2 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
4 \section[RnSource]{Main pass of renamer}
7 module RnSource ( rnDecl, rnSourceDecls, rnHsType, rnHsSigType ) where
9 #include "HsVersions.h"
14 import HsTypes ( hsTyVarNames, pprHsContext )
15 import RdrName ( RdrName, isRdrDataCon, rdrNameOcc, isRdrTyVar, mkRdrNameWkr )
16 import RdrHsSyn ( RdrNameContext, RdrNameHsType, RdrNameConDecl,
17 extractRuleBndrsTyVars, extractHsTyRdrTyVars,
18 extractHsTysRdrTyVars, extractHsCtxtRdrTyVars
23 import RnBinds ( rnTopBinds, rnMethodBinds, renameSigs, unknownSigErr )
24 import RnEnv ( bindTyVarsRn, lookupTopBndrRn, lookupOccRn, newIPName,
25 lookupOrigName, lookupOrigNames, lookupSysBinder,
26 bindLocalsRn, bindLocalRn, bindLocalsFVRn, bindUVarRn,
27 bindTyVarsFVRn, bindTyVarsFV2Rn, extendTyVarEnvFVRn,
28 bindCoreLocalFVRn, bindCoreLocalsFVRn, bindLocalNames,
29 checkDupOrQualNames, checkDupNames,
30 FreeVars, emptyFVs, plusFV, plusFVs, unitFV,
35 import FunDeps ( oclose )
36 import Class ( FunDep )
38 import Name ( Name, OccName,
39 ExportFlag(..), Provenance(..),
40 nameOccName, NamedThing(..)
43 import FiniteMap ( elemFM )
44 import PrelInfo ( derivableClassKeys, cCallishClassKeys,
45 deRefStablePtr_RDR, makeStablePtr_RDR,
46 bindIO_RDR, returnIO_RDR
48 import Bag ( bagToList )
49 import List ( partition, nub )
51 import SrcLoc ( SrcLoc )
52 import CmdLineOpts ( opt_GlasgowExts, opt_WarnUnusedMatches ) -- Warn of unused for-all'd tyvars
53 import Unique ( Uniquable(..) )
54 import ErrUtils ( Message )
55 import CStrings ( isCLabelString )
59 @rnDecl@ `renames' declarations.
60 It simultaneously performs dependency analysis and precedence parsing.
61 It also does the following error checks:
64 Checks that tyvars are used properly. This includes checking
65 for undefined tyvars, and tyvars in contexts that are ambiguous.
66 (Some of this checking has now been moved to module @TcMonoType@,
67 since we don't have functional dependency information at this point.)
69 Checks that all variable occurences are defined.
71 Checks the @(..)@ etc constraints in the export list.
75 %*********************************************************
77 \subsection{Value declarations}
79 %*********************************************************
82 rnSourceDecls :: [RdrNameHsDecl] -> RnMS ([RenamedHsDecl], FreeVars)
83 -- The decls get reversed, but that's ok
86 = go emptyFVs [] decls
88 -- Fixity and deprecations have been dealt with already; ignore them
89 go fvs ds' [] = returnRn (ds', fvs)
90 go fvs ds' (FixD _:ds) = go fvs ds' ds
91 go fvs ds' (DeprecD _:ds) = go fvs ds' ds
92 go fvs ds' (d:ds) = rnDecl d `thenRn` \(d', fvs') ->
93 go (fvs `plusFV` fvs') (d':ds') ds
97 %*********************************************************
99 \subsection{Value declarations}
101 %*********************************************************
104 -- rnDecl does all the work
105 rnDecl :: RdrNameHsDecl -> RnMS (RenamedHsDecl, FreeVars)
107 rnDecl (ValD binds) = rnTopBinds binds `thenRn` \ (new_binds, fvs) ->
108 returnRn (ValD new_binds, fvs)
111 rnDecl (SigD (IfaceSig name ty id_infos loc))
113 lookupTopBndrRn name `thenRn` \ name' ->
114 rnHsType doc_str ty `thenRn` \ (ty',fvs1) ->
115 mapFvRn rnIdInfo id_infos `thenRn` \ (id_infos', fvs2) ->
116 returnRn (SigD (IfaceSig name' ty' id_infos' loc), fvs1 `plusFV` fvs2)
118 doc_str = text "the interface signature for" <+> quotes (ppr name)
121 %*********************************************************
123 \subsection{Type declarations}
125 %*********************************************************
127 @rnTyDecl@ uses the `global name function' to create a new type
128 declaration in which local names have been replaced by their original
129 names, reporting any unknown names.
131 Renaming type variables is a pain. Because they now contain uniques,
132 it is necessary to pass in an association list which maps a parsed
133 tyvar to its @Name@ representation.
134 In some cases (type signatures of values),
135 it is even necessary to go over the type first
136 in order to get the set of tyvars used by it, make an assoc list,
137 and then go over it again to rename the tyvars!
