2 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
4 \section[RnSource]{Main pass of renamer}
7 module RnSource ( rnDecl, rnTyClDecl, rnIfaceRuleDecl, rnInstDecl, rnSourceDecls,
8 rnHsType, rnHsSigType, rnHsTypeFVs, rnHsSigTypeFVs
11 #include "HsVersions.h"
15 import HscTypes ( GlobalRdrEnv )
16 import HsTypes ( hsTyVarNames, pprHsContext )
17 import RdrName ( RdrName, isRdrDataCon, rdrNameOcc, mkRdrNameWkr, elemRdrEnv )
18 import RdrHsSyn ( RdrNameContext, RdrNameHsType, RdrNameConDecl, RdrNameTyClDecl,
19 extractRuleBndrsTyVars, extractHsTyRdrTyVars,
20 extractHsCtxtRdrTyVars, extractGenericPatTyVars
25 import RnBinds ( rnTopBinds, rnMethodBinds, renameSigs, renameSigsFVs )
26 import RnEnv ( lookupTopBndrRn, lookupOccRn, newIPName, lookupIfaceName,
27 lookupOrigNames, lookupSysBinder, newLocalsRn,
29 bindTyVarsRn, bindTyVars2Rn,
30 bindTyVarsFV2Rn, extendTyVarEnvFVRn,
31 bindCoreLocalRn, bindCoreLocalsRn, bindLocalNames,
32 checkDupOrQualNames, checkDupNames, mapFvRn
36 import Class ( FunDep, DefMeth (..) )
37 import Name ( Name, OccName, nameOccName, NamedThing(..) )
39 import PrelInfo ( derivableClassKeys, cCallishClassKeys )
40 import PrelNames ( deRefStablePtr_RDR, newStablePtr_RDR,
41 bindIO_RDR, returnIO_RDR
43 import List ( partition, nub )
45 import SrcLoc ( SrcLoc )
46 import CmdLineOpts ( DynFlag(..) )
47 -- Warn of unused for-all'd tyvars
48 import Unique ( Uniquable(..) )
49 import ErrUtils ( Message )
50 import CStrings ( isCLabelString )
51 import ListSetOps ( removeDupsEq )
54 @rnDecl@ `renames' declarations.
55 It simultaneously performs dependency analysis and precedence parsing.
56 It also does the following error checks:
59 Checks that tyvars are used properly. This includes checking
60 for undefined tyvars, and tyvars in contexts that are ambiguous.
61 (Some of this checking has now been moved to module @TcMonoType@,
62 since we don't have functional dependency information at this point.)
64 Checks that all variable occurences are defined.
66 Checks the @(..)@ etc constraints in the export list.
70 %*********************************************************
72 \subsection{Value declarations}
74 %*********************************************************
77 rnSourceDecls :: GlobalRdrEnv -> LocalFixityEnv
79 -> RnMG ([RenamedHsDecl], FreeVars)
80 -- The decls get reversed, but that's ok
82 rnSourceDecls gbl_env local_fixity_env decls
83 = initRnMS gbl_env local_fixity_env SourceMode (go emptyFVs [] decls)
85 -- Fixity and deprecations have been dealt with already; ignore them
86 go fvs ds' [] = returnRn (ds', fvs)
87 go fvs ds' (FixD _:ds) = go fvs ds' ds
88 go fvs ds' (DeprecD _:ds) = go fvs ds' ds
89 go fvs ds' (d:ds) = rnDecl d `thenRn` \(d', fvs') ->
90 go (fvs `plusFV` fvs') (d':ds') ds
94 %*********************************************************
96 \subsection{Value declarations}
98 %*********************************************************
101 -- rnDecl does all the work
102 rnDecl :: RdrNameHsDecl -> RnMS (RenamedHsDecl, FreeVars)
104 rnDecl (ValD binds) = rnTopBinds binds `thenRn` \ (new_binds, fvs) ->
105 returnRn (ValD new_binds, fvs)
107 rnDecl (TyClD tycl_decl)
108 = rnTyClDecl tycl_decl `thenRn` \ new_decl ->
109 rnClassBinds tycl_decl new_decl `thenRn` \ (new_decl', fvs) ->
110 returnRn (TyClD new_decl', fvs `plusFV` tyClDeclFVs new_decl')
113 = rnInstDecl inst `thenRn` \ new_inst ->
114 rnInstBinds inst new_inst `thenRn` \ (new_inst', fvs) ->
115 returnRn (InstD new_inst', fvs `plusFV` instDeclFVs new_inst')
118 | isIfaceRuleDecl rule
119 = rnIfaceRuleDecl rule `thenRn` \ new_rule ->
120 returnRn (RuleD new_rule, ruleDeclFVs new_rule)
122 = rnHsRuleDecl rule `thenRn` \ (new_rule, fvs) ->
123 returnRn (RuleD new_rule, fvs)
125 rnDecl (DefD (DefaultDecl tys src_loc))
126 = pushSrcLocRn src_loc $
127 mapFvRn (rnHsTypeFVs doc_str) tys `thenRn` \ (tys', fvs) ->
128 returnRn (DefD (DefaultDecl tys' src_loc), fvs)
130 doc_str = text "a `default' declaration"
132 rnDecl (ForD (ForeignDecl name imp_exp ty ext_nm cconv src_loc))
133 = pushSrcLocRn src_loc $
134 lookupOccRn name `thenRn` \ name' ->
137 | isDyn = lookupOrigNames [newStablePtr_RDR, deRefStablePtr_RDR,
138 bindIO_RDR, returnIO_RDR]
140 lookupOrigNames [bindIO_RDR, returnIO_RDR] `thenRn` \ fvs ->
141 returnRn (addOneFV fvs name')
