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 ( getTyVarName, pprClassAssertion, cmpHsTypes )
15 import RdrName ( RdrName, isRdrDataCon, rdrNameOcc, isRdrTyVar )
16 import RdrHsSyn ( RdrNameContext, RdrNameHsType, RdrNameConDecl,
17 extractRuleBndrsTyVars, extractHsTyRdrTyVars
22 import RnBinds ( rnTopBinds, rnMethodBinds, renameSigs, unknownSigErr )
23 import RnEnv ( bindTyVarsRn, lookupBndrRn, lookupOccRn,
25 bindLocalsRn, bindLocalRn, bindLocalsFVRn,
26 bindTyVarsFVRn, bindTyVarsFV2Rn, extendTyVarEnvFVRn,
27 bindCoreLocalFVRn, bindCoreLocalsFVRn,
28 checkDupOrQualNames, checkDupNames,
29 mkImportedGlobalName, mkImportedGlobalFromRdrName,
30 newDFunName, getDFunKey, newImplicitBinder,
31 FreeVars, emptyFVs, plusFV, plusFVs, unitFV, addOneFV, mapFvRn
35 import Name ( Name, OccName,
36 ExportFlag(..), Provenance(..),
37 nameOccName, NamedThing(..)
40 import OccName ( mkDefaultMethodOcc )
41 import BasicTypes ( TopLevelFlag(..) )
42 import FiniteMap ( elemFM )
43 import PrelInfo ( derivableClassKeys,
44 deRefStablePtr_NAME, makeStablePtr_NAME, bindIO_NAME
46 import Bag ( bagToList )
47 import List ( partition, nub )
49 import SrcLoc ( SrcLoc )
50 import CmdLineOpts ( opt_WarnUnusedMatches ) -- Warn of unused for-all'd tyvars
51 import Unique ( Uniquable(..) )
52 import UniqFM ( lookupUFM )
53 import Maybes ( maybeToBool, catMaybes )
57 @rnDecl@ `renames' declarations.
58 It simultaneously performs dependency analysis and precedence parsing.
59 It also does the following error checks:
62 Checks that tyvars are used properly. This includes checking
63 for undefined tyvars, and tyvars in contexts that are ambiguous.
65 Checks that all variable occurences are defined.
67 Checks the @(..)@ etc constraints in the export list.
71 %*********************************************************
73 \subsection{Value declarations}
75 %*********************************************************
78 rnSourceDecls :: [RdrNameHsDecl] -> RnMS ([RenamedHsDecl], FreeVars)
79 -- The decls get reversed, but that's ok
82 = go emptyFVs [] decls
84 -- Fixity decls have been dealt with already; ignore them
85 go fvs ds' [] = returnRn (ds', fvs)
86 go fvs ds' (FixD _: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)
106 rnDecl (SigD (IfaceSig name ty id_infos loc))
108 lookupBndrRn name `thenRn` \ name' ->
109 rnHsType doc_str ty `thenRn` \ (ty',fvs1) ->
110 mapFvRn rnIdInfo id_infos `thenRn` \ (id_infos', fvs2) ->
111 returnRn (SigD (IfaceSig name' ty' id_infos' loc), fvs1 `plusFV` fvs2)
113 doc_str = text "the interface signature for" <+> quotes (ppr name)
116 %*********************************************************
118 \subsection{Type declarations}
120 %*********************************************************
122 @rnTyDecl@ uses the `global name function' to create a new type
123 declaration in which local names have been replaced by their original
124 names, reporting any unknown names.
126 Renaming type variables is a pain. Because they now contain uniques,
127 it is necessary to pass in an association list which maps a parsed
128 tyvar to its @Name@ representation.
129 In some cases (type signatures of values),
130 it is even necessary to go over the type first
131 in order to get the set of tyvars used by it, make an assoc list,
132 and then go over it again to rename the tyvars!
