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 -- In interface files all types are quantified, so this is a no-op
325 unquantify glaExts (HsForAllTy Nothing ctxt ty) | glaExts = ty
326 unquantify glaExys ty = ty
328 rnTyClDecl (ClassDecl {tcdCtxt = context, tcdName = cname,
329 tcdTyVars = tyvars, tcdFDs = fds, tcdSigs = sigs,
330 tcdSysNames = names, tcdLoc = src_loc})
331 = pushSrcLocRn src_loc $
333 lookupTopBndrRn cname `thenRn` \ cname' ->
335 -- Deal with the implicit tycon and datacon name
336 -- They aren't in scope (because they aren't visible to the user)
337 -- and what we want to do is simply look them up in the cache;
338 -- we jolly well ought to get a 'hit' there!
339 mapRn lookupSysBinder names `thenRn` \ names' ->
341 -- Tyvars scope over bindings and context
342 bindTyVars2Rn cls_doc tyvars $ \ clas_tyvar_names tyvars' ->
344 -- Check the superclasses
345 rnContext cls_doc context `thenRn` \ context' ->
347 -- Check the functional dependencies
348 rnFds cls_doc fds `thenRn` \ fds' ->
350 -- Check the signatures
351 -- First process the class op sigs (op_sigs), then the fixity sigs (non_op_sigs).
353 (op_sigs, non_op_sigs) = partition isClassOpSig sigs
354 sig_rdr_names_w_locs = [(op,locn) | ClassOpSig op _ _ locn <- sigs]
356 checkDupOrQualNames sig_doc sig_rdr_names_w_locs `thenRn_`
357 mapRn (rnClassOp cname' clas_tyvar_names fds') op_sigs `thenRn` \ sigs' ->
359 binders = mkNameSet [ nm | (ClassOpSig nm _ _ _) <- sigs' ]
361 renameSigs (okClsDclSig binders) non_op_sigs `thenRn` \ non_ops' ->
363 -- Typechecker is responsible for checking that we only
364 -- give default-method bindings for things in this class.
365 -- The renamer *could* check this for class decls, but can't
366 -- for instance decls.
368 returnRn (ClassDecl { tcdCtxt = context', tcdName = cname', tcdTyVars = tyvars',
369 tcdFDs = fds', tcdSigs = non_ops' ++ sigs', tcdMeths = Nothing,
370 tcdSysNames = names', tcdLoc = src_loc})
372 cls_doc = text "the declaration for class" <+> ppr cname
373 sig_doc = text "the signatures for class" <+> ppr cname
375 rnClassOp clas clas_tyvars clas_fds sig@(ClassOpSig op dm_stuff ty locn)
376 = pushSrcLocRn locn $
377 lookupTopBndrRn op `thenRn` \ op_name ->
379 -- Check the signature
380 rnHsSigType (quotes (ppr op)) ty `thenRn` \ new_ty ->
382 -- Make the default-method name
385 -> -- Imported class that has a default method decl
386 -- See comments with tname, snames, above
387 lookupSysBinder dm_rdr_name `thenRn` \ dm_name ->
388 returnRn (DefMeth dm_name)
389 -- An imported class decl for a class decl that had an explicit default
390 -- method, mentions, rather than defines,
391 -- the default method, so we must arrange to pull it in
393 GenDefMeth -> returnRn GenDefMeth
394 NoDefMeth -> returnRn NoDefMeth
395 ) `thenRn` \ dm_stuff' ->
397 returnRn (ClassOpSig op_name dm_stuff' new_ty locn)
399 rnClassBinds :: RdrNameTyClDecl -> RenamedTyClDecl -> RnMS (RenamedTyClDecl, FreeVars)
400 rnClassBinds (ClassDecl {tcdMeths = Nothing})
401 rn_cls_decl@(ClassDecl {tcdSigs = sigs})
402 -- No method bindings, so this class decl comes from an interface file,
403 -- However we want to treat the default-method names as free (they should
404 -- be defined somewhere else). [In source code this is not so; the class
405 -- decl will bind whatever default-methods are necessary.]