138 However, we can also do some scoping checks at the same time.
141 rnDecl (TyClD (TyData new_or_data context tycon tyvars condecls nconstrs derivings pragmas src_loc))
142 = pushSrcLocRn src_loc $
143 lookupTopBndrRn tycon `thenRn` \ tycon' ->
144 bindTyVarsFVRn data_doc tyvars $ \ tyvars' ->
145 rnContext data_doc context `thenRn` \ (context', cxt_fvs) ->
146 checkDupOrQualNames data_doc con_names `thenRn_`
147 mapFvRn rnConDecl condecls `thenRn` \ (condecls', con_fvs) ->
148 rnDerivs derivings `thenRn` \ (derivings', deriv_fvs) ->
149 ASSERT(isNoDataPragmas pragmas)
150 returnRn (TyClD (TyData new_or_data context' tycon' tyvars' condecls' nconstrs
151 derivings' noDataPragmas src_loc),
152 cxt_fvs `plusFV` con_fvs `plusFV` deriv_fvs)
154 data_doc = text "the data type declaration for" <+> quotes (ppr tycon)
155 con_names = map conDeclName condecls
157 rnDecl (TyClD (TySynonym name tyvars ty src_loc))
158 = pushSrcLocRn src_loc $
159 lookupTopBndrRn name `thenRn` \ name' ->
160 bindTyVarsFVRn syn_doc tyvars $ \ tyvars' ->
161 rnHsType syn_doc (unquantify ty) `thenRn` \ (ty', ty_fvs) ->
162 returnRn (TyClD (TySynonym name' tyvars' ty' src_loc), ty_fvs)
164 syn_doc = text "the declaration for type synonym" <+> quotes (ppr name)
166 -- For H98 we do *not* universally quantify on the RHS of a synonym
167 -- Silently discard context... but the tyvars in the rest won't be in scope
168 unquantify (HsForAllTy Nothing ctxt ty) | not opt_GlasgowExts = ty
171 rnDecl (TyClD (ClassDecl context cname tyvars fds sigs mbinds pragmas
172 tname dname dwname snames src_loc))
173 = pushSrcLocRn src_loc $
175 lookupTopBndrRn cname `thenRn` \ cname' ->
177 -- Deal with the implicit tycon and datacon name
178 -- They aren't in scope (because they aren't visible to the user)
179 -- and what we want to do is simply look them up in the cache;
180 -- we jolly well ought to get a 'hit' there!
181 -- So the 'Imported' part of this call is not relevant.
182 -- Unclean; but since these two are the only place this happens
183 -- I can't work up the energy to do it more beautifully
184 lookupSysBinder tname `thenRn` \ tname' ->
185 lookupSysBinder dname `thenRn` \ dname' ->
186 lookupSysBinder dwname `thenRn` \ dwname' ->
187 mapRn lookupSysBinder snames `thenRn` \ snames' ->
189 -- Tyvars scope over bindings and context
190 bindTyVarsFV2Rn cls_doc tyvars ( \ clas_tyvar_names tyvars' ->
192 -- Check the superclasses
193 rnContext cls_doc context `thenRn` \ (context', cxt_fvs) ->
195 -- Check the functional dependencies
196 rnFds cls_doc fds `thenRn` \ (fds', fds_fvs) ->
198 -- Check the signatures
200 -- First process the class op sigs, then the fixity sigs.
201 (op_sigs, non_op_sigs) = partition isClassOpSig sigs
203 checkDupOrQualNames sig_doc sig_rdr_names_w_locs `thenRn_`
204 mapFvRn (rn_op cname' clas_tyvar_names fds') op_sigs `thenRn` \ (sigs', sig_fvs) ->
206 binders = mkNameSet [ nm | (ClassOpSig nm _ _ _) <- sigs' ]
208 renameSigs (okClsDclSig binders) non_op_sigs `thenRn` \ (non_ops', fix_fvs) ->
211 checkDupOrQualNames meth_doc meth_rdr_names_w_locs `thenRn_`
212 rnMethodBinds mbinds `thenRn` \ (mbinds', meth_fvs) ->
214 -- Typechecker is responsible for checking that we only
215 -- give default-method bindings for things in this class.
216 -- The renamer *could* check this for class decls, but can't
217 -- for instance decls.