133 However, we can also do some scoping checks at the same time.
136 rnDecl (TyClD (TyData new_or_data context tycon tyvars condecls derivings pragmas src_loc))
137 = pushSrcLocRn src_loc $
138 lookupBndrRn tycon `thenRn` \ tycon' ->
139 bindTyVarsFVRn data_doc tyvars $ \ tyvars' ->
140 rnContext data_doc context `thenRn` \ (context', cxt_fvs) ->
141 checkDupOrQualNames data_doc con_names `thenRn_`
142 mapFvRn rnConDecl condecls `thenRn` \ (condecls', con_fvs) ->
143 rnDerivs derivings `thenRn` \ (derivings', deriv_fvs) ->
144 ASSERT(isNoDataPragmas pragmas)
145 returnRn (TyClD (TyData new_or_data context' tycon' tyvars' condecls'
146 derivings' noDataPragmas src_loc),
147 cxt_fvs `plusFV` con_fvs `plusFV` deriv_fvs)
149 data_doc = text "the data type declaration for" <+> quotes (ppr tycon)
150 con_names = map conDeclName condecls
152 rnDecl (TyClD (TySynonym name tyvars ty src_loc))
153 = pushSrcLocRn src_loc $
154 lookupBndrRn name `thenRn` \ name' ->
155 bindTyVarsFVRn syn_doc tyvars $ \ tyvars' ->
156 rnHsType syn_doc ty `thenRn` \ (ty', ty_fvs) ->
157 returnRn (TyClD (TySynonym name' tyvars' ty' src_loc), ty_fvs)
159 syn_doc = text "the declaration for type synonym" <+> quotes (ppr name)
161 rnDecl (TyClD (ClassDecl context cname tyvars sigs mbinds pragmas
162 tname dname snames src_loc))
163 = pushSrcLocRn src_loc $
165 lookupBndrRn cname `thenRn` \ cname' ->
167 -- Deal with the implicit tycon and datacon name
168 -- They aren't in scope (because they aren't visible to the user)
169 -- and what we want to do is simply look them up in the cache;
170 -- we jolly well ought to get a 'hit' there!
171 -- So the 'Imported' part of this call is not relevant.
172 -- Unclean; but since these two are the only place this happens
173 -- I can't work up the energy to do it more beautifully
174 mkImportedGlobalFromRdrName tname `thenRn` \ tname' ->
175 mkImportedGlobalFromRdrName dname `thenRn` \ dname' ->
176 mapRn mkImportedGlobalFromRdrName snames `thenRn` \ snames' ->
178 -- Tyvars scope over bindings and context
179 bindTyVarsFV2Rn cls_doc tyvars ( \ clas_tyvar_names tyvars' ->
181 -- Check the superclasses
182 rnContext cls_doc context `thenRn` \ (context', cxt_fvs) ->
184 -- Check the signatures
186 -- First process the class op sigs, then the fixity sigs.
187 (op_sigs, non_op_sigs) = partition isClassOpSig sigs
188 (fix_sigs, non_sigs) = partition isFixitySig non_op_sigs
190 checkDupOrQualNames sig_doc sig_rdr_names_w_locs `thenRn_`
191 mapFvRn (rn_op cname' clas_tyvar_names) op_sigs
192 `thenRn` \ (sigs', sig_fvs) ->
193 mapRn_ (unknownSigErr) non_sigs `thenRn_`
195 binders = mkNameSet [ nm | (ClassOpSig nm _ _ _) <- sigs' ]
197 renameSigs False binders lookupOccRn fix_sigs
198 `thenRn` \ (fixs', fix_fvs) ->
201 checkDupOrQualNames meth_doc meth_rdr_names_w_locs `thenRn_`
203 `thenRn` \ (mbinds', meth_fvs) ->
205 -- Typechecker is responsible for checking that we only
206 -- give default-method bindings for things in this class.
207 -- The renamer *could* check this for class decls, but can't
208 -- for instance decls.