142 extra_fvs other = returnRn emptyFVs
144 checkRn (ok_ext_nm ext_nm) (badExtName ext_nm) `thenRn_`
146 extra_fvs imp_exp `thenRn` \ fvs1 ->
148 rnHsTypeFVs fo_decl_msg ty `thenRn` \ (ty', fvs2) ->
149 returnRn (ForD (ForeignDecl name' imp_exp ty' ext_nm cconv src_loc),
152 fo_decl_msg = ptext SLIT("The foreign declaration for") <+> ppr name
153 isDyn = isDynamicExtName ext_nm
155 ok_ext_nm Dynamic = True
156 ok_ext_nm (ExtName nm (Just mb)) = isCLabelString nm && isCLabelString mb
157 ok_ext_nm (ExtName nm Nothing) = isCLabelString nm
161 %*********************************************************
163 \subsection{Instance declarations}
165 %*********************************************************
168 rnInstDecl (InstDecl inst_ty mbinds uprags maybe_dfun_rdr_name src_loc)
169 = pushSrcLocRn src_loc $
170 rnHsSigType (text "an instance decl") inst_ty `thenRn` \ inst_ty' ->
172 (case maybe_dfun_rdr_name of
173 Nothing -> returnRn Nothing
174 Just dfun_rdr_name -> lookupIfaceName dfun_rdr_name `thenRn` \ dfun_name ->
175 returnRn (Just dfun_name)
176 ) `thenRn` \ maybe_dfun_name ->
178 -- The typechecker checks that all the bindings are for the right class.
179 returnRn (InstDecl inst_ty' EmptyMonoBinds [] maybe_dfun_name src_loc)
181 -- Compare rnClassBinds
182 rnInstBinds (InstDecl _ mbinds uprags _ _ )
183 (InstDecl inst_ty _ _ maybe_dfun_rdr_name src_loc)
185 meth_doc = text "the bindings in an instance declaration"
186 meth_names = collectLocatedMonoBinders mbinds
187 inst_tyvars = case inst_ty of
188 HsForAllTy (Just inst_tyvars) _ _ -> inst_tyvars
190 -- (Slightly strangely) the forall-d tyvars scope over
191 -- the method bindings too
194 -- Rename the bindings
195 -- NB meth_names can be qualified!
196 checkDupNames meth_doc meth_names `thenRn_`
197 extendTyVarEnvFVRn (map hsTyVarName inst_tyvars) (
198 rnMethodBinds [] mbinds
199 ) `thenRn` \ (mbinds', meth_fvs) ->
201 binders = collectMonoBinders mbinds'
202 binder_set = mkNameSet binders
204 -- Rename the prags and signatures.
205 -- Note that the type variables are not in scope here,
206 -- so that instance Eq a => Eq (T a) where
207 -- {-# SPECIALISE instance Eq a => Eq (T [a]) #-}
210 -- But the (unqualified) method names are in scope
211 bindLocalNames binders (
212 renameSigsFVs (okInstDclSig binder_set) uprags
213 ) `thenRn` \ (uprags', prag_fvs) ->
215 returnRn (InstDecl inst_ty mbinds' uprags' maybe_dfun_rdr_name src_loc,
216 meth_fvs `plusFV` prag_fvs)
219 %*********************************************************
223 %*********************************************************
226 rnIfaceRuleDecl (IfaceRule rule_name vars fn args rhs src_loc)
227 = pushSrcLocRn src_loc $
228 lookupOccRn fn `thenRn` \ fn' ->
229 rnCoreBndrs vars $ \ vars' ->
230 mapRn rnCoreExpr args `thenRn` \ args' ->
231 rnCoreExpr rhs `thenRn` \ rhs' ->
232 returnRn (IfaceRule rule_name vars' fn' args' rhs' src_loc)
234 rnHsRuleDecl (HsRule rule_name tvs vars lhs rhs src_loc)
236 pushSrcLocRn src_loc $
238 bindTyVarsFV2Rn doc (map UserTyVar sig_tvs) $ \ sig_tvs' _ ->
239 bindLocalsFVRn doc (map get_var vars) $ \ ids ->
240 mapFvRn rn_var (vars `zip` ids) `thenRn` \ (vars', fv_vars) ->
242 rnExpr lhs `thenRn` \ (lhs', fv_lhs) ->
243 rnExpr rhs `thenRn` \ (rhs', fv_rhs) ->
244 checkRn (validRuleLhs ids lhs')
245 (badRuleLhsErr rule_name lhs') `thenRn_`
247 bad_vars = [var | var <- ids, not (var `elemNameSet` fv_lhs)]
249 mapRn (addErrRn . badRuleVar rule_name) bad_vars `thenRn_`
250 returnRn (HsRule rule_name sig_tvs' vars' lhs' rhs' src_loc,
251 fv_vars `plusFV` fv_lhs `plusFV` fv_rhs)
253 doc = text "the transformation rule" <+> ptext rule_name
254 sig_tvs = extractRuleBndrsTyVars vars
256 get_var (RuleBndr v) = v
257 get_var (RuleBndrSig v _) = v
259 rn_var (RuleBndr v, id) = returnRn (RuleBndr id, emptyFVs)
260 rn_var (RuleBndrSig v t, id) = rnHsTypeFVs doc t `thenRn` \ (t', fvs) ->
261 returnRn (RuleBndrSig id t', fvs)
265 %*********************************************************
267 \subsection{Type, class and iface sig declarations}
269 %*********************************************************
271 @rnTyDecl@ uses the `global name function' to create a new type
272 declaration in which local names have been replaced by their original
273 names, reporting any unknown names.
