\section[RnSource]{Main pass of renamer}
\begin{code}
-module RnSource ( rnDecl, rnSourceDecls, rnHsType, rnHsSigType ) where
+module RnSource (
+ rnSrcDecls, addTcgDUs,
+ rnTyClDecls, checkModDeprec,
+ rnBindGroups, rnBindGroupsAndThen, rnSplice
+ ) where
#include "HsVersions.h"
-import RnExpr
import HsSyn
-import HsPragmas
-import HsTypes ( hsTyVarNames, pprHsContext )
-import RdrName ( RdrName, isRdrDataCon, rdrNameOcc, isRdrTyVar, mkRdrNameWkr )
-import RdrHsSyn ( RdrNameContext, RdrNameHsType, RdrNameConDecl,
- extractRuleBndrsTyVars, extractHsTyRdrTyVars,
- extractHsTysRdrTyVars, extractHsCtxtRdrTyVars
- )
+import RdrName ( RdrName, isRdrDataCon, rdrNameOcc, elemLocalRdrEnv )
+import RdrHsSyn ( extractGenericPatTyVars )
import RnHsSyn
-import HsCore
-
-import RnBinds ( rnTopBinds, rnMethodBinds, renameSigs, unknownSigErr )
-import RnEnv ( bindTyVarsRn, lookupBndrRn, lookupOccRn, getIPName,
- lookupImplicitOccRn, lookupImplicitOccsRn,
- bindLocalsRn, bindLocalRn, bindLocalsFVRn, bindUVarRn,
- bindTyVarsFVRn, bindTyVarsFV2Rn, extendTyVarEnvFVRn,
- bindCoreLocalFVRn, bindCoreLocalsFVRn,
- checkDupOrQualNames, checkDupNames,
- mkImportedGlobalName, mkImportedGlobalFromRdrName,
- newDFunName, getDFunKey, newImplicitBinder,
- FreeVars, emptyFVs, plusFV, plusFVs, unitFV,
- addOneFV, mapFvRn
+import RnExpr ( rnLExpr, checkTH )
+import RnTypes ( rnLHsType, rnLHsTypes, rnHsSigType, rnHsTypeFVs, rnContext )
+import RnBinds ( rnTopBinds, rnBinds, rnMethodBinds,
+ rnBindsAndThen, renameSigs, checkSigs )
+import RnEnv ( lookupTopBndrRn, lookupTopFixSigNames,
+ lookupLocatedTopBndrRn, lookupLocatedOccRn,
+ lookupOccRn, newLocalsRn,
+ bindLocatedLocalsFV, bindPatSigTyVarsFV,
+ bindTyVarsRn, extendTyVarEnvFVRn,
+ bindLocalNames, newIPNameRn,
+ checkDupNames, mapFvRn,
+ unknownNameErr
)
-import RnMonad
+import TcRnMonad
-import FunDeps ( oclose )
+import BasicTypes ( TopLevelFlag(..) )
+import HscTypes ( FixityEnv, FixItem(..),
+ Deprecations, Deprecs(..), DeprecTxt, plusDeprecs )
import Class ( FunDep )
-
-import Name ( Name, OccName,
- ExportFlag(..), Provenance(..),
- nameOccName, NamedThing(..)
- )
+import Name ( Name, nameOccName )
import NameSet
-import OccName ( mkDefaultMethodOcc )
-import FiniteMap ( elemFM )
-import PrelInfo ( derivableClassKeys, cCallishClassKeys,
- deRefStablePtr_RDR, makeStablePtr_RDR,
- bindIO_RDR, returnIO_RDR
- )
-import Bag ( bagToList )
-import List ( partition, nub )
+import NameEnv
import Outputable
-import SrcLoc ( SrcLoc )
-import CmdLineOpts ( opt_GlasgowExts, opt_WarnUnusedMatches ) -- Warn of unused for-all'd tyvars
-import Unique ( Uniquable(..) )
-import ErrUtils ( Message )
-import CStrings ( isCLabelString )
-import Maybes ( maybeToBool, catMaybes )
-import Util
+import SrcLoc ( Located(..), unLoc, getLoc, noLoc )
+import CmdLineOpts ( DynFlag(..) )
+ -- Warn of unused for-all'd tyvars
+import Maybes ( seqMaybe )
+import Maybe ( catMaybes, isNothing )
\end{code}
-@rnDecl@ `renames' declarations.
+@rnSourceDecl@ `renames' declarations.
It simultaneously performs dependency analysis and precedence parsing.
It also does the following error checks:
\begin{enumerate}
\end{enumerate}
+\begin{code}
+rnSrcDecls :: HsGroup RdrName -> RnM (TcGblEnv, HsGroup Name)
+
+rnSrcDecls (HsGroup { hs_valds = [HsBindGroup binds sigs _],
+ hs_tyclds = tycl_decls,
+ hs_instds = inst_decls,
+ hs_fixds = fix_decls,
+ hs_depds = deprec_decls,
+ hs_fords = foreign_decls,
+ hs_defds = default_decls,
+ hs_ruleds = rule_decls })
+
+ = do { -- Deal with deprecations (returns only the extra deprecations)
+ deprecs <- rnSrcDeprecDecls deprec_decls ;
+ updGblEnv (\gbl -> gbl { tcg_deprecs = tcg_deprecs gbl `plusDeprecs` deprecs })
+ $ do {
+
+ -- Deal with top-level fixity decls
+ -- (returns the total new fixity env)
+ fix_env <- rnSrcFixityDecls fix_decls ;
+ updGblEnv (\gbl -> gbl { tcg_fix_env = fix_env })
+ $ do {
+
+ -- Rename other declarations
+ traceRn (text "Start rnmono") ;
+ (rn_val_decls, bind_dus) <- rnTopBinds binds sigs ;
+ traceRn (text "finish rnmono" <+> ppr rn_val_decls) ;
+
+ -- You might think that we could build proper def/use information
+ -- for type and class declarations, but they can be involved
+ -- in mutual recursion across modules, and we only do the SCC
+ -- analysis for them in the type checker.
+ -- So we content ourselves with gathering uses only; that
+ -- means we'll only report a declaration as unused if it isn't
+ -- mentioned at all. Ah well.
+ (rn_tycl_decls, src_fvs1)
+ <- mapFvRn (wrapLocFstM rnTyClDecl) tycl_decls ;
+ (rn_inst_decls, src_fvs2)
+ <- mapFvRn (wrapLocFstM rnSrcInstDecl) inst_decls ;
+ (rn_rule_decls, src_fvs3)
+ <- mapFvRn (wrapLocFstM rnHsRuleDecl) rule_decls ;
+ (rn_foreign_decls, src_fvs4)
+ <- mapFvRn (wrapLocFstM rnHsForeignDecl) foreign_decls ;
+ (rn_default_decls, src_fvs5)
+ <- mapFvRn (wrapLocFstM rnDefaultDecl) default_decls ;
+
+ let {
+ rn_group = HsGroup { hs_valds = rn_val_decls,
+ hs_tyclds = rn_tycl_decls,
+ hs_instds = rn_inst_decls,
+ hs_fixds = [],
+ hs_depds = [],
+ hs_fords = rn_foreign_decls,
+ hs_defds = rn_default_decls,
+ hs_ruleds = rn_rule_decls } ;
+
+ other_fvs = plusFVs [src_fvs1, src_fvs2, src_fvs3,
+ src_fvs4, src_fvs5] ;
+ src_dus = bind_dus `plusDU` usesOnly other_fvs
+ -- Note: src_dus will contain *uses* for locally-defined types
+ -- and classes, but no *defs* for them. (Because rnTyClDecl
+ -- returns only the uses.) This is a little
+ -- surprising but it doesn't actually matter at all.
