeignDecl foreign_decls ;
(rn_ann_decls, src_fvs6) <- rnList rnAnnDecl ann_decls ;
(rn_default_decls, src_fvs7) <- rnList rnDefaultDecl default_decls ;
(rn_deriv_decls, src_fvs8) <- rnList rnSrcDerivDecl deriv_decls ;
rn_docs <- mapM (wrapLocM rnDocDecl) docs ;
last_tcg_env <- getGblEnv ;
let {rn_group = HsGroup { hs_valds = rn_val_decls,
hs_tyclds = rn_tycl_decls,
hs_instds = rn_inst_decls,
hs_derivds = rn_deriv_decls,
hs_fixds = rn_fix_decls,
hs_warnds = [],
hs_fords = rn_foreign_decls,
hs_annds = rn_ann_decls,
hs_defds = rn_default_decls,
hs_ruleds = rn_rule_decls,
hs_vects = rn_vect_decls,
hs_docs = rn_docs } ;
tycl_bndrs = hsTyClDeclsBinders rn_tycl_decls rn_inst_decls ;
ford_bndrs = hsForeignDeclsBinders rn_foreign_decls ;
other_def = (Just (mkNameSet tycl_bndrs `unionNameSets` mkNameSet ford_bndrs), emptyNameSet) ;
other_fvs = plusFVs [src_fvs1, src_fvs2, src_fvs3, src_fvs4,
src_fvs5, src_fvs6, src_fvs7, src_fvs8] ;
src_dus = [other_def] `plusDU` bind_dus `plusDU` usesOnly other_fvs ;
final_tcg_env = let tcg_env' = (last_tcg_env `addTcgDUs` src_dus)
in
tcg_env' { tcg_warns = tcg_warns tcg_env' `plusWarns` rn_warns };
} ;
traceRn (text "finish rnSrc" <+> ppr rn_group) ;
traceRn (text "finish Dus" <+> ppr src_dus ) ;
return (final_tcg_env, rn_group)
}}}}
inNewEnv :: TcM TcGblEnv -> (TcGblEnv -> TcM a) -> TcM a
inNewEnv env cont = do e <- env
setGblEnv e $ cont e
addTcgDUs :: TcGblEnv -> DefUses -> TcGblEnv
addTcgDUs tcg_env dus = tcg_env { tcg_dus = tcg_dus tcg_env `plusDU` dus }
rnList :: (a -> RnM (b, FreeVars)) -> [Located a] -> RnM ([Located b], FreeVars)
rnList f xs = mapFvRn (wrapLocFstM f) xs
\end{code}
%*********************************************************
%* *
HsDoc stuff
%* *
%*********************************************************
\begin{code}
rnDocDecl :: DocDecl -> RnM DocDecl
rnDocDecl (DocCommentNext doc) = do
rn_doc <- rnHsDoc doc
return (DocCommentNext rn_doc)
rnDocDecl (DocCommentPrev doc) = do
rn_doc <- rnHsDoc doc
return (DocCommentPrev rn_doc)
rnDocDecl (DocCommentNamed str doc) = do
rn_doc <- rnHsDoc doc
return (DocCommentNamed str rn_doc)
rnDocDecl (DocGroup lev doc) = do
rn_doc <- rnHsDoc doc
return (DocGroup lev rn_doc)
\end{code}
%*********************************************************
%* *
Source-code fixity declarations
%* *
%*********************************************************
\begin{code}
rnSrcFixityDecls :: NameSet -> [LFixitySig RdrName] -> RnM [LFixitySig Name]
rnSrcFixityDecls bndr_set fix_decls
= do fix_decls <- mapM rn_decl fix_decls
return (concat fix_decls)
where
rn_decl :: LFixitySig RdrName -> RnM [LFixitySig Name]
rn_decl (L loc (FixitySig (L name_loc rdr_name) fixity))
= setSrcSpan name_loc $
do names <- lookupLocalDataTcNames bndr_set what rdr_name
return [ L loc (FixitySig (L name_loc name) fixity)
| name <- names ]
what = ptext (sLit "fixity signature")
\end{code}
%*********************************************************
%* *
Source-code deprecations declarations
%* *
%*********************************************************
Check that the deprecated names are defined, are defined locally, and
that there are no duplicate deprecations.
It's only imported deprecations, dealt with in RnIfaces, that we
gather them together.