210 ASSERT(isNoClassPragmas pragmas)
211 returnRn (TyClD (ClassDecl context' cname' tyvars' (fixs' ++ sigs') mbinds'
212 NoClassPragmas tname' dname' snames' src_loc),
220 cls_doc = text "the declaration for class" <+> ppr cname
221 sig_doc = text "the signatures for class" <+> ppr cname
222 meth_doc = text "the default-methods for class" <+> ppr cname
224 sig_rdr_names_w_locs = [(op,locn) | ClassOpSig op _ _ locn <- sigs]
225 meth_rdr_names_w_locs = bagToList (collectMonoBinders mbinds)
226 meth_rdr_names = map fst meth_rdr_names_w_locs
228 rn_op clas clas_tyvars sig@(ClassOpSig op maybe_dm ty locn)
229 = pushSrcLocRn locn $
230 lookupBndrRn op `thenRn` \ op_name ->
232 -- Check the signature
233 rnHsSigType (quotes (ppr op)) ty `thenRn` \ (new_ty, op_ty_fvs) ->
235 check_in_op_ty clas_tyvar =
236 checkRn (clas_tyvar `elemNameSet` op_ty_fvs)
237 (classTyVarNotInOpTyErr clas_tyvar sig)
239 mapRn_ check_in_op_ty clas_tyvars `thenRn_`
241 -- Make the default-method name
242 getModeRn `thenRn` \ mode ->
243 (case (mode, maybe_dm) of
245 | op `elem` meth_rdr_names
246 -> -- Source class decl with an explicit method decl
247 newImplicitBinder (mkDefaultMethodOcc (rdrNameOcc op)) locn
248 `thenRn` \ dm_name ->
249 returnRn (Just dm_name, emptyFVs)
252 -> -- Source class dec, no explicit method decl
253 returnRn (Nothing, emptyFVs)
255 (InterfaceMode, Just dm_rdr_name)
256 -> -- Imported class that has a default method decl
257 -- See comments with tname, snames, above
258 lookupImplicitOccRn dm_rdr_name `thenRn` \ dm_name ->
259 returnRn (Just dm_name, unitFV dm_name)
260 -- An imported class decl mentions, rather than defines,
261 -- the default method, so we must arrange to pull it in
263 (InterfaceMode, Nothing)
264 -- Imported class with no default metho
265 -> returnRn (Nothing, emptyFVs)
266 ) `thenRn` \ (maybe_dm_name, dm_fvs) ->
268 returnRn (ClassOpSig op_name maybe_dm_name new_ty locn, op_ty_fvs `plusFV` dm_fvs)
272 %*********************************************************
274 \subsection{Instance declarations}
276 %*********************************************************
279 rnDecl (InstD (InstDecl inst_ty mbinds uprags dfun_rdr_name src_loc))
280 = pushSrcLocRn src_loc $
281 rnHsSigType (text "an instance decl") inst_ty `thenRn` \ (inst_ty', inst_fvs) ->
283 inst_tyvars = case inst_ty' of
284 HsForAllTy (Just inst_tyvars) _ _ -> inst_tyvars
286 -- (Slightly strangely) the forall-d tyvars scope over
287 -- the method bindings too
290 -- Rename the bindings
291 -- NB meth_names can be qualified!
292 checkDupNames meth_doc meth_names `thenRn_`
293 extendTyVarEnvFVRn inst_tyvars (
295 ) `thenRn` \ (mbinds', meth_fvs) ->
297 binders = mkNameSet (map fst (bagToList (collectMonoBinders mbinds')))
299 -- Delete sigs (&report) sigs that aren't allowed inside an
305 (ok_sigs, not_ok_idecl_sigs) = partition okInInstDecl uprags
307 okInInstDecl (FixSig _) = False
308 okInInstDecl (Sig _ _ _) = False
309 okInInstDecl _ = True
312 -- You can't have fixity decls & type signatures
313 -- within an instance declaration.
314 mapRn_ unknownSigErr not_ok_idecl_sigs `thenRn_`
316 -- Rename the prags and signatures.
317 -- Note that the type variables are not in scope here,
318 -- so that instance Eq a => Eq (T a) where
319 -- {-# SPECIALISE instance Eq a => Eq (T [a]) #-}
321 renameSigs False binders lookupOccRn ok_sigs `thenRn` \ (new_uprags, prag_fvs) ->
323 getModeRn `thenRn` \ mode ->
325 InterfaceMode -> lookupImplicitOccRn dfun_rdr_name `thenRn` \ dfun_name ->
326 returnRn (dfun_name, unitFV dfun_name)
327 SourceMode -> newDFunName (getDFunKey inst_ty') src_loc
328 `thenRn` \ dfun_name ->
329 returnRn (dfun_name, emptyFVs)
331 `thenRn` \ (dfun_name, dfun_fv) ->
333 -- The typechecker checks that all the bindings are for the right class.