406 = returnRn (rn_cls_decl, mkFVs [v | ClassOpSig _ (DefMeth v) _ _ <- sigs])
408 rnClassBinds (ClassDecl {tcdMeths = Just mbinds}) -- Get mbinds from here
409 rn_cls_decl@(ClassDecl {tcdTyVars = tyvars, tcdLoc = src_loc}) -- Everything else is here
410 -- There are some default-method bindings (abeit possibly empty) so
411 -- this is a source-code class declaration
412 = -- The newLocals call is tiresome: given a generic class decl
415 -- op {| x+y |} (Inl a) = ...
416 -- op {| x+y |} (Inr b) = ...
417 -- op {| a*b |} (a*b) = ...
418 -- we want to name both "x" tyvars with the same unique, so that they are
419 -- easy to group together in the typechecker.
421 extendTyVarEnvFVRn (map hsTyVarName tyvars) $
422 getLocalNameEnv `thenRn` \ name_env ->
424 meth_rdr_names_w_locs = collectLocatedMonoBinders mbinds
425 gen_rdr_tyvars_w_locs = [(tv,src_loc) | tv <- extractGenericPatTyVars mbinds,
426 not (tv `elemRdrEnv` name_env)]
428 checkDupOrQualNames meth_doc meth_rdr_names_w_locs `thenRn_`
429 newLocalsRn gen_rdr_tyvars_w_locs `thenRn` \ gen_tyvars ->
430 rnMethodBinds gen_tyvars mbinds `thenRn` \ (mbinds', meth_fvs) ->
431 returnRn (rn_cls_decl {tcdMeths = Just mbinds'}, meth_fvs)
433 meth_doc = text "the default-methods for class" <+> ppr (tcdName rn_cls_decl)
435 rnClassBinds _ tycl_decl = returnRn (tycl_decl, emptyFVs)
436 -- Not a class declaration
440 %*********************************************************
442 \subsection{Support code for type/data declarations}
444 %*********************************************************
447 rnDerivs :: Maybe [RdrName] -> RnMS (Maybe [Name])
449 rnDerivs Nothing -- derivs not specified
453 = mapRn do_one clss `thenRn` \ clss' ->
454 returnRn (Just clss')
456 do_one cls = lookupOccRn cls `thenRn` \ clas_name ->
457 checkRn (getUnique clas_name `elem` derivableClassKeys)
458 (derivingNonStdClassErr clas_name) `thenRn_`
463 conDeclName :: RdrNameConDecl -> (RdrName, SrcLoc)
464 conDeclName (ConDecl n _ _ _ _ l) = (n,l)
466 rnConDecl :: RdrNameConDecl -> RnMS RenamedConDecl
467 rnConDecl (ConDecl name wkr tvs cxt details locn)
468 = pushSrcLocRn locn $
469 checkConName name `thenRn_`
470 lookupTopBndrRn name `thenRn` \ new_name ->
472 lookupSysBinder wkr `thenRn` \ new_wkr ->
473 -- See comments with ClassDecl
475 bindTyVarsRn doc tvs $ \ new_tyvars ->
476 rnContext doc cxt `thenRn` \ new_context ->
477 rnConDetails doc locn details `thenRn` \ new_details ->
478 returnRn (ConDecl new_name new_wkr new_tyvars new_context new_details locn)
480 doc = text "the definition of data constructor" <+> quotes (ppr name)
482 rnConDetails doc locn (VanillaCon tys)
483 = mapRn (rnBangTy doc) tys `thenRn` \ new_tys ->
484 returnRn (VanillaCon new_tys)
486 rnConDetails doc locn (InfixCon ty1 ty2)
487 = rnBangTy doc ty1 `thenRn` \ new_ty1 ->
488 rnBangTy doc ty2 `thenRn` \ new_ty2 ->
489 returnRn (InfixCon new_ty1 new_ty2)
491 rnConDetails doc locn (RecCon fields)
492 = checkDupOrQualNames doc field_names `thenRn_`
493 mapRn (rnField doc) fields `thenRn` \ new_fields ->
494 returnRn (RecCon new_fields)
496 field_names = [(fld, locn) | (flds, _) <- fields, fld <- flds]
498 rnField doc (names, ty)
499 = mapRn lookupTopBndrRn names `thenRn` \ new_names ->
500 rnBangTy doc ty `thenRn` \ new_ty ->
501 returnRn (new_names, new_ty)
503 rnBangTy doc (Banged ty)
504 = rnHsType doc ty `thenRn` \ new_ty ->
505 returnRn (Banged new_ty)
507 rnBangTy doc (Unbanged ty)
508 = rnHsType doc ty `thenRn` \ new_ty ->
509 returnRn (Unbanged new_ty)
511 rnBangTy doc (Unpacked ty)
512 = rnHsType doc ty `thenRn` \ new_ty ->
513 returnRn (Unpacked new_ty)
515 -- This data decl will parse OK
517 -- treating "a" as the constructor.