\begin{code}
rnSrcWarnDecls :: NameSet -> [LWarnDecl RdrName] -> RnM Warnings
rnSrcWarnDecls _ []
= return NoWarnings
rnSrcWarnDecls bndr_set decls
= do {
; mapM_ (\ dups -> let (L loc rdr:lrdr':_) = dups
in addErrAt loc (dupWarnDecl lrdr' rdr))
warn_rdr_dups
; pairs_s <- mapM (addLocM rn_deprec) decls
; return (WarnSome ((concat pairs_s))) }
where
rn_deprec (Warning rdr_name txt)
= do { names <- lookupLocalDataTcNames bndr_set what rdr_name
; return [(nameOccName name, txt) | name <- names] }
what = ptext (sLit "deprecation")
warn_rdr_dups = findDupRdrNames (map (\ (L loc (Warning rdr_name _)) -> L loc rdr_name) decls)
findDupRdrNames :: [Located RdrName] -> [[Located RdrName]]
findDupRdrNames = findDupsEq (\ x -> \ y -> rdrNameOcc (unLoc x) == rdrNameOcc (unLoc y))
dupWarnDecl :: Located RdrName -> RdrName -> SDoc
dupWarnDecl (L loc _) rdr_name
= vcat [ptext (sLit "Multiple warning declarations for") <+> quotes (ppr rdr_name),
ptext (sLit "also at ") <+> ppr loc]
\end{code}
%*********************************************************
%* *
\subsection{Annotation declarations}
%* *
%*********************************************************
\begin{code}
rnAnnDecl :: AnnDecl RdrName -> RnM (AnnDecl Name, FreeVars)
rnAnnDecl (HsAnnotation provenance expr) = do
(provenance', provenance_fvs) <- rnAnnProvenance provenance
(expr', expr_fvs) <- rnLExpr expr
return (HsAnnotation provenance' expr', provenance_fvs `plusFV` expr_fvs)
rnAnnProvenance :: AnnProvenance RdrName -> RnM (AnnProvenance Name, FreeVars)
rnAnnProvenance provenance = do
provenance' <- modifyAnnProvenanceNameM lookupTopBndrRn provenance
return (provenance', maybe emptyFVs unitFV (annProvenanceName_maybe provenance'))
\end{code}
%*********************************************************
%* *
\subsection{Default declarations}
%* *
%*********************************************************
\begin{code}
rnDefaultDecl :: DefaultDecl RdrName -> RnM (DefaultDecl Name, FreeVars)
rnDefaultDecl (DefaultDecl tys)
= do { (tys', fvs) <- mapFvRn (rnHsTypeFVs doc_str) tys
; return (DefaultDecl tys', fvs) }
where
doc_str = DefaultDeclCtx
\end{code}
%*********************************************************
%* *
\subsection{Foreign declarations}
%* *
%*********************************************************
\begin{code}
rnHsForeignDecl :: ForeignDecl RdrName -> RnM (ForeignDecl Name, FreeVars)
rnHsForeignDecl (ForeignImport name ty _ spec)
= do { topEnv :: HscEnv <- getTopEnv
; name' <- lookupLocatedTopBndrRn name
; (ty', fvs) <- rnHsTypeFVs (ForeignDeclCtx name) ty
; let packageId = thisPackage $ hsc_dflags topEnv
spec' = patchForeignImport packageId spec
; return (ForeignImport name' ty' noForeignImportCoercionYet spec', fvs) }
rnHsForeignDecl (ForeignExport name ty _ spec)
= do { name' <- lookupLocatedOccRn name
; (ty', fvs) <- rnHsTypeFVs (ForeignDeclCtx name) ty
; return (ForeignExport name' ty' noForeignExportCoercionYet spec, fvs `addOneFV` unLoc name') }
patchForeignImport :: PackageId -> ForeignImport -> ForeignImport
patchForeignImport packageId (CImport cconv safety fs spec)
= CImport cconv safety fs (patchCImportSpec packageId spec)
patchCImportSpec :: PackageId -> CImportSpec -> CImportSpec
patchCImportSpec packageId spec
= case spec of
CFunction callTarget -> CFunction $ patchCCallTarget packageId callTarget
_ -> spec
patchCCallTarget :: PackageId -> CCallTarget -> CCallTarget
patchCCallTarget packageId callTarget
= case callTarget of
StaticTarget label Nothing
-> StaticTarget label (Just packageId)
_ -> callTarget
\end{code}
%*********************************************************
%* *
\subsection{Instance declarations}
%* *
%*********************************************************
\begin{code}
rnSrcInstDecl :: InstDecl RdrName -> RnM (InstDecl Name, FreeVars)
rnSrcInstDecl (InstDecl inst_ty mbinds uprags ats)
= do { inst_ty' <- rnLHsInstType (text "In an instance declaration") inst_ty
; let Just (inst_tyvars, _, L _ cls,_) = splitLHsInstDeclTy_maybe inst_ty'
; (mbinds', meth_fvs) <- extendTyVarEnvForMethodBinds inst_tyvars $
rnMethodBinds cls (\_ -> [])
mbinds
; (ats', at_fvs) <- extendTyVarEnvFVRn (map hsLTyVarName inst_tyvars) $
rnATInsts cls ats
; let binders = collectHsBindsBinders mbinds'
; uprags' <- bindLocalNames binders $
renameSigs (InstDeclCtxt cls) uprags
; return (InstDecl inst_ty' mbinds' uprags' ats',
meth_fvs `plusFV` at_fvs
`plusFV` hsSigsFVs uprags'
`plusFV` extractHsTyNames inst_ty') }
\end{code}
Renaming of the associated types in instances.