+ } ;
+
+ traceRn (text "finish rnSrc" <+> ppr rn_group) ;
+ traceRn (text "finish Dus" <+> ppr src_dus ) ;
+ tcg_env <- getGblEnv ;
+ return (tcg_env `addTcgDUs` src_dus, rn_group)
+ }}}
+
+rnTyClDecls :: [LTyClDecl RdrName] -> RnM [LTyClDecl Name]
+rnTyClDecls tycl_decls = do
+ (decls', fvs) <- mapFvRn (wrapLocFstM rnTyClDecl) tycl_decls
+ return decls'
+
+addTcgDUs :: TcGblEnv -> DefUses -> TcGblEnv
+addTcgDUs tcg_env dus = tcg_env { tcg_dus = tcg_dus tcg_env `plusDU` dus }
+\end{code}
+
+
%*********************************************************
-%* *
-\subsection{Value declarations}
-%* *
+%* *
+ Source-code fixity declarations
+%* *
%*********************************************************
\begin{code}
-rnSourceDecls :: [RdrNameHsDecl] -> RnMS ([RenamedHsDecl], FreeVars)
- -- The decls get reversed, but that's ok
-
-rnSourceDecls decls
- = go emptyFVs [] decls
+rnSrcFixityDecls :: [LFixitySig RdrName] -> RnM FixityEnv
+rnSrcFixityDecls fix_decls
+ = getGblEnv `thenM` \ gbl_env ->
+ foldlM rnFixityDecl (tcg_fix_env gbl_env)
+ fix_decls `thenM` \ fix_env ->
+ traceRn (text "fixity env" <+> pprFixEnv fix_env) `thenM_`
+ returnM fix_env
+
+rnFixityDecl :: FixityEnv -> LFixitySig RdrName -> RnM FixityEnv
+rnFixityDecl fix_env (L loc (FixitySig rdr_name fixity))
+ = setSrcSpan loc $
+ -- GHC extension: look up both the tycon and data con
+ -- for con-like things
+ -- If neither are in scope, report an error; otherwise
+ -- add both to the fixity env
+ addLocM lookupTopFixSigNames rdr_name `thenM` \ names ->
+ if null names then
+ addLocErr rdr_name unknownNameErr `thenM_`
+ returnM fix_env
+ else
+ foldlM add fix_env names
where
- -- Fixity and deprecations have been dealt with already; ignore them
- go fvs ds' [] = returnRn (ds', fvs)
- go fvs ds' (FixD _:ds) = go fvs ds' ds
- go fvs ds' (DeprecD _:ds) = go fvs ds' ds
- go fvs ds' (d:ds) = rnDecl d `thenRn` \(d', fvs') ->
- go (fvs `plusFV` fvs') (d':ds') ds
+ add fix_env name
+ = case lookupNameEnv fix_env name of
+ Just (FixItem _ _ loc')
+ -> addLocErr rdr_name (dupFixityDecl loc') `thenM_`
+ returnM fix_env
+ Nothing -> returnM (extendNameEnv fix_env name fix_item)
+ where
+ fix_item = FixItem (nameOccName name) fixity (getLoc rdr_name)
+
+pprFixEnv :: FixityEnv -> SDoc
+pprFixEnv env
+ = pprWithCommas (\ (FixItem n f _) -> ppr f <+> ppr n)
+ (nameEnvElts env)
+
+dupFixityDecl loc rdr_name
+ = vcat [ptext SLIT("Multiple fixity declarations for") <+> quotes (ppr rdr_name),
+ ptext SLIT("also at ") <+> ppr loc
+ ]
\end{code}
%*********************************************************
-%* *
-\subsection{Value declarations}
-%* *
+%* *
+ Source-code deprecations declarations
+%* *
%*********************************************************
-\begin{code}
--- rnDecl does all the work
-rnDecl :: RdrNameHsDecl -> RnMS (RenamedHsDecl, FreeVars)
-
-rnDecl (ValD binds) = rnTopBinds binds `thenRn` \ (new_binds, fvs) ->
- returnRn (ValD new_binds, fvs)
+For deprecations, all we do is check that the names are in scope.
+It's only imported deprecations, dealt with in RnIfaces, that we
+gather them together.
+\begin{code}
+rnSrcDeprecDecls :: [LDeprecDecl RdrName] -> RnM Deprecations
+rnSrcDeprecDecls []
+ = returnM NoDeprecs
-rnDecl (SigD (IfaceSig name ty id_infos loc))
- = pushSrcLocRn loc $
- mkImportedGlobalFromRdrName name `thenRn` \ name' ->
- rnHsType doc_str ty `thenRn` \ (ty',fvs1) ->
- mapFvRn rnIdInfo id_infos `thenRn` \ (id_infos', fvs2) ->
- returnRn (SigD (IfaceSig name' ty' id_infos' loc), fvs1 `plusFV` fvs2)
- where
- doc_str = text "the interface signature for" <+> quotes (ppr name)
+rnSrcDeprecDecls decls
+ = mappM (addLocM rn_deprec) decls `thenM` \ pairs ->
+ returnM (DeprecSome (mkNameEnv (catMaybes pairs)))
+ where
+ rn_deprec (Deprecation rdr_name txt)
+ = lookupTopBndrRn rdr_name `thenM` \ name ->
+ returnM (Just (name, (rdrNameOcc rdr_name, txt)))
+
+checkModDeprec :: Maybe DeprecTxt -> Deprecations
+-- Check for a module deprecation; done once at top level
+checkModDeprec Nothing = NoDeprecs
+checkModDeprec (Just txt) = DeprecAll txt
\end{code}
%*********************************************************
%* *
-\subsection{Type declarations}
+\subsection{Source code 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.
-
\begin{code}
-rnDecl (TyClD (TyData new_or_data context tycon tyvars condecls nconstrs derivings pragmas src_loc))
- = pushSrcLocRn src_loc $
- lookupBndrRn tycon `thenRn` \ tycon' ->
- bindTyVarsFVRn data_doc tyvars $ \ tyvars' ->
- rnContext data_doc context `thenRn` \ (context', cxt_fvs) ->
- checkDupOrQualNames data_doc con_names `thenRn_`
- mapFvRn rnConDecl condecls `thenRn` \ (condecls', con_fvs) ->
- rnDerivs derivings `thenRn` \ (derivings', deriv_fvs) ->
- ASSERT(isNoDataPragmas pragmas)
- returnRn (TyClD (TyData new_or_data context' tycon' tyvars' condecls' nconstrs
- derivings' noDataPragmas src_loc),
- cxt_fvs `plusFV` con_fvs `plusFV` deriv_fvs)
+rnDefaultDecl (DefaultDecl tys)
+ = mapFvRn (rnHsTypeFVs doc_str) tys `thenM` \ (tys', fvs) ->
+ returnM (DefaultDecl tys', fvs)
where
- data_doc = text "the data type declaration for" <+> quotes (ppr tycon)
- con_names = map conDeclName condecls
-
-rnDecl (TyClD (TySynonym name tyvars ty src_loc))
- = pushSrcLocRn src_loc $
- lookupBndrRn name `thenRn` \ name' ->
- bindTyVarsFVRn syn_doc tyvars $ \ tyvars' ->
- rnHsType syn_doc (unquantify ty) `thenRn` \ (ty', ty_fvs) ->
- returnRn (TyClD (TySynonym name' tyvars' ty' src_loc), ty_fvs)
- where
- syn_doc = text "the declaration for type synonym" <+> quotes (ppr name)
-
- -- For H98 we do *not* universally quantify on the RHS of a synonym
- -- Silently discard context... but the tyvars in the rest won't be in scope
- unquantify (HsForAllTy Nothing ctxt ty) | not opt_GlasgowExts = ty
- unquantify ty = ty
-
-rnDecl (TyClD (ClassDecl context cname tyvars fds sigs mbinds pragmas
- tname dname dwname snames src_loc))
- = pushSrcLocRn src_loc $
-
- lookupBndrRn cname `thenRn` \ cname' ->
-
- -- Deal with the implicit tycon and datacon name
- -- They aren't in scope (because they aren't visible to the user)
- -- and what we want to do is simply look them up in the cache;
- -- we jolly well ought to get a 'hit' there!
- -- So the 'Imported' part of this call is not relevant.
- -- Unclean; but since these two are the only place this happens
- -- I can't work up the energy to do it more beautifully
- mkImportedGlobalFromRdrName tname `thenRn` \ tname' ->
- mkImportedGlobalFromRdrName dname `thenRn` \ dname' ->
- mkImportedGlobalFromRdrName dwname `thenRn` \ dwname' ->
- mapRn mkImportedGlobalFromRdrName snames `thenRn` \ snames' ->
-
- -- Tyvars scope over bindings and context
- bindTyVarsFV2Rn cls_doc tyvars ( \ clas_tyvar_names tyvars' ->
-
- -- Check the superclasses
- rnContext cls_doc context `thenRn` \ (context', cxt_fvs) ->
-
- -- Check the functional dependencies
- rnFds cls_doc fds `thenRn` \ (fds', fds_fvs) ->
-
- -- Check the signatures
- let
- -- First process the class op sigs, then the fixity sigs.
- (op_sigs, non_op_sigs) = partition isClassOpSig sigs
- in
- checkDupOrQualNames sig_doc sig_rdr_names_w_locs `thenRn_`
- mapFvRn (rn_op cname' clas_tyvar_names fds') op_sigs `thenRn` \ (sigs', sig_fvs) ->
- let
- binders = mkNameSet [ nm | (ClassOpSig nm _ _ _ _) <- sigs' ]
- in
- renameSigs (okClsDclSig binders) non_op_sigs `thenRn` \ (non_ops', fix_fvs) ->
-
- -- Check the methods
- checkDupOrQualNames meth_doc meth_rdr_names_w_locs `thenRn_`
- rnMethodBinds mbinds
- `thenRn` \ (mbinds', meth_fvs) ->
-
- -- Typechecker is responsible for checking that we only
- -- give default-method bindings for things in this class.
- -- The renamer *could* check this for class decls, but can't
- -- for instance decls.
