2 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
4 \section[RnSource]{Main pass of renamer}
7 module RnSource ( rnDecl, rnTyClDecl, rnRuleDecl, rnInstDecl, rnSourceDecls,
8 rnHsType, rnHsSigType, rnHsTypeFVs, rnHsSigTypeFVs
11 #include "HsVersions.h"
15 import HsTypes ( hsTyVarNames, pprHsContext )
16 import RdrName ( RdrName, isRdrDataCon, rdrNameOcc, mkRdrNameWkr, elemRdrEnv )
17 import RdrHsSyn ( RdrNameContext, RdrNameHsType, RdrNameConDecl,
18 extractRuleBndrsTyVars, extractHsTyRdrTyVars,
19 extractHsCtxtRdrTyVars, extractGenericPatTyVars
24 import RnBinds ( rnTopBinds, rnMethodBinds, renameSigs )
25 import RnEnv ( lookupTopBndrRn, lookupOccRn, newIPName,
26 lookupOrigNames, lookupSysBinder, newLocalsRn,
27 bindLocalsFVRn, bindUVarRn,
28 bindTyVarsFVRn, bindTyVarsFV2Rn, extendTyVarEnvFVRn,
29 bindCoreLocalFVRn, bindCoreLocalsFVRn, bindLocalNames,
30 checkDupOrQualNames, checkDupNames,
31 FreeVars, emptyFVs, plusFV, plusFVs, unitFV,
36 import Class ( FunDep, DefMeth (..) )
37 import Name ( Name, OccName, nameOccName, NamedThing(..) )
39 import PrelInfo ( derivableClassKeys, cCallishClassKeys )
40 import PrelNames ( deRefStablePtr_RDR, makeStablePtr_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 :: [RdrNameHsDecl] -> RnMS ([RenamedHsDecl], FreeVars)
78 -- The decls get reversed, but that's ok
81 = go emptyFVs [] decls
83 -- Fixity and deprecations have been dealt with already; ignore them
84 go fvs ds' [] = returnRn (ds', fvs)
85 go fvs ds' (FixD _:ds) = go fvs ds' ds
86 go fvs ds' (DeprecD _:ds) = go fvs ds' ds
87 go fvs ds' (d:ds) = rnDecl d `thenRn` \(d', fvs') ->
88 go (fvs `plusFV` fvs') (d':ds') ds
92 %*********************************************************
94 \subsection{Value declarations}
96 %*********************************************************
99 -- rnDecl does all the work
100 rnDecl :: RdrNameHsDecl -> RnMS (RenamedHsDecl, FreeVars)
102 rnDecl (ValD binds) = rnTopBinds binds `thenRn` \ (new_binds, fvs) ->
103 returnRn (ValD new_binds, fvs)
105 rnDecl (TyClD tycl_decl)
106 = rnTyClDecl tycl_decl `thenRn` \ new_decl ->
107 rnClassBinds new_decl `thenRn` \ (new_decl', fvs) ->
108 returnRn (TyClD new_decl', fvs `plusFV` tyClDeclFVs new_decl')
111 = rnInstDecl inst `thenRn` \ new_inst ->
112 rnInstBinds new_inst `thenRn` \ (new_inst', fvs)
113 returnRn (InstD new_inst, fvs `plusFV` instDeclFVs new_inst')
116 | isIfaceRuleDecl rule
117 = rnIfaceRuleDecl rule `thenRn` \ new_rule ->
118 returnRn (RuleD new_rule, ruleDeclFVs new_rule)
122 rnDecl (DefD (DefaultDecl tys src_loc))
123 = pushSrcLocRn src_loc $
124 mapFvRn (rnHsTypeFVs doc_str) tys `thenRn` \ (tys', fvs) ->
125 returnRn (DefD (DefaultDecl tys' src_loc), fvs)
127 doc_str = text "a `default' declaration"
129 rnDecl (ForD (ForeignDecl name imp_exp ty ext_nm cconv src_loc))
130 = pushSrcLocRn src_loc $
131 lookupOccRn name `thenRn` \ name' ->
134 | isDyn = lookupOrigNames [makeStablePtr_RDR, deRefStablePtr_RDR,
135 bindIO_RDR, returnIO_RDR]
137 lookupOrigNames [bindIO_RDR, returnIO_RDR] `thenRn` \ fvs ->
138 returnRn (addOneFV fvs name')
139 extra_fvs other = returnRn emptyFVs
141 checkRn (ok_ext_nm ext_nm) (badExtName ext_nm) `thenRn_`
143 extra_fvs imp_exp `thenRn` \ fvs1 ->
145 rnHsTypeFVs fo_decl_msg ty `thenRn` \ (ty', fvs2) ->
146 returnRn (ForD (ForeignDecl name' imp_exp ty' ext_nm cconv src_loc),
149 fo_decl_msg = ptext SLIT("The foreign declaration for") <+> ppr name
150 isDyn = isDynamicExtName ext_nm
152 ok_ext_nm Dynamic = True
153 ok_ext_nm (ExtName nm (Just mb)) = isCLabelString nm && isCLabelString mb
154 ok_ext_nm (ExtName nm Nothing) = isCLabelString nm
158 %*********************************************************