\begin{code}
rnATInsts :: Name -> [LTyClDecl RdrName] -> RnM ([LTyClDecl Name], FreeVars)
rnATInsts cls atDecls = rnList rnATInst atDecls
where
rnATInst tydecl@TyData {} = rnTyClDecl (Just cls) tydecl
rnATInst tydecl@TySynonym {} = rnTyClDecl (Just cls) tydecl
rnATInst tydecl = pprPanic "RnSource.rnATInsts: invalid AT instance"
(ppr (tcdName tydecl))
\end{code}
For the method bindings in class and instance decls, we extend the
type variable environment iff -fglasgow-exts
\begin{code}
extendTyVarEnvForMethodBinds :: [LHsTyVarBndr Name]
-> RnM (Bag (LHsBind Name), FreeVars)
-> RnM (Bag (LHsBind Name), FreeVars)
extendTyVarEnvForMethodBinds tyvars thing_inside
= do { scoped_tvs <- xoptM Opt_ScopedTypeVariables
; if scoped_tvs then
extendTyVarEnvFVRn (map hsLTyVarName tyvars) thing_inside
else
thing_inside }
\end{code}
%*********************************************************
%* *
\subsection{Stand-alone deriving declarations}
%* *
%*********************************************************
\begin{code}
rnSrcDerivDecl :: DerivDecl RdrName -> RnM (DerivDecl Name, FreeVars)
rnSrcDerivDecl (DerivDecl ty)
= do { standalone_deriv_ok <- xoptM Opt_StandaloneDeriving
; unless standalone_deriv_ok (addErr standaloneDerivErr)
; ty' <- rnLHsInstType (text "In a deriving declaration") ty
; let fvs = extractHsTyNames ty'
; return (DerivDecl ty', fvs) }
standaloneDerivErr :: SDoc
standaloneDerivErr
= hang (ptext (sLit "Illegal standalone deriving declaration"))
2 (ptext (sLit "Use -XStandaloneDeriving to enable this extension"))
\end{code}
%*********************************************************
%* *
\subsection{Rules}
%* *
%*********************************************************
\begin{code}
rnHsRuleDecl :: RuleDecl RdrName -> RnM (RuleDecl Name, FreeVars)
rnHsRuleDecl (HsRule rule_name act vars lhs _fv_lhs rhs _fv_rhs)
= bindPatSigTyVarsFV (collectRuleBndrSigTys vars) $
bindLocatedLocalsFV (map get_var vars) $ \ ids ->
do { (vars', fv_vars) <- mapFvRn rn_var (vars `zip` ids)
; (lhs', fv_lhs') <- rnLExpr lhs
; (rhs', fv_rhs') <- rnLExpr rhs
; checkValidRule rule_name ids lhs' fv_lhs'
; return (HsRule rule_name act vars' lhs' fv_lhs' rhs' fv_rhs',
fv_vars `plusFV` fv_lhs' `plusFV` fv_rhs') }
where
doc = RuleCtx rule_name
get_var (RuleBndr v) = v
get_var (RuleBndrSig v _) = v
rn_var (RuleBndr (L loc _), id)
= return (RuleBndr (L loc id), emptyFVs)
rn_var (RuleBndrSig (L loc _) t, id)
= do { (t', fvs) <- rnHsTypeFVs doc t
; return (RuleBndrSig (L loc id) t', fvs) }
badRuleVar :: FastString -> Name -> SDoc
badRuleVar name var
= sep [ptext (sLit "Rule") <+> doubleQuotes (ftext name) <> colon,
ptext (sLit "Forall'd variable") <+> quotes (ppr var) <+>
ptext (sLit "does not appear on left hand side")]
\end{code}
Note [Rule LHS validity checking]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Check the shape of a transformation rule LHS. Currently we only allow
LHSs of the form @(f e1 .. en)@, where @f@ is not one of the
@forall@'d variables.
We used restrict the form of the 'ei' to prevent you writing rules
with LHSs with a complicated desugaring (and hence unlikely to match);
(e.g. a case expression is not allowed: too elaborate.)
But there are legitimate non-trivial args ei, like sections and
lambdas. So it seems simmpler not to check at all, and that is why
check_e is commented out.
\begin{code}
checkValidRule :: FastString -> [Name] -> LHsExpr Name -> NameSet -> RnM ()
checkValidRule rule_name ids lhs' fv_lhs'
= do {
case (validRuleLhs ids lhs') of
Nothing -> return ()
Just bad -> failWithTc (badRuleLhsErr rule_name lhs' bad)
; let bad_vars = [var | var <- ids, not (var `elemNameSet` fv_lhs')]
; mapM_ (addErr . badRuleVar rule_name) bad_vars }
validRuleLhs :: [Name] -> LHsExpr Name -> Maybe (HsExpr Name)
validRuleLhs foralls lhs
= checkl lhs
where
checkl (L _ e) = check e
check (OpApp e1 op _ e2) = checkl op `mplus` checkl_e e1 `mplus` checkl_e e2
check (HsApp e1 e2) = checkl e1 `mplus` checkl_e e2
check (HsVar v) | v `notElem` foralls = Nothing