-
- ASSERT(isNoClassPragmas pragmas)
- returnRn (TyClD (ClassDecl context' cname' tyvars' fds' (non_ops' ++ sigs') mbinds'
- NoClassPragmas tname' dname' dwname' snames' src_loc),
- sig_fvs `plusFV`
- fix_fvs `plusFV`
- cxt_fvs `plusFV`
- fds_fvs `plusFV`
- meth_fvs
- )
- )
- where
- cls_doc = text "the declaration for class" <+> ppr cname
- sig_doc = text "the signatures for class" <+> ppr cname
- meth_doc = text "the default-methods for class" <+> ppr cname
-
- sig_rdr_names_w_locs = [(op,locn) | ClassOpSig op _ _ _ locn <- sigs]
- meth_rdr_names_w_locs = bagToList (collectMonoBinders mbinds)
- meth_rdr_names = map fst meth_rdr_names_w_locs
-
- rn_op clas clas_tyvars clas_fds sig@(ClassOpSig op dm_rdr_name explicit_dm ty locn)
- = pushSrcLocRn locn $
- lookupBndrRn op `thenRn` \ op_name ->
-
- -- Check the signature
- rnHsSigType (quotes (ppr op)) ty `thenRn` \ (new_ty, op_ty_fvs) ->
- let
- check_in_op_ty clas_tyvar =
- checkRn (clas_tyvar `elemNameSet` oclose clas_fds op_ty_fvs)
- (classTyVarNotInOpTyErr clas_tyvar sig)
- in
- mapRn_ check_in_op_ty clas_tyvars `thenRn_`
-
- -- Make the default-method name
- getModeRn `thenRn` \ mode ->
- (case mode of
- SourceMode -> -- Source class decl
- newImplicitBinder (mkDefaultMethodOcc (rdrNameOcc op)) locn `thenRn` \ dm_name ->
- returnRn (dm_name, op `elem` meth_rdr_names, emptyFVs)
-
- InterfaceMode
- -> -- Imported class that has a default method decl
- -- See comments with tname, snames, above
- lookupImplicitOccRn dm_rdr_name `thenRn` \ dm_name ->
- returnRn (dm_name, explicit_dm, if explicit_dm then unitFV dm_name else emptyFVs)
- -- An imported class decl for a class decl that had an explicit default
- -- method, mentions, rather than defines,
- -- the default method, so we must arrange to pull it in
- ) `thenRn` \ (dm_name, final_explicit_dm, dm_fvs) ->
-
- returnRn (ClassOpSig op_name dm_name final_explicit_dm new_ty locn, op_ty_fvs `plusFV` dm_fvs)
+ doc_str = text "In a `default' declaration"
\end{code}
-
%*********************************************************
%* *
-\subsection{Instance declarations}
+ Bindings
%* *
%*********************************************************
-\begin{code}
-rnDecl (InstD (InstDecl inst_ty mbinds uprags dfun_rdr_name src_loc))
- = pushSrcLocRn src_loc $
- rnHsSigType (text "an instance decl") inst_ty `thenRn` \ (inst_ty', inst_fvs) ->
- let
- inst_tyvars = case inst_ty' of
- HsForAllTy (Just inst_tyvars) _ _ -> inst_tyvars
- other -> []
- -- (Slightly strangely) the forall-d tyvars scope over
- -- the method bindings too
- in
+These chaps are here, rather than in TcBinds, so that there
+is just one hi-boot file (for RnSource). rnSrcDecls is part
+of the loop too, and it must be defined in this module.
- -- Rename the bindings
- -- NB meth_names can be qualified!
- checkDupNames meth_doc meth_names `thenRn_`
- extendTyVarEnvFVRn inst_tyvars (
- rnMethodBinds mbinds
- ) `thenRn` \ (mbinds', meth_fvs) ->
- let
- binders = mkNameSet (map fst (bagToList (collectMonoBinders mbinds')))
- in
- -- Rename the prags and signatures.
- -- Note that the type variables are not in scope here,
- -- so that instance Eq a => Eq (T a) where
- -- {-# SPECIALISE instance Eq a => Eq (T [a]) #-}
- -- works OK.
- renameSigs (okInstDclSig binders) uprags `thenRn` \ (new_uprags, prag_fvs) ->
-
- getModeRn `thenRn` \ mode ->
- (case mode of
- InterfaceMode -> lookupImplicitOccRn dfun_rdr_name `thenRn` \ dfun_name ->
- returnRn (dfun_name, unitFV dfun_name)
- SourceMode -> newDFunName (getDFunKey inst_ty') src_loc
- `thenRn` \ dfun_name ->
- returnRn (dfun_name, emptyFVs)
- )
- `thenRn` \ (dfun_name, dfun_fv) ->
-
- -- The typechecker checks that all the bindings are for the right class.
- returnRn (InstD (InstDecl inst_ty' mbinds' new_uprags dfun_name src_loc),
- inst_fvs `plusFV` meth_fvs `plusFV` prag_fvs `plusFV` dfun_fv)
- where
- meth_doc = text "the bindings in an instance declaration"
- meth_names = bagToList (collectMonoBinders mbinds)
+\begin{code}
+rnBindGroups :: [HsBindGroup RdrName] -> RnM ([HsBindGroup Name], DefUses)
+-- This version assumes that the binders are already in scope
+-- It's used only in 'mdo'
+rnBindGroups []
+ = returnM ([], emptyDUs)
+rnBindGroups [HsBindGroup bind sigs _]
+ = rnBinds NotTopLevel bind sigs
+rnBindGroups b@[HsIPBinds bind]
+ = do addErr (badIpBinds b)
+ returnM ([], emptyDUs)
+rnBindGroups _
+ = panic "rnBindGroups"
+
+rnBindGroupsAndThen
+ :: [HsBindGroup RdrName]
+ -> ([HsBindGroup Name] -> RnM (result, FreeVars))
+ -> RnM (result, FreeVars)
+-- This version (a) assumes that the binding vars are not already in scope
+-- (b) removes the binders from the free vars of the thing inside
+-- The parser doesn't produce ThenBinds
+rnBindGroupsAndThen [] thing_inside
+ = thing_inside []
+rnBindGroupsAndThen [HsBindGroup bind sigs _] thing_inside
+ = rnBindsAndThen bind sigs $ \ groups -> thing_inside groups
+rnBindGroupsAndThen [HsIPBinds binds] thing_inside
+ = rnIPBinds binds `thenM` \ (binds',fv_binds) ->
+ thing_inside [HsIPBinds binds'] `thenM` \ (thing, fvs_thing) ->
+ returnM (thing, fvs_thing `plusFV` fv_binds)
+
+rnIPBinds [] = returnM ([], emptyFVs)
+rnIPBinds (bind : binds)
+ = wrapLocFstM rnIPBind bind `thenM` \ (bind', fvBind) ->
+ rnIPBinds binds `thenM` \ (binds',fvBinds) ->
+ returnM (bind' : binds', fvBind `plusFV` fvBinds)
+
+rnIPBind (IPBind n expr)
+ = newIPNameRn n `thenM` \ name ->
+ rnLExpr expr `thenM` \ (expr',fvExpr) ->
+ return (IPBind name expr', fvExpr)
+
+badIpBinds binds
+ = hang (ptext SLIT("Implicit-parameter bindings illegal in 'mdo':")) 4
+ (ppr binds)
\end{code}
+
%*********************************************************
%* *
-\subsection{Default declarations}
+\subsection{Foreign declarations}
%* *
%*********************************************************
\begin{code}
-rnDecl (DefD (DefaultDecl tys src_loc))
- = pushSrcLocRn src_loc $
- rnHsTypes doc_str tys `thenRn` \ (tys', fvs) ->
- returnRn (DefD (DefaultDecl tys' src_loc), fvs)
- where
- doc_str = text "a `default' declaration"
+rnHsForeignDecl (ForeignImport name ty spec isDeprec)
+ = lookupLocatedTopBndrRn name `thenM` \ name' ->
+ rnHsTypeFVs (fo_decl_msg name) ty `thenM` \ (ty', fvs) ->
+ returnM (ForeignImport name' ty' spec isDeprec, fvs)
+
+rnHsForeignDecl (ForeignExport name ty spec isDeprec)
+ = lookupLocatedOccRn name `thenM` \ name' ->
+ rnHsTypeFVs (fo_decl_msg name) ty `thenM` \ (ty', fvs) ->
+ returnM (ForeignExport name' ty' spec isDeprec, fvs )
+ -- NB: a foreign export is an *occurrence site* for name, so
+ -- we add it to the free-variable list. It might, for example,
+ -- be imported from another module
+
+fo_decl_msg name = ptext SLIT("In the foreign declaration for") <+> ppr name
\end{code}
+
%*********************************************************
%* *
-\subsection{Foreign declarations}
+\subsection{Instance declarations}
%* *
%*********************************************************
\begin{code}
-rnDecl (ForD (ForeignDecl name imp_exp ty ext_nm cconv src_loc))
- = pushSrcLocRn src_loc $
- lookupOccRn name `thenRn` \ name' ->
+rnSrcInstDecl (InstDecl inst_ty mbinds uprags)
+ -- Used for both source and interface file decls
+ = rnHsSigType (text "an instance decl") inst_ty `thenM` \ inst_ty' ->
+
+ -- Rename the bindings
+ -- The typechecker (not the renamer) checks that all
+ -- the bindings are for the right class
+ let
+ meth_doc = text "In the bindings in an instance declaration"
+ meth_names = collectHsBindLocatedBinders mbinds
+ (inst_tyvars, _, cls,_) = splitHsInstDeclTy (unLoc inst_ty')
+ in
+ checkDupNames meth_doc meth_names `thenM_`
+ extendTyVarEnvForMethodBinds inst_tyvars (
+ -- (Slightly strangely) the forall-d tyvars scope over
+ -- the method bindings too
+ rnMethodBinds cls [] mbinds
+ ) `thenM` \ (mbinds', meth_fvs) ->
+ -- Rename the prags and signatures.