219 ASSERT(isNoClassPragmas pragmas)
220 returnRn (TyClD (ClassDecl context' cname' tyvars' fds' (non_ops' ++ sigs') mbinds'
221 NoClassPragmas tname' dname' dwname' snames' src_loc),
230 cls_doc = text "the declaration for class" <+> ppr cname
231 sig_doc = text "the signatures for class" <+> ppr cname
232 meth_doc = text "the default-methods for class" <+> ppr cname
234 sig_rdr_names_w_locs = [(op,locn) | ClassOpSig op _ _ locn <- sigs]
235 meth_rdr_names_w_locs = bagToList (collectMonoBinders mbinds)
237 rn_op clas clas_tyvars clas_fds sig@(ClassOpSig op maybe_dm_stuff ty locn)
238 = pushSrcLocRn locn $
239 lookupTopBndrRn op `thenRn` \ op_name ->
241 -- Check the signature
242 rnHsSigType (quotes (ppr op)) ty `thenRn` \ (new_ty, op_ty_fvs) ->
244 check_in_op_ty clas_tyvar =
245 checkRn (clas_tyvar `elemNameSet` oclose clas_fds op_ty_fvs)
246 (classTyVarNotInOpTyErr clas_tyvar sig)
248 mapRn_ check_in_op_ty clas_tyvars `thenRn_`
250 -- Make the default-method name
251 (case maybe_dm_stuff of
252 Nothing -> returnRn (Nothing, emptyFVs) -- Source-file class decl
254 Just (dm_rdr_name, explicit_dm)
255 -> -- Imported class that has a default method decl
256 -- See comments with tname, snames, above
257 lookupSysBinder dm_rdr_name `thenRn` \ dm_name ->
258 returnRn (Just (dm_name, explicit_dm),
259 if explicit_dm then unitFV dm_name else emptyFVs)
260 -- An imported class decl for a class decl that had an explicit default
261 -- method, mentions, rather than defines,
262 -- the default method, so we must arrange to pull it in
263 ) `thenRn` \ (maybe_dm_stuff', dm_fvs) ->
265 returnRn (ClassOpSig op_name maybe_dm_stuff' new_ty locn, op_ty_fvs `plusFV` dm_fvs)
269 %*********************************************************
271 \subsection{Instance declarations}
273 %*********************************************************
276 rnDecl (InstD (InstDecl inst_ty mbinds uprags maybe_dfun_rdr_name src_loc))
277 = pushSrcLocRn src_loc $
278 rnHsSigType (text "an instance decl") inst_ty `thenRn` \ (inst_ty', inst_fvs) ->
280 inst_tyvars = case inst_ty' of
281 HsForAllTy (Just inst_tyvars) _ _ -> inst_tyvars
283 -- (Slightly strangely) the forall-d tyvars scope over
284 -- the method bindings too
287 -- Rename the bindings
288 -- NB meth_names can be qualified!
289 checkDupNames meth_doc meth_names `thenRn_`
290 extendTyVarEnvFVRn inst_tyvars (
292 ) `thenRn` \ (mbinds', meth_fvs) ->
294 binders = map fst (bagToList (collectMonoBinders mbinds'))
295 binder_set = mkNameSet binders
297 -- Rename the prags and signatures.
298 -- Note that the type variables are not in scope here,
299 -- so that instance Eq a => Eq (T a) where
300 -- {-# SPECIALISE instance Eq a => Eq (T [a]) #-}
303 -- But the (unqualified) method names are in scope
304 bindLocalNames binders (
305 renameSigs (okInstDclSig binder_set) uprags
306 ) `thenRn` \ (new_uprags, prag_fvs) ->
308 (case maybe_dfun_rdr_name of
309 Nothing -> returnRn (Nothing, emptyFVs)
311 Just dfun_rdr_name -> lookupSysBinder dfun_rdr_name `thenRn` \ dfun_name ->
312 returnRn (Just dfun_name, unitFV dfun_name)
313 ) `thenRn` \ (maybe_dfun_name, dfun_fv) ->
315 -- The typechecker checks that all the bindings are for the right class.
316 returnRn (InstD (InstDecl inst_ty' mbinds' new_uprags maybe_dfun_name src_loc),
317 inst_fvs `plusFV` meth_fvs `plusFV` prag_fvs `plusFV` dfun_fv)
319 meth_doc = text "the bindings in an instance declaration"
320 meth_names = bagToList (collectMonoBinders mbinds)
323 %*********************************************************
325 \subsection{Default declarations}
327 %*********************************************************
330 rnDecl (DefD (DefaultDecl tys src_loc))
331 = pushSrcLocRn src_loc $
332 rnHsTypes doc_str tys `thenRn` \ (tys', fvs) ->
333 returnRn (DefD (DefaultDecl tys' src_loc), fvs)
335 doc_str = text "a `default' declaration"
338 %*********************************************************
340 \subsection{Foreign declarations}
342 %*********************************************************
345 rnDecl (ForD (ForeignDecl name imp_exp ty ext_nm cconv src_loc))
346 = pushSrcLocRn src_loc $
347 lookupOccRn name `thenRn` \ name' ->
350 | isDyn = lookupOrigNames [makeStablePtr_RDR, deRefStablePtr_RDR,
351 bindIO_RDR, returnIO_RDR]
353 lookupOrigNames [bindIO_RDR, returnIO_RDR] `thenRn` \ fvs ->
354 returnRn (addOneFV fvs name')
355 extra_fvs other = returnRn emptyFVs
357 checkRn (ok_ext_nm ext_nm) (badExtName ext_nm) `thenRn_`
359 extra_fvs imp_exp `thenRn` \ fvs1 ->
361 rnHsSigType fo_decl_msg ty `thenRn` \ (ty', fvs2) ->
362 returnRn (ForD (ForeignDecl name' imp_exp ty' ext_nm cconv src_loc),
365 fo_decl_msg = ptext SLIT("a foreign declaration")
366 isDyn = isDynamicExtName ext_nm
368 ok_ext_nm Dynamic = True
369 ok_ext_nm (ExtName nm (Just mb)) = isCLabelString nm && isCLabelString mb
370 ok_ext_nm (ExtName nm Nothing) = isCLabelString nm
373 %*********************************************************
377 %*********************************************************
380 rnDecl (RuleD (IfaceRule rule_name vars fn args rhs src_loc))
381 = pushSrcLocRn src_loc $
382 lookupOccRn fn `thenRn` \ fn' ->
383 rnCoreBndrs vars $ \ vars' ->
384 mapFvRn rnCoreExpr args `thenRn` \ (args', fvs1) ->
385 rnCoreExpr rhs `thenRn` \ (rhs', fvs2) ->
386 returnRn (RuleD (IfaceRule rule_name vars' fn' args' rhs' src_loc),
387 (fvs1 `plusFV` fvs2) `addOneFV` fn')
389 rnDecl (RuleD (IfaceRuleOut fn rule))
390 -- This one is used for BuiltInRules
391 -- The rule itself is already done, but the thing
392 -- to attach it to is not.