334 returnRn (InstD (InstDecl inst_ty' mbinds' new_uprags dfun_name src_loc),
335 inst_fvs `plusFV` meth_fvs `plusFV` prag_fvs `plusFV` dfun_fv)
337 meth_doc = text "the bindings in an instance declaration"
338 meth_names = bagToList (collectMonoBinders mbinds)
341 %*********************************************************
343 \subsection{Default declarations}
345 %*********************************************************
348 rnDecl (DefD (DefaultDecl tys src_loc))
349 = pushSrcLocRn src_loc $
350 rnHsTypes doc_str tys `thenRn` \ (tys', fvs) ->
351 returnRn (DefD (DefaultDecl tys' src_loc), fvs)
353 doc_str = text "a `default' declaration"
356 %*********************************************************
358 \subsection{Foreign declarations}
360 %*********************************************************
363 rnDecl (ForD (ForeignDecl name imp_exp ty ext_nm cconv src_loc))
364 = pushSrcLocRn src_loc $
365 lookupBndrRn name `thenRn` \ name' ->
367 fvs1 = case imp_exp of
368 FoImport _ | not isDyn -> emptyFVs
370 FoExport | isDyn -> mkNameSet [makeStablePtr_NAME,
375 rnHsSigType fo_decl_msg ty `thenRn` \ (ty', fvs2) ->
376 returnRn (ForD (ForeignDecl name' imp_exp ty' ext_nm cconv src_loc),
379 fo_decl_msg = ptext SLIT("a foreign declaration")
380 isDyn = isDynamic ext_nm
383 %*********************************************************
387 %*********************************************************
390 rnDecl (RuleD (IfaceRuleDecl var body src_loc))
391 = pushSrcLocRn src_loc $
392 lookupOccRn var `thenRn` \ var' ->
393 rnRuleBody body `thenRn` \ (body', fvs) ->
394 returnRn (RuleD (IfaceRuleDecl var' body' src_loc), fvs `addOneFV` var')
396 rnDecl (RuleD (RuleDecl 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 (RuleDecl 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 tvs cxt details locn)
455 = pushSrcLocRn locn $
456 checkConName name `thenRn_`
457 lookupBndrRn name `thenRn` \ new_name ->
458 bindTyVarsFVRn doc tvs $ \ new_tyvars ->
459 rnContext doc cxt `thenRn` \ (new_context, cxt_fvs) ->
460 rnConDetails doc locn details `thenRn` \ (new_details, det_fvs) ->
461 returnRn (ConDecl new_name new_tyvars new_context new_details locn,
462 cxt_fvs `plusFV` det_fvs)
464 doc = text "the definition of data constructor" <+> quotes (ppr name)
466 rnConDetails doc locn (VanillaCon tys)
467 = mapFvRn (rnBangTy doc) tys `thenRn` \ (new_tys, fvs) ->
468 returnRn (VanillaCon new_tys, fvs)
470 rnConDetails doc locn (InfixCon ty1 ty2)
471 = rnBangTy doc ty1 `thenRn` \ (new_ty1, fvs1) ->
472 rnBangTy doc ty2 `thenRn` \ (new_ty2, fvs2) ->
473 returnRn (InfixCon new_ty1 new_ty2, fvs1 `plusFV` fvs2)
475 rnConDetails doc locn (NewCon ty mb_field)
476 = rnHsType doc ty `thenRn` \ (new_ty, fvs) ->
477 rn_field mb_field `thenRn` \ new_mb_field ->
478 returnRn (NewCon new_ty new_mb_field, fvs)
480 rn_field Nothing = returnRn Nothing
482 lookupBndrRn f `thenRn` \ new_f ->
483 returnRn (Just new_f)
485 rnConDetails doc locn (RecCon fields)
486 = checkDupOrQualNames doc field_names `thenRn_`
487 mapFvRn (rnField doc) fields `thenRn` \ (new_fields, fvs) ->
488 returnRn (RecCon new_fields, fvs)
490 field_names = [(fld, locn) | (flds, _) <- fields, fld <- flds]
492 rnField doc (names, ty)
493 = mapRn lookupBndrRn names `thenRn` \ new_names ->
494 rnBangTy doc ty `thenRn` \ (new_ty, fvs) ->
495 returnRn ((new_names, new_ty), fvs)
497 rnBangTy doc (Banged ty)
498 = rnHsType doc ty `thenRn` \ (new_ty, fvs) ->
499 returnRn (Banged new_ty, fvs)
501 rnBangTy doc (Unbanged ty)
502 = rnHsType doc ty `thenRn` \ (new_ty, fvs) ->
503 returnRn (Unbanged new_ty, fvs)
505 rnBangTy doc (Unpacked ty)
506 = rnHsType doc ty `thenRn` \ (new_ty, fvs) ->
507 returnRn (Unpacked new_ty, fvs)
509 -- This data decl will parse OK
511 -- treating "a" as the constructor.
512 -- It is really hard to make the parser spot this malformation.
