2 % (c) The University of Glasgow 2006
3 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
6 Type checking of type signatures in interface files
10 tcImportDecl, checkWiredInTyCon, tcHiBootIface, typecheckIface,
11 tcIfaceDecl, tcIfaceInst, tcIfaceFamInst, tcIfaceRules,
12 tcIfaceVectInfo, tcIfaceAnnotations, tcIfaceGlobal, tcExtCoreBindings
15 #include "HsVersions.h"
56 import BasicTypes (Arity)
69 An IfaceDecl is populated with RdrNames, and these are not renamed to
70 Names before typechecking, because there should be no scope errors etc.
72 -- For (b) consider: f = \$(...h....)
73 -- where h is imported, and calls f via an hi-boot file.
74 -- This is bad! But it is not seen as a staging error, because h
75 -- is indeed imported. We don't want the type-checker to black-hole
76 -- when simplifying and compiling the splice!
78 -- Simple solution: discard any unfolding that mentions a variable
79 -- bound in this module (and hence not yet processed).
80 -- The discarding happens when forkM finds a type error.
82 %************************************************************************
84 %* tcImportDecl is the key function for "faulting in" *
87 %************************************************************************
89 The main idea is this. We are chugging along type-checking source code, and
90 find a reference to GHC.Base.map. We call tcLookupGlobal, which doesn't find
91 it in the EPS type envt. So it
93 2 gets the decl for GHC.Base.map
94 3 typechecks it via tcIfaceDecl
95 4 and adds it to the type env in the EPS
97 Note that DURING STEP 4, we may find that map's type mentions a type
100 Notice that for imported things we read the current version from the EPS
101 mutable variable. This is important in situations like
103 where the code that e1 expands to might import some defns that
104 also turn out to be needed by the code that e2 expands to.
107 tcImportDecl :: Name -> TcM TyThing
108 -- Entry point for *source-code* uses of importDecl
110 | Just thing <- wiredInNameTyThing_maybe name
111 = do { when (needWiredInHomeIface thing)
112 (initIfaceTcRn (loadWiredInHomeIface name))
113 -- See Note [Loading instances for wired-in things]
116 = do { traceIf (text "tcImportDecl" <+> ppr name)
117 ; mb_thing <- initIfaceTcRn (importDecl name)
119 Succeeded thing -> return thing
120 Failed err -> failWithTc err }
122 importDecl :: Name -> IfM lcl (MaybeErr Message TyThing)
123 -- Get the TyThing for this Name from an interface file
124 -- It's not a wired-in thing -- the caller caught that
126 = ASSERT( not (isWiredInName name) )
129 -- Load the interface, which should populate the PTE
130 ; mb_iface <- ASSERT2( isExternalName name, ppr name )
131 loadInterface nd_doc (nameModule name) ImportBySystem
133 Failed err_msg -> return (Failed err_msg) ;
136 -- Now look it up again; this time we should find it
138 ; case lookupTypeEnv (eps_PTE eps) name of
139 Just thing -> return (Succeeded thing)
140 Nothing -> return (Failed not_found_msg)
143 nd_doc = ptext (sLit "Need decl for") <+> ppr name
144 not_found_msg = hang (ptext (sLit "Can't find interface-file declaration for") <+>
145 pprNameSpace (occNameSpace (nameOccName name)) <+> ppr name)
146 2 (vcat [ptext (sLit "Probable cause: bug in .hi-boot file, or inconsistent .hi file"),
147 ptext (sLit "Use -ddump-if-trace to get an idea of which file caused the error")])
150 %************************************************************************
152 Checks for wired-in things
154 %************************************************************************
156 Note [Loading instances for wired-in things]
157 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
158 We need to make sure that we have at least *read* the interface files
159 for any module with an instance decl or RULE that we might want.
161 * If the instance decl is an orphan, we have a whole separate mechanism
164 * If the instance decl not an orphan, then the act of looking at the
165 TyCon or Class will force in the defining module for the
166 TyCon/Class, and hence the instance decl
168 * BUT, if the TyCon is a wired-in TyCon, we don't really need its interface;
169 but we must make sure we read its interface in case it has instances or
170 rules. That is what LoadIface.loadWiredInHomeInterface does. It's called
171 from TcIface.{tcImportDecl, checkWiredInTyCon, ifCheckWiredInThing}
173 * HOWEVER, only do this for TyCons. There are no wired-in Classes. There
174 are some wired-in Ids, but we don't want to load their interfaces. For
175 example, Control.Exception.Base.recSelError is wired in, but that module
176 is compiled late in the base library, and we don't want to force it to
177 load before it's been compiled!
179 All of this is done by the type checker. The renamer plays no role.
180 (It used to, but no longer.)
184 checkWiredInTyCon :: TyCon -> TcM ()
185 -- Ensure that the home module of the TyCon (and hence its instances)
186 -- are loaded. See Note [Loading instances for wired-in things]
187 -- It might not be a wired-in tycon (see the calls in TcUnify),
188 -- in which case this is a no-op.
190 | not (isWiredInName tc_name)
193 = do { mod <- getModule
194 ; ASSERT( isExternalName tc_name )
195 when (mod /= nameModule tc_name)
196 (initIfaceTcRn (loadWiredInHomeIface tc_name))
197 -- Don't look for (non-existent) Float.hi when
198 -- compiling Float.lhs, which mentions Float of course
199 -- A bit yukky to call initIfaceTcRn here
202 tc_name = tyConName tc
204 ifCheckWiredInThing :: TyThing -> IfL ()
205 -- Even though we are in an interface file, we want to make
206 -- sure the instances of a wired-in thing are loaded (imagine f :: Double -> Double)
207 -- Ditto want to ensure that RULES are loaded too
208 -- See Note [Loading instances for wired-in things]
209 ifCheckWiredInThing thing
210 = do { mod <- getIfModule
211 -- Check whether we are typechecking the interface for this
212 -- very module. E.g when compiling the base library in --make mode
213 -- we may typecheck GHC.Base.hi. At that point, GHC.Base is not in
214 -- the HPT, so without the test we'll demand-load it into the PIT!
215 -- C.f. the same test in checkWiredInTyCon above
216 ; let name = getName thing
217 ; ASSERT2( isExternalName name, ppr name )
218 when (needWiredInHomeIface thing && mod /= nameModule name)
219 (loadWiredInHomeIface name) }
221 needWiredInHomeIface :: TyThing -> Bool
222 -- Only for TyCons; see Note [Loading instances for wired-in things]
223 needWiredInHomeIface (ATyCon {}) = True
224 needWiredInHomeIface _ = False
227 %************************************************************************
229 Type-checking a complete interface
231 %************************************************************************
233 Suppose we discover we don't need to recompile. Then we must type
234 check the old interface file. This is a bit different to the
235 incremental type checking we do as we suck in interface files. Instead
236 we do things similarly as when we are typechecking source decls: we
237 bring into scope the type envt for the interface all at once, using a
238 knot. Remember, the decls aren't necessarily in dependency order --
239 and even if they were, the type decls might be mutually recursive.
242 typecheckIface :: ModIface -- Get the decls from here
243 -> TcRnIf gbl lcl ModDetails
245 = initIfaceTc iface $ \ tc_env_var -> do
246 -- The tc_env_var is freshly allocated, private to
247 -- type-checking this particular interface
248 { -- Get the right set of decls and rules. If we are compiling without -O
249 -- we discard pragmas before typechecking, so that we don't "see"
250 -- information that we shouldn't. From a versioning point of view
251 -- It's not actually *wrong* to do so, but in fact GHCi is unable
252 -- to handle unboxed tuples, so it must not see unfoldings.
253 ignore_prags <- doptM Opt_IgnoreInterfacePragmas
255 -- Typecheck the decls. This is done lazily, so that the knot-tying
256 -- within this single module work out right. In the If monad there is
257 -- no global envt for the current interface; instead, the knot is tied
258 -- through the if_rec_types field of IfGblEnv
259 ; names_w_things <- loadDecls ignore_prags (mi_decls iface)
260 ; let type_env = mkNameEnv names_w_things
261 ; writeMutVar tc_env_var type_env
263 -- Now do those rules, instances and annotations
264 ; insts <- mapM tcIfaceInst (mi_insts iface)
265 ; fam_insts <- mapM tcIfaceFamInst (mi_fam_insts iface)
266 ; rules <- tcIfaceRules ignore_prags (mi_rules iface)
267 ; anns <- tcIfaceAnnotations (mi_anns iface)
269 -- Vectorisation information
270 ; vect_info <- tcIfaceVectInfo (mi_module iface) type_env
274 ; exports <- ifaceExportNames (mi_exports iface)
277 ; traceIf (vcat [text "Finished typechecking interface for" <+> ppr (mi_module iface),
278 text "Type envt:" <+> ppr type_env])
279 ; return $ ModDetails { md_types = type_env
281 , md_fam_insts = fam_insts
284 , md_vect_info = vect_info
285 , md_exports = exports
291 %************************************************************************
293 Type and class declarations
295 %************************************************************************
298 tcHiBootIface :: HscSource -> Module -> TcRn ModDetails
299 -- Load the hi-boot iface for the module being compiled,
300 -- if it indeed exists in the transitive closure of imports
301 -- Return the ModDetails, empty if no hi-boot iface
302 tcHiBootIface hsc_src mod
303 | isHsBoot hsc_src -- Already compiling a hs-boot file
304 = return emptyModDetails
306 = do { traceIf (text "loadHiBootInterface" <+> ppr mod)
309 ; if not (isOneShot mode)
310 -- In --make and interactive mode, if this module has an hs-boot file
311 -- we'll have compiled it already, and it'll be in the HPT
313 -- We check wheher the interface is a *boot* interface.
314 -- It can happen (when using GHC from Visual Studio) that we
315 -- compile a module in TypecheckOnly mode, with a stable,
316 -- fully-populated HPT. In that case the boot interface isn't there
317 -- (it's been replaced by the mother module) so we can't check it.
318 -- And that's fine, because if M's ModInfo is in the HPT, then
319 -- it's been compiled once, and we don't need to check the boot iface
320 then do { hpt <- getHpt
321 ; case lookupUFM hpt (moduleName mod) of
322 Just info | mi_boot (hm_iface info)
323 -> return (hm_details info)
324 _ -> return emptyModDetails }
327 -- OK, so we're in one-shot mode.
328 -- In that case, we're read all the direct imports by now,
329 -- so eps_is_boot will record if any of our imports mention us by
330 -- way of hi-boot file
332 ; case lookupUFM (eps_is_boot eps) (moduleName mod) of {
333 Nothing -> return emptyModDetails ; -- The typical case
335 Just (_, False) -> failWithTc moduleLoop ;
336 -- Someone below us imported us!
337 -- This is a loop with no hi-boot in the way
339 Just (_mod, True) -> -- There's a hi-boot interface below us
341 do { read_result <- findAndReadIface
345 ; case read_result of
346 Failed err -> failWithTc (elaborate err)
347 Succeeded (iface, _path) -> typecheckIface iface
350 need = ptext (sLit "Need the hi-boot interface for") <+> ppr mod
351 <+> ptext (sLit "to compare against the Real Thing")
353 moduleLoop = ptext (sLit "Circular imports: module") <+> quotes (ppr mod)
354 <+> ptext (sLit "depends on itself")
356 elaborate err = hang (ptext (sLit "Could not find hi-boot interface for") <+>
357 quotes (ppr mod) <> colon) 4 err
361 %************************************************************************
363 Type and class declarations
365 %************************************************************************
367 When typechecking a data type decl, we *lazily* (via forkM) typecheck
368 the constructor argument types. This is in the hope that we may never
369 poke on those argument types, and hence may never need to load the
370 interface files for types mentioned in the arg types.
373 data Foo.S = MkS Baz.T
374 Mabye we can get away without even loading the interface for Baz!
376 This is not just a performance thing. Suppose we have
377 data Foo.S = MkS Baz.T
378 data Baz.T = MkT Foo.S
379 (in different interface files, of course).
380 Now, first we load and typecheck Foo.S, and add it to the type envt.
381 If we do explore MkS's argument, we'll load and typecheck Baz.T.
382 If we explore MkT's argument we'll find Foo.S already in the envt.
384 If we typechecked constructor args eagerly, when loading Foo.S we'd try to
385 typecheck the type Baz.T. So we'd fault in Baz.T... and then need Foo.S...
386 which isn't done yet.
388 All very cunning. However, there is a rather subtle gotcha which bit
389 me when developing this stuff. When we typecheck the decl for S, we
390 extend the type envt with S, MkS, and all its implicit Ids. Suppose
391 (a bug, but it happened) that the list of implicit Ids depended in
392 turn on the constructor arg types. Then the following sequence of
394 * we build a thunk <t> for the constructor arg tys
395 * we build a thunk for the extended type environment (depends on <t>)
396 * we write the extended type envt into the global EPS mutvar
398 Now we look something up in the type envt
400 * which reads the global type envt out of the global EPS mutvar
401 * but that depends in turn on <t>
403 It's subtle, because, it'd work fine if we typechecked the constructor args
404 eagerly -- they don't need the extended type envt. They just get the extended
405 type envt by accident, because they look at it later.
407 What this means is that the implicitTyThings MUST NOT DEPEND on any of
412 tcIfaceDecl :: Bool -- True <=> discard IdInfo on IfaceId bindings
416 tcIfaceDecl ignore_prags (IfaceId {ifName = occ_name, ifType = iface_type,
417 ifIdDetails = details, ifIdInfo = info})
418 = do { name <- lookupIfaceTop occ_name
419 ; ty <- tcIfaceType iface_type
420 ; details <- tcIdDetails details
421 ; info <- tcIdInfo ignore_prags name ty info
422 ; return (AnId (mkGlobalId details name ty info)) }
424 tcIfaceDecl _ (IfaceData {ifName = occ_name,
426 ifCtxt = ctxt, ifGadtSyntax = gadt_syn,
429 ifGeneric = want_generic,
430 ifFamInst = mb_family })
431 = bindIfaceTyVars_AT tv_bndrs $ \ tyvars -> do
432 { tc_name <- lookupIfaceTop occ_name
433 ; tycon <- fixM ( \ tycon -> do
434 { stupid_theta <- tcIfaceCtxt ctxt
435 ; mb_fam_inst <- tcFamInst mb_family
436 ; cons <- tcIfaceDataCons tc_name tycon tyvars rdr_cons
437 ; buildAlgTyCon tc_name tyvars stupid_theta
438 cons is_rec want_generic gadt_syn mb_fam_inst
440 ; traceIf (text "tcIfaceDecl4" <+> ppr tycon)
441 ; return (ATyCon tycon) }
443 tcIfaceDecl _ (IfaceSyn {ifName = occ_name, ifTyVars = tv_bndrs,
444 ifSynRhs = mb_rhs_ty,
445 ifSynKind = kind, ifFamInst = mb_family})
446 = bindIfaceTyVars_AT tv_bndrs $ \ tyvars -> do
447 { tc_name <- lookupIfaceTop occ_name
448 ; rhs_kind <- tcIfaceType kind -- Note [Synonym kind loop]
449 ; ~(rhs, fam) <- forkM (mk_doc tc_name) $
450 do { rhs <- tc_syn_rhs rhs_kind mb_rhs_ty
451 ; fam <- tcFamInst mb_family
452 ; return (rhs, fam) }
453 ; tycon <- buildSynTyCon tc_name tyvars rhs rhs_kind fam
454 ; return $ ATyCon tycon
457 mk_doc n = ptext (sLit "Type syonym") <+> ppr n
458 tc_syn_rhs kind Nothing = return (OpenSynTyCon kind Nothing)
459 tc_syn_rhs _ (Just ty) = do { rhs_ty <- tcIfaceType ty
460 ; return (SynonymTyCon rhs_ty) }
462 tcIfaceDecl ignore_prags
463 (IfaceClass {ifCtxt = rdr_ctxt, ifName = occ_name,
464 ifTyVars = tv_bndrs, ifFDs = rdr_fds,
465 ifATs = rdr_ats, ifSigs = rdr_sigs,
467 -- ToDo: in hs-boot files we should really treat abstract classes specially,
468 -- as we do abstract tycons
469 = bindIfaceTyVars tv_bndrs $ \ tyvars -> do
470 { cls_name <- lookupIfaceTop occ_name
471 ; ctxt <- tcIfaceCtxt rdr_ctxt
472 ; sigs <- mapM tc_sig rdr_sigs
473 ; fds <- mapM tc_fd rdr_fds
474 ; ats' <- mapM (tcIfaceDecl ignore_prags) rdr_ats
475 ; let ats = map (setAssocFamilyPermutation tyvars) ats'
476 ; cls <- buildClass ignore_prags cls_name tyvars ctxt fds ats sigs tc_isrec
477 ; return (AClass cls) }
479 tc_sig (IfaceClassOp occ dm rdr_ty)
480 = do { op_name <- lookupIfaceTop occ
481 ; op_ty <- forkM (mk_doc op_name rdr_ty) (tcIfaceType rdr_ty)
482 -- Must be done lazily for just the same reason as the
483 -- type of a data con; to avoid sucking in types that
484 -- it mentions unless it's necessray to do so
485 ; return (op_name, dm, op_ty) }
487 mk_doc op_name op_ty = ptext (sLit "Class op") <+> sep [ppr op_name, ppr op_ty]
489 tc_fd (tvs1, tvs2) = do { tvs1' <- mapM tcIfaceTyVar tvs1
490 ; tvs2' <- mapM tcIfaceTyVar tvs2
491 ; return (tvs1', tvs2') }
493 tcIfaceDecl _ (IfaceForeign {ifName = rdr_name, ifExtName = ext_name})
494 = do { name <- lookupIfaceTop rdr_name
495 ; return (ATyCon (mkForeignTyCon name ext_name
498 tcFamInst :: Maybe (IfaceTyCon, [IfaceType]) -> IfL (Maybe (TyCon, [Type]))
499 tcFamInst Nothing = return Nothing
500 tcFamInst (Just (fam, tys)) = do { famTyCon <- tcIfaceTyCon fam
501 ; insttys <- mapM tcIfaceType tys
502 ; return $ Just (famTyCon, insttys) }
504 tcIfaceDataCons :: Name -> TyCon -> [TyVar] -> IfaceConDecls -> IfL AlgTyConRhs
505 tcIfaceDataCons tycon_name tycon _ if_cons
507 IfAbstractTyCon -> return mkAbstractTyConRhs
508 IfOpenDataTyCon -> return mkOpenDataTyConRhs
509 IfDataTyCon cons -> do { data_cons <- mapM tc_con_decl cons
510 ; return (mkDataTyConRhs data_cons) }
511 IfNewTyCon con -> do { data_con <- tc_con_decl con
512 ; mkNewTyConRhs tycon_name tycon data_con }
514 tc_con_decl (IfCon { ifConInfix = is_infix,
515 ifConUnivTvs = univ_tvs, ifConExTvs = ex_tvs,
516 ifConOcc = occ, ifConCtxt = ctxt, ifConEqSpec = spec,
517 ifConArgTys = args, ifConFields = field_lbls,
518 ifConStricts = stricts})
519 = bindIfaceTyVars univ_tvs $ \ univ_tyvars -> do
520 bindIfaceTyVars ex_tvs $ \ ex_tyvars -> do
521 { name <- lookupIfaceTop occ
522 ; eq_spec <- tcIfaceEqSpec spec
523 ; theta <- tcIfaceCtxt ctxt -- Laziness seems not worth the bother here
524 -- At one stage I thought that this context checking *had*
525 -- to be lazy, because of possible mutual recursion between the
526 -- type and the classe:
528 -- class Real a where { toRat :: a -> Ratio Integer }
529 -- data (Real a) => Ratio a = ...
530 -- But now I think that the laziness in checking class ops breaks
531 -- the loop, so no laziness needed
533 -- Read the argument types, but lazily to avoid faulting in
534 -- the component types unless they are really needed
535 ; arg_tys <- forkM (mk_doc name) (mapM tcIfaceType args)
536 ; lbl_names <- mapM lookupIfaceTop field_lbls
538 -- Remember, tycon is the representation tycon
539 ; let orig_res_ty = mkFamilyTyConApp tycon
540 (substTyVars (mkTopTvSubst eq_spec) univ_tyvars)
542 ; buildDataCon name is_infix {- Not infix -}
544 univ_tyvars ex_tyvars
546 arg_tys orig_res_ty tycon
548 mk_doc con_name = ptext (sLit "Constructor") <+> ppr con_name
550 tcIfaceEqSpec :: [(OccName, IfaceType)] -> IfL [(TyVar, Type)]
554 do_item (occ, if_ty) = do { tv <- tcIfaceTyVar (occNameFS occ)
555 ; ty <- tcIfaceType if_ty
559 Note [Synonym kind loop]
560 ~~~~~~~~~~~~~~~~~~~~~~~~
561 Notice that we eagerly grab the *kind* from the interface file, but
562 build a forkM thunk for the *rhs* (and family stuff). To see why,
563 consider this (Trac #2412)
565 M.hs: module M where { import X; data T = MkT S }
566 X.hs: module X where { import {-# SOURCE #-} M; type S = T }
567 M.hs-boot: module M where { data T }
569 When kind-checking M.hs we need S's kind. But we do not want to
570 find S's kind from (typeKind S-rhs), because we don't want to look at
571 S-rhs yet! Since S is imported from X.hi, S gets just one chance to
572 be defined, and we must not do that until we've finished with M.T.
574 Solution: record S's kind in the interface file; now we can safely
577 %************************************************************************
581 %************************************************************************
584 tcIfaceInst :: IfaceInst -> IfL Instance
585 tcIfaceInst (IfaceInst { ifDFun = dfun_occ, ifOFlag = oflag,
586 ifInstCls = cls, ifInstTys = mb_tcs })
587 = do { dfun <- forkM (ptext (sLit "Dict fun") <+> ppr dfun_occ) $
588 tcIfaceExtId dfun_occ
589 ; let mb_tcs' = map (fmap ifaceTyConName) mb_tcs
590 ; return (mkImportedInstance cls mb_tcs' dfun oflag) }
592 tcIfaceFamInst :: IfaceFamInst -> IfL FamInst
593 tcIfaceFamInst (IfaceFamInst { ifFamInstTyCon = tycon,
594 ifFamInstFam = fam, ifFamInstTys = mb_tcs })
595 -- { tycon' <- forkM (ptext (sLit "Inst tycon") <+> ppr tycon) $
596 -- the above line doesn't work, but this below does => CPP in Haskell = evil!
597 = do tycon' <- forkM (text ("Inst tycon") <+> ppr tycon) $
599 let mb_tcs' = map (fmap ifaceTyConName) mb_tcs
600 return (mkImportedFamInst fam mb_tcs' tycon')
604 %************************************************************************
608 %************************************************************************
610 We move a IfaceRule from eps_rules to eps_rule_base when all its LHS free vars
611 are in the type environment. However, remember that typechecking a Rule may
612 (as a side effect) augment the type envt, and so we may need to iterate the process.
615 tcIfaceRules :: Bool -- True <=> ignore rules
618 tcIfaceRules ignore_prags if_rules
619 | ignore_prags = return []
620 | otherwise = mapM tcIfaceRule if_rules
622 tcIfaceRule :: IfaceRule -> IfL CoreRule
623 tcIfaceRule (IfaceRule {ifRuleName = name, ifActivation = act, ifRuleBndrs = bndrs,
624 ifRuleHead = fn, ifRuleArgs = args, ifRuleRhs = rhs })
625 = do { ~(bndrs', args', rhs') <-
626 -- Typecheck the payload lazily, in the hope it'll never be looked at
627 forkM (ptext (sLit "Rule") <+> ftext name) $
628 bindIfaceBndrs bndrs $ \ bndrs' ->
629 do { args' <- mapM tcIfaceExpr args
630 ; rhs' <- tcIfaceExpr rhs
631 ; return (bndrs', args', rhs') }
632 ; let mb_tcs = map ifTopFreeName args
633 ; return (Rule { ru_name = name, ru_fn = fn, ru_act = act,
634 ru_bndrs = bndrs', ru_args = args',
637 ru_local = False }) } -- An imported RULE is never for a local Id
638 -- or, even if it is (module loop, perhaps)
639 -- we'll just leave it in the non-local set
641 -- This function *must* mirror exactly what Rules.topFreeName does
642 -- We could have stored the ru_rough field in the iface file
643 -- but that would be redundant, I think.
644 -- The only wrinkle is that we must not be deceived by
645 -- type syononyms at the top of a type arg. Since
646 -- we can't tell at this point, we are careful not
647 -- to write them out in coreRuleToIfaceRule
648 ifTopFreeName :: IfaceExpr -> Maybe Name
649 ifTopFreeName (IfaceType (IfaceTyConApp tc _ )) = Just (ifaceTyConName tc)
650 ifTopFreeName (IfaceApp f _) = ifTopFreeName f
651 ifTopFreeName (IfaceExt n) = Just n
652 ifTopFreeName _ = Nothing
656 %************************************************************************
660 %************************************************************************
663 tcIfaceAnnotations :: [IfaceAnnotation] -> IfL [Annotation]
664 tcIfaceAnnotations = mapM tcIfaceAnnotation
666 tcIfaceAnnotation :: IfaceAnnotation -> IfL Annotation
667 tcIfaceAnnotation (IfaceAnnotation target serialized) = do
668 target' <- tcIfaceAnnTarget target
669 return $ Annotation {
670 ann_target = target',
671 ann_value = serialized
674 tcIfaceAnnTarget :: IfaceAnnTarget -> IfL (AnnTarget Name)
675 tcIfaceAnnTarget (NamedTarget occ) = do
676 name <- lookupIfaceTop occ
677 return $ NamedTarget name
678 tcIfaceAnnTarget (ModuleTarget mod) = do
679 return $ ModuleTarget mod
684 %************************************************************************
686 Vectorisation information
688 %************************************************************************
691 tcIfaceVectInfo :: Module -> TypeEnv -> IfaceVectInfo -> IfL VectInfo
692 tcIfaceVectInfo mod typeEnv (IfaceVectInfo
693 { ifaceVectInfoVar = vars
694 , ifaceVectInfoTyCon = tycons
695 , ifaceVectInfoTyConReuse = tyconsReuse
697 = do { vVars <- mapM vectVarMapping vars
698 ; tyConRes1 <- mapM vectTyConMapping tycons
699 ; tyConRes2 <- mapM vectTyConReuseMapping tyconsReuse
700 ; let (vTyCons, vDataCons, vPAs, vIsos) = unzip4 (tyConRes1 ++ tyConRes2)
702 { vectInfoVar = mkVarEnv vVars
703 , vectInfoTyCon = mkNameEnv vTyCons
704 , vectInfoDataCon = mkNameEnv (concat vDataCons)
705 , vectInfoPADFun = mkNameEnv vPAs
706 , vectInfoIso = mkNameEnv vIsos
711 = do { vName <- lookupOrig mod (mkVectOcc (nameOccName name))
712 ; let { var = lookupVar name
713 ; vVar = lookupVar vName
715 ; return (var, (var, vVar))
717 vectTyConMapping name
718 = do { vName <- lookupOrig mod (mkVectTyConOcc (nameOccName name))
719 ; paName <- lookupOrig mod (mkPADFunOcc (nameOccName name))
720 ; isoName <- lookupOrig mod (mkVectIsoOcc (nameOccName name))
721 ; let { tycon = lookupTyCon name
722 ; vTycon = lookupTyCon vName
723 ; paTycon = lookupVar paName
724 ; isoTycon = lookupVar isoName
726 ; vDataCons <- mapM vectDataConMapping (tyConDataCons tycon)
727 ; return ((name, (tycon, vTycon)), -- (T, T_v)
728 vDataCons, -- list of (Ci, Ci_v)
729 (vName, (vTycon, paTycon)), -- (T_v, paT)
730 (name, (tycon, isoTycon))) -- (T, isoT)
732 vectTyConReuseMapping name
733 = do { paName <- lookupOrig mod (mkPADFunOcc (nameOccName name))
734 ; isoName <- lookupOrig mod (mkVectIsoOcc (nameOccName name))
735 ; let { tycon = lookupTyCon name
736 ; paTycon = lookupVar paName
737 ; isoTycon = lookupVar isoName
738 ; vDataCons = [ (dataConName dc, (dc, dc))
739 | dc <- tyConDataCons tycon]
741 ; return ((name, (tycon, tycon)), -- (T, T)
742 vDataCons, -- list of (Ci, Ci)
743 (name, (tycon, paTycon)), -- (T, paT)
744 (name, (tycon, isoTycon))) -- (T, isoT)
746 vectDataConMapping datacon
747 = do { let name = dataConName datacon
748 ; vName <- lookupOrig mod (mkVectDataConOcc (nameOccName name))
749 ; let vDataCon = lookupDataCon vName
750 ; return (name, (datacon, vDataCon))
753 lookupVar name = case lookupTypeEnv typeEnv name of
754 Just (AnId var) -> var
756 panic "TcIface.tcIfaceVectInfo: not an id"
758 panic "TcIface.tcIfaceVectInfo: unknown name"
759 lookupTyCon name = case lookupTypeEnv typeEnv name of
760 Just (ATyCon tc) -> tc
762 panic "TcIface.tcIfaceVectInfo: not a tycon"
764 panic "TcIface.tcIfaceVectInfo: unknown name"
765 lookupDataCon name = case lookupTypeEnv typeEnv name of
766 Just (ADataCon dc) -> dc
768 panic "TcIface.tcIfaceVectInfo: not a datacon"
770 panic "TcIface.tcIfaceVectInfo: unknown name"
773 %************************************************************************
777 %************************************************************************
780 tcIfaceType :: IfaceType -> IfL Type
781 tcIfaceType (IfaceTyVar n) = do { tv <- tcIfaceTyVar n; return (TyVarTy tv) }
782 tcIfaceType (IfaceAppTy t1 t2) = do { t1' <- tcIfaceType t1; t2' <- tcIfaceType t2; return (AppTy t1' t2') }
783 tcIfaceType (IfaceFunTy t1 t2) = do { t1' <- tcIfaceType t1; t2' <- tcIfaceType t2; return (FunTy t1' t2') }
784 tcIfaceType (IfaceTyConApp tc ts) = do { tc' <- tcIfaceTyCon tc; ts' <- tcIfaceTypes ts; return (mkTyConApp tc' ts') }
785 tcIfaceType (IfaceForAllTy tv t) = bindIfaceTyVar tv $ \ tv' -> do { t' <- tcIfaceType t; return (ForAllTy tv' t') }
786 tcIfaceType (IfacePredTy st) = do { st' <- tcIfacePredType st; return (PredTy st') }
788 tcIfaceTypes :: [IfaceType] -> IfL [Type]
789 tcIfaceTypes tys = mapM tcIfaceType tys
791 -----------------------------------------
792 tcIfacePredType :: IfacePredType -> IfL PredType
793 tcIfacePredType (IfaceClassP cls ts) = do { cls' <- tcIfaceClass cls; ts' <- tcIfaceTypes ts; return (ClassP cls' ts') }
794 tcIfacePredType (IfaceIParam ip t) = do { ip' <- newIPName ip; t' <- tcIfaceType t; return (IParam ip' t') }
795 tcIfacePredType (IfaceEqPred t1 t2) = do { t1' <- tcIfaceType t1; t2' <- tcIfaceType t2; return (EqPred t1' t2') }
797 -----------------------------------------
798 tcIfaceCtxt :: IfaceContext -> IfL ThetaType
799 tcIfaceCtxt sts = mapM tcIfacePredType sts
803 %************************************************************************
807 %************************************************************************
810 tcIfaceExpr :: IfaceExpr -> IfL CoreExpr
811 tcIfaceExpr (IfaceType ty)
812 = Type <$> tcIfaceType ty
814 tcIfaceExpr (IfaceLcl name)
815 = Var <$> tcIfaceLclId name
817 tcIfaceExpr (IfaceTick modName tickNo)
818 = Var <$> tcIfaceTick modName tickNo
820 tcIfaceExpr (IfaceExt gbl)
821 = Var <$> tcIfaceExtId gbl
823 tcIfaceExpr (IfaceLit lit)
826 tcIfaceExpr (IfaceFCall cc ty) = do
827 ty' <- tcIfaceType ty
829 return (Var (mkFCallId u cc ty'))
831 tcIfaceExpr (IfaceTuple boxity args) = do
832 args' <- mapM tcIfaceExpr args
833 -- Put the missing type arguments back in
834 let con_args = map (Type . exprType) args' ++ args'
835 return (mkApps (Var con_id) con_args)
838 con_id = dataConWorkId (tupleCon boxity arity)
841 tcIfaceExpr (IfaceLam bndr body)
842 = bindIfaceBndr bndr $ \bndr' ->
843 Lam bndr' <$> tcIfaceExpr body
845 tcIfaceExpr (IfaceApp fun arg)
846 = App <$> tcIfaceExpr fun <*> tcIfaceExpr arg
848 tcIfaceExpr (IfaceCase scrut case_bndr ty alts) = do
849 scrut' <- tcIfaceExpr scrut
850 case_bndr_name <- newIfaceName (mkVarOccFS case_bndr)
852 scrut_ty = exprType scrut'
853 case_bndr' = mkLocalId case_bndr_name scrut_ty
854 tc_app = splitTyConApp scrut_ty
855 -- NB: Won't always succeed (polymoprhic case)
856 -- but won't be demanded in those cases
857 -- NB: not tcSplitTyConApp; we are looking at Core here
858 -- look through non-rec newtypes to find the tycon that
859 -- corresponds to the datacon in this case alternative
861 extendIfaceIdEnv [case_bndr'] $ do
862 alts' <- mapM (tcIfaceAlt scrut' tc_app) alts
863 ty' <- tcIfaceType ty
864 return (Case scrut' case_bndr' ty' alts')
866 tcIfaceExpr (IfaceLet (IfaceNonRec bndr rhs) body) = do
867 rhs' <- tcIfaceExpr rhs
868 id <- tcIfaceLetBndr bndr
869 body' <- extendIfaceIdEnv [id] (tcIfaceExpr body)
870 return (Let (NonRec id rhs') body')
872 tcIfaceExpr (IfaceLet (IfaceRec pairs) body) = do
873 ids <- mapM tcIfaceLetBndr bndrs
874 extendIfaceIdEnv ids $ do
875 rhss' <- mapM tcIfaceExpr rhss
876 body' <- tcIfaceExpr body
877 return (Let (Rec (ids `zip` rhss')) body')
879 (bndrs, rhss) = unzip pairs
881 tcIfaceExpr (IfaceCast expr co) = do
882 expr' <- tcIfaceExpr expr
883 co' <- tcIfaceType co
884 return (Cast expr' co')
886 tcIfaceExpr (IfaceNote note expr) = do
887 expr' <- tcIfaceExpr expr
889 IfaceInlineMe -> return (Note InlineMe expr')
890 IfaceSCC cc -> return (Note (SCC cc) expr')
891 IfaceCoreNote n -> return (Note (CoreNote n) expr')
893 -------------------------
894 tcIfaceAlt :: CoreExpr -> (TyCon, [Type])
895 -> (IfaceConAlt, [FastString], IfaceExpr)
896 -> IfL (AltCon, [TyVar], CoreExpr)
897 tcIfaceAlt _ _ (IfaceDefault, names, rhs)
898 = ASSERT( null names ) do
899 rhs' <- tcIfaceExpr rhs
900 return (DEFAULT, [], rhs')
902 tcIfaceAlt _ _ (IfaceLitAlt lit, names, rhs)
903 = ASSERT( null names ) do
904 rhs' <- tcIfaceExpr rhs
905 return (LitAlt lit, [], rhs')
907 -- A case alternative is made quite a bit more complicated
908 -- by the fact that we omit type annotations because we can
909 -- work them out. True enough, but its not that easy!
910 tcIfaceAlt scrut (tycon, inst_tys) (IfaceDataAlt data_occ, arg_strs, rhs)
911 = do { con <- tcIfaceDataCon data_occ
912 ; when (debugIsOn && not (con `elem` tyConDataCons tycon))
913 (failIfM (ppr scrut $$ ppr con $$ ppr tycon $$ ppr (tyConDataCons tycon)))
914 ; tcIfaceDataAlt con inst_tys arg_strs rhs }
916 tcIfaceAlt _ (tycon, inst_tys) (IfaceTupleAlt _boxity, arg_occs, rhs)
917 = ASSERT( isTupleTyCon tycon )
918 do { let [data_con] = tyConDataCons tycon
919 ; tcIfaceDataAlt data_con inst_tys arg_occs rhs }
921 tcIfaceDataAlt :: DataCon -> [Type] -> [FastString] -> IfaceExpr
922 -> IfL (AltCon, [TyVar], CoreExpr)
923 tcIfaceDataAlt con inst_tys arg_strs rhs
924 = do { us <- newUniqueSupply
925 ; let uniqs = uniqsFromSupply us
926 ; let (ex_tvs, co_tvs, arg_ids)
927 = dataConRepFSInstPat arg_strs uniqs con inst_tys
928 all_tvs = ex_tvs ++ co_tvs
930 ; rhs' <- extendIfaceTyVarEnv all_tvs $
931 extendIfaceIdEnv arg_ids $
933 ; return (DataAlt con, all_tvs ++ arg_ids, rhs') }
938 tcExtCoreBindings