393 = lookupOccRn fn `thenRn` \ fn' ->
394 returnRn (RuleD (IfaceRuleOut fn' rule), unitFV fn')
396 rnDecl (RuleD (HsRule rule_name tvs vars lhs rhs src_loc))
398 pushSrcLocRn src_loc $
400 bindTyVarsFV2Rn doc (map UserTyVar sig_tvs) $ \ sig_tvs' _ ->
401 bindLocalsFVRn doc (map get_var vars) $ \ ids ->
402 mapFvRn rn_var (vars `zip` ids) `thenRn` \ (vars', fv_vars) ->
404 rnExpr lhs `thenRn` \ (lhs', fv_lhs) ->
405 rnExpr rhs `thenRn` \ (rhs', fv_rhs) ->
406 checkRn (validRuleLhs ids lhs')
407 (badRuleLhsErr rule_name lhs') `thenRn_`
409 bad_vars = [var | var <- ids, not (var `elemNameSet` fv_lhs)]
411 mapRn (addErrRn . badRuleVar rule_name) bad_vars `thenRn_`
412 returnRn (RuleD (HsRule rule_name sig_tvs' vars' lhs' rhs' src_loc),
413 fv_vars `plusFV` fv_lhs `plusFV` fv_rhs)
415 doc = text "the transformation rule" <+> ptext rule_name
416 sig_tvs = extractRuleBndrsTyVars vars
418 get_var (RuleBndr v) = v
419 get_var (RuleBndrSig v _) = v
421 rn_var (RuleBndr v, id) = returnRn (RuleBndr id, emptyFVs)
422 rn_var (RuleBndrSig v t, id) = rnHsType doc t `thenRn` \ (t', fvs) ->
423 returnRn (RuleBndrSig id t', fvs)
427 %*********************************************************
429 \subsection{Support code for type/data declarations}
431 %*********************************************************
434 rnDerivs :: Maybe [RdrName] -> RnMS (Maybe [Name], FreeVars)
436 rnDerivs Nothing -- derivs not specified
437 = returnRn (Nothing, emptyFVs)
440 = mapRn do_one clss `thenRn` \ clss' ->
441 returnRn (Just clss', mkNameSet clss')
443 do_one cls = lookupOccRn cls `thenRn` \ clas_name ->
444 checkRn (getUnique clas_name `elem` derivableClassKeys)
445 (derivingNonStdClassErr clas_name) `thenRn_`
450 conDeclName :: RdrNameConDecl -> (RdrName, SrcLoc)
451 conDeclName (ConDecl n _ _ _ _ l) = (n,l)
453 rnConDecl :: RdrNameConDecl -> RnMS (RenamedConDecl, FreeVars)
454 rnConDecl (ConDecl name wkr tvs cxt details locn)
455 = pushSrcLocRn locn $
456 checkConName name `thenRn_`
457 lookupTopBndrRn name `thenRn` \ new_name ->
459 lookupSysBinder wkr `thenRn` \ new_wkr ->
460 -- See comments with ClassDecl
462 bindTyVarsFVRn doc tvs $ \ new_tyvars ->
463 rnContext doc cxt `thenRn` \ (new_context, cxt_fvs) ->
464 rnConDetails doc locn details `thenRn` \ (new_details, det_fvs) ->
465 returnRn (ConDecl new_name new_wkr new_tyvars new_context new_details locn,
466 cxt_fvs `plusFV` det_fvs)
468 doc = text "the definition of data constructor" <+> quotes (ppr name)
470 rnConDetails doc locn (VanillaCon tys)
471 = mapFvRn (rnBangTy doc) tys `thenRn` \ (new_tys, fvs) ->
472 returnRn (VanillaCon new_tys, fvs)
474 rnConDetails doc locn (InfixCon ty1 ty2)
475 = rnBangTy doc ty1 `thenRn` \ (new_ty1, fvs1) ->
476 rnBangTy doc ty2 `thenRn` \ (new_ty2, fvs2) ->
477 returnRn (InfixCon new_ty1 new_ty2, fvs1 `plusFV` fvs2)
479 rnConDetails doc locn (RecCon fields)
480 = checkDupOrQualNames doc field_names `thenRn_`
481 mapFvRn (rnField doc) fields `thenRn` \ (new_fields, fvs) ->
482 returnRn (RecCon new_fields, fvs)
484 field_names = [(fld, locn) | (flds, _) <- fields, fld <- flds]
486 rnField doc (names, ty)
487 = mapRn lookupTopBndrRn names `thenRn` \ new_names ->
488 rnBangTy doc ty `thenRn` \ (new_ty, fvs) ->
489 returnRn ((new_names, new_ty), fvs)