+ -- Note that the type variables are not in scope here,
+ -- so that instance Eq a => Eq (T a) where
+ -- {-# SPECIALISE instance Eq a => Eq (T [a]) #-}
+ -- works OK.
+ --
+ -- But the (unqualified) method names are in scope
let
- extra_fvs FoExport
- | isDyn =
- lookupImplicitOccsRn [makeStablePtr_RDR, deRefStablePtr_RDR,
- bindIO_RDR, returnIO_RDR]
- | otherwise =
- lookupImplicitOccsRn [bindIO_RDR, returnIO_RDR] `thenRn` \ fvs ->
- returnRn (addOneFV fvs name')
- extra_fvs other = returnRn emptyFVs
+ binders = collectHsBindBinders mbinds'
in
- checkRn (ok_ext_nm ext_nm) (badExtName ext_nm) `thenRn_`
+ bindLocalNames binders (renameSigs uprags) `thenM` \ uprags' ->
+ checkSigs (okInstDclSig (mkNameSet binders)) uprags' `thenM_`
- extra_fvs imp_exp `thenRn` \ fvs1 ->
+ returnM (InstDecl inst_ty' mbinds' uprags',
+ meth_fvs `plusFV` hsSigsFVs uprags'
+ `plusFV` extractHsTyNames inst_ty')
+\end{code}
- rnHsSigType fo_decl_msg ty `thenRn` \ (ty', fvs2) ->
- returnRn (ForD (ForeignDecl name' imp_exp ty' ext_nm cconv src_loc),
- fvs1 `plusFV` fvs2)
- where
- fo_decl_msg = ptext SLIT("a foreign declaration")
- isDyn = isDynamicExtName ext_nm
+For the method bindings in class and instance decls, we extend the
+type variable environment iff -fglasgow-exts
- ok_ext_nm Dynamic = True
- ok_ext_nm (ExtName nm (Just mb)) = isCLabelString nm && isCLabelString mb
- ok_ext_nm (ExtName nm Nothing) = isCLabelString nm
+\begin{code}
+extendTyVarEnvForMethodBinds tyvars thing_inside
+ = doptM Opt_GlasgowExts `thenM` \ opt_GlasgowExts ->
+ if opt_GlasgowExts then
+ extendTyVarEnvFVRn (map hsLTyVarName tyvars) thing_inside
+ else
+ thing_inside
\end{code}
+
%*********************************************************
%* *
\subsection{Rules}
%*********************************************************
\begin{code}
-rnDecl (RuleD (IfaceRule rule_name vars fn args rhs src_loc))
- = pushSrcLocRn src_loc $
- lookupOccRn fn `thenRn` \ fn' ->
- rnCoreBndrs vars $ \ vars' ->
- mapFvRn rnCoreExpr args `thenRn` \ (args', fvs1) ->
- rnCoreExpr rhs `thenRn` \ (rhs', fvs2) ->
- returnRn (RuleD (IfaceRule rule_name vars' fn' args' rhs' src_loc),
- (fvs1 `plusFV` fvs2) `addOneFV` fn')
-
-rnDecl (RuleD (IfaceRuleOut fn rule))
- -- This one is used for BuiltInRules
- -- The rule itself is already done, but the thing
- -- to attach it to is not.
- = lookupOccRn fn `thenRn` \ fn' ->
- returnRn (RuleD (IfaceRuleOut fn' rule), unitFV fn')
-
-rnDecl (RuleD (HsRule rule_name tvs vars lhs rhs src_loc))
- = ASSERT( null tvs )
- pushSrcLocRn src_loc $
-
- bindTyVarsFV2Rn doc (map UserTyVar sig_tvs) $ \ sig_tvs' _ ->
- bindLocalsFVRn doc (map get_var vars) $ \ ids ->
- mapFvRn rn_var (vars `zip` ids) `thenRn` \ (vars', fv_vars) ->
-
- rnExpr lhs `thenRn` \ (lhs', fv_lhs) ->
- rnExpr rhs `thenRn` \ (rhs', fv_rhs) ->
- checkRn (validRuleLhs ids lhs')
- (badRuleLhsErr rule_name lhs') `thenRn_`
+rnHsRuleDecl (HsRule rule_name act vars lhs rhs)
+ = bindPatSigTyVarsFV (collectRuleBndrSigTys vars) $
+
+ bindLocatedLocalsFV doc (map get_var vars) $ \ ids ->
+ mapFvRn rn_var (vars `zip` ids) `thenM` \ (vars', fv_vars) ->
+
+ rnLExpr lhs `thenM` \ (lhs', fv_lhs) ->
+ rnLExpr rhs `thenM` \ (rhs', fv_rhs) ->
+ let
+ mb_bad = validRuleLhs ids lhs'
+ in
+ checkErr (isNothing mb_bad)
+ (badRuleLhsErr rule_name lhs' mb_bad) `thenM_`
let
bad_vars = [var | var <- ids, not (var `elemNameSet` fv_lhs)]
in
- mapRn (addErrRn . badRuleVar rule_name) bad_vars `thenRn_`
- returnRn (RuleD (HsRule rule_name sig_tvs' vars' lhs' rhs' src_loc),
- fv_vars `plusFV` fv_lhs `plusFV` fv_rhs)
+ mappM (addErr . badRuleVar rule_name) bad_vars `thenM_`
+ returnM (HsRule rule_name act vars' lhs' rhs',
+ fv_vars `plusFV` fv_lhs `plusFV` fv_rhs)
where
- doc = text "the transformation rule" <+> ptext rule_name
- sig_tvs = extractRuleBndrsTyVars vars
+ doc = text "In the transformation rule" <+> ftext rule_name
get_var (RuleBndr v) = v
get_var (RuleBndrSig v _) = v
- rn_var (RuleBndr v, id) = returnRn (RuleBndr id, emptyFVs)
- rn_var (RuleBndrSig v t, id) = rnHsType doc t `thenRn` \ (t', fvs) ->
- returnRn (RuleBndrSig id t', fvs)
+ rn_var (RuleBndr (L loc v), id)
+ = returnM (RuleBndr (L loc id), emptyFVs)
+ rn_var (RuleBndrSig (L loc v) t, id)
+ = rnHsTypeFVs doc t `thenM` \ (t', fvs) ->
+ returnM (RuleBndrSig (L loc id) t', fvs)
\end{code}
+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 also restrict the form of the LHS so
+that it may be plausibly matched. Basically you only get to write ordinary
+applications. (E.g. a case expression is not allowed: too elaborate.)