160 \subsection{Instance declarations}
162 %*********************************************************
165 rnInstDecl (InstDecl inst_ty mbinds uprags maybe_dfun_rdr_name src_loc)
166 = pushSrcLocRn src_loc $
167 rnHsSigType (text "an instance decl") inst_ty `thenRn` \ inst_ty' ->
169 (case maybe_dfun_rdr_name of
170 Nothing -> returnRn Nothing
171 Just dfun_rdr_name -> lookupSysBinder dfun_rdr_name `thenRn` \ dfun_name ->
172 returnRn (Just dfun_name)
173 ) `thenRn` \ maybe_dfun_name ->
175 -- The typechecker checks that all the bindings are for the right class.
176 returnRn (InstDecl inst_ty' mbinds' new_uprags maybe_dfun_name src_loc)
178 meth_doc = text "the bindings in an instance declaration"
179 meth_names = collectLocatedMonoBinders mbinds
181 -- Compare rnClassBinds
182 rnInstBinds (InstDecl _ mbinds uprags _ _ )
183 (InstDecl inst_ty mbinds uprags maybe_dfun_rdr_name src_loc)
185 inst_tyvars = case inst_ty of
186 HsForAllTy (Just inst_tyvars) _ _ -> inst_tyvars
188 -- (Slightly strangely) the forall-d tyvars scope over
189 -- the method bindings too
192 -- Rename the bindings
193 -- NB meth_names can be qualified!
194 checkDupNames meth_doc meth_names `thenRn_`
195 extendTyVarEnvFVRn (map hsTyVarName inst_tyvars) (
196 rnMethodBinds [] mbinds
197 ) `thenRn` \ (mbinds', meth_fvs) ->
199 binders = collectMonoBinders mbinds'
200 binder_set = mkNameSet binders
202 -- Rename the prags and signatures.
203 -- Note that the type variables are not in scope here,
204 -- so that instance Eq a => Eq (T a) where
205 -- {-# SPECIALISE instance Eq a => Eq (T [a]) #-}
208 -- But the (unqualified) method names are in scope
209 bindLocalNames binders (
210 renameSigs (okInstDclSig binder_set) uprags
211 ) `thenRn` \ (uprags', prag_fvs) ->
213 returnRn (InstDecl inst_ty mbinds' uprags' maybe_dfun_rdr_name src_loc,
214 meth_fvs `plusFV` prag_fvs)
217 %*********************************************************
221 %*********************************************************
224 rnIfaceRuleDecl (IfaceRule rule_name vars fn args rhs src_loc)
225 = pushSrcLocRn src_loc $
226 lookupOccRn fn `thenRn` \ fn' ->
227 rnCoreBndrs vars $ \ vars' ->
228 mapFvRn rnCoreExpr args `thenRn` \ args' ->
229 rnCoreExpr rhs `thenRn` \ rhs' ->
230 returnRn (IfaceRule rule_name vars' fn' args' rhs' src_loc)
232 rnHsRuleDecl (HsRule rule_name tvs vars lhs rhs src_loc)
234 pushSrcLocRn src_loc $
236 bindTyVarsFV2Rn doc (map UserTyVar sig_tvs) $ \ sig_tvs' _ ->
237 bindLocalsFVRn doc (map get_var vars) $ \ ids ->
238 mapFvRn rn_var (vars `zip` ids) `thenRn` \ (vars', fv_vars) ->
240 rnExpr lhs `thenRn` \ (lhs', fv_lhs) ->
241 rnExpr rhs `thenRn` \ (rhs', fv_rhs) ->
242 checkRn (validRuleLhs ids lhs')
243 (badRuleLhsErr rule_name lhs') `thenRn_`
245 bad_vars = [var | var <- ids, not (var `elemNameSet` fv_lhs)]
247 mapRn (addErrRn . badRuleVar rule_name) bad_vars `thenRn_`
248 returnRn (HsRule rule_name sig_tvs' vars' lhs' rhs' src_loc,
249 fv_vars `plusFV` fv_lhs `plusFV` fv_rhs)
251 doc = text "the transformation rule" <+> ptext rule_name
252 sig_tvs = extractRuleBndrsTyVars vars
254 get_var (RuleBndr v) = v
255 get_var (RuleBndrSig v _) = v
257 rn_var (RuleBndr v, id) = returnRn (RuleBndr id, emptyFVs)
258 rn_var (RuleBndrSig v t, id) = rnHsTypeFVs doc t `thenRn` \ (t', fvs) ->
259 returnRn (RuleBndrSig id t', fvs)
263 %*********************************************************
265 \subsection{Type, class and iface sig declarations}
267 %*********************************************************
269 @rnTyDecl@ uses the `global name function' to create a new type
270 declaration in which local names have been replaced by their original
271 names, reporting any unknown names.