491 rnBangTy doc (Banged ty)
492 = rnHsType doc ty `thenRn` \ (new_ty, fvs) ->
493 returnRn (Banged new_ty, fvs)
495 rnBangTy doc (Unbanged ty)
496 = rnHsType doc ty `thenRn` \ (new_ty, fvs) ->
497 returnRn (Unbanged new_ty, fvs)
499 rnBangTy doc (Unpacked ty)
500 = rnHsType doc ty `thenRn` \ (new_ty, fvs) ->
501 returnRn (Unpacked new_ty, fvs)
503 -- This data decl will parse OK
505 -- treating "a" as the constructor.
506 -- It is really hard to make the parser spot this malformation.
507 -- So the renamer has to check that the constructor is legal
509 -- We can get an operator as the constructor, even in the prefix form:
510 -- data T = :% Int Int
511 -- from interface files, which always print in prefix form
514 = checkRn (isRdrDataCon name)
519 %*********************************************************
521 \subsection{Support code to rename types}
523 %*********************************************************
526 rnHsSigType :: SDoc -> RdrNameHsType -> RnMS (RenamedHsType, FreeVars)
527 -- rnHsSigType is used for source-language type signatures,
528 -- which use *implicit* universal quantification.
529 rnHsSigType doc_str ty
530 = rnHsType (text "the type signature for" <+> doc_str) ty
532 ---------------------------------------
533 rnHsType :: SDoc -> RdrNameHsType -> RnMS (RenamedHsType, FreeVars)
535 rnHsType doc (HsForAllTy Nothing ctxt ty)
536 -- Implicit quantifiction in source code (no kinds on tyvars)
537 -- Given the signature C => T we universally quantify
538 -- over FV(T) \ {in-scope-tyvars}
539 = getLocalNameEnv `thenRn` \ name_env ->
541 mentioned_in_tau = extractHsTyRdrTyVars ty
542 mentioned_in_ctxt = extractHsCtxtRdrTyVars ctxt
543 mentioned = nub (mentioned_in_tau ++ mentioned_in_ctxt)
544 forall_tyvars = filter (not . (`elemFM` name_env)) mentioned
546 rnForAll doc (map UserTyVar forall_tyvars) ctxt ty
548 rnHsType doc (HsForAllTy (Just forall_tyvars) ctxt tau)
549 -- Explicit quantification.
550 -- Check that the forall'd tyvars are actually
551 -- mentioned in the type, and produce a warning if not
553 mentioned_in_tau = extractHsTyRdrTyVars tau
554 mentioned_in_ctxt = extractHsCtxtRdrTyVars ctxt
555 mentioned = nub (mentioned_in_tau ++ mentioned_in_ctxt)
556 forall_tyvar_names = hsTyVarNames forall_tyvars
558 -- Explicitly quantified but not mentioned in ctxt or tau
559 warn_guys = filter (`notElem` mentioned) forall_tyvar_names
561 mapRn_ (forAllWarn doc tau) warn_guys `thenRn_`
562 rnForAll doc forall_tyvars ctxt tau
564 rnHsType doc (HsTyVar tyvar)
565 = lookupOccRn tyvar `thenRn` \ tyvar' ->
566 returnRn (HsTyVar tyvar', unitFV tyvar')
568 rnHsType doc (HsFunTy ty1 ty2)
569 = rnHsType doc ty1 `thenRn` \ (ty1', fvs1) ->
570 -- Might find a for-all as the arg of a function type
571 rnHsType doc ty2 `thenRn` \ (ty2', fvs2) ->
572 -- Or as the result. This happens when reading Prelude.hi
573 -- when we find return :: forall m. Monad m -> forall a. a -> m a
574 returnRn (HsFunTy ty1' ty2', fvs1 `plusFV` fvs2)
576 rnHsType doc (HsListTy ty)
577 = rnHsType doc ty `thenRn` \ (ty', fvs) ->
578 returnRn (HsListTy ty', fvs `addOneFV` listTyCon_name)
580 -- Unboxed tuples are allowed to have poly-typed arguments. These
581 -- sometimes crop up as a result of CPR worker-wrappering dictionaries.