518 -- It is really hard to make the parser spot this malformation.
519 -- So the renamer has to check that the constructor is legal
521 -- We can get an operator as the constructor, even in the prefix form:
522 -- data T = :% Int Int
523 -- from interface files, which always print in prefix form
526 = checkRn (isRdrDataCon name)
531 %*********************************************************
533 \subsection{Support code to rename types}
535 %*********************************************************
538 rnHsTypeFVs :: SDoc -> RdrNameHsType -> RnMS (RenamedHsType, FreeVars)
539 rnHsTypeFVs doc_str ty
540 = rnHsType doc_str ty `thenRn` \ ty' ->
541 returnRn (ty', extractHsTyNames ty')
543 rnHsSigTypeFVs :: SDoc -> RdrNameHsType -> RnMS (RenamedHsType, FreeVars)
544 rnHsSigTypeFVs doc_str ty
545 = rnHsSigType doc_str ty `thenRn` \ ty' ->
546 returnRn (ty', extractHsTyNames ty')
548 rnHsSigType :: SDoc -> RdrNameHsType -> RnMS RenamedHsType
549 -- rnHsSigType is used for source-language type signatures,
550 -- which use *implicit* universal quantification.
551 rnHsSigType doc_str ty
552 = rnHsType (text "the type signature for" <+> doc_str) ty
554 ---------------------------------------
555 rnHsType :: SDoc -> RdrNameHsType -> RnMS RenamedHsType
557 rnHsType doc (HsForAllTy Nothing ctxt ty)
558 -- Implicit quantifiction in source code (no kinds on tyvars)
559 -- Given the signature C => T we universally quantify
560 -- over FV(T) \ {in-scope-tyvars}
561 = getLocalNameEnv `thenRn` \ name_env ->
563 mentioned_in_tau = extractHsTyRdrTyVars ty
564 mentioned_in_ctxt = extractHsCtxtRdrTyVars ctxt
565 mentioned = nub (mentioned_in_tau ++ mentioned_in_ctxt)
566 forall_tyvars = filter (not . (`elemRdrEnv` name_env)) mentioned
568 rnForAll doc (map UserTyVar forall_tyvars) ctxt ty
570 rnHsType doc (HsForAllTy (Just forall_tyvars) ctxt tau)
571 -- Explicit quantification.
572 -- Check that the forall'd tyvars are actually
573 -- mentioned in the type, and produce a warning if not
575 mentioned_in_tau = extractHsTyRdrTyVars tau
576 mentioned_in_ctxt = extractHsCtxtRdrTyVars ctxt
577 mentioned = nub (mentioned_in_tau ++ mentioned_in_ctxt)
578 forall_tyvar_names = hsTyVarNames forall_tyvars
580 -- Explicitly quantified but not mentioned in ctxt or tau
581 warn_guys = filter (`notElem` mentioned) forall_tyvar_names
583 mapRn_ (forAllWarn doc tau) warn_guys `thenRn_`
584 rnForAll doc forall_tyvars ctxt tau
586 rnHsType doc (HsTyVar tyvar)
587 = lookupOccRn tyvar `thenRn` \ tyvar' ->
588 returnRn (HsTyVar tyvar')
590 rnHsType doc (HsOpTy ty1 opname ty2)
591 = lookupOccRn opname `thenRn` \ name' ->
592 rnHsType doc ty1 `thenRn` \ ty1' ->
593 rnHsType doc ty2 `thenRn` \ ty2' ->
594 returnRn (HsOpTy ty1' name' ty2')
596 rnHsType doc (HsNumTy i)
597 | i == 1 = returnRn (HsNumTy i)
598 | otherwise = failWithRn (HsNumTy i)
599 (ptext SLIT("Only unit numeric type pattern is valid"))
601 rnHsType doc (HsFunTy ty1 ty2)
602 = rnHsType doc ty1 `thenRn` \ ty1' ->
603 -- Might find a for-all as the arg of a function type
604 rnHsType doc ty2 `thenRn` \ ty2' ->
605 -- Or as the result. This happens when reading Prelude.hi
606 -- when we find return :: forall m. Monad m -> forall a. a -> m a
607 returnRn (HsFunTy ty1' ty2')
609 rnHsType doc (HsListTy ty)
610 = rnHsType doc ty `thenRn` \ ty' ->
611 returnRn (HsListTy ty')
613 -- Unboxed tuples are allowed to have poly-typed arguments. These
614 -- sometimes crop up as a result of CPR worker-wrappering dictionaries.