273 Renaming type variables is a pain. Because they now contain uniques,
274 it is necessary to pass in an association list which maps a parsed
275 tyvar to its @Name@ representation.
276 In some cases (type signatures of values),
277 it is even necessary to go over the type first
278 in order to get the set of tyvars used by it, make an assoc list,
279 and then go over it again to rename the tyvars!
280 However, we can also do some scoping checks at the same time.
283 rnTyClDecl (IfaceSig name ty id_infos loc)
285 lookupTopBndrRn name `thenRn` \ name' ->
286 rnHsType doc_str ty `thenRn` \ ty' ->
287 mapRn rnIdInfo id_infos `thenRn` \ id_infos' ->
288 returnRn (IfaceSig name' ty' id_infos' loc)
290 doc_str = text "the interface signature for" <+> quotes (ppr name)
292 rnTyClDecl (TyData new_or_data context tycon tyvars condecls nconstrs derivings src_loc gen_name1 gen_name2)
293 = pushSrcLocRn src_loc $
294 lookupTopBndrRn tycon `thenRn` \ tycon' ->
295 bindTyVarsRn data_doc tyvars $ \ tyvars' ->
296 rnContext data_doc context `thenRn` \ context' ->
297 checkDupOrQualNames data_doc con_names `thenRn_`
298 mapFvRn rnConDecl condecls `thenRn` \ condecls' ->
299 lookupSysBinder gen_name1 `thenRn` \ name1' ->
300 lookupSysBinder gen_name2 `thenRn` \ name2' ->
301 rnDerivs derivings `thenRn` \ derivings' ->
302 returnRn (TyData new_or_data context' tycon' tyvars' condecls' nconstrs
303 derivings' src_loc name1' name2')
305 data_doc = text "the data type declaration for" <+> quotes (ppr tycon)
306 con_names = map conDeclName condecls
308 rnTyClDecl (TySynonym name tyvars ty src_loc)
309 = pushSrcLocRn src_loc $
310 doptRn Opt_GlasgowExts `thenRn` \ glaExts ->
311 lookupTopBndrRn name `thenRn` \ name' ->
312 bindTyVarsRn syn_doc tyvars $ \ tyvars' ->
313 rnHsType syn_doc (unquantify glaExts ty) `thenRn` \ ty' ->
314 returnRn (TySynonym name' tyvars' ty' src_loc)
316 syn_doc = text "the declaration for type synonym" <+> quotes (ppr name)
318 -- For H98 we do *not* universally quantify on the RHS of a synonym
319 -- Silently discard context... but the tyvars in the rest won't be in scope
320 unquantify glaExts (HsForAllTy Nothing ctxt ty) | glaExts = ty
321 unquantify glaExys ty = ty
323 rnTyClDecl (ClassDecl context cname tyvars fds sigs mbinds names src_loc)
324 = pushSrcLocRn src_loc $
326 lookupTopBndrRn cname `thenRn` \ cname' ->
328 -- Deal with the implicit tycon and datacon name
329 -- They aren't in scope (because they aren't visible to the user)
330 -- and what we want to do is simply look them up in the cache;
331 -- we jolly well ought to get a 'hit' there!