check other = Just other
checkl_e (L _ _e) = Nothing
badRuleLhsErr :: FastString -> LHsExpr Name -> HsExpr Name -> SDoc
badRuleLhsErr name lhs bad_e
= sep [ptext (sLit "Rule") <+> ftext name <> colon,
nest 4 (vcat [ptext (sLit "Illegal expression:") <+> ppr bad_e,
ptext (sLit "in left-hand side:") <+> ppr lhs])]
$$
ptext (sLit "LHS must be of form (f e1 .. en) where f is not forall'd")
\end{code}
%*********************************************************
%* *
\subsection{Vectorisation declarations}
%* *
%*********************************************************
\begin{code}
rnHsVectDecl :: VectDecl RdrName -> RnM (VectDecl Name, FreeVars)
rnHsVectDecl (HsVect var Nothing)
= do { var' <- lookupLocatedOccRn var
; return (HsVect var' Nothing, unitFV (unLoc var'))
}
rnHsVectDecl (HsVect var (Just rhs@(L _ (HsVar _))))
= do { var' <- lookupLocatedOccRn var
; (rhs', fv_rhs) <- rnLExpr rhs
; return (HsVect var' (Just rhs'), fv_rhs `addOneFV` unLoc var')
}
rnHsVectDecl (HsVect _var (Just _rhs))
= failWith $ vcat
[ ptext (sLit "IMPLEMENTATION RESTRICTION: right-hand side of a VECTORISE pragma")
, ptext (sLit "must be an identifier")
]
rnHsVectDecl (HsNoVect var)
= do { var' <- lookupLocatedTopBndrRn var
; return (HsNoVect var', unitFV (unLoc var'))
}
rnHsVectDecl (HsVectTypeIn isScalar tycon Nothing)
= do { tycon' <- lookupLocatedOccRn tycon
; return (HsVectTypeIn isScalar tycon' Nothing, unitFV (unLoc tycon'))
}
rnHsVectDecl (HsVectTypeIn isScalar tycon (Just rhs_tycon))
= do { tycon' <- lookupLocatedOccRn tycon
; rhs_tycon' <- lookupLocatedOccRn rhs_tycon
; return ( HsVectTypeIn isScalar tycon' (Just rhs_tycon')
, mkFVs [unLoc tycon', unLoc rhs_tycon'])
}
rnHsVectDecl (HsVectTypeOut _ _ _)
= panic "RnSource.rnHsVectDecl: Unexpected 'HsVectTypeOut'"
rnHsVectDecl (HsVectClassIn cls)
= do { cls' <- lookupLocatedOccRn cls
; return (HsVectClassIn cls', unitFV (unLoc cls'))
}
rnHsVectDecl (HsVectClassOut _)
= panic "RnSource.rnHsVectDecl: Unexpected 'HsVectClassOut'"
rnHsVectDecl (HsVectInstIn instTy)
= do { instTy' <- rnLHsInstType (text "In a VECTORISE pragma") instTy
; return (HsVectInstIn instTy', extractHsTyNames instTy')
}
rnHsVectDecl (HsVectInstOut _)
= panic "RnSource.rnHsVectDecl: Unexpected 'HsVectInstOut'"
\end{code}
%*********************************************************
%* *
\subsection{Type, class and iface sig declarations}
%* *
%*********************************************************
@rnTyDecl@ uses the `global name function' to create a new type
declaration in which local names have been replaced by their original
names, reporting any unknown names.
Renaming type variables is a pain. Because they now contain uniques,
it is necessary to pass in an association list which maps a parsed
tyvar to its @Name@ representation.
In some cases (type signatures of values),
it is even necessary to go over the type first
in order to get the set of tyvars used by it, make an assoc list,
and then go over it again to rename the tyvars!
However, we can also do some scoping checks at the same time.
Note [Extra dependencies from .hs-boot files]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Consider the following case:
module A where
import B
data A1 = A1 B1
module B where
import {-# SOURCE #-} A
type DisguisedA1 = A1
data B1 = B1 DisguisedA1
We do not follow type synonyms when building the dependencies for each datatype,
so we will not find out that B1 really depends on A1 (which means it depends on
itself). To handle this problem, at the moment we add dependencies to everything
that comes from an .hs-boot file. But we don't add those dependencies to
everything. Imagine module B above had another datatype declaration:
data B2 = B2 Int
Even though B2 has a dependency (on Int), all its dependencies are from things
that live on other packages. Since we don't have mutual dependencies across
packages, it is safe not to add the dependencies on the .hs-boot stuff to B2.
See also Note [Grouping of type and class declarations] in TcTyClsDecls.