513 -- So the renamer has to check that the constructor is legal
515 -- We can get an operator as the constructor, even in the prefix form:
516 -- data T = :% Int Int
517 -- from interface files, which always print in prefix form
520 = checkRn (isRdrDataCon name)
525 %*********************************************************
527 \subsection{Support code to rename types}
529 %*********************************************************
532 rnHsSigType :: SDoc -> RdrNameHsType -> RnMS (RenamedHsType, FreeVars)
533 -- rnHsSigType is used for source-language type signatures,
534 -- which use *implicit* universal quantification.
535 rnHsSigType doc_str ty
536 = rnHsType (text "the type signature for" <+> doc_str) ty
538 rnForAll doc forall_tyvars ctxt ty
539 = bindTyVarsFVRn doc forall_tyvars $ \ new_tyvars ->
540 rnContext doc ctxt `thenRn` \ (new_ctxt, cxt_fvs) ->
541 rnHsType doc ty `thenRn` \ (new_ty, ty_fvs) ->
542 returnRn (mkHsForAllTy new_tyvars new_ctxt new_ty,
543 cxt_fvs `plusFV` ty_fvs)
545 -- Check that each constraint mentions at least one of the forall'd type variables
546 -- Since the forall'd type variables are a subset of the free tyvars
547 -- of the tau-type part, this guarantees that every constraint mentions
548 -- at least one of the free tyvars in ty
549 checkConstraints explicit_forall doc forall_tyvars ctxt ty
550 = mapRn check ctxt `thenRn` \ maybe_ctxt' ->
551 returnRn (catMaybes maybe_ctxt')
552 -- Remove problem ones, to avoid duplicate error message.
555 | forall_mentioned = returnRn (Just ct)
556 | otherwise = addErrRn (ctxtErr explicit_forall doc forall_tyvars ct ty)
557 `thenRn_` returnRn Nothing
559 forall_mentioned = foldr ((||) . any (`elem` forall_tyvars) . extractHsTyRdrTyVars)
563 rnHsType :: SDoc -> RdrNameHsType -> RnMS (RenamedHsType, FreeVars)
565 rnHsType doc (HsForAllTy Nothing ctxt ty)
566 -- From source code (no kinds on tyvars)
567 -- Given the signature C => T we universally quantify
568 -- over FV(T) \ {in-scope-tyvars}
569 = getLocalNameEnv `thenRn` \ name_env ->
571 mentioned_in_tau = extractHsTyRdrTyVars ty
572 forall_tyvars = filter (not . (`elemFM` name_env)) mentioned_in_tau
574 checkConstraints False doc forall_tyvars ctxt ty `thenRn` \ ctxt' ->
575 rnForAll doc (map UserTyVar forall_tyvars) ctxt' ty
577 rnHsType doc (HsForAllTy (Just forall_tyvars) ctxt tau)
578 -- Explicit quantification.
579 -- Check that the forall'd tyvars are a subset of the
580 -- free tyvars in the tau-type part
581 -- That's only a warning... unless the tyvar is constrained by a
582 -- context in which case it's an error
584 mentioned_in_tau = extractHsTyRdrTyVars tau
585 mentioned_in_ctxt = nub [tv | (_,tys) <- ctxt,
587 tv <- extractHsTyRdrTyVars ty]
589 dubious_guys = filter (`notElem` mentioned_in_tau) forall_tyvar_names
590 -- dubious = explicitly quantified but not mentioned in tau type
592 (bad_guys, warn_guys) = partition (`elem` mentioned_in_ctxt) dubious_guys
593 -- bad = explicitly quantified and constrained, but not mentioned in tau
594 -- warn = explicitly quantified but not mentioned in ctxt or tau
596 forall_tyvar_names = map getTyVarName forall_tyvars
598 mapRn_ (forAllErr doc tau) bad_guys `thenRn_`
599 mapRn_ (forAllWarn doc tau) warn_guys `thenRn_`