332 mapRn lookupSysBinder names `thenRn` \ names' ->
334 -- Tyvars scope over bindings and context
335 bindTyVars2Rn cls_doc tyvars $ \ clas_tyvar_names tyvars' ->
337 -- Check the superclasses
338 rnContext cls_doc context `thenRn` \ context' ->
340 -- Check the functional dependencies
341 rnFds cls_doc fds `thenRn` \ fds' ->
343 -- Check the signatures
344 -- First process the class op sigs (op_sigs), then the fixity sigs (non_op_sigs).
346 (op_sigs, non_op_sigs) = partition isClassOpSig sigs
347 sig_rdr_names_w_locs = [(op,locn) | ClassOpSig op _ _ locn <- sigs]
349 checkDupOrQualNames sig_doc sig_rdr_names_w_locs `thenRn_`
350 mapRn (rnClassOp cname' clas_tyvar_names fds') op_sigs `thenRn` \ sigs' ->
352 binders = mkNameSet [ nm | (ClassOpSig nm _ _ _) <- sigs' ]
354 renameSigs (okClsDclSig binders) non_op_sigs `thenRn` \ non_ops' ->
356 -- Typechecker is responsible for checking that we only
357 -- give default-method bindings for things in this class.
358 -- The renamer *could* check this for class decls, but can't
359 -- for instance decls.
361 returnRn (ClassDecl context' cname' tyvars' fds' (non_ops' ++ sigs') mbinds' names' src_loc)
363 cls_doc = text "the declaration for class" <+> ppr cname
364 sig_doc = text "the signatures for class" <+> ppr cname
365 meth_doc = text "the default-methods for class" <+> ppr cname
367 rnClassOp clas clas_tyvars clas_fds sig@(ClassOpSig op maybe_dm_stuff ty locn)
368 = pushSrcLocRn locn $
369 lookupTopBndrRn op `thenRn` \ op_name ->
371 -- Check the signature
372 rnHsSigType (quotes (ppr op)) ty `thenRn` \ new_ty ->
374 -- Make the default-method name
375 (case maybe_dm_stuff of
376 Nothing -> returnRn Nothing -- Source-file class decl
378 Just (DefMeth dm_rdr_name)
379 -> -- Imported class that has a default method decl
380 -- See comments with tname, snames, above
381 lookupSysBinder dm_rdr_name `thenRn` \ dm_name ->
382 returnRn (Just (DefMeth dm_name))
383 -- An imported class decl for a class decl that had an explicit default
384 -- method, mentions, rather than defines,
385 -- the default method, so we must arrange to pull it in
387 Just GenDefMeth -> returnRn (Just GenDefMeth)
388 Just NoDefMeth -> returnRn (Just NoDefMeth)
389 ) `thenRn` \ maybe_dm_stuff' ->
391 returnRn (ClassOpSig op_name maybe_dm_stuff' new_ty locn)
393 rnClassBinds :: RdrNameTyClDecl -> RenamedTyClDecl -> RnMS (RenamedTyClDecl, FreeVars)
394 -- Rename the mbinds only; the rest is done already
395 rnClassBinds (ClassDecl _ _ _ _ _ mbinds _ _ ) -- Get mbinds from here
396 (ClassDecl context cname tyvars fds sigs _ names src_loc) -- Everything else is here
397 = -- The newLocals call is tiresome: given a generic class decl
400 -- op {| x+y |} (Inl a) = ...
401 -- op {| x+y |} (Inr b) = ...
402 -- op {| a*b |} (a*b) = ...
403 -- we want to name both "x" tyvars with the same unique, so that they are
404 -- easy to group together in the typechecker.