582 rnHsType doc (HsTupleTy (HsTupCon _ boxity) tys)
583 -- Don't do lookupOccRn, because this is built-in syntax
584 -- so it doesn't need to be in scope
585 = mapFvRn (rnHsType doc) tys `thenRn` \ (tys', fvs) ->
586 returnRn (HsTupleTy (HsTupCon n' boxity) tys', fvs `addOneFV` n')
588 n' = tupleTyCon_name boxity (length tys)
591 rnHsType doc (HsAppTy ty1 ty2)
592 = rnHsType doc ty1 `thenRn` \ (ty1', fvs1) ->
593 rnHsType doc ty2 `thenRn` \ (ty2', fvs2) ->
594 returnRn (HsAppTy ty1' ty2', fvs1 `plusFV` fvs2)
596 rnHsType doc (HsPredTy pred)
597 = rnPred doc pred `thenRn` \ (pred', fvs) ->
598 returnRn (HsPredTy pred', fvs)
600 rnHsType doc (HsUsgForAllTy uv_rdr ty)
601 = bindUVarRn doc uv_rdr $ \ uv_name ->
602 rnHsType doc ty `thenRn` \ (ty', fvs) ->
603 returnRn (HsUsgForAllTy uv_name ty',
606 rnHsType doc (HsUsgTy usg ty)
607 = newUsg usg `thenRn` \ (usg', usg_fvs) ->
608 rnHsType doc ty `thenRn` \ (ty', ty_fvs) ->
609 -- A for-all can occur inside a usage annotation
610 returnRn (HsUsgTy usg' ty',
611 usg_fvs `plusFV` ty_fvs)
613 newUsg usg = case usg of
614 HsUsOnce -> returnRn (HsUsOnce, emptyFVs)
615 HsUsMany -> returnRn (HsUsMany, emptyFVs)
616 HsUsVar uv_rdr -> lookupOccRn uv_rdr `thenRn` \ uv_name ->
617 returnRn (HsUsVar uv_name, emptyFVs)
619 rnHsTypes doc tys = mapFvRn (rnHsType doc) tys
623 -- We use lookupOcc here because this is interface file only stuff
624 -- and we need the workers...
625 rnHsTupCon (HsTupCon n boxity)
626 = lookupOccRn n `thenRn` \ n' ->
627 returnRn (HsTupCon n' boxity, unitFV n')
629 rnHsTupConWkr (HsTupCon n boxity)
630 -- Tuple construtors are for the *worker* of the tuple
631 -- Going direct saves needless messing about
632 = lookupOccRn (mkRdrNameWkr n) `thenRn` \ n' ->
633 returnRn (HsTupCon n' boxity, unitFV n')
637 rnForAll doc forall_tyvars ctxt ty
638 = bindTyVarsFVRn doc forall_tyvars $ \ new_tyvars ->
639 rnContext doc ctxt `thenRn` \ (new_ctxt, cxt_fvs) ->
640 rnHsType doc ty `thenRn` \ (new_ty, ty_fvs) ->
641 returnRn (mkHsForAllTy (Just new_tyvars) new_ctxt new_ty,
642 cxt_fvs `plusFV` ty_fvs)
646 rnContext :: SDoc -> RdrNameContext -> RnMS (RenamedContext, FreeVars)
648 = mapAndUnzipRn rn_pred ctxt `thenRn` \ (theta, fvs_s) ->
650 (_, dups) = removeDupsEq theta
651 -- We only have equality, not ordering
653 -- Check for duplicate assertions
654 -- If this isn't an error, then it ought to be:
655 mapRn (addWarnRn . dupClassAssertWarn theta) dups `thenRn_`
656 returnRn (theta, plusFVs fvs_s)
658 --Someone discovered that @CCallable@ and @CReturnable@
659 -- could be used in contexts such as:
660 -- foo :: CCallable a => a -> PrimIO Int
661 -- Doing this utterly wrecks the whole point of introducing these
662 -- classes so we specifically check that this isn't being done.