-%*********************************************************
-%* *
-\subsection{Support code for type/data declarations}
-%* *
-%*********************************************************
-
-\begin{code}
-rnDerivs :: Maybe [RdrName] -> RnMS (Maybe [Name], FreeVars)
-
-rnDerivs Nothing -- derivs not specified
- = returnRn (Nothing, emptyFVs)
-
-rnDerivs (Just clss)
- = mapRn do_one clss `thenRn` \ clss' ->
- returnRn (Just clss', mkNameSet clss')
- where
- do_one cls = lookupOccRn cls `thenRn` \ clas_name ->
- checkRn (getUnique clas_name `elem` derivableClassKeys)
- (derivingNonStdClassErr clas_name) `thenRn_`
- returnRn clas_name
-\end{code}
+NB: if you add new cases here, make sure you add new ones to TcRule.ruleLhsTvs
\begin{code}
-conDeclName :: RdrNameConDecl -> (RdrName, SrcLoc)
-conDeclName (ConDecl n _ _ _ _ l) = (n,l)
-
-rnConDecl :: RdrNameConDecl -> RnMS (RenamedConDecl, FreeVars)
-rnConDecl (ConDecl name wkr tvs cxt details locn)
- = pushSrcLocRn locn $
- checkConName name `thenRn_`
- lookupBndrRn name `thenRn` \ new_name ->
-
- mkImportedGlobalFromRdrName wkr `thenRn` \ new_wkr ->
- -- See comments with ClassDecl
-
- bindTyVarsFVRn doc tvs $ \ new_tyvars ->
- rnContext doc cxt `thenRn` \ (new_context, cxt_fvs) ->
- rnConDetails doc locn details `thenRn` \ (new_details, det_fvs) ->
- returnRn (ConDecl new_name new_wkr new_tyvars new_context new_details locn,
- cxt_fvs `plusFV` det_fvs)
+validRuleLhs :: [Name] -> LHsExpr Name -> Maybe (HsExpr Name)
+-- Nothing => OK
+-- Just e => Not ok, and e is the offending expression
+validRuleLhs foralls lhs
+ = checkl lhs
where
- doc = text "the definition of data constructor" <+> quotes (ppr name)
-
-rnConDetails doc locn (VanillaCon tys)
- = mapFvRn (rnBangTy doc) tys `thenRn` \ (new_tys, fvs) ->
- returnRn (VanillaCon new_tys, fvs)
+ checkl (L loc e) = check e
-rnConDetails doc locn (InfixCon ty1 ty2)
- = rnBangTy doc ty1 `thenRn` \ (new_ty1, fvs1) ->
- rnBangTy doc ty2 `thenRn` \ (new_ty2, fvs2) ->
- returnRn (InfixCon new_ty1 new_ty2, fvs1 `plusFV` fvs2)
+ check (OpApp e1 op _ e2) = checkl op `seqMaybe` checkl_e e1 `seqMaybe` checkl_e e2
+ check (HsApp e1 e2) = checkl e1 `seqMaybe` checkl_e e2
+ check (HsVar v) | v `notElem` foralls = Nothing
+ check other = Just other -- Failure
-rnConDetails doc locn (NewCon ty mb_field)
- = rnHsType doc ty `thenRn` \ (new_ty, fvs) ->
- rn_field mb_field `thenRn` \ new_mb_field ->
- returnRn (NewCon new_ty new_mb_field, fvs)
- where
- rn_field Nothing = returnRn Nothing
- rn_field (Just f) =
- lookupBndrRn f `thenRn` \ new_f ->
- returnRn (Just new_f)
-
-rnConDetails doc locn (RecCon fields)
- = checkDupOrQualNames doc field_names `thenRn_`
- mapFvRn (rnField doc) fields `thenRn` \ (new_fields, fvs) ->
- returnRn (RecCon new_fields, fvs)
- where
- field_names = [(fld, locn) | (flds, _) <- fields, fld <- flds]
+ checkl_e (L loc e) = check_e e
-rnField doc (names, ty)
- = mapRn lookupBndrRn names `thenRn` \ new_names ->
- rnBangTy doc ty `thenRn` \ (new_ty, fvs) ->
- returnRn ((new_names, new_ty), fvs)
+ check_e (HsVar v) = Nothing
+ check_e (HsPar e) = checkl_e e
+ check_e (HsLit e) = Nothing
+ check_e (HsOverLit e) = Nothing
-rnBangTy doc (Banged ty)
- = rnHsType doc ty `thenRn` \ (new_ty, fvs) ->
- returnRn (Banged new_ty, fvs)
+ check_e (OpApp e1 op _ e2) = checkl_e e1 `seqMaybe` checkl_e op `seqMaybe` checkl_e e2
+ check_e (HsApp e1 e2) = checkl_e e1 `seqMaybe` checkl_e e2
+ check_e (NegApp e _) = checkl_e e
+ check_e (ExplicitList _ es) = checkl_es es
+ check_e (ExplicitTuple es _) = checkl_es es
+ check_e other = Just other -- Fails
-rnBangTy doc (Unbanged ty)
- = rnHsType doc ty `thenRn` \ (new_ty, fvs) ->
- returnRn (Unbanged new_ty, fvs)
+ checkl_es es = foldr (seqMaybe . checkl_e) Nothing es
-rnBangTy doc (Unpacked ty)
- = rnHsType doc ty `thenRn` \ (new_ty, fvs) ->
- returnRn (Unpacked new_ty, fvs)
-
--- This data decl will parse OK
--- data T = a Int
--- treating "a" as the constructor.
--- It is really hard to make the parser spot this malformation.
--- So the renamer has to check that the constructor is legal
---
--- We can get an operator as the constructor, even in the prefix form:
--- data T = :% Int Int
--- from interface files, which always print in prefix form
+badRuleLhsErr name lhs (Just 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")
-checkConName name
- = checkRn (isRdrDataCon name)
- (badDataCon name)
+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}
%*********************************************************
%* *
-\subsection{Support code to rename types}
+\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.
+
\begin{code}
-rnHsSigType :: SDoc -> RdrNameHsType -> RnMS (RenamedHsType, FreeVars)
- -- rnHsSigType is used for source-language type signatures,
- -- which use *implicit* universal quantification.
-rnHsSigType doc_str ty
- = rnHsType (text "the type signature for" <+> doc_str) ty
-
----------------------------------------
-rnHsType :: SDoc -> RdrNameHsType -> RnMS (RenamedHsType, FreeVars)
-
-rnHsType doc (HsForAllTy Nothing ctxt ty)
- -- Implicit quantifiction in source code (no kinds on tyvars)
- -- Given the signature C => T we universally quantify
- -- over FV(T) \ {in-scope-tyvars}
- = getLocalNameEnv `thenRn` \ name_env ->
- let
- mentioned_in_tau = extractHsTyRdrTyVars ty
- mentioned_in_ctxt = extractHsCtxtRdrTyVars ctxt
- mentioned = nub (mentioned_in_tau ++ mentioned_in_ctxt)
- forall_tyvars = filter (not . (`elemFM` name_env)) mentioned
- in
- rnForAll doc (map UserTyVar forall_tyvars) ctxt ty
-
-rnHsType doc (HsForAllTy (Just forall_tyvars) ctxt tau)
- -- Explicit quantification.
- -- Check that the forall'd tyvars are actually
- -- mentioned in the type, and produce a warning if not
- = let
- mentioned_in_tau = extractHsTyRdrTyVars tau
- mentioned_in_ctxt = extractHsCtxtRdrTyVars ctxt
- mentioned = nub (mentioned_in_tau ++ mentioned_in_ctxt)
- forall_tyvar_names = hsTyVarNames forall_tyvars
-
- -- Explicitly quantified but not mentioned in ctxt or tau
- warn_guys = filter (`notElem` mentioned) forall_tyvar_names
- in
- mapRn_ (forAllWarn doc tau) warn_guys `thenRn_`
- rnForAll doc forall_tyvars ctxt tau
-
-rnHsType doc (HsTyVar tyvar)
- = lookupOccRn tyvar `thenRn` \ tyvar' ->
- returnRn (HsTyVar tyvar', unitFV tyvar')
-
-rnHsType doc (HsFunTy ty1 ty2)
- = rnHsType doc ty1 `thenRn` \ (ty1', fvs1) ->
- -- Might find a for-all as the arg of a function type
- rnHsType doc ty2 `thenRn` \ (ty2', fvs2) ->
- -- Or as the result. This happens when reading Prelude.hi
- -- when we find return :: forall m. Monad m -> forall a. a -> m a
- returnRn (HsFunTy ty1' ty2', fvs1 `plusFV` fvs2)
-
-rnHsType doc (HsListTy ty)
- = rnHsType doc ty `thenRn` \ (ty', fvs) ->
- returnRn (HsListTy ty', fvs `addOneFV` listTyCon_name)
-
--- Unboxed tuples are allowed to have poly-typed arguments. These
--- sometimes crop up as a result of CPR worker-wrappering dictionaries.