406 extendTyVarEnvFVRn (map hsTyVarName tyvars) $
407 getLocalNameEnv `thenRn` \ name_env ->
409 meth_rdr_names_w_locs = collectLocatedMonoBinders mbinds
410 gen_rdr_tyvars_w_locs = [(tv,src_loc) | tv <- extractGenericPatTyVars mbinds,
411 not (tv `elemRdrEnv` name_env)]
413 checkDupOrQualNames meth_doc meth_rdr_names_w_locs `thenRn_`
414 newLocalsRn mkLocalName gen_rdr_tyvars_w_locs `thenRn` \ gen_tyvars ->
415 rnMethodBinds gen_tyvars mbinds `thenRn` \ (mbinds', meth_fvs) ->
416 returnRn (ClassDecl context cname tyvars fds sigs mbinds' names src_loc, meth_fvs)
420 %*********************************************************
422 \subsection{Support code for type/data declarations}
424 %*********************************************************
427 rnDerivs :: Maybe [RdrName] -> RnMS (Maybe [Name], FreeVars)
429 rnDerivs Nothing -- derivs not specified
430 = returnRn (Nothing, emptyFVs)
433 = mapRn do_one clss `thenRn` \ clss' ->
434 returnRn (Just clss', mkNameSet clss')
436 do_one cls = lookupOccRn cls `thenRn` \ clas_name ->
437 checkRn (getUnique clas_name `elem` derivableClassKeys)
438 (derivingNonStdClassErr clas_name) `thenRn_`
443 conDeclName :: RdrNameConDecl -> (RdrName, SrcLoc)
444 conDeclName (ConDecl n _ _ _ _ l) = (n,l)
446 rnConDecl :: RdrNameConDecl -> RnMS RenamedConDecl
447 rnConDecl (ConDecl name wkr tvs cxt details locn)
448 = pushSrcLocRn locn $
449 checkConName name `thenRn_`
450 lookupTopBndrRn name `thenRn` \ new_name ->
452 lookupSysBinder wkr `thenRn` \ new_wkr ->
453 -- See comments with ClassDecl
455 bindTyVarsRn doc tvs $ \ new_tyvars ->
456 rnContext doc cxt `thenRn` \ new_context ->
457 rnConDetails doc locn details `thenRn` \ new_details ->
458 returnRn (ConDecl new_name new_wkr new_tyvars new_context new_details locn)
460 doc = text "the definition of data constructor" <+> quotes (ppr name)
462 rnConDetails doc locn (VanillaCon tys)
463 = mapRn (rnBangTy doc) tys `thenRn` \ new_tys ->
464 returnRn (VanillaCon new_tys)
466 rnConDetails doc locn (InfixCon ty1 ty2)
467 = rnBangTy doc ty1 `thenRn` \ new_ty1 ->
468 rnBangTy doc ty2 `thenRn` \ new_ty2 ->
469 returnRn (InfixCon new_ty1 new_ty2)
471 rnConDetails doc locn (RecCon fields)
472 = checkDupOrQualNames doc field_names `thenRn_`
473 mapRn (rnField doc) fields `thenRn` \ new_fields ->
474 returnRn (RecCon new_fields)
476 field_names = [(fld, locn) | (flds, _) <- fields, fld <- flds]
478 rnField doc (names, ty)
479 = mapRn lookupTopBndrRn names `thenRn` \ new_names ->
480 rnBangTy doc ty `thenRn` \ new_ty ->
481 returnRn (new_names, new_ty)
483 rnBangTy doc (Banged ty)
484 = rnHsType doc ty `thenRn` \ new_ty ->
485 returnRn (Banged new_ty)
487 rnBangTy doc (Unbanged ty)
488 = rnHsType doc ty `thenRn` \ new_ty ->
489 returnRn (Unbanged new_ty)
491 rnBangTy doc (Unpacked ty)
492 = rnHsType doc ty `thenRn` \ new_ty ->
493 returnRn (Unpacked new_ty)
495 -- This data decl will parse OK
497 -- treating "a" as the constructor.
498 -- It is really hard to make the parser spot this malformation.
499 -- So the renamer has to check that the constructor is legal
501 -- We can get an operator as the constructor, even in the prefix form:
502 -- data T = :% Int Int
503 -- from interface files, which always print in prefix form
506 = checkRn (isRdrDataCon name)
511 %*********************************************************
513 \subsection{Support code to rename types}
515 %*********************************************************
518 rnHsTypeFVs :: SDoc -> RdrNameHsType -> RnMS (RenamedHsType, FreeVars)
519 rnHsTypeFVs doc_str ty
520 = rnHsType doc_str ty `thenRn` \ ty' ->
521 returnRn (ty', extractHsTyNames ty')
523 rnHsSigTypeFVs :: SDoc -> RdrNameHsType -> RnMS (RenamedHsType, FreeVars)
524 rnHsSigTypeFVs doc_str ty
525 = rnHsSigType doc_str ty `thenRn` \ ty' ->
526 returnRn (ty', extractHsTyNames ty')
528 rnHsSigType :: SDoc -> RdrNameHsType -> RnMS RenamedHsType
529 -- rnHsSigType is used for source-language type signatures,
530 -- which use *implicit* universal quantification.