600 checkConstraints True doc forall_tyvar_names ctxt tau `thenRn` \ ctxt' ->
601 rnForAll doc forall_tyvars ctxt' tau
603 rnHsType doc (MonoTyVar tyvar)
604 = lookupOccRn tyvar `thenRn` \ tyvar' ->
605 returnRn (MonoTyVar tyvar', unitFV tyvar')
607 rnHsType doc (MonoFunTy ty1 ty2)
608 = rnHsType doc ty1 `thenRn` \ (ty1', fvs1) ->
609 rnHsType doc ty2 `thenRn` \ (ty2', fvs2) ->
610 returnRn (MonoFunTy ty1' ty2', fvs1 `plusFV` fvs2)
612 rnHsType doc (MonoListTy ty)
613 = rnHsType doc ty `thenRn` \ (ty', fvs) ->
614 returnRn (MonoListTy ty', fvs `addOneFV` listTyCon_name)
616 rnHsType doc (MonoTupleTy tys boxed)
617 = rnHsTypes doc tys `thenRn` \ (tys', fvs) ->
618 returnRn (MonoTupleTy tys' boxed, fvs `addOneFV` tup_con_name)
620 tup_con_name = tupleTyCon_name boxed (length tys)
622 rnHsType doc (MonoTyApp ty1 ty2)
623 = rnHsType doc ty1 `thenRn` \ (ty1', fvs1) ->
624 rnHsType doc ty2 `thenRn` \ (ty2', fvs2) ->
625 returnRn (MonoTyApp ty1' ty2', fvs1 `plusFV` fvs2)
627 rnHsType doc (MonoDictTy clas tys)
628 = lookupOccRn clas `thenRn` \ clas' ->
629 rnHsTypes doc tys `thenRn` \ (tys', fvs) ->
630 returnRn (MonoDictTy clas' tys', fvs `addOneFV` clas')
632 rnHsType doc (MonoUsgTy usg ty)
633 = rnHsType doc ty `thenRn` \ (ty', fvs) ->
634 returnRn (MonoUsgTy usg ty', fvs)
636 rnHsTypes doc tys = mapFvRn (rnHsType doc) tys
641 rnContext :: SDoc -> RdrNameContext -> RnMS (RenamedContext, FreeVars)
644 = mapAndUnzipRn rn_ctxt ctxt `thenRn` \ (theta, fvs_s) ->
646 (_, dup_asserts) = removeDups cmp_assert theta
648 -- Check for duplicate assertions
649 -- If this isn't an error, then it ought to be:
650 mapRn_ (addWarnRn . dupClassAssertWarn theta) dup_asserts `thenRn_`
652 returnRn (theta, plusFVs fvs_s)
655 = lookupOccRn clas `thenRn` \ clas_name ->
656 rnHsTypes doc tys `thenRn` \ (tys', fvs) ->
657 returnRn ((clas_name, tys'), fvs `addOneFV` clas_name)
659 cmp_assert (c1,tys1) (c2,tys2)
660 = (c1 `compare` c2) `thenCmp` (cmpHsTypes compare tys1 tys2)
664 %*********************************************************
668 %*********************************************************
671 rnIdInfo (HsStrictness str) = returnRn (HsStrictness str, emptyFVs)
673 rnIdInfo (HsWorker worker)
674 = lookupOccRn worker `thenRn` \ worker' ->
675 returnRn (HsWorker worker', unitFV worker')
677 rnIdInfo (HsUnfold inline (Just expr)) = rnCoreExpr expr `thenRn` \ (expr', fvs) ->
678 returnRn (HsUnfold inline (Just expr'), fvs)
679 rnIdInfo (HsUnfold inline Nothing) = returnRn (HsUnfold inline Nothing, emptyFVs)
680 rnIdInfo (HsArity arity) = returnRn (HsArity arity, emptyFVs)
681 rnIdInfo (HsUpdate update) = returnRn (HsUpdate update, emptyFVs)
682 rnIdInfo (HsNoCafRefs) = returnRn (HsNoCafRefs, emptyFVs)
683 rnIdInfo (HsCprInfo cpr_info) = returnRn (HsCprInfo cpr_info, emptyFVs)
684 rnIdInfo (HsSpecialise rule_body) = rnRuleBody rule_body
685 `thenRn` \ (rule_body', fvs) ->
686 returnRn (HsSpecialise rule_body', fvs)
688 rnRuleBody (UfRuleBody str vars args rhs)
689 = rnCoreBndrs vars $ \ vars' ->
690 mapFvRn rnCoreExpr args `thenRn` \ (args', fvs1) ->
691 rnCoreExpr rhs `thenRn` \ (rhs', fvs2) ->
692 returnRn (UfRuleBody str vars' args' rhs', fvs1 `plusFV` fvs2)
695 @UfCore@ expressions.