275 Renaming type variables is a pain. Because they now contain uniques,
276 it is necessary to pass in an association list which maps a parsed
277 tyvar to its @Name@ representation.
278 In some cases (type signatures of values),
279 it is even necessary to go over the type first
280 in order to get the set of tyvars used by it, make an assoc list,
281 and then go over it again to rename the tyvars!
282 However, we can also do some scoping checks at the same time.
285 rnTyClDecl (IfaceSig {tcdName = name, tcdType = ty, tcdIdInfo = id_infos, tcdLoc = loc})
287 lookupTopBndrRn name `thenRn` \ name' ->
288 rnHsType doc_str ty `thenRn` \ ty' ->
289 mapRn rnIdInfo id_infos `thenRn` \ id_infos' ->
290 returnRn (IfaceSig {tcdName = name', tcdType = ty', tcdIdInfo = id_infos', tcdLoc = loc})
292 doc_str = text "the interface signature for" <+> quotes (ppr name)
294 rnTyClDecl (TyData {tcdND = new_or_data, tcdCtxt = context, tcdName = tycon,
295 tcdTyVars = tyvars, tcdCons = condecls, tcdNCons = nconstrs,
296 tcdDerivs = derivings, tcdLoc = src_loc, tcdSysNames = sys_names})
297 = pushSrcLocRn src_loc $
298 lookupTopBndrRn tycon `thenRn` \ tycon' ->
299 bindTyVarsRn data_doc tyvars $ \ tyvars' ->
300 rnContext data_doc context `thenRn` \ context' ->
301 checkDupOrQualNames data_doc con_names `thenRn_`
302 mapRn rnConDecl condecls `thenRn` \ condecls' ->
303 mapRn lookupSysBinder sys_names `thenRn` \ sys_names' ->
304 rnDerivs derivings `thenRn` \ derivings' ->
305 returnRn (TyData {tcdND = new_or_data, tcdCtxt = context', tcdName = tycon',
306 tcdTyVars = tyvars', tcdCons = condecls', tcdNCons = nconstrs,
307 tcdDerivs = derivings', tcdLoc = src_loc, tcdSysNames = sys_names'})
309 data_doc = text "the data type declaration for" <+> quotes (ppr tycon)
310 con_names = map conDeclName condecls
312 rnTyClDecl (TySynonym {tcdName = name, tcdTyVars = tyvars, tcdSynRhs = ty, tcdLoc = src_loc})
313 = pushSrcLocRn src_loc $
314 doptRn Opt_GlasgowExts `thenRn` \ glaExts ->
315 lookupTopBndrRn name `thenRn` \ name' ->
316 bindTyVarsRn syn_doc tyvars $ \ tyvars' ->
317 rnHsType syn_doc (unquantify glaExts ty) `thenRn` \ ty' ->
318 returnRn (TySynonym {tcdName = name', tcdTyVars = tyvars', tcdSynRhs = ty', tcdLoc = src_loc})
320 syn_doc = text "the declaration for type synonym" <+> quotes (ppr name)
322 -- For H98 we do *not* universally quantify on the RHS of a synonym
323 -- Silently discard context... but the tyvars in the rest won't be in scope
324 unquantify glaExts (HsForAllTy Nothing ctxt ty) | glaExts = ty
325 unquantify glaExys ty = ty
327 rnTyClDecl (ClassDecl {tcdCtxt = context, tcdName = cname,
328 tcdTyVars = tyvars, tcdFDs = fds, tcdSigs = sigs,
329 tcdSysNames = names, tcdLoc = src_loc})
330 = pushSrcLocRn src_loc $
332 lookupTopBndrRn cname `thenRn` \ cname' ->
334 -- Deal with the implicit tycon and datacon name
335 -- They aren't in scope (because they aren't visible to the user)
336 -- and what we want to do is simply look them up in the cache;
337 -- we jolly well ought to get a 'hit' there!