-rnHsType doc (HsTupleTy (HsTupCon _ boxity) tys)
- -- Don't do lookupOccRn, because this is built-in syntax
- -- so it doesn't need to be in scope
- = mapFvRn (rnHsType doc) tys `thenRn` \ (tys', fvs) ->
- returnRn (HsTupleTy (HsTupCon n' boxity) tys', fvs `addOneFV` n')
- where
- n' = tupleTyCon_name boxity (length tys)
-
+rnTyClDecl (ForeignType {tcdLName = name, tcdFoType = fo_type, tcdExtName = ext_name})
+ = lookupLocatedTopBndrRn name `thenM` \ name' ->
+ returnM (ForeignType {tcdLName = name', tcdFoType = fo_type, tcdExtName = ext_name},
+ emptyFVs)
+
+rnTyClDecl (TyData {tcdND = new_or_data, tcdCtxt = context, tcdLName = tycon,
+ tcdTyVars = tyvars, tcdCons = condecls,
+ tcdKindSig = sig, tcdDerivs = derivs})
+ | is_vanilla -- Normal Haskell data type decl
+ = ASSERT( isNothing sig ) -- In normal H98 form, kind signature on the
+ -- data type is syntactically illegal
+ bindTyVarsRn data_doc tyvars $ \ tyvars' ->
+ do { tycon' <- lookupLocatedTopBndrRn tycon
+ ; context' <- rnContext data_doc context
+ ; (derivs', deriv_fvs) <- rn_derivs derivs
+ ; checkDupNames data_doc con_names
+ ; condecls' <- rnConDecls (unLoc tycon') condecls
+ ; returnM (TyData {tcdND = new_or_data, tcdCtxt = context', tcdLName = tycon',
+ tcdTyVars = tyvars', tcdKindSig = Nothing, tcdCons = condecls',
+ tcdDerivs = derivs'},
+ delFVs (map hsLTyVarName tyvars') $
+ extractHsCtxtTyNames context' `plusFV`
+ plusFVs (map conDeclFVs condecls') `plusFV`
+ deriv_fvs) }
+
+ | otherwise -- GADT
+ = ASSERT( null (unLoc context) )
+ do { tycon' <- lookupLocatedTopBndrRn tycon
+ ; tyvars' <- bindTyVarsRn data_doc tyvars
+ (\ tyvars' -> return tyvars')
+ -- For GADTs, the type variables in the declaration
+ -- do not scope over the constructor signatures
+ -- data T a where { T1 :: forall b. b-> b }
+ ; (derivs', deriv_fvs) <- rn_derivs derivs
+ ; checkDupNames data_doc con_names
+ ; condecls' <- rnConDecls (unLoc tycon') condecls
+ ; returnM (TyData {tcdND = new_or_data, tcdCtxt = noLoc [], tcdLName = tycon',
+ tcdTyVars = tyvars', tcdCons = condecls', tcdKindSig = sig,
+ tcdDerivs = derivs'},
+ plusFVs (map conDeclFVs condecls') `plusFV` deriv_fvs) }
-rnHsType doc (HsAppTy ty1 ty2)
- = rnHsType doc ty1 `thenRn` \ (ty1', fvs1) ->
- rnHsType doc ty2 `thenRn` \ (ty2', fvs2) ->
- returnRn (HsAppTy ty1' ty2', fvs1 `plusFV` fvs2)
-
-rnHsType doc (HsPredTy pred)
- = rnPred doc pred `thenRn` \ (pred', fvs) ->
- returnRn (HsPredTy pred', fvs)
-
-rnHsType doc (HsUsgForAllTy uv_rdr ty)
- = bindUVarRn doc uv_rdr $ \ uv_name ->
- rnHsType doc ty `thenRn` \ (ty', fvs) ->
- returnRn (HsUsgForAllTy uv_name ty',
- fvs )
-
-rnHsType doc (HsUsgTy usg ty)
- = newUsg usg `thenRn` \ (usg', usg_fvs) ->
- rnHsType doc ty `thenRn` \ (ty', ty_fvs) ->
- -- A for-all can occur inside a usage annotation
- returnRn (HsUsgTy usg' ty',
- usg_fvs `plusFV` ty_fvs)
where
- newUsg usg = case usg of
- HsUsOnce -> returnRn (HsUsOnce, emptyFVs)
- HsUsMany -> returnRn (HsUsMany, emptyFVs)
- HsUsVar uv_rdr -> lookupOccRn uv_rdr `thenRn` \ uv_name ->
- returnRn (HsUsVar uv_name, emptyFVs)
+ is_vanilla = case condecls of -- Yuk
+ [] -> True
+ L _ (ConDecl {}) : _ -> True
+ other -> False
-rnHsTypes doc tys = mapFvRn (rnHsType doc) tys
-\end{code}
+ data_doc = text "In the data type declaration for" <+> quotes (ppr tycon)
+ con_names = map con_names_helper condecls
-\begin{code}
--- We use lookupOcc here because this is interface file only stuff
--- and we need the workers...
-rnHsTupCon (HsTupCon n boxity)
- = lookupOccRn n `thenRn` \ n' ->
- returnRn (HsTupCon n' boxity, unitFV n')
-
-rnHsTupConWkr (HsTupCon n boxity)
- -- Tuple construtors are for the *worker* of the tuple
- -- Going direct saves needless messing about
- = lookupOccRn (mkRdrNameWkr n) `thenRn` \ n' ->
- returnRn (HsTupCon n' boxity, unitFV n')
-\end{code}
+ con_names_helper (L _ (ConDecl n _ _ _)) = n
+ con_names_helper (L _ (GadtDecl n _)) = n
-\begin{code}
--- Check that each constraint mentions at least one of the forall'd type variables
--- Since the forall'd type variables are a subset of the free tyvars
--- of the tau-type part, this guarantees that every constraint mentions
--- at least one of the free tyvars in ty
-checkConstraints doc forall_tyvars tau_vars ctxt ty
- = mapRn (checkPred doc forall_tyvars ty) ctxt `thenRn` \ maybe_ctxt' ->
- returnRn (catMaybes maybe_ctxt')
- -- Remove problem ones, to avoid duplicate error message.
-
-checkPred doc forall_tyvars ty p@(HsPClass clas tys)
- | not_univ = failWithRn Nothing (univErr doc p ty)
- | otherwise = returnRn (Just p)
+ rn_derivs Nothing = returnM (Nothing, emptyFVs)
+ rn_derivs (Just ds) = rnLHsTypes data_doc ds `thenM` \ ds' ->
+ returnM (Just ds', extractHsTyNames_s ds')
+
+rnTyClDecl (TySynonym {tcdLName = name, tcdTyVars = tyvars, tcdSynRhs = ty})
+ = lookupLocatedTopBndrRn name `thenM` \ name' ->
+ bindTyVarsRn syn_doc tyvars $ \ tyvars' ->
+ rnHsTypeFVs syn_doc ty `thenM` \ (ty', fvs) ->
+ returnM (TySynonym {tcdLName = name', tcdTyVars = tyvars',
+ tcdSynRhs = ty'},
+ delFVs (map hsLTyVarName tyvars') fvs)
where
- ct_vars = extractHsTysRdrTyVars tys
- not_univ = -- At least one of the tyvars in each constraint must
- -- be universally quantified. This restriction isn't in Hugs
- not (any (`elem` forall_tyvars) ct_vars)
-checkPred doc forall_tyvars ty p@(HsPIParam _ _)
- = returnRn (Just p)
-
-rnForAll doc forall_tyvars ctxt ty
- = bindTyVarsFVRn doc forall_tyvars $ \ new_tyvars ->
- rnContext doc ctxt `thenRn` \ (new_ctxt, cxt_fvs) ->
- rnHsType doc ty `thenRn` \ (new_ty, ty_fvs) ->
- returnRn (mkHsForAllTy (Just new_tyvars) new_ctxt new_ty,
- cxt_fvs `plusFV` ty_fvs)
-\end{code}
+ syn_doc = text "In the declaration for type synonym" <+> quotes (ppr name)
-\begin{code}
-rnContext :: SDoc -> RdrNameContext -> RnMS (RenamedContext, FreeVars)
-rnContext doc ctxt
- = mapAndUnzipRn rn_pred ctxt `thenRn` \ (theta, fvs_s) ->
+rnTyClDecl (ClassDecl {tcdCtxt = context, tcdLName = cname,
+ tcdTyVars = tyvars, tcdFDs = fds, tcdSigs = sigs,
+ tcdMeths = mbinds})
+ = lookupLocatedTopBndrRn cname `thenM` \ cname' ->
+
+ -- Tyvars scope over superclass context and method signatures
+ bindTyVarsRn cls_doc tyvars ( \ tyvars' ->
+ rnContext cls_doc context `thenM` \ context' ->
+ rnFds cls_doc fds `thenM` \ fds' ->
+ renameSigs sigs `thenM` \ sigs' ->
+ returnM (tyvars', context', fds', sigs')
+ ) `thenM` \ (tyvars', context', fds', sigs') ->
+
+ -- Check the signatures
+ -- First process the class op sigs (op_sigs), then the fixity sigs (non_op_sigs).
let
- (_, dups) = removeDupsEq theta
- -- We only have equality, not ordering
+ sig_rdr_names_w_locs = [op | L _ (Sig op _) <- sigs]
in
- -- Check for duplicate assertions
- -- If this isn't an error, then it ought to be:
- mapRn (addWarnRn . dupClassAssertWarn theta) dups `thenRn_`
- returnRn (theta, plusFVs fvs_s)
- where
- --Someone discovered that @CCallable@ and @CReturnable@
- -- could be used in contexts such as:
- -- foo :: CCallable a => a -> PrimIO Int
- -- Doing this utterly wrecks the whole point of introducing these
- -- classes so we specifically check that this isn't being done.
- rn_pred pred = rnPred doc pred `thenRn` \ (pred', fvs)->
- checkRn (not (bad_pred pred'))
- (naughtyCCallContextErr pred') `thenRn_`
- returnRn (pred', fvs)
-
- bad_pred (HsPClass clas _) = getUnique clas `elem` cCallishClassKeys
- bad_pred other = False
-
-
-rnPred doc (HsPClass clas tys)
- = lookupOccRn clas `thenRn` \ clas_name ->
- rnHsTypes doc tys `thenRn` \ (tys', fvs) ->
- returnRn (HsPClass clas_name tys', fvs `addOneFV` clas_name)
-
-rnPred doc (HsPIParam n ty)
- = getIPName n `thenRn` \ name ->
- rnHsType doc ty `thenRn` \ (ty', fvs) ->
- returnRn (HsPIParam name ty', fvs)
-\end{code}
-
-\begin{code}
-rnFds :: SDoc -> [FunDep RdrName] -> RnMS ([FunDep Name], FreeVars)
+ checkDupNames sig_doc sig_rdr_names_w_locs `thenM_`
+ checkSigs okClsDclSig sigs' `thenM_`
+ -- Typechecker is responsible for checking that we only
+ -- give default-method bindings for things in this class.