\begin{code}
isInPackage :: PackageId -> Name -> Bool
isInPackage pkgId nm = case nameModule_maybe nm of
Nothing -> False
Just m -> pkgId == modulePackageId m
rnTyClDecls :: [Name] -> [[LTyClDecl RdrName]]
-> RnM ([[LTyClDecl Name]], FreeVars)
rnTyClDecls extra_deps tycl_ds
= do { ds_w_fvs <- mapM (wrapLocFstM (rnTyClDecl Nothing)) (concat tycl_ds)
; thisPkg <- fmap thisPackage getDOpts
; let add_boot_deps :: FreeVars -> FreeVars
add_boot_deps fvs | any (isInPackage thisPkg) (nameSetToList fvs)
= fvs `plusFV` mkFVs extra_deps
| otherwise
= fvs
ds_w_fvs' = map (\(ds, fvs) -> (ds, add_boot_deps fvs)) ds_w_fvs
sccs :: [SCC (LTyClDecl Name)]
sccs = depAnalTyClDecls ds_w_fvs'
all_fvs = foldr (plusFV . snd) emptyFVs ds_w_fvs'
; return (map flattenSCC sccs, all_fvs) }
rnTyClDecl :: Maybe Name
-> TyClDecl RdrName
-> RnM (TyClDecl Name, FreeVars)
rnTyClDecl _ (ForeignType {tcdLName = name, tcdExtName = ext_name})
= do { name' <- lookupLocatedTopBndrRn name
; return (ForeignType {tcdLName = name', tcdExtName = ext_name},
emptyFVs) }
rnTyClDecl mb_cls (TyFamily { tcdLName = tycon, tcdTyVars = tyvars
, tcdFlavour = flav, tcdKind = kind })
= bindQTvs fmly_doc mb_cls tyvars $ \tyvars' ->
do { tycon' <- lookupLocatedTopBndrRn tycon
; kind' <- rnLHsMaybeKind fmly_doc kind
; let fv_kind = maybe emptyFVs extractHsTyNames kind'
fvs = extractHsTyVarBndrNames_s tyvars' fv_kind
; return ( TyFamily { tcdLName = tycon', tcdTyVars = tyvars'
, tcdFlavour = flav, tcdKind = kind' }
, fvs) }
where fmly_doc = TyFamilyCtx tycon
rnTyClDecl mb_cls tydecl@TyData {tcdND = new_or_data, tcdCtxt = context,
tcdLName = tycon, tcdTyVars = tyvars,
tcdTyPats = typats, tcdCons = condecls,
tcdKindSig = sig, tcdDerivs = derivs}
= do { tycon' <- lookupTcdName mb_cls tydecl
; sig' <- rnLHsMaybeKind data_doc sig
; checkTc (h98_style || null (unLoc context))
(badGadtStupidTheta tycon)
; ((tyvars', context', typats', derivs'), stuff_fvs)
<- bindQTvs data_doc mb_cls tyvars $ \ tyvars' -> do
{ context' <- rnContext data_doc context
; (typats', fvs1) <- rnTyPats data_doc tycon' typats
; (derivs', fvs2) <- rn_derivs derivs
; let fvs = fvs1 `plusFV` fvs2 `plusFV`
extractHsCtxtTyNames context'
`plusFV` maybe emptyFVs extractHsTyNames sig'
; return ((tyvars', context', typats', derivs'), fvs) }
; let tc_tvs_in_scope | h98_style = hsLTyVarNames tyvars'
| otherwise = []
; (condecls', con_fvs) <- bindLocalNamesFV tc_tvs_in_scope $
rnConDecls condecls
; return (TyData {tcdND = new_or_data, tcdCtxt = context',
tcdLName = tycon', tcdTyVars = tyvars',
tcdTyPats = typats', tcdKindSig = sig',
tcdCons = condecls', tcdDerivs = derivs'},
con_fvs `plusFV` stuff_fvs)
}
where
h98_style = case condecls of
L _ (ConDecl { con_res = ResTyGADT {} }) : _ -> False
_ -> True
data_doc = TyDataCtx tycon
rn_derivs Nothing = return (Nothing, emptyFVs)
rn_derivs (Just ds) = do { ds' <- rnLHsTypes data_doc ds
; return (Just ds', extractHsTyNames_s ds') }
rnTyClDecl mb_cls tydecl@(TySynonym { tcdTyVars = tyvars, tcdLName = name,
tcdTyPats = typats, tcdSynRhs = ty})
= bindQTvs syn_doc mb_cls tyvars $ \ tyvars' -> do
{
name' <- lookupTcdName mb_cls tydecl
; (typats',fvs1) <- rnTyPats syn_doc name' typats
; (ty', fvs2) <- rnHsTypeFVs syn_doc ty
; return (TySynonym { tcdLName = name', tcdTyVars = tyvars'
, tcdTyPats = typats', tcdSynRhs = ty'}
, extractHsTyVarBndrNames_s tyvars' (fvs1 `plusFV` fvs2)) }
where
syn_doc = TySynCtx name
rnTyClDecl _ (ClassDecl {tcdCtxt = context, tcdLName = lcls,
tcdTyVars = tyvars, tcdFDs = fds, tcdSigs = sigs,
tcdMeths = mbinds, tcdATs = ats, tcdATDefs = at_defs,
tcdDocs = docs})
= do { lcls' <- lookupLocatedTopBndrRn lcls
; let cls' = unLoc lcls'
; ((tyvars', context', fds', ats', at_defs', sigs'), stuff_fvs)
<- bindTyVarsFV cls_doc tyvars $ \ tyvars' -> do
{ context' <- rnContext cls_doc context
; fds' <- rnFds (docOfHsDocContext cls_doc) fds
; let rn_at = rnTyClDecl (Just cls')
; (ats', fv_ats) <- mapAndUnzipM (wrapLocFstM rn_at) ats