338 mapRn lookupSysBinder names `thenRn` \ names' ->
340 -- Tyvars scope over bindings and context
341 bindTyVars2Rn cls_doc tyvars $ \ clas_tyvar_names tyvars' ->
343 -- Check the superclasses
344 rnContext cls_doc context `thenRn` \ context' ->
346 -- Check the functional dependencies
347 rnFds cls_doc fds `thenRn` \ fds' ->
349 -- Check the signatures
350 -- First process the class op sigs (op_sigs), then the fixity sigs (non_op_sigs).
352 (op_sigs, non_op_sigs) = partition isClassOpSig sigs
353 sig_rdr_names_w_locs = [(op,locn) | ClassOpSig op _ _ locn <- sigs]
355 checkDupOrQualNames sig_doc sig_rdr_names_w_locs `thenRn_`
356 mapRn (rnClassOp cname' clas_tyvar_names fds') op_sigs `thenRn` \ sigs' ->
358 binders = mkNameSet [ nm | (ClassOpSig nm _ _ _) <- sigs' ]
360 renameSigs (okClsDclSig binders) non_op_sigs `thenRn` \ non_ops' ->
362 -- Typechecker is responsible for checking that we only
363 -- give default-method bindings for things in this class.
364 -- The renamer *could* check this for class decls, but can't
365 -- for instance decls.
367 returnRn (ClassDecl { tcdCtxt = context', tcdName = cname', tcdTyVars = tyvars',
368 tcdFDs = fds', tcdSigs = non_ops' ++ sigs', tcdMeths = Nothing,
369 tcdSysNames = names', tcdLoc = src_loc})
371 cls_doc = text "the declaration for class" <+> ppr cname
372 sig_doc = text "the signatures for class" <+> ppr cname
374 rnClassOp clas clas_tyvars clas_fds sig@(ClassOpSig op dm_stuff ty locn)
375 = pushSrcLocRn locn $
376 lookupTopBndrRn op `thenRn` \ op_name ->
378 -- Check the signature
379 rnHsSigType (quotes (ppr op)) ty `thenRn` \ new_ty ->
381 -- Make the default-method name
384 -> -- Imported class that has a default method decl
385 -- See comments with tname, snames, above
386 lookupSysBinder dm_rdr_name `thenRn` \ dm_name ->
387 returnRn (DefMeth dm_name)
388 -- An imported class decl for a class decl that had an explicit default
389 -- method, mentions, rather than defines,
390 -- the default method, so we must arrange to pull it in
392 GenDefMeth -> returnRn GenDefMeth
393 NoDefMeth -> returnRn NoDefMeth
394 ) `thenRn` \ dm_stuff' ->
396 returnRn (ClassOpSig op_name dm_stuff' new_ty locn)
398 rnClassBinds :: RdrNameTyClDecl -> RenamedTyClDecl -> RnMS (RenamedTyClDecl, FreeVars)
399 rnClassBinds (ClassDecl {tcdMeths = Nothing})
400 rn_cls_decl@(ClassDecl {tcdSigs = sigs})
401 -- No method bindings, so this class decl comes from an interface file,
402 -- However we want to treat the default-method names as free (they should
403 -- be defined somewhere else). [In source code this is not so; the class
404 -- decl will bind whatever default-methods are necessary.]
405 = returnRn (rn_cls_decl, mkFVs [v | ClassOpSig _ (DefMeth v) _ _ <- sigs])
407 rnClassBinds (ClassDecl {tcdMeths = Just mbinds}) -- Get mbinds from here
408 rn_cls_decl@(ClassDecl {tcdTyVars = tyvars, tcdLoc = src_loc}) -- Everything else is here
409 -- There are some default-method bindings (abeit possibly empty) so
410 -- this is a source-code class declaration
411 = -- The newLocals call is tiresome: given a generic class decl
414 -- op {| x+y |} (Inl a) = ...
415 -- op {| x+y |} (Inr b) = ...
416 -- op {| a*b |} (a*b) = ...
417 -- we want to name both "x" tyvars with the same unique, so that they are
418 -- easy to group together in the typechecker.