615 rnHsType doc (HsTupleTy (HsTupCon _ boxity) tys)
616 -- Don't do lookupOccRn, because this is built-in syntax
617 -- so it doesn't need to be in scope
618 = mapRn (rnHsType doc) tys `thenRn` \ tys' ->
619 returnRn (HsTupleTy (HsTupCon n' boxity) tys')
621 n' = tupleTyCon_name boxity (length tys)
624 rnHsType doc (HsAppTy ty1 ty2)
625 = rnHsType doc ty1 `thenRn` \ ty1' ->
626 rnHsType doc ty2 `thenRn` \ ty2' ->
627 returnRn (HsAppTy ty1' ty2')
629 rnHsType doc (HsPredTy pred)
630 = rnPred doc pred `thenRn` \ pred' ->
631 returnRn (HsPredTy pred')
633 rnHsTypes doc tys = mapRn (rnHsType doc) tys
637 -- We use lookupOcc here because this is interface file only stuff
638 -- and we need the workers...
639 rnHsTupCon (HsTupCon n boxity)
640 = lookupOccRn n `thenRn` \ n' ->
641 returnRn (HsTupCon n' boxity)
643 rnHsTupConWkr (HsTupCon n boxity)
644 -- Tuple construtors are for the *worker* of the tuple
645 -- Going direct saves needless messing about
646 = lookupOccRn (mkRdrNameWkr n) `thenRn` \ n' ->
647 returnRn (HsTupCon n' boxity)
651 rnForAll doc forall_tyvars ctxt ty
652 = bindTyVarsRn doc forall_tyvars $ \ new_tyvars ->
653 rnContext doc ctxt `thenRn` \ new_ctxt ->
654 rnHsType doc ty `thenRn` \ new_ty ->
655 returnRn (mkHsForAllTy (Just new_tyvars) new_ctxt new_ty)
659 rnContext :: SDoc -> RdrNameContext -> RnMS RenamedContext
661 = mapRn rn_pred ctxt `thenRn` \ theta ->
663 (_, dups) = removeDupsEq theta
664 -- We only have equality, not ordering
666 -- Check for duplicate assertions
667 -- If this isn't an error, then it ought to be:
668 mapRn (addWarnRn . dupClassAssertWarn theta) dups `thenRn_`
671 --Someone discovered that @CCallable@ and @CReturnable@
672 -- could be used in contexts such as:
673 -- foo :: CCallable a => a -> PrimIO Int
674 -- Doing this utterly wrecks the whole point of introducing these
675 -- classes so we specifically check that this isn't being done.