; sigs' <- renameSigs (ClsDeclCtxt cls') sigs
; (at_defs', fv_at_defs) <- mapAndUnzipM (wrapLocFstM rn_at) at_defs
; let fvs = extractHsCtxtTyNames context' `plusFV`
hsSigsFVs sigs' `plusFV`
plusFVs fv_ats `plusFV`
plusFVs fv_at_defs
; return ((tyvars', context', fds', ats', at_defs', sigs'), fvs) }
; let sig_rdr_names_w_locs = [op | L _ (TypeSig ops _) <- sigs, op <- ops]
; checkDupRdrNames sig_rdr_names_w_locs
; (mbinds', meth_fvs)
<- extendTyVarEnvForMethodBinds tyvars' $
rnMethodBinds cls' (mkSigTvFn sigs') mbinds
; docs' <- mapM (wrapLocM rnDocDecl) docs
; return (ClassDecl { tcdCtxt = context', tcdLName = lcls',
tcdTyVars = tyvars', tcdFDs = fds', tcdSigs = sigs',
tcdMeths = mbinds', tcdATs = ats', tcdATDefs = at_defs',
tcdDocs = docs'},
extractHsTyVarBndrNames_s tyvars' (meth_fvs `plusFV` stuff_fvs)) }
where
cls_doc = ClassDeclCtx lcls
bindQTvs :: HsDocContext -> Maybe Name -> [LHsTyVarBndr RdrName]
-> ([LHsTyVarBndr Name] -> RnM (a, FreeVars))
-> RnM (a, FreeVars)
bindQTvs doc mb_cls tyvars thing_inside
| isNothing mb_cls
= bindTyVarsFV doc tyvars thing_inside
| otherwise
= do { let tv_rdr_names = map hsLTyVarLocName tyvars
; mapM_ dupBoundTyVar (findDupRdrNames tv_rdr_names)
; rdr_env <- getLocalRdrEnv
; tv_ns <- mapM (mk_tv_name rdr_env) tv_rdr_names
; tyvars' <- zipWithM (\old new -> replaceLTyVarName old new (rnLHsKind doc)) tyvars tv_ns
; (thing, fvs) <- bindLocalNamesFV tv_ns $ thing_inside tyvars'
; let bad_tvs = filterNameSet (isTvOcc . nameOccName) fvs
; unless (isEmptyNameSet bad_tvs) (badAssocRhs (nameSetToList bad_tvs))
; return (thing, fvs) }
where
mk_tv_name :: LocalRdrEnv -> Located RdrName -> RnM Name
mk_tv_name rdr_env (L l tv_rdr)
= case lookupLocalRdrEnv rdr_env tv_rdr of
Just n -> return n
Nothing -> newLocalBndrRn (L l tv_rdr)
badAssocRhs :: [Name] -> RnM ()
badAssocRhs ns
= addErr (hang (ptext (sLit "The RHS of an associated type declaration mentions type variable")
<> plural ns
<+> pprWithCommas (quotes . ppr) ns)
2 (ptext (sLit "All such variables must be bound on the LHS")))
dupBoundTyVar :: [Located RdrName] -> RnM ()
dupBoundTyVar (L loc tv : _)
= setSrcSpan loc $
addErr (ptext (sLit "Illegal repeated type variable") <+> quotes (ppr tv))
dupBoundTyVar [] = panic "dupBoundTyVar"
badGadtStupidTheta :: Located RdrName -> SDoc
badGadtStupidTheta _
= vcat [ptext (sLit "No context is allowed on a GADT-style data declaration"),
ptext (sLit "(You can put a context on each contructor, though.)")]
\end{code}
Note [Stupid theta]
~~~~~~~~~~~~~~~~~~~
Trac #3850 complains about a regression wrt 6.10 for
data Show a => T a
There is no reason not to allow the stupid theta if there are no data
constructors. It's still stupid, but does no harm, and I don't want
to cause programs to break unnecessarily (notably HList). So if there
are no data constructors we allow h98_style = True
\begin{code}
depAnalTyClDecls :: [(LTyClDecl Name, FreeVars)] -> [SCC (LTyClDecl Name)]
depAnalTyClDecls ds_w_fvs
= stronglyConnCompFromEdgedVertices edges
where
edges = [ (d, tcdName (unLoc d), map get_assoc (nameSetToList fvs))
| (d, fvs) <- ds_w_fvs ]
get_assoc n = lookupNameEnv assoc_env n `orElse` n
assoc_env = mkNameEnv assoc_env_list
assoc_env_list = do
(L _ d, _) <- ds_w_fvs
case d of
ClassDecl { tcdLName = L _ cls_name
, tcdATs = ats } -> do
L _ assoc_decl <- ats
return (tcdName assoc_decl, cls_name)
TyData { tcdLName = L _ data_name
, tcdCons = cons } -> do
L _ dc <- cons
return (unLoc (con_name dc), data_name)
_ -> []
\end{code}
Note [Dependency analysis of type and class decls]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
We need to do dependency analysis on type and class declarations
else we get bad error messages. Consider
data T f a = MkT f a
data S f a = MkS f (T f a)
This has a kind error, but the error message is better if you
check T first, (fixing its kind) and *then* S. If you do kind
inference together, you might get an error reported in S, which
is jolly confusing. See Trac #4875