663 rn_pred pred = rnPred doc pred `thenRn` \ (pred', fvs)->
664 checkRn (not (bad_pred pred'))
665 (naughtyCCallContextErr pred') `thenRn_`
666 returnRn (pred', fvs)
668 bad_pred (HsPClass clas _) = getUnique clas `elem` cCallishClassKeys
669 bad_pred other = False
672 rnPred doc (HsPClass clas tys)
673 = lookupOccRn clas `thenRn` \ clas_name ->
674 rnHsTypes doc tys `thenRn` \ (tys', fvs) ->
675 returnRn (HsPClass clas_name tys', fvs `addOneFV` clas_name)
677 rnPred doc (HsPIParam n ty)
678 = newIPName n `thenRn` \ name ->
679 rnHsType doc ty `thenRn` \ (ty', fvs) ->
680 returnRn (HsPIParam name ty', fvs)
684 rnFds :: SDoc -> [FunDep RdrName] -> RnMS ([FunDep Name], FreeVars)
687 = mapAndUnzipRn rn_fds fds `thenRn` \ (theta, fvs_s) ->
688 returnRn (theta, plusFVs fvs_s)
691 = rnHsTyVars doc tys1 `thenRn` \ (tys1', fvs1) ->
692 rnHsTyVars doc tys2 `thenRn` \ (tys2', fvs2) ->
693 returnRn ((tys1', tys2'), fvs1 `plusFV` fvs2)
695 rnHsTyVars doc tvs = mapFvRn (rnHsTyvar doc) tvs
697 = lookupOccRn tyvar `thenRn` \ tyvar' ->
698 returnRn (tyvar', unitFV tyvar')
701 %*********************************************************
705 %*********************************************************
708 rnIdInfo (HsStrictness str) = returnRn (HsStrictness str, emptyFVs)
710 rnIdInfo (HsWorker worker)
711 = lookupOccRn worker `thenRn` \ worker' ->
712 returnRn (HsWorker worker', unitFV worker')
714 rnIdInfo (HsUnfold inline expr) = rnCoreExpr expr `thenRn` \ (expr', fvs) ->
715 returnRn (HsUnfold inline expr', fvs)
716 rnIdInfo (HsArity arity) = returnRn (HsArity arity, emptyFVs)
717 rnIdInfo HsNoCafRefs = returnRn (HsNoCafRefs, emptyFVs)
718 rnIdInfo HsCprInfo = returnRn (HsCprInfo, emptyFVs)
722 @UfCore@ expressions.
725 rnCoreExpr (UfType ty)
726 = rnHsType (text "unfolding type") ty `thenRn` \ (ty', fvs) ->
727 returnRn (UfType ty', fvs)
730 = lookupOccRn v `thenRn` \ v' ->
731 returnRn (UfVar v', unitFV v')
734 = returnRn (UfLit l, emptyFVs)
736 rnCoreExpr (UfLitLit l ty)
737 = rnHsType (text "litlit") ty `thenRn` \ (ty', fvs) ->
738 returnRn (UfLitLit l ty', fvs)
740 rnCoreExpr (UfCCall cc ty)
741 = rnHsType (text "ccall") ty `thenRn` \ (ty', fvs) ->
742 returnRn (UfCCall cc ty', fvs)
744 rnCoreExpr (UfTuple con args)
745 = rnHsTupConWkr con `thenRn` \ (con', fvs1) ->
746 mapFvRn rnCoreExpr args `thenRn` \ (args', fvs2) ->
747 returnRn (UfTuple con' args', fvs1 `plusFV` fvs2)
749 rnCoreExpr (UfApp fun arg)
750 = rnCoreExpr fun `thenRn` \ (fun', fv1) ->
751 rnCoreExpr arg `thenRn` \ (arg', fv2) ->
752 returnRn (UfApp fun' arg', fv1 `plusFV` fv2)
754 rnCoreExpr (UfCase scrut bndr alts)
755 = rnCoreExpr scrut `thenRn` \ (scrut', fvs1) ->
756 bindCoreLocalFVRn bndr ( \ bndr' ->
757 mapFvRn rnCoreAlt alts `thenRn` \ (alts', fvs2) ->
758 returnRn (UfCase scrut' bndr' alts', fvs2)
759 ) `thenRn` \ (case', fvs3) ->
760 returnRn (case', fvs1 `plusFV` fvs3)
762 rnCoreExpr (UfNote note expr)
763 = rnNote note `thenRn` \ (note', fvs1) ->
764 rnCoreExpr expr `thenRn` \ (expr', fvs2) ->
765 returnRn (UfNote note' expr', fvs1 `plusFV` fvs2)
767 rnCoreExpr (UfLam bndr body)
768 = rnCoreBndr bndr $ \ bndr' ->
769 rnCoreExpr body `thenRn` \ (body', fvs) ->
770 returnRn (UfLam bndr' body', fvs)
772 rnCoreExpr (UfLet (UfNonRec bndr rhs) body)
773 = rnCoreExpr rhs `thenRn` \ (rhs', fvs1) ->
774 rnCoreBndr bndr ( \ bndr' ->
775 rnCoreExpr body `thenRn` \ (body', fvs2) ->
776 returnRn (UfLet (UfNonRec bndr' rhs') body', fvs2)
777 ) `thenRn` \ (result, fvs3) ->
778 returnRn (result, fvs1 `plusFV` fvs3)
780 rnCoreExpr (UfLet (UfRec pairs) body)
781 = rnCoreBndrs bndrs $ \ bndrs' ->
782 mapFvRn rnCoreExpr rhss `thenRn` \ (rhss', fvs1) ->
783 rnCoreExpr body `thenRn` \ (body', fvs2) ->