676 rn_pred pred = rnPred doc pred `thenRn` \ pred'->
677 checkRn (not (bad_pred pred'))
678 (naughtyCCallContextErr pred') `thenRn_`
681 bad_pred (HsPClass clas _) = getUnique clas `elem` cCallishClassKeys
682 bad_pred other = False
685 rnPred doc (HsPClass clas tys)
686 = lookupOccRn clas `thenRn` \ clas_name ->
687 rnHsTypes doc tys `thenRn` \ tys' ->
688 returnRn (HsPClass clas_name tys')
690 rnPred doc (HsPIParam n ty)
691 = newIPName n `thenRn` \ name ->
692 rnHsType doc ty `thenRn` \ ty' ->
693 returnRn (HsPIParam name ty')
697 rnFds :: SDoc -> [FunDep RdrName] -> RnMS [FunDep Name]
703 = rnHsTyVars doc tys1 `thenRn` \ tys1' ->
704 rnHsTyVars doc tys2 `thenRn` \ tys2' ->
705 returnRn (tys1', tys2')
707 rnHsTyVars doc tvs = mapRn (rnHsTyvar doc) tvs
708 rnHsTyvar doc tyvar = lookupOccRn tyvar
711 %*********************************************************
715 %*********************************************************
718 rnIdInfo (HsWorker worker)
719 = lookupOccRn worker `thenRn` \ worker' ->
720 returnRn (HsWorker worker')
722 rnIdInfo (HsUnfold inline expr) = rnCoreExpr expr `thenRn` \ expr' ->
723 returnRn (HsUnfold inline expr')
724 rnIdInfo (HsStrictness str) = returnRn (HsStrictness str)
725 rnIdInfo (HsArity arity) = returnRn (HsArity arity)
726 rnIdInfo HsNoCafRefs = returnRn HsNoCafRefs
727 rnIdInfo HsCprInfo = returnRn HsCprInfo
730 @UfCore@ expressions.
733 rnCoreExpr (UfType ty)
734 = rnHsType (text "unfolding type") ty `thenRn` \ ty' ->
735 returnRn (UfType ty')
738 = lookupOccRn v `thenRn` \ v' ->
744 rnCoreExpr (UfLitLit l ty)
745 = rnHsType (text "litlit") ty `thenRn` \ ty' ->
746 returnRn (UfLitLit l ty')
748 rnCoreExpr (UfCCall cc ty)
749 = rnHsType (text "ccall") ty `thenRn` \ ty' ->
750 returnRn (UfCCall cc ty')
752 rnCoreExpr (UfTuple con args)
753 = rnHsTupConWkr con `thenRn` \ con' ->
754 mapRn rnCoreExpr args `thenRn` \ args' ->
755 returnRn (UfTuple con' args')
757 rnCoreExpr (UfApp fun arg)
758 = rnCoreExpr fun `thenRn` \ fun' ->
759 rnCoreExpr arg `thenRn` \ arg' ->
760 returnRn (UfApp fun' arg')
762 rnCoreExpr (UfCase scrut bndr alts)
763 = rnCoreExpr scrut `thenRn` \ scrut' ->
764 bindCoreLocalRn bndr $ \ bndr' ->
765 mapRn rnCoreAlt alts `thenRn` \ alts' ->
766 returnRn (UfCase scrut' bndr' alts')
768 rnCoreExpr (UfNote note expr)
769 = rnNote note `thenRn` \ note' ->
770 rnCoreExpr expr `thenRn` \ expr' ->
771 returnRn (UfNote note' expr')
773 rnCoreExpr (UfLam bndr body)
774 = rnCoreBndr bndr $ \ bndr' ->
775 rnCoreExpr body `thenRn` \ body' ->
776 returnRn (UfLam bndr' body')
778 rnCoreExpr (UfLet (UfNonRec bndr rhs) body)
779 = rnCoreExpr rhs `thenRn` \ rhs' ->
780 rnCoreBndr bndr $ \ bndr' ->
781 rnCoreExpr body `thenRn` \ body' ->
782 returnRn (UfLet (UfNonRec bndr' rhs') body')
784 rnCoreExpr (UfLet (UfRec pairs) body)
785 = rnCoreBndrs bndrs $ \ bndrs' ->
786 mapRn rnCoreExpr rhss `thenRn` \ rhss' ->
787 rnCoreExpr body `thenRn` \ body' ->
788 returnRn (UfLet (UfRec (bndrs' `zip` rhss')) body')
790 (bndrs, rhss) = unzip pairs
794 rnCoreBndr (UfValBinder name ty) thing_inside
795 = rnHsType doc ty `thenRn` \ ty' ->
796 bindCoreLocalRn name $ \ name' ->
797 thing_inside (UfValBinder name' ty')
799 doc = text "unfolding id"
801 rnCoreBndr (UfTyBinder name kind) thing_inside
802 = bindCoreLocalRn name $ \ name' ->