%*********************************************************
%* *
\subsection{Support code for type/data declarations}
%* *
%*********************************************************
\begin{code}
rnTyPats :: HsDocContext -> Located Name -> Maybe [LHsType RdrName] -> RnM (Maybe [LHsType Name], FreeVars)
rnTyPats _ _ Nothing
= return (Nothing, emptyFVs)
rnTyPats doc tc (Just typats)
= do { typats' <- rnLHsTypes doc typats
; let fvs = addOneFV (extractHsTyNames_s typats') (unLoc tc)
; return (Just typats', fvs) }
rnConDecls :: [LConDecl RdrName] -> RnM ([LConDecl Name], FreeVars)
rnConDecls condecls
= do { condecls' <- mapM (wrapLocM rnConDecl) condecls
; return (condecls', plusFVs (map conDeclFVs condecls')) }
rnConDecl :: ConDecl RdrName -> RnM (ConDecl Name)
rnConDecl decl@(ConDecl { con_name = name, con_qvars = tvs
, con_cxt = cxt, con_details = details
, con_res = res_ty, con_doc = mb_doc
, con_old_rec = old_rec, con_explicit = expl })
= do { addLocM checkConName name
; when old_rec (addWarn (deprecRecSyntax decl))
; new_name <- lookupLocatedTopBndrRn name
; rdr_env <- getLocalRdrEnv
; let in_scope = (`elemLocalRdrEnv` rdr_env) . unLoc
arg_tys = hsConDeclArgTys details
mentioned_tvs = case res_ty of
ResTyH98 -> filterOut in_scope (get_rdr_tvs arg_tys)
ResTyGADT ty -> get_rdr_tvs (ty : arg_tys)
; new_tvs <- case expl of
Implicit -> return (userHsTyVarBndrs mentioned_tvs)
Explicit -> do { warnUnusedForAlls (docOfHsDocContext doc) tvs mentioned_tvs
; return tvs }
; mb_doc' <- rnMbLHsDoc mb_doc
; bindTyVarsRn doc new_tvs $ \new_tyvars -> do
{ new_context <- rnContext doc cxt
; new_details <- rnConDeclDetails doc details
; (new_details', new_res_ty) <- rnConResult doc new_details res_ty
; return (decl { con_name = new_name, con_qvars = new_tyvars, con_cxt = new_context
, con_details = new_details', con_res = new_res_ty, con_doc = mb_doc' }) }}
where
doc = ConDeclCtx name
get_rdr_tvs tys = extractHsRhoRdrTyVars cxt (noLoc (HsTupleTy HsBoxedTuple tys))
rnConResult :: HsDocContext
-> HsConDetails (LHsType Name) [ConDeclField Name]
-> ResType RdrName
-> RnM (HsConDetails (LHsType Name) [ConDeclField Name],
ResType Name)
rnConResult _ details ResTyH98 = return (details, ResTyH98)
rnConResult doc details (ResTyGADT ty)
= do { ty' <- rnLHsType doc ty
; let (arg_tys, res_ty) = splitHsFunType ty'
details' = case details of
RecCon {} -> details
PrefixCon {} -> PrefixCon arg_tys
InfixCon {} -> pprPanic "rnConResult" (ppr ty)
; when (not (null arg_tys) && case details of { RecCon {} -> True; _ -> False })
(addErr (badRecResTy (docOfHsDocContext doc)))
; return (details', ResTyGADT res_ty) }
rnConDeclDetails :: HsDocContext
-> HsConDetails (LHsType RdrName) [ConDeclField RdrName]
-> RnM (HsConDetails (LHsType Name) [ConDeclField Name])
rnConDeclDetails doc (PrefixCon tys)
= do { new_tys <- mapM (rnLHsType doc) tys
; return (PrefixCon new_tys) }
rnConDeclDetails doc (InfixCon ty1 ty2)
= do { new_ty1 <- rnLHsType doc ty1
; new_ty2 <- rnLHsType doc ty2
; return (InfixCon new_ty1 new_ty2) }
rnConDeclDetails doc (RecCon fields)
= do { new_fields <- rnConDeclFields doc fields
; return (RecCon new_fields) }
deprecRecSyntax :: ConDecl RdrName -> SDoc
deprecRecSyntax decl
= vcat [ ptext (sLit "Declaration of") <+> quotes (ppr (con_name decl))
<+> ptext (sLit "uses deprecated syntax")
, ptext (sLit "Instead, use the form")
, nest 2 (ppr decl) ]
badRecResTy :: SDoc -> SDoc
badRecResTy doc = ptext (sLit "Malformed constructor signature") $$ doc
checkConName :: RdrName -> TcRn ()
checkConName name = checkErr (isRdrDataCon name) (badDataCon name)
badDataCon :: RdrName -> SDoc
badDataCon name
= hsep [ptext (sLit "Illegal data constructor name"), quotes (ppr name)]
\end{code}
%*********************************************************
%* *
\subsection{Support code for type/data declarations}
%* *
%*********************************************************
Get the mapping from constructors to fields for this module.