698 rnCoreExpr (UfType ty)
699 = rnHsType (text "unfolding type") ty `thenRn` \ (ty', fvs) ->
700 returnRn (UfType ty', fvs)
703 = lookupOccRn v `thenRn` \ v' ->
704 returnRn (UfVar v', unitFV v')
706 rnCoreExpr (UfCon con args)
707 = rnUfCon con `thenRn` \ (con', fvs1) ->
708 mapFvRn rnCoreExpr args `thenRn` \ (args', fvs2) ->
709 returnRn (UfCon con' args', fvs1 `plusFV` fvs2)
711 rnCoreExpr (UfTuple con args)
712 = lookupOccRn con `thenRn` \ con' ->
713 mapFvRn rnCoreExpr args `thenRn` \ (args', fvs) ->
714 returnRn (UfTuple con' args', fvs `addOneFV` con')
716 rnCoreExpr (UfApp fun arg)
717 = rnCoreExpr fun `thenRn` \ (fun', fv1) ->
718 rnCoreExpr arg `thenRn` \ (arg', fv2) ->
719 returnRn (UfApp fun' arg', fv1 `plusFV` fv2)
721 rnCoreExpr (UfCase scrut bndr alts)
722 = rnCoreExpr scrut `thenRn` \ (scrut', fvs1) ->
723 bindCoreLocalFVRn bndr ( \ bndr' ->
724 mapFvRn rnCoreAlt alts `thenRn` \ (alts', fvs2) ->
725 returnRn (UfCase scrut' bndr' alts', fvs2)
726 ) `thenRn` \ (case', fvs3) ->
727 returnRn (case', fvs1 `plusFV` fvs3)
729 rnCoreExpr (UfNote note expr)
730 = rnNote note `thenRn` \ (note', fvs1) ->
731 rnCoreExpr expr `thenRn` \ (expr', fvs2) ->
732 returnRn (UfNote note' expr', fvs1 `plusFV` fvs2)
734 rnCoreExpr (UfLam bndr body)
735 = rnCoreBndr bndr $ \ bndr' ->
736 rnCoreExpr body `thenRn` \ (body', fvs) ->
737 returnRn (UfLam bndr' body', fvs)
739 rnCoreExpr (UfLet (UfNonRec bndr rhs) body)
740 = rnCoreExpr rhs `thenRn` \ (rhs', fvs1) ->
741 rnCoreBndr bndr ( \ bndr' ->
742 rnCoreExpr body `thenRn` \ (body', fvs2) ->
743 returnRn (UfLet (UfNonRec bndr' rhs') body', fvs2)
744 ) `thenRn` \ (result, fvs3) ->
745 returnRn (result, fvs1 `plusFV` fvs3)
747 rnCoreExpr (UfLet (UfRec pairs) body)
748 = rnCoreBndrs bndrs $ \ bndrs' ->
749 mapFvRn rnCoreExpr rhss `thenRn` \ (rhss', fvs1) ->
750 rnCoreExpr body `thenRn` \ (body', fvs2) ->
751 returnRn (UfLet (UfRec (bndrs' `zip` rhss')) body', fvs1 `plusFV` fvs2)
753 (bndrs, rhss) = unzip pairs
757 rnCoreBndr (UfValBinder name ty) thing_inside
758 = rnHsType doc ty `thenRn` \ (ty', fvs1) ->
759 bindCoreLocalFVRn name ( \ name' ->
760 thing_inside (UfValBinder name' ty')
761 ) `thenRn` \ (result, fvs2) ->
762 returnRn (result, fvs1 `plusFV` fvs2)
764 doc = text "unfolding id"
766 rnCoreBndr (UfTyBinder name kind) thing_inside
767 = bindCoreLocalFVRn name $ \ name' ->
768 thing_inside (UfTyBinder name' kind)
770 rnCoreBndrs [] thing_inside = thing_inside []
771 rnCoreBndrs (b:bs) thing_inside = rnCoreBndr b $ \ name' ->
772 rnCoreBndrs bs $ \ names' ->
773 thing_inside (name':names')
777 rnCoreAlt (con, bndrs, rhs)
778 = rnUfCon con `thenRn` \ (con', fvs1) ->
779 bindCoreLocalsFVRn bndrs ( \ bndrs' ->
780 rnCoreExpr rhs `thenRn` \ (rhs', fvs2) ->
781 returnRn ((con', bndrs', rhs'), fvs2)
782 ) `thenRn` \ (result, fvs3) ->
783 returnRn (result, fvs1 `plusFV` fvs3)
786 = rnHsType (text "unfolding coerce") ty `thenRn` \ (ty', fvs) ->
787 returnRn (UfCoerce ty', fvs)
789 rnNote (UfSCC cc) = returnRn (UfSCC cc, emptyFVs)
790 rnNote UfInlineCall = returnRn (UfInlineCall, emptyFVs)
791 rnNote UfInlineMe = returnRn (UfInlineMe, emptyFVs)
795 = returnRn (UfDefault, emptyFVs)
797 rnUfCon (UfDataCon con)