420 extendTyVarEnvFVRn (map hsTyVarName tyvars) $
421 getLocalNameEnv `thenRn` \ name_env ->
423 meth_rdr_names_w_locs = collectLocatedMonoBinders mbinds
424 gen_rdr_tyvars_w_locs = [(tv,src_loc) | tv <- extractGenericPatTyVars mbinds,
425 not (tv `elemRdrEnv` name_env)]
427 checkDupOrQualNames meth_doc meth_rdr_names_w_locs `thenRn_`
428 newLocalsRn gen_rdr_tyvars_w_locs `thenRn` \ gen_tyvars ->
429 rnMethodBinds gen_tyvars mbinds `thenRn` \ (mbinds', meth_fvs) ->
430 returnRn (rn_cls_decl {tcdMeths = Just mbinds'}, meth_fvs)
432 meth_doc = text "the default-methods for class" <+> ppr (tcdName rn_cls_decl)
434 rnClassBinds _ tycl_decl = returnRn (tycl_decl, emptyFVs)
435 -- Not a class declaration
439 %*********************************************************
441 \subsection{Support code for type/data declarations}
443 %*********************************************************
446 rnDerivs :: Maybe [RdrName] -> RnMS (Maybe [Name])
448 rnDerivs Nothing -- derivs not specified
452 = mapRn do_one clss `thenRn` \ clss' ->
453 returnRn (Just clss')
455 do_one cls = lookupOccRn cls `thenRn` \ clas_name ->
456 checkRn (getUnique clas_name `elem` derivableClassKeys)
457 (derivingNonStdClassErr clas_name) `thenRn_`
462 conDeclName :: RdrNameConDecl -> (RdrName, SrcLoc)
463 conDeclName (ConDecl n _ _ _ _ l) = (n,l)
465 rnConDecl :: RdrNameConDecl -> RnMS RenamedConDecl
466 rnConDecl (ConDecl name wkr tvs cxt details locn)
467 = pushSrcLocRn locn $
468 checkConName name `thenRn_`
469 lookupTopBndrRn name `thenRn` \ new_name ->
471 lookupSysBinder wkr `thenRn` \ new_wkr ->
472 -- See comments with ClassDecl
474 bindTyVarsRn doc tvs $ \ new_tyvars ->
475 rnContext doc cxt `thenRn` \ new_context ->
476 rnConDetails doc locn details `thenRn` \ new_details ->
477 returnRn (ConDecl new_name new_wkr new_tyvars new_context new_details locn)
479 doc = text "the definition of data constructor" <+> quotes (ppr name)
481 rnConDetails doc locn (VanillaCon tys)
482 = mapRn (rnBangTy doc) tys `thenRn` \ new_tys ->
483 returnRn (VanillaCon new_tys)
485 rnConDetails doc locn (InfixCon ty1 ty2)
486 = rnBangTy doc ty1 `thenRn` \ new_ty1 ->
487 rnBangTy doc ty2 `thenRn` \ new_ty2 ->
488 returnRn (InfixCon new_ty1 new_ty2)
490 rnConDetails doc locn (RecCon fields)
491 = checkDupOrQualNames doc field_names `thenRn_`
492 mapRn (rnField doc) fields `thenRn` \ new_fields ->
493 returnRn (RecCon new_fields)
495 field_names = [(fld, locn) | (flds, _) <- fields, fld <- flds]
497 rnField doc (names, ty)
498 = mapRn lookupTopBndrRn names `thenRn` \ new_names ->
499 rnBangTy doc ty `thenRn` \ new_ty ->
500 returnRn (new_names, new_ty)
502 rnBangTy doc (Banged ty)
503 = rnHsType doc ty `thenRn` \ new_ty ->
504 returnRn (Banged new_ty)
506 rnBangTy doc (Unbanged ty)
507 = rnHsType doc ty `thenRn` \ new_ty ->
508 returnRn (Unbanged new_ty)
510 rnBangTy doc (Unpacked ty)
511 = rnHsType doc ty `thenRn` \ new_ty ->
512 returnRn (Unpacked new_ty)
514 -- This data decl will parse OK
516 -- treating "a" as the constructor.
517 -- It is really hard to make the parser spot this malformation.
518 -- So the renamer has to check that the constructor is legal
520 -- We can get an operator as the constructor, even in the prefix form:
521 -- data T = :% Int Int
522 -- from interface files, which always print in prefix form
525 = checkRn (isRdrDataCon name)
530 %*********************************************************
532 \subsection{Support code to rename types}
534 %*********************************************************
537 rnHsTypeFVs :: SDoc -> RdrNameHsType -> RnMS (RenamedHsType, FreeVars)
538 rnHsTypeFVs doc_str ty
539 = rnHsType doc_str ty `thenRn` \ ty' ->
540 returnRn (ty', extractHsTyNames ty')
542 rnHsSigTypeFVs :: SDoc -> RdrNameHsType -> RnMS (RenamedHsType, FreeVars)
543 rnHsSigTypeFVs doc_str ty
544 = rnHsSigType doc_str ty `thenRn` \ ty' ->
545 returnRn (ty', extractHsTyNames ty')
547 rnHsSigType :: SDoc -> RdrNameHsType -> RnMS RenamedHsType
548 -- rnHsSigType is used for source-language type signatures,
549 -- which use *implicit* universal quantification.