531 rnHsSigType doc_str ty
532 = rnHsType (text "the type signature for" <+> doc_str) ty
534 ---------------------------------------
535 rnHsType :: SDoc -> RdrNameHsType -> RnMS RenamedHsType
537 rnHsType doc (HsForAllTy Nothing ctxt ty)
538 -- Implicit quantifiction in source code (no kinds on tyvars)
539 -- Given the signature C => T we universally quantify
540 -- over FV(T) \ {in-scope-tyvars}
541 = getLocalNameEnv `thenRn` \ name_env ->
543 mentioned_in_tau = extractHsTyRdrTyVars ty
544 mentioned_in_ctxt = extractHsCtxtRdrTyVars ctxt
545 mentioned = nub (mentioned_in_tau ++ mentioned_in_ctxt)
546 forall_tyvars = filter (not . (`elemRdrEnv` name_env)) mentioned
548 rnForAll doc (map UserTyVar forall_tyvars) ctxt ty
550 rnHsType doc (HsForAllTy (Just forall_tyvars) ctxt tau)
551 -- Explicit quantification.
552 -- Check that the forall'd tyvars are actually
553 -- mentioned in the type, and produce a warning if not
555 mentioned_in_tau = extractHsTyRdrTyVars tau
556 mentioned_in_ctxt = extractHsCtxtRdrTyVars ctxt
557 mentioned = nub (mentioned_in_tau ++ mentioned_in_ctxt)
558 forall_tyvar_names = hsTyVarNames forall_tyvars
560 -- Explicitly quantified but not mentioned in ctxt or tau
561 warn_guys = filter (`notElem` mentioned) forall_tyvar_names
563 mapRn_ (forAllWarn doc tau) warn_guys `thenRn_`
564 rnForAll doc forall_tyvars ctxt tau
566 rnHsType doc (HsTyVar tyvar)
567 = lookupOccRn tyvar `thenRn` \ tyvar' ->
568 returnRn (HsTyVar tyvar')
570 rnHsType doc (HsOpTy ty1 opname ty2)
571 = lookupOccRn opname `thenRn` \ name' ->
572 rnHsType doc ty1 `thenRn` \ ty1' ->
573 rnHsType doc ty2 `thenRn` \ ty2' ->
574 returnRn (HsOpTy ty1' name' ty2')
576 rnHsType doc (HsNumTy i)
577 | i == 1 = returnRn (HsNumTy i)
578 | otherwise = failWithRn (HsNumTy i)
579 (ptext SLIT("Only unit numeric type pattern is valid"))
581 rnHsType doc (HsFunTy ty1 ty2)
582 = rnHsType doc ty1 `thenRn` \ ty1' ->
583 -- Might find a for-all as the arg of a function type
584 rnHsType doc ty2 `thenRn` \ ty2' ->
585 -- Or as the result. This happens when reading Prelude.hi
586 -- when we find return :: forall m. Monad m -> forall a. a -> m a
587 returnRn (HsFunTy ty1' ty2')
589 rnHsType doc (HsListTy ty)
590 = rnHsType doc ty `thenRn` \ ty' ->
591 returnRn (HsListTy ty')
593 -- Unboxed tuples are allowed to have poly-typed arguments. These
594 -- sometimes crop up as a result of CPR worker-wrappering dictionaries.
595 rnHsType doc (HsTupleTy (HsTupCon _ boxity) tys)
596 -- Don't do lookupOccRn, because this is built-in syntax
597 -- so it doesn't need to be in scope
598 = mapFvRn (rnHsType doc) tys `thenRn` \ tys' ->
599 returnRn (HsTupleTy (HsTupCon n' boxity) tys')
601 n' = tupleTyCon_name boxity (length tys)
604 rnHsType doc (HsAppTy ty1 ty2)
605 = rnHsType doc ty1 `thenRn` \ ty1' ->
606 rnHsType doc ty2 `thenRn` \ ty2' ->
607 returnRn (HsAppTy ty1' ty2')
609 rnHsType doc (HsPredTy pred)
610 = rnPred doc pred `thenRn` \ pred' ->
611 returnRn (HsPredTy pred')
613 rnHsType doc (HsUsgForAllTy uv_rdr ty)
614 = bindUVarRn doc uv_rdr $ \ uv_name ->
615 rnHsType doc ty `thenRn` \ ty' ->
616 returnRn (HsUsgForAllTy uv_name ty')
618 rnHsType doc (HsUsgTy usg ty)
619 = newUsg usg `thenRn` \ usg' ->
620 rnHsType doc ty `thenRn` \ ty' ->
621 -- A for-all can occur inside a usage annotation
622 returnRn (HsUsgTy usg' ty')
624 newUsg usg = case usg of
625 HsUsOnce -> returnRn HsUsOnce
626 HsUsMany -> returnRn HsUsMany
627 HsUsVar uv_rdr -> lookupOccRn uv_rdr `thenRn` \ uv_name ->
628 returnRn (HsUsVar uv_name)
630 rnHsTypes doc tys = mapRn (rnHsType doc) tys
634 -- We use lookupOcc here because this is interface file only stuff
635 -- and we need the workers...