798 = lookupOccRn con `thenRn` \ con' ->
799 returnRn (UfDataCon con', unitFV con')
801 rnUfCon (UfLitCon lit)
802 = returnRn (UfLitCon lit, emptyFVs)
804 rnUfCon (UfLitLitCon lit ty)
805 = rnHsType (text "litlit") ty `thenRn` \ (ty', fvs) ->
806 returnRn (UfLitLitCon lit ty', fvs)
808 rnUfCon (UfPrimOp op)
809 = lookupOccRn op `thenRn` \ op' ->
810 returnRn (UfPrimOp op', emptyFVs)
812 rnUfCon (UfCCallOp str is_dyn casm gc)
813 = returnRn (UfCCallOp str is_dyn casm gc, emptyFVs)
816 %*********************************************************
818 \subsection{Rule shapes}
820 %*********************************************************
822 Check the shape of a transformation rule LHS. Currently
823 we only allow LHSs of the form @(f e1 .. en)@, where @f@ is
824 not one of the @forall@'d variables.
827 validRuleLhs foralls lhs
830 check (HsApp e1 e2) = check e1
831 check (HsVar v) | v `notElem` foralls = True
836 %*********************************************************
840 %*********************************************************
843 derivingNonStdClassErr clas
844 = hsep [ptext SLIT("non-standard class"), ppr clas, ptext SLIT("in deriving clause")]
846 classTyVarNotInOpTyErr clas_tyvar sig
847 = hang (hsep [ptext SLIT("Class type variable"),
848 quotes (ppr clas_tyvar),
849 ptext SLIT("does not appear in method signature")])
852 dupClassAssertWarn ctxt (assertion : dups)
853 = sep [hsep [ptext SLIT("Duplicate class assertion"),
854 quotes (pprClassAssertion assertion),
855 ptext SLIT("in the context:")],
856 nest 4 (pprContext ctxt <+> ptext SLIT("..."))]
859 = hsep [ptext SLIT("Illegal data constructor name"), quotes (ppr name)]
861 forAllWarn doc ty tyvar
862 | not opt_WarnUnusedMatches = returnRn ()
864 = getModeRn `thenRn` \ mode ->
867 InterfaceMode -> returnRn () ; -- Don't warn of unused tyvars in interface files
868 -- unless DEBUG is on, in which case it is slightly
869 -- informative. They can arise from mkRhsTyLam,
870 #endif -- leading to (say) f :: forall a b. [b] -> [b]
874 sep [ptext SLIT("The universally quantified type variable") <+> quotes (ppr tyvar),
875 nest 4 (ptext SLIT("does not appear in the type") <+> quotes (ppr ty))]
877 (ptext SLIT("In") <+> doc))
880 forAllErr doc ty tyvar
882 sep [ptext SLIT("The constrained type variable") <+> quotes (ppr tyvar),
883 nest 4 (ptext SLIT("does not appear in the type") <+> quotes (ppr ty))]
885 (ptext SLIT("In") <+> doc))
887 ctxtErr explicit_forall doc tyvars constraint ty
888 = sep [ptext SLIT("None of the type variable(s) in the constraint")
889 <+> quotes (pprClassAssertion constraint),
890 if explicit_forall then
891 nest 4 (ptext SLIT("is universally quantified (i.e. bound by the forall)"))
893 nest 4 (ptext SLIT("appears in the type") <+> quotes (ppr ty))
896 (ptext SLIT("In") <+> doc)
898 badRuleLhsErr name lhs
899 = sep [ptext SLIT("Rule") <+> ptext name <> colon,
900 nest 4 (ptext SLIT("Illegal left-hand side:") <+> ppr lhs)]
902 ptext SLIT("LHS must be of form (f e1 .. en) where f is not forall'd")
905 = sep [ptext SLIT("Rule") <+> ptext name <> colon,
906 ptext SLIT("Forall'd variable") <+> quotes (ppr var) <+>
907 ptext SLIT("does not appear on left hand side")]