550 rnHsSigType doc_str ty
551 = rnHsType (text "the type signature for" <+> doc_str) ty
553 ---------------------------------------
554 rnHsType :: SDoc -> RdrNameHsType -> RnMS RenamedHsType
556 rnHsType doc (HsForAllTy Nothing ctxt ty)
557 -- Implicit quantifiction in source code (no kinds on tyvars)
558 -- Given the signature C => T we universally quantify
559 -- over FV(T) \ {in-scope-tyvars}
560 = getLocalNameEnv `thenRn` \ name_env ->
562 mentioned_in_tau = extractHsTyRdrTyVars ty
563 mentioned_in_ctxt = extractHsCtxtRdrTyVars ctxt
564 mentioned = nub (mentioned_in_tau ++ mentioned_in_ctxt)
565 forall_tyvars = filter (not . (`elemRdrEnv` name_env)) mentioned
567 rnForAll doc (map UserTyVar forall_tyvars) ctxt ty
569 rnHsType doc (HsForAllTy (Just forall_tyvars) ctxt tau)
570 -- Explicit quantification.
571 -- Check that the forall'd tyvars are actually
572 -- mentioned in the type, and produce a warning if not
574 mentioned_in_tau = extractHsTyRdrTyVars tau
575 mentioned_in_ctxt = extractHsCtxtRdrTyVars ctxt
576 mentioned = nub (mentioned_in_tau ++ mentioned_in_ctxt)
577 forall_tyvar_names = hsTyVarNames forall_tyvars
579 -- Explicitly quantified but not mentioned in ctxt or tau
580 warn_guys = filter (`notElem` mentioned) forall_tyvar_names
582 mapRn_ (forAllWarn doc tau) warn_guys `thenRn_`
583 rnForAll doc forall_tyvars ctxt tau
585 rnHsType doc (HsTyVar tyvar)
586 = lookupOccRn tyvar `thenRn` \ tyvar' ->
587 returnRn (HsTyVar tyvar')
589 rnHsType doc (HsOpTy ty1 opname ty2)
590 = lookupOccRn opname `thenRn` \ name' ->
591 rnHsType doc ty1 `thenRn` \ ty1' ->
592 rnHsType doc ty2 `thenRn` \ ty2' ->
593 returnRn (HsOpTy ty1' name' ty2')
595 rnHsType doc (HsNumTy i)
596 | i == 1 = returnRn (HsNumTy i)
597 | otherwise = failWithRn (HsNumTy i)
598 (ptext SLIT("Only unit numeric type pattern is valid"))
600 rnHsType doc (HsFunTy ty1 ty2)
601 = rnHsType doc ty1 `thenRn` \ ty1' ->
602 -- Might find a for-all as the arg of a function type
603 rnHsType doc ty2 `thenRn` \ ty2' ->
604 -- Or as the result. This happens when reading Prelude.hi
605 -- when we find return :: forall m. Monad m -> forall a. a -> m a
606 returnRn (HsFunTy ty1' ty2')
608 rnHsType doc (HsListTy ty)
609 = rnHsType doc ty `thenRn` \ ty' ->
610 returnRn (HsListTy ty')
612 -- Unboxed tuples are allowed to have poly-typed arguments. These
613 -- sometimes crop up as a result of CPR worker-wrappering dictionaries.
614 rnHsType doc (HsTupleTy (HsTupCon _ boxity) tys)
615 -- Don't do lookupOccRn, because this is built-in syntax
616 -- so it doesn't need to be in scope
617 = mapRn (rnHsType doc) tys `thenRn` \ tys' ->
618 returnRn (HsTupleTy (HsTupCon n' boxity) tys')
620 n' = tupleTyCon_name boxity (length tys)
623 rnHsType doc (HsAppTy ty1 ty2)
624 = rnHsType doc ty1 `thenRn` \ ty1' ->
625 rnHsType doc ty2 `thenRn` \ ty2' ->
626 returnRn (HsAppTy ty1' ty2')
628 rnHsType doc (HsPredTy pred)
629 = rnPred doc pred `thenRn` \ pred' ->
630 returnRn (HsPredTy pred')
632 rnHsTypes doc tys = mapRn (rnHsType doc) tys
636 -- We use lookupOcc here because this is interface file only stuff
637 -- and we need the workers...
638 rnHsTupCon (HsTupCon n boxity)
639 = lookupOccRn n `thenRn` \ n' ->
640 returnRn (HsTupCon n' boxity)
642 rnHsTupConWkr (HsTupCon n boxity)
643 -- Tuple construtors are for the *worker* of the tuple
644 -- Going direct saves needless messing about
645 = lookupOccRn (mkRdrNameWkr n) `thenRn` \ n' ->
646 returnRn (HsTupCon n' boxity)
650 rnForAll doc forall_tyvars ctxt ty
651 = bindTyVarsRn doc forall_tyvars $ \ new_tyvars ->
652 rnContext doc ctxt `thenRn` \ new_ctxt ->
653 rnHsType doc ty `thenRn` \ new_ty ->
654 returnRn (mkHsForAllTy (Just new_tyvars) new_ctxt new_ty)
658 rnContext :: SDoc -> RdrNameContext -> RnMS RenamedContext
660 = mapRn rn_pred ctxt `thenRn` \ theta ->
662 (_, dups) = removeDupsEq theta
663 -- We only have equality, not ordering
665 -- Check for duplicate assertions
666 -- If this isn't an error, then it ought to be:
667 mapRn (addWarnRn . dupClassAssertWarn theta) dups `thenRn_`
670 --Someone discovered that @CCallable@ and @CReturnable@
671 -- could be used in contexts such as:
672 -- foo :: CCallable a => a -> PrimIO Int
673 -- Doing this utterly wrecks the whole point of introducing these
674 -- classes so we specifically check that this isn't being done.