636 rnHsTupCon (HsTupCon n boxity)
637 = lookupOccRn n `thenRn` \ n' ->
638 returnRn (HsTupCon n' boxity)
640 rnHsTupConWkr (HsTupCon n boxity)
641 -- Tuple construtors are for the *worker* of the tuple
642 -- Going direct saves needless messing about
643 = lookupOccRn (mkRdrNameWkr n) `thenRn` \ n' ->
644 returnRn (HsTupCon n' boxity)
648 rnForAll doc forall_tyvars ctxt ty
649 = bindTyVarsFVRn doc forall_tyvars $ \ new_tyvars ->
650 rnContext doc ctxt `thenRn` \ new_ctxt ->
651 rnHsType doc ty `thenRn` \ new_ty ->
652 returnRn (mkHsForAllTy (Just new_tyvars) new_ctxt new_ty)
656 rnContext :: SDoc -> RdrNameContext -> RnMS RenamedContext
658 = mapRn rn_pred ctxt `thenRn` \ theta ->
660 (_, dups) = removeDupsEq theta
661 -- We only have equality, not ordering
663 -- Check for duplicate assertions
664 -- If this isn't an error, then it ought to be:
665 mapRn (addWarnRn . dupClassAssertWarn theta) dups `thenRn_`
668 --Someone discovered that @CCallable@ and @CReturnable@
669 -- could be used in contexts such as:
670 -- foo :: CCallable a => a -> PrimIO Int
671 -- Doing this utterly wrecks the whole point of introducing these
672 -- classes so we specifically check that this isn't being done.
673 rn_pred pred = rnPred doc pred `thenRn` \ pred'->
674 checkRn (not (bad_pred pred'))
675 (naughtyCCallContextErr pred') `thenRn_`
678 bad_pred (HsPClass clas _) = getUnique clas `elem` cCallishClassKeys
679 bad_pred other = False
682 rnPred doc (HsPClass clas tys)
683 = lookupOccRn clas `thenRn` \ clas_name ->
684 rnHsTypes doc tys `thenRn` \ tys' ->
685 returnRn (HsPClass clas_name tys')
687 rnPred doc (HsPIParam n ty)
688 = newIPName n `thenRn` \ name ->
689 rnHsType doc ty `thenRn` \ ty' ->
690 returnRn (HsPIParam name ty')
694 rnFds :: SDoc -> [FunDep RdrName] -> RnMS ([FunDep Name], FreeVars)
697 = mapAndUnzipRn rn_fds fds `thenRn` \ (theta, fvs_s) ->
698 returnRn (theta, plusFVs fvs_s)
701 = rnHsTyVars doc tys1 `thenRn` \ (tys1', fvs1) ->
702 rnHsTyVars doc tys2 `thenRn` \ (tys2', fvs2) ->
703 returnRn ((tys1', tys2'), fvs1 `plusFV` fvs2)
705 rnHsTyVars doc tvs = mapFvRn (rnHsTyvar doc) tvs
707 = lookupOccRn tyvar `thenRn` \ tyvar' ->
708 returnRn (tyvar', unitFV 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 bindCoreLocalFVRn 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 bindCoreLocalFVRn name ( \ name' ->
797 thing_inside (UfValBinder name' ty')
798 ) `thenRn` \ (result, fvs2) ->
799 returnRn (result, fvs1 `plusFV` fvs2)
801 doc = text "unfolding id"
803 rnCoreBndr (UfTyBinder name kind) thing_inside
804 = bindCoreLocalRn name $ \ name' ->
805 thing_inside (UfTyBinder name' kind)
807 rnCoreBndrs [] thing_inside = thing_inside []
808 rnCoreBndrs (b:bs) thing_inside = rnCoreBndr b $ \ name' ->
809 rnCoreBndrs bs $ \ names' ->
810 thing_inside (name':names')
814 rnCoreAlt (con, bndrs, rhs)
815 = rnUfCon con bndrs `thenRn` \ con' ->
816 bindCoreLocalsRn bndrs $ \ bndrs' ->
817 rnCoreExpr rhs `thenRn` \ rhs' ->