784 returnRn (UfLet (UfRec (bndrs' `zip` rhss')) body', fvs1 `plusFV` fvs2)
786 (bndrs, rhss) = unzip pairs
790 rnCoreBndr (UfValBinder name ty) thing_inside
791 = rnHsType doc ty `thenRn` \ (ty', fvs1) ->
792 bindCoreLocalFVRn name ( \ name' ->
793 thing_inside (UfValBinder name' ty')
794 ) `thenRn` \ (result, fvs2) ->
795 returnRn (result, fvs1 `plusFV` fvs2)
797 doc = text "unfolding id"
799 rnCoreBndr (UfTyBinder name kind) thing_inside
800 = bindCoreLocalFVRn name $ \ name' ->
801 thing_inside (UfTyBinder name' kind)
803 rnCoreBndrs [] thing_inside = thing_inside []
804 rnCoreBndrs (b:bs) thing_inside = rnCoreBndr b $ \ name' ->
805 rnCoreBndrs bs $ \ names' ->
806 thing_inside (name':names')
810 rnCoreAlt (con, bndrs, rhs)
811 = rnUfCon con bndrs `thenRn` \ (con', fvs1) ->
812 bindCoreLocalsFVRn bndrs ( \ bndrs' ->
813 rnCoreExpr rhs `thenRn` \ (rhs', fvs2) ->
814 returnRn ((con', bndrs', rhs'), fvs2)
815 ) `thenRn` \ (result, fvs3) ->
816 returnRn (result, fvs1 `plusFV` fvs3)
819 = rnHsType (text "unfolding coerce") ty `thenRn` \ (ty', fvs) ->
820 returnRn (UfCoerce ty', fvs)
822 rnNote (UfSCC cc) = returnRn (UfSCC cc, emptyFVs)
823 rnNote UfInlineCall = returnRn (UfInlineCall, emptyFVs)
824 rnNote UfInlineMe = returnRn (UfInlineMe, emptyFVs)
828 = returnRn (UfDefault, emptyFVs)
830 rnUfCon (UfTupleAlt tup_con) bndrs
831 = rnHsTupCon tup_con `thenRn` \ (HsTupCon con' _, fvs) ->
832 returnRn (UfDataAlt con', fvs)
833 -- Makes the type checker a little easier
835 rnUfCon (UfDataAlt con) _
836 = lookupOccRn con `thenRn` \ con' ->
837 returnRn (UfDataAlt con', unitFV con')
839 rnUfCon (UfLitAlt lit) _
840 = returnRn (UfLitAlt lit, emptyFVs)
842 rnUfCon (UfLitLitAlt lit ty) _
843 = rnHsType (text "litlit") ty `thenRn` \ (ty', fvs) ->
844 returnRn (UfLitLitAlt lit ty', fvs)
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")]
877 classTyVarNotInOpTyErr clas_tyvar sig
878 = hang (hsep [ptext SLIT("Class type variable"),
879 quotes (ppr clas_tyvar),
880 ptext SLIT("does not appear in method signature")])
884 = hsep [ptext SLIT("Illegal data constructor name"), quotes (ppr name)]
886 forAllWarn doc ty tyvar
887 | not opt_WarnUnusedMatches = returnRn ()
889 = getModeRn `thenRn` \ mode ->
892 InterfaceMode -> returnRn () ; -- Don't warn of unused tyvars in interface files
893 -- unless DEBUG is on, in which case it is slightly
894 -- informative. They can arise from mkRhsTyLam,
895 #endif -- leading to (say) f :: forall a b. [b] -> [b]
899 sep [ptext SLIT("The universally quantified type variable") <+> quotes (ppr tyvar),
900 nest 4 (ptext SLIT("does not appear in the type") <+> quotes (ppr ty))]
902 (ptext SLIT("In") <+> doc))
905 forAllErr doc ty tyvar
907 sep [ptext SLIT("The constrained type variable") <+> quotes (ppr tyvar),
908 nest 4 (ptext SLIT("does not appear in the type") <+> quotes (ppr ty))]
910 (ptext SLIT("In") <+> doc))
912 badRuleLhsErr name lhs
913 = sep [ptext SLIT("Rule") <+> ptext name <> colon,
914 nest 4 (ptext SLIT("Illegal left-hand side:") <+> ppr lhs)]
916 ptext SLIT("LHS must be of form (f e1 .. en) where f is not forall'd")
919 = sep [ptext SLIT("Rule") <+> ptext name <> colon,
920 ptext SLIT("Forall'd variable") <+> quotes (ppr var) <+>
921 ptext SLIT("does not appear on left hand side")]
923 badExtName :: ExtName -> Message
925 = sep [quotes (ppr ext_nm) <+> ptext SLIT("is not a valid C identifier")]
927 dupClassAssertWarn ctxt (assertion : dups)
928 = sep [hsep [ptext SLIT("Duplicate class assertion"),
929 quotes (ppr assertion),
930 ptext SLIT("in the context:")],
931 nest 4 (pprHsContext ctxt <+> ptext SLIT("..."))]
933 naughtyCCallContextErr (HsPClass clas _)
934 = sep [ptext SLIT("Can't use class") <+> quotes (ppr clas),
935 ptext SLIT("in a context")]