It's convenient to do this after the data type decls have been renamed
\begin{code}
extendRecordFieldEnv :: [[LTyClDecl RdrName]] -> [LInstDecl RdrName] -> TcM TcGblEnv
extendRecordFieldEnv tycl_decls inst_decls
= do { tcg_env <- getGblEnv
; field_env' <- foldrM get_con (tcg_field_env tcg_env) all_data_cons
; return (tcg_env { tcg_field_env = field_env' }) }
where
lookup x = do { x' <- lookupLocatedTopBndrRn x
; return $ unLoc x'}
all_data_cons :: [ConDecl RdrName]
all_data_cons = [con | L _ (TyData { tcdCons = cons }) <- all_tycl_decls
, L _ con <- cons ]
all_tycl_decls = at_tycl_decls ++ concat tycl_decls
at_tycl_decls = instDeclATs inst_decls
get_con (ConDecl { con_name = con, con_details = RecCon flds })
(RecFields env fld_set)
= do { con' <- lookup con
; flds' <- mapM lookup (map cd_fld_name flds)
; let env' = extendNameEnv env con' flds'
fld_set' = addListToNameSet fld_set flds'
; return $ (RecFields env' fld_set') }
get_con _ env = return env
\end{code}
%*********************************************************
%* *
\subsection{Support code to rename types}
%* *
%*********************************************************
\begin{code}
rnFds :: SDoc -> [Located (FunDep RdrName)] -> RnM [Located (FunDep Name)]
rnFds doc fds
= mapM (wrapLocM rn_fds) fds
where
rn_fds (tys1, tys2)
= do { tys1' <- rnHsTyVars doc tys1
; tys2' <- rnHsTyVars doc tys2
; return (tys1', tys2') }
rnHsTyVars :: SDoc -> [RdrName] -> RnM [Name]
rnHsTyVars doc tvs = mapM (rnHsTyVar doc) tvs
rnHsTyVar :: SDoc -> RdrName -> RnM Name
rnHsTyVar _doc tyvar = lookupOccRn tyvar
\end{code}
%*********************************************************
%* *
findSplice
%* *
%*********************************************************
This code marches down the declarations, looking for the first
Template Haskell splice. As it does so it
a) groups the declarations into a HsGroup
b) runs any top-level quasi-quotes
\begin{code}
findSplice :: [LHsDecl RdrName] -> RnM (HsGroup RdrName, Maybe (SpliceDecl RdrName, [LHsDecl RdrName]))
findSplice ds = addl emptyRdrGroup ds
addl :: HsGroup RdrName -> [LHsDecl RdrName]
-> RnM (HsGroup RdrName, Maybe (SpliceDecl RdrName, [LHsDecl RdrName]))
addl gp [] = return (gp, Nothing)
addl gp (L l d : ds) = add gp l d ds
add :: HsGroup RdrName -> SrcSpan -> HsDecl RdrName -> [LHsDecl RdrName]
-> RnM (HsGroup RdrName, Maybe (SpliceDecl RdrName, [LHsDecl RdrName]))
add gp loc (SpliceD splice@(SpliceDecl _ flag)) ds
= do {
case flag of
Explicit -> return ()
Implicit -> do { th_on <- xoptM Opt_TemplateHaskell
; unless th_on $ setSrcSpan loc $
failWith badImplicitSplice }
; return (gp, Just (splice, ds)) }
where
badImplicitSplice = ptext (sLit "Parse error: naked expression at top level")
#ifndef GHCI
add _ _ (QuasiQuoteD qq) _
= pprPanic "Can't do QuasiQuote declarations without GHCi" (ppr qq)
#else
add gp _ (QuasiQuoteD qq) ds
= do { ds' <- runQuasiQuoteDecl qq
; addl gp (ds' ++ ds) }
#endif
add gp@(HsGroup {hs_tyclds = ts, hs_fixds = fs}) l (TyClD d) ds
| isClassDecl d
= let fsigs = [ L l f | L l (FixSig f) <- tcdSigs d ] in
addl (gp { hs_tyclds = add_tycld (L l d) ts, hs_fixds = fsigs ++ fs}) ds
| otherwise
= addl (gp { hs_tyclds = add_tycld (L l d) ts }) ds
add gp@(HsGroup {hs_fixds = ts}) l (SigD (FixSig f)) ds
= addl (gp {hs_fixds = L l f : ts}) ds
add gp@(HsGroup {hs_valds = ts}) l (SigD d) ds
= addl (gp {hs_valds = add_sig (L l d) ts}) ds
add gp@(HsGroup {hs_valds = ts}) l (ValD d) ds
= addl (gp { hs_valds = add_bind (L l d) ts }) ds
add gp@(HsGroup {hs_instds = ts}) l (InstD d) ds
= addl (gp { hs_instds = L l d : ts }) ds
add gp@(HsGroup {hs_derivds = ts}) l (DerivD d) ds
= addl (gp { hs_derivds = L l d : ts }) ds
add gp@(HsGroup {hs_defds = ts}) l (DefD d) ds
= addl (gp { hs_defds = L l d : ts }) ds
add gp@(HsGroup {hs_fords = ts}) l (ForD d) ds
= addl (gp { hs_fords = L l d : ts }) ds
add gp@(HsGroup {hs_warnds = ts}) l (WarningD d) ds
= addl (gp { hs_warnds = L l d : ts }) ds
add gp@(HsGroup {hs_annds = ts}) l (AnnD d) ds
= addl (gp { hs_annds = L l d : ts }) ds
add gp@(HsGroup {hs_ruleds = ts}) l (RuleD d) ds
= addl (gp { hs_ruleds = L l d : ts }) ds
add gp@(HsGroup {hs_vects = ts}) l (VectD d) ds
= addl (gp { hs_vects = L l d : ts }) ds
add gp l (DocD d) ds
= addl (gp { hs_docs = (L l d) : (hs_docs gp) }) ds
add_tycld :: LTyClDecl a -> [[LTyClDecl a]] -> [[LTyClDecl a]]
add_tycld d [] = [[d]]
add_tycld d (ds:dss) = (d:ds) : dss
add_bind :: LHsBind a -> HsValBinds a -> HsValBinds a
add_bind b (ValBindsIn bs sigs) = ValBindsIn (bs `snocBag` b) sigs
add_bind _ (ValBindsOut {}) = panic "RdrHsSyn:add_bind"
add_sig :: LSig a -> HsValBinds a -> HsValBinds a
add_sig s (ValBindsIn bs sigs) = ValBindsIn bs (s:sigs)
add_sig _ (ValBindsOut {}) = panic "RdrHsSyn:add_sig"
\end{code}