803 thing_inside (UfTyBinder name' kind)
805 rnCoreBndrs [] thing_inside = thing_inside []
806 rnCoreBndrs (b:bs) thing_inside = rnCoreBndr b $ \ name' ->
807 rnCoreBndrs bs $ \ names' ->
808 thing_inside (name':names')
812 rnCoreAlt (con, bndrs, rhs)
813 = rnUfCon con bndrs `thenRn` \ con' ->
814 bindCoreLocalsRn bndrs $ \ bndrs' ->
815 rnCoreExpr rhs `thenRn` \ rhs' ->
816 returnRn (con', bndrs', rhs')
819 = rnHsType (text "unfolding coerce") ty `thenRn` \ ty' ->
820 returnRn (UfCoerce ty')
822 rnNote (UfSCC cc) = returnRn (UfSCC cc)
823 rnNote UfInlineCall = returnRn UfInlineCall
824 rnNote UfInlineMe = returnRn UfInlineMe
830 rnUfCon (UfTupleAlt tup_con) bndrs
831 = rnHsTupCon tup_con `thenRn` \ (HsTupCon con' _) ->
832 returnRn (UfDataAlt con')
833 -- Makes the type checker a little easier
835 rnUfCon (UfDataAlt con) _
836 = lookupOccRn con `thenRn` \ con' ->
837 returnRn (UfDataAlt con')
839 rnUfCon (UfLitAlt lit) _
840 = returnRn (UfLitAlt lit)
842 rnUfCon (UfLitLitAlt lit ty) _
843 = rnHsType (text "litlit") ty `thenRn` \ ty' ->
844 returnRn (UfLitLitAlt lit ty')
847 %*********************************************************
849 \subsection{Rule shapes}
851 %*********************************************************
853 Check the shape of a transformation rule LHS. Currently
854 we only allow LHSs of the form @(f e1 .. en)@, where @f@ is
855 not one of the @forall@'d variables.
858 validRuleLhs foralls lhs
861 check (HsApp e1 e2) = check e1
862 check (HsVar v) | v `notElem` foralls = True
867 %*********************************************************
871 %*********************************************************
874 derivingNonStdClassErr clas
875 = hsep [ptext SLIT("non-standard class"), ppr clas, ptext SLIT("in deriving clause")]
878 = hsep [ptext SLIT("Illegal data constructor name"), quotes (ppr name)]
880 forAllWarn doc ty tyvar
881 = doptRn Opt_WarnUnusedMatches `thenRn` \ warn_unused -> case () of
882 () | not warn_unused -> returnRn ()
884 -> getModeRn `thenRn` \ mode ->
887 InterfaceMode -> returnRn () ; -- Don't warn of unused tyvars in interface files
888 -- unless DEBUG is on, in which case it is slightly
889 -- informative. They can arise from mkRhsTyLam,
890 #endif -- leading to (say) f :: forall a b. [b] -> [b]
893 sep [ptext SLIT("The universally quantified type variable") <+> quotes (ppr tyvar),
894 nest 4 (ptext SLIT("does not appear in the type") <+> quotes (ppr ty))]
896 (ptext SLIT("In") <+> doc)
900 badRuleLhsErr name lhs
901 = sep [ptext SLIT("Rule") <+> ptext name <> colon,
902 nest 4 (ptext SLIT("Illegal left-hand side:") <+> ppr lhs)]
904 ptext SLIT("LHS must be of form (f e1 .. en) where f is not forall'd")
907 = sep [ptext SLIT("Rule") <+> ptext name <> colon,
908 ptext SLIT("Forall'd variable") <+> quotes (ppr var) <+>
909 ptext SLIT("does not appear on left hand side")]
911 badExtName :: ExtName -> Message
913 = sep [quotes (ppr ext_nm) <+> ptext SLIT("is not a valid C identifier")]
915 dupClassAssertWarn ctxt (assertion : dups)
916 = sep [hsep [ptext SLIT("Duplicate class assertion"),
917 quotes (ppr assertion),
918 ptext SLIT("in the context:")],
919 nest 4 (pprHsContext ctxt <+> ptext SLIT("..."))]
921 naughtyCCallContextErr (HsPClass clas _)
922 = sep [ptext SLIT("Can't use class") <+> quotes (ppr clas),
923 ptext SLIT("in a context")]