675 rn_pred pred = rnPred doc pred `thenRn` \ pred'->
676 checkRn (not (bad_pred pred'))
677 (naughtyCCallContextErr pred') `thenRn_`
680 bad_pred (HsPClass clas _) = getUnique clas `elem` cCallishClassKeys
681 bad_pred other = False
684 rnPred doc (HsPClass clas tys)
685 = lookupOccRn clas `thenRn` \ clas_name ->
686 rnHsTypes doc tys `thenRn` \ tys' ->
687 returnRn (HsPClass clas_name tys')
689 rnPred doc (HsPIParam n ty)
690 = newIPName n `thenRn` \ name ->
691 rnHsType doc ty `thenRn` \ ty' ->
692 returnRn (HsPIParam name ty')
696 rnFds :: SDoc -> [FunDep RdrName] -> RnMS [FunDep Name]
702 = rnHsTyVars doc tys1 `thenRn` \ tys1' ->
703 rnHsTyVars doc tys2 `thenRn` \ tys2' ->
704 returnRn (tys1', tys2')
706 rnHsTyVars doc tvs = mapRn (rnHsTyvar doc) tvs
707 rnHsTyvar doc tyvar = lookupOccRn tyvar
710 %*********************************************************
714 %*********************************************************
717 rnIdInfo (HsWorker worker)
718 = lookupOccRn worker `thenRn` \ worker' ->
719 returnRn (HsWorker worker')
721 rnIdInfo (HsUnfold inline expr) = rnCoreExpr expr `thenRn` \ expr' ->
722 returnRn (HsUnfold inline expr')
723 rnIdInfo (HsStrictness str) = returnRn (HsStrictness str)
724 rnIdInfo (HsArity arity) = returnRn (HsArity arity)
725 rnIdInfo HsNoCafRefs = returnRn HsNoCafRefs
726 rnIdInfo HsCprInfo = returnRn HsCprInfo
729 @UfCore@ expressions.
732 rnCoreExpr (UfType ty)
733 = rnHsType (text "unfolding type") ty `thenRn` \ ty' ->
734 returnRn (UfType ty')
737 = lookupOccRn v `thenRn` \ v' ->
743 rnCoreExpr (UfLitLit l ty)
744 = rnHsType (text "litlit") ty `thenRn` \ ty' ->
745 returnRn (UfLitLit l ty')
747 rnCoreExpr (UfCCall cc ty)
748 = rnHsType (text "ccall") ty `thenRn` \ ty' ->
749 returnRn (UfCCall cc ty')
751 rnCoreExpr (UfTuple con args)
752 = rnHsTupConWkr con `thenRn` \ con' ->
753 mapRn rnCoreExpr args `thenRn` \ args' ->
754 returnRn (UfTuple con' args')
756 rnCoreExpr (UfApp fun arg)
757 = rnCoreExpr fun `thenRn` \ fun' ->
758 rnCoreExpr arg `thenRn` \ arg' ->
759 returnRn (UfApp fun' arg')
761 rnCoreExpr (UfCase scrut bndr alts)
762 = rnCoreExpr scrut `thenRn` \ scrut' ->
763 bindCoreLocalRn bndr $ \ bndr' ->
764 mapRn rnCoreAlt alts `thenRn` \ alts' ->
765 returnRn (UfCase scrut' bndr' alts')
767 rnCoreExpr (UfNote note expr)
768 = rnNote note `thenRn` \ note' ->
769 rnCoreExpr expr `thenRn` \ expr' ->
770 returnRn (UfNote note' expr')
772 rnCoreExpr (UfLam bndr body)
773 = rnCoreBndr bndr $ \ bndr' ->
774 rnCoreExpr body `thenRn` \ body' ->
775 returnRn (UfLam bndr' body')
777 rnCoreExpr (UfLet (UfNonRec bndr rhs) body)
778 = rnCoreExpr rhs `thenRn` \ rhs' ->
779 rnCoreBndr bndr $ \ bndr' ->
780 rnCoreExpr body `thenRn` \ body' ->
781 returnRn (UfLet (UfNonRec bndr' rhs') body')
783 rnCoreExpr (UfLet (UfRec pairs) body)
784 = rnCoreBndrs bndrs $ \ bndrs' ->
785 mapRn rnCoreExpr rhss `thenRn` \ rhss' ->
786 rnCoreExpr body `thenRn` \ body' ->
787 returnRn (UfLet (UfRec (bndrs' `zip` rhss')) body')
789 (bndrs, rhss) = unzip pairs
793 rnCoreBndr (UfValBinder name ty) thing_inside
794 = rnHsType doc ty `thenRn` \ ty' ->
795 bindCoreLocalRn name $ \ name' ->
796 thing_inside (UfValBinder name' ty')
798 doc = text "unfolding id"
800 rnCoreBndr (UfTyBinder name kind) thing_inside
801 = bindCoreLocalRn name $ \ name' ->