+ -- The renamer *could* check this for class decls, but can't
+ -- for instance decls.
-rnFds doc fds
- = mapAndUnzipRn rn_fds fds `thenRn` \ (theta, fvs_s) ->
- returnRn (theta, plusFVs fvs_s)
+ -- The newLocals call is tiresome: given a generic class decl
+ -- class C a where
+ -- op :: a -> a
+ -- op {| x+y |} (Inl a) = ...
+ -- op {| x+y |} (Inr b) = ...
+ -- op {| a*b |} (a*b) = ...
+ -- we want to name both "x" tyvars with the same unique, so that they are
+ -- easy to group together in the typechecker.
+ extendTyVarEnvForMethodBinds tyvars' (
+ getLocalRdrEnv `thenM` \ name_env ->
+ let
+ meth_rdr_names_w_locs = collectHsBindLocatedBinders mbinds
+ gen_rdr_tyvars_w_locs =
+ [ tv | tv <- extractGenericPatTyVars mbinds,
+ not (unLoc tv `elemLocalRdrEnv` name_env) ]
+ in
+ checkDupNames meth_doc meth_rdr_names_w_locs `thenM_`
+ newLocalsRn gen_rdr_tyvars_w_locs `thenM` \ gen_tyvars ->
+ rnMethodBinds (unLoc cname') gen_tyvars mbinds
+ ) `thenM` \ (mbinds', meth_fvs) ->
+
+ returnM (ClassDecl { tcdCtxt = context', tcdLName = cname', tcdTyVars = tyvars',
+ tcdFDs = fds', tcdSigs = sigs', tcdMeths = mbinds'},
+ delFVs (map hsLTyVarName tyvars') $
+ extractHsCtxtTyNames context' `plusFV`
+ plusFVs (map extractFunDepNames (map unLoc fds')) `plusFV`
+ hsSigsFVs sigs' `plusFV`
+ meth_fvs)
where
- rn_fds (tys1, tys2)
- = rnHsTyVars doc tys1 `thenRn` \ (tys1', fvs1) ->
- rnHsTyVars doc tys2 `thenRn` \ (tys2', fvs2) ->
- returnRn ((tys1', tys2'), fvs1 `plusFV` fvs2)
-
-rnHsTyVars doc tvs = mapFvRn (rnHsTyvar doc) tvs
-rnHsTyvar doc tyvar
- = lookupOccRn tyvar `thenRn` \ tyvar' ->
- returnRn (tyvar', unitFV tyvar')
+ meth_doc = text "In the default-methods for class" <+> ppr cname
+ cls_doc = text "In the declaration for class" <+> ppr cname
+ sig_doc = text "In the signatures for class" <+> ppr cname
\end{code}
%*********************************************************
-%* *
-\subsection{IdInfo}
-%* *
+%* *
+\subsection{Support code for type/data declarations}
+%* *
%*********************************************************
\begin{code}
-rnIdInfo (HsStrictness str) = returnRn (HsStrictness str, emptyFVs)
-
-rnIdInfo (HsWorker worker)
- = lookupOccRn worker `thenRn` \ worker' ->
- returnRn (HsWorker worker', unitFV worker')
-
-rnIdInfo (HsUnfold inline expr) = rnCoreExpr expr `thenRn` \ (expr', fvs) ->
- returnRn (HsUnfold inline expr', fvs)
-rnIdInfo (HsArity arity) = returnRn (HsArity arity, emptyFVs)
-rnIdInfo (HsUpdate update) = returnRn (HsUpdate update, emptyFVs)
-rnIdInfo HsNoCafRefs = returnRn (HsNoCafRefs, emptyFVs)
-rnIdInfo HsCprInfo = returnRn (HsCprInfo, emptyFVs)
-
-\end{code}
-
-@UfCore@ expressions.
-
-\begin{code}
-rnCoreExpr (UfType ty)
- = rnHsType (text "unfolding type") ty `thenRn` \ (ty', fvs) ->
- returnRn (UfType ty', fvs)
-
-rnCoreExpr (UfVar v)
- = lookupOccRn v `thenRn` \ v' ->
- returnRn (UfVar v', unitFV v')
-
-rnCoreExpr (UfLit l)
- = returnRn (UfLit l, emptyFVs)
-
-rnCoreExpr (UfLitLit l ty)
- = rnHsType (text "litlit") ty `thenRn` \ (ty', fvs) ->
- returnRn (UfLitLit l ty', fvs)
-
-rnCoreExpr (UfCCall cc ty)
- = rnHsType (text "ccall") ty `thenRn` \ (ty', fvs) ->
- returnRn (UfCCall cc ty', fvs)
-
-rnCoreExpr (UfTuple con args)
- = rnHsTupConWkr con `thenRn` \ (con', fvs1) ->
- mapFvRn rnCoreExpr args `thenRn` \ (args', fvs2) ->
- returnRn (UfTuple con' args', fvs1 `plusFV` fvs2)
-
-rnCoreExpr (UfApp fun arg)
- = rnCoreExpr fun `thenRn` \ (fun', fv1) ->
- rnCoreExpr arg `thenRn` \ (arg', fv2) ->
- returnRn (UfApp fun' arg', fv1 `plusFV` fv2)
-
-rnCoreExpr (UfCase scrut bndr alts)
- = rnCoreExpr scrut `thenRn` \ (scrut', fvs1) ->
- bindCoreLocalFVRn bndr ( \ bndr' ->
- mapFvRn rnCoreAlt alts `thenRn` \ (alts', fvs2) ->
- returnRn (UfCase scrut' bndr' alts', fvs2)
- ) `thenRn` \ (case', fvs3) ->
- returnRn (case', fvs1 `plusFV` fvs3)
-
-rnCoreExpr (UfNote note expr)
- = rnNote note `thenRn` \ (note', fvs1) ->
- rnCoreExpr expr `thenRn` \ (expr', fvs2) ->
- returnRn (UfNote note' expr', fvs1 `plusFV` fvs2)
-
-rnCoreExpr (UfLam bndr body)
- = rnCoreBndr bndr $ \ bndr' ->
- rnCoreExpr body `thenRn` \ (body', fvs) ->
- returnRn (UfLam bndr' body', fvs)
-
-rnCoreExpr (UfLet (UfNonRec bndr rhs) body)
- = rnCoreExpr rhs `thenRn` \ (rhs', fvs1) ->
- rnCoreBndr bndr ( \ bndr' ->
- rnCoreExpr body `thenRn` \ (body', fvs2) ->
- returnRn (UfLet (UfNonRec bndr' rhs') body', fvs2)
- ) `thenRn` \ (result, fvs3) ->
- returnRn (result, fvs1 `plusFV` fvs3)
-
-rnCoreExpr (UfLet (UfRec pairs) body)
- = rnCoreBndrs bndrs $ \ bndrs' ->
- mapFvRn rnCoreExpr rhss `thenRn` \ (rhss', fvs1) ->
- rnCoreExpr body `thenRn` \ (body', fvs2) ->
- returnRn (UfLet (UfRec (bndrs' `zip` rhss')) body', fvs1 `plusFV` fvs2)
+rnConDecls :: Name -> [LConDecl RdrName] -> RnM [LConDecl Name]
+rnConDecls tycon condecls
+ = -- Check that there's at least one condecl,
+ -- or else we're reading an interface file, or -fglasgow-exts
+ (if null condecls then
+ doptM Opt_GlasgowExts `thenM` \ glaExts ->
+ checkErr glaExts (emptyConDeclsErr tycon)
+ else returnM ()
+ ) `thenM_`
+ mappM (wrapLocM rnConDecl) condecls
+
+rnConDecl :: ConDecl RdrName -> RnM (ConDecl Name)
+rnConDecl (ConDecl name tvs cxt details)
+ = addLocM checkConName name `thenM_`
+ lookupLocatedTopBndrRn name `thenM` \ new_name ->
+
+ bindTyVarsRn doc tvs $ \ new_tyvars ->
+ rnContext doc cxt `thenM` \ new_context ->
+ rnConDetails doc details `thenM` \ new_details ->
+ returnM (ConDecl new_name new_tyvars new_context new_details)
where
- (bndrs, rhss) = unzip pairs
-\end{code}
+ doc = text "In the definition of data constructor" <+> quotes (ppr name)
-\begin{code}
-rnCoreBndr (UfValBinder name ty) thing_inside
- = rnHsType doc ty `thenRn` \ (ty', fvs1) ->
- bindCoreLocalFVRn name ( \ name' ->
- thing_inside (UfValBinder name' ty')
- ) `thenRn` \ (result, fvs2) ->
- returnRn (result, fvs1 `plusFV` fvs2)
+rnConDecl (GadtDecl name ty)
+ = addLocM checkConName name `thenM_`
+ lookupLocatedTopBndrRn name `thenM` \ new_name ->
+ rnHsSigType doc ty `thenM` \ new_ty ->
+ returnM (GadtDecl new_name new_ty)
where
- doc = text "unfolding id"
-
-rnCoreBndr (UfTyBinder name kind) thing_inside
- = bindCoreLocalFVRn name $ \ name' ->
- thing_inside (UfTyBinder name' kind)
-
-rnCoreBndrs [] thing_inside = thing_inside []
-rnCoreBndrs (b:bs) thing_inside = rnCoreBndr b $ \ name' ->