818 returnRn (con', bndrs', rhs')
821 = rnHsType (text "unfolding coerce") ty `thenRn` \ ty' ->
822 returnRn (UfCoerce ty')
824 rnNote (UfSCC cc) = returnRn (UfSCC cc)
825 rnNote UfInlineCall = returnRn UfInlineCall
826 rnNote UfInlineMe = returnRn UfInlineMe
832 rnUfCon (UfTupleAlt tup_con) bndrs
833 = rnHsTupCon tup_con `thenRn` \ (HsTupCon con' _) ->
834 returnRn (UfDataAlt con')
835 -- Makes the type checker a little easier
837 rnUfCon (UfDataAlt con) _
838 = lookupOccRn con `thenRn` \ con' ->
839 returnRn (UfDataAlt con')
841 rnUfCon (UfLitAlt lit) _
842 = returnRn (UfLitAlt lit)
844 rnUfCon (UfLitLitAlt lit ty) _
845 = rnHsType (text "litlit") ty `thenRn` \ ty' ->
846 returnRn (UfLitLitAlt lit ty')
849 %*********************************************************
851 \subsection{Rule shapes}
853 %*********************************************************
855 Check the shape of a transformation rule LHS. Currently
856 we only allow LHSs of the form @(f e1 .. en)@, where @f@ is
857 not one of the @forall@'d variables.
860 validRuleLhs foralls lhs
863 check (HsApp e1 e2) = check e1
864 check (HsVar v) | v `notElem` foralls = True
869 %*********************************************************
873 %*********************************************************
876 derivingNonStdClassErr clas
877 = hsep [ptext SLIT("non-standard class"), ppr clas, ptext SLIT("in deriving clause")]
880 = hsep [ptext SLIT("Illegal data constructor name"), quotes (ppr name)]
882 forAllWarn doc ty tyvar
883 = doptRn Opt_WarnUnusedMatches `thenRn` \ warn_unused -> case () of
884 () | not warn_unused -> returnRn ()
886 -> getModeRn `thenRn` \ mode ->
889 InterfaceMode -> returnRn () ; -- Don't warn of unused tyvars in interface files
890 -- unless DEBUG is on, in which case it is slightly
891 -- informative. They can arise from mkRhsTyLam,
892 #endif -- leading to (say) f :: forall a b. [b] -> [b]
895 sep [ptext SLIT("The universally quantified type variable") <+> quotes (ppr tyvar),
896 nest 4 (ptext SLIT("does not appear in the type") <+> quotes (ppr ty))]
898 (ptext SLIT("In") <+> doc)
902 badRuleLhsErr name lhs
903 = sep [ptext SLIT("Rule") <+> ptext name <> colon,
904 nest 4 (ptext SLIT("Illegal left-hand side:") <+> ppr lhs)]
906 ptext SLIT("LHS must be of form (f e1 .. en) where f is not forall'd")
909 = sep [ptext SLIT("Rule") <+> ptext name <> colon,
910 ptext SLIT("Forall'd variable") <+> quotes (ppr var) <+>
911 ptext SLIT("does not appear on left hand side")]
913 badExtName :: ExtName -> Message
915 = sep [quotes (ppr ext_nm) <+> ptext SLIT("is not a valid C identifier")]
917 dupClassAssertWarn ctxt (assertion : dups)
918 = sep [hsep [ptext SLIT("Duplicate class assertion"),
919 quotes (ppr assertion),
920 ptext SLIT("in the context:")],
921 nest 4 (pprHsContext ctxt <+> ptext SLIT("..."))]
923 naughtyCCallContextErr (HsPClass clas _)
924 = sep [ptext SLIT("Can't use class") <+> quotes (ppr clas),
925 ptext SLIT("in a context")]