802 thing_inside (UfTyBinder name' kind)
804 rnCoreBndrs [] thing_inside = thing_inside []
805 rnCoreBndrs (b:bs) thing_inside = rnCoreBndr b $ \ name' ->
806 rnCoreBndrs bs $ \ names' ->
807 thing_inside (name':names')
811 rnCoreAlt (con, bndrs, rhs)
812 = rnUfCon con bndrs `thenRn` \ con' ->
813 bindCoreLocalsRn bndrs $ \ bndrs' ->
814 rnCoreExpr rhs `thenRn` \ rhs' ->
815 returnRn (con', bndrs', rhs')
818 = rnHsType (text "unfolding coerce") ty `thenRn` \ ty' ->
819 returnRn (UfCoerce ty')
821 rnNote (UfSCC cc) = returnRn (UfSCC cc)
822 rnNote UfInlineCall = returnRn UfInlineCall
823 rnNote UfInlineMe = returnRn UfInlineMe
829 rnUfCon (UfTupleAlt tup_con) bndrs
830 = rnHsTupCon tup_con `thenRn` \ (HsTupCon con' _) ->
831 returnRn (UfDataAlt con')
832 -- Makes the type checker a little easier
834 rnUfCon (UfDataAlt con) _
835 = lookupOccRn con `thenRn` \ con' ->
836 returnRn (UfDataAlt con')
838 rnUfCon (UfLitAlt lit) _
839 = returnRn (UfLitAlt lit)
841 rnUfCon (UfLitLitAlt lit ty) _
842 = rnHsType (text "litlit") ty `thenRn` \ ty' ->
843 returnRn (UfLitLitAlt lit ty')
846 %*********************************************************
848 \subsection{Rule shapes}
850 %*********************************************************
852 Check the shape of a transformation rule LHS. Currently
853 we only allow LHSs of the form @(f e1 .. en)@, where @f@ is
854 not one of the @forall@'d variables.
857 validRuleLhs foralls lhs
860 check (HsApp e1 e2) = check e1
861 check (HsVar v) | v `notElem` foralls = True
866 %*********************************************************
870 %*********************************************************
873 derivingNonStdClassErr clas
874 = hsep [ptext SLIT("non-standard class"), ppr clas, ptext SLIT("in deriving clause")]
877 = hsep [ptext SLIT("Illegal data constructor name"), quotes (ppr name)]
879 forAllWarn doc ty tyvar
880 = doptRn Opt_WarnUnusedMatches `thenRn` \ warn_unused -> case () of
881 () | not warn_unused -> returnRn ()
883 -> getModeRn `thenRn` \ mode ->
886 InterfaceMode -> returnRn () ; -- Don't warn of unused tyvars in interface files
887 -- unless DEBUG is on, in which case it is slightly
888 -- informative. They can arise from mkRhsTyLam,
889 #endif -- leading to (say) f :: forall a b. [b] -> [b]
892 sep [ptext SLIT("The universally quantified type variable") <+> quotes (ppr tyvar),
893 nest 4 (ptext SLIT("does not appear in the type") <+> quotes (ppr ty))]
895 (ptext SLIT("In") <+> doc)
899 badRuleLhsErr name lhs
900 = sep [ptext SLIT("Rule") <+> ptext name <> colon,
901 nest 4 (ptext SLIT("Illegal left-hand side:") <+> ppr lhs)]
903 ptext SLIT("LHS must be of form (f e1 .. en) where f is not forall'd")
906 = sep [ptext SLIT("Rule") <+> ptext name <> colon,
907 ptext SLIT("Forall'd variable") <+> quotes (ppr var) <+>
908 ptext SLIT("does not appear on left hand side")]
910 badExtName :: ExtName -> Message
912 = sep [quotes (ppr ext_nm) <+> ptext SLIT("is not a valid C identifier")]
914 dupClassAssertWarn ctxt (assertion : dups)
915 = sep [hsep [ptext SLIT("Duplicate class assertion"),
916 quotes (ppr assertion),
917 ptext SLIT("in the context:")],
918 nest 4 (pprHsContext ctxt <+> ptext SLIT("..."))]
920 naughtyCCallContextErr (HsPClass clas _)
921 = sep [ptext SLIT("Can't use class") <+> quotes (ppr clas),
922 ptext SLIT("in a context")]