- rnCoreBndrs bs $ \ names' ->
- thing_inside (name':names')
-\end{code}
-
-\begin{code}
-rnCoreAlt (con, bndrs, rhs)
- = rnUfCon con bndrs `thenRn` \ (con', fvs1) ->
- bindCoreLocalsFVRn bndrs ( \ bndrs' ->
- rnCoreExpr rhs `thenRn` \ (rhs', fvs2) ->
- returnRn ((con', bndrs', rhs'), fvs2)
- ) `thenRn` \ (result, fvs3) ->
- returnRn (result, fvs1 `plusFV` fvs3)
+ doc = text "In the definition of data constructor" <+> quotes (ppr name)
-rnNote (UfCoerce ty)
- = rnHsType (text "unfolding coerce") ty `thenRn` \ (ty', fvs) ->
- returnRn (UfCoerce ty', fvs)
+rnConDetails doc (PrefixCon tys)
+ = mappM (rnLHsType doc) tys `thenM` \ new_tys ->
+ returnM (PrefixCon new_tys)
-rnNote (UfSCC cc) = returnRn (UfSCC cc, emptyFVs)
-rnNote UfInlineCall = returnRn (UfInlineCall, emptyFVs)
-rnNote UfInlineMe = returnRn (UfInlineMe, emptyFVs)
+rnConDetails doc (InfixCon ty1 ty2)
+ = rnLHsType doc ty1 `thenM` \ new_ty1 ->
+ rnLHsType doc ty2 `thenM` \ new_ty2 ->
+ returnM (InfixCon new_ty1 new_ty2)
+rnConDetails doc (RecCon fields)
+ = checkDupNames doc field_names `thenM_`
+ mappM (rnField doc) fields `thenM` \ new_fields ->
+ returnM (RecCon new_fields)
+ where
+ field_names = [fld | (fld, _) <- fields]
-rnUfCon UfDefault _
- = returnRn (UfDefault, emptyFVs)
+rnField doc (name, ty)
+ = lookupLocatedTopBndrRn name `thenM` \ new_name ->
+ rnLHsType doc ty `thenM` \ new_ty ->
+ returnM (new_name, new_ty)
-rnUfCon (UfTupleAlt tup_con) bndrs
- = rnHsTupCon tup_con `thenRn` \ (HsTupCon con' _, fvs) ->
- returnRn (UfDataAlt con', fvs)
- -- Makes the type checker a little easier
+-- This data decl will parse OK
+-- data T = a Int
+-- treating "a" as the constructor.
+-- It is really hard to make the parser spot this malformation.
+-- So the renamer has to check that the constructor is legal
+--
+-- We can get an operator as the constructor, even in the prefix form:
+-- data T = :% Int Int
+-- from interface files, which always print in prefix form
-rnUfCon (UfDataAlt con) _
- = lookupOccRn con `thenRn` \ con' ->
- returnRn (UfDataAlt con', unitFV con')
+checkConName name = checkErr (isRdrDataCon name) (badDataCon name)
-rnUfCon (UfLitAlt lit) _
- = returnRn (UfLitAlt lit, emptyFVs)
+badDataCon name
+ = hsep [ptext SLIT("Illegal data constructor name"), quotes (ppr name)]
-rnUfCon (UfLitLitAlt lit ty) _
- = rnHsType (text "litlit") ty `thenRn` \ (ty', fvs) ->
- returnRn (UfLitLitAlt lit ty', fvs)
+emptyConDeclsErr tycon
+ = sep [quotes (ppr tycon) <+> ptext SLIT("has no constructors"),
+ nest 4 (ptext SLIT("(-fglasgow-exts permits this)"))]
\end{code}
+
%*********************************************************
-%* *
-\subsection{Rule shapes}
-%* *
+%* *
+\subsection{Support code to rename types}
+%* *
%*********************************************************
-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.
-
\begin{code}
-validRuleLhs foralls lhs
- = check lhs
+rnFds :: SDoc -> [Located (FunDep RdrName)] -> RnM [Located (FunDep Name)]
+
+rnFds doc fds
+ = mappM (wrapLocM rn_fds) fds
where
- check (HsApp e1 e2) = check e1
- check (HsVar v) | v `notElem` foralls = True
- check other = False
+ rn_fds (tys1, tys2)
+ = rnHsTyVars doc tys1 `thenM` \ tys1' ->
+ rnHsTyVars doc tys2 `thenM` \ tys2' ->
+ returnM (tys1', tys2')
+
+rnHsTyVars doc tvs = mappM (rnHsTyvar doc) tvs
+rnHsTyvar doc tyvar = lookupOccRn tyvar
\end{code}
%*********************************************************
-%* *
-\subsection{Errors}
-%* *
+%* *
+ Splices
+%* *
%*********************************************************
\begin{code}
-derivingNonStdClassErr clas
- = hsep [ptext SLIT("non-standard class"), ppr clas, ptext SLIT("in deriving clause")]
-
-classTyVarNotInOpTyErr clas_tyvar sig
- = hang (hsep [ptext SLIT("Class type variable"),
- quotes (ppr clas_tyvar),
- ptext SLIT("does not appear in method signature")])
- 4 (ppr sig)
-
-badDataCon name
- = hsep [ptext SLIT("Illegal data constructor name"), quotes (ppr name)]
-
-forAllWarn doc ty tyvar
- | not opt_WarnUnusedMatches = returnRn ()
- | otherwise
- = getModeRn `thenRn` \ mode ->
- case mode of {
-#ifndef DEBUG
- InterfaceMode -> returnRn () ; -- Don't warn of unused tyvars in interface files
- -- unless DEBUG is on, in which case it is slightly
- -- informative. They can arise from mkRhsTyLam,
-#endif -- leading to (say) f :: forall a b. [b] -> [b]
- other ->
-
- addWarnRn (
- sep [ptext SLIT("The universally quantified type variable") <+> quotes (ppr tyvar),
- nest 4 (ptext SLIT("does not appear in the type") <+> quotes (ppr ty))]
- $$
- (ptext SLIT("In") <+> doc))
- }
-
-forAllErr doc ty tyvar
- = addErrRn (
- sep [ptext SLIT("The constrained type variable") <+> quotes (ppr tyvar),
- nest 4 (ptext SLIT("does not appear in the type") <+> quotes (ppr ty))]
- $$
- (ptext SLIT("In") <+> doc))
-
-univErr doc constraint ty
- = sep [ptext SLIT("All of the type variable(s) in the constraint")
- <+> quotes (ppr constraint)
- <+> ptext SLIT("are already in scope"),
- nest 4 (ptext SLIT("At least one must be universally quantified here"))
- ]
- $$
- (ptext SLIT("In") <+> doc)
-
-badRuleLhsErr name lhs
- = sep [ptext SLIT("Rule") <+> ptext name <> colon,
- nest 4 (ptext SLIT("Illegal left-hand side:") <+> ppr lhs)]
- $$
- ptext SLIT("LHS must be of form (f e1 .. en) where f is not forall'd")
-
-badRuleVar name var
- = sep [ptext SLIT("Rule") <+> ptext name <> colon,
- ptext SLIT("Forall'd variable") <+> quotes (ppr var) <+>
- ptext SLIT("does not appear on left hand side")]
-
-badExtName :: ExtName -> Message
-badExtName ext_nm
- = sep [quotes (ppr ext_nm) <+> ptext SLIT("is not a valid C identifier")]
-
-dupClassAssertWarn ctxt (assertion : dups)
- = sep [hsep [ptext SLIT("Duplicate class assertion"),
- quotes (ppr assertion),
- ptext SLIT("in the context:")],
- nest 4 (pprHsContext ctxt <+> ptext SLIT("..."))]
-
-naughtyCCallContextErr (HsPClass clas _)
- = sep [ptext SLIT("Can't use class") <+> quotes (ppr clas),
- ptext SLIT("in a context")]
+rnSplice :: HsSplice RdrName -> RnM (HsSplice Name, FreeVars)
+rnSplice (HsSplice n expr)
+ = checkTH expr "splice" `thenM_`
+ getSrcSpanM `thenM` \ loc ->
+ newLocalsRn [L loc n] `thenM` \ [n'] ->
+ rnLExpr expr `thenM` \ (expr', fvs) ->
+ returnM (HsSplice n' expr', fvs)
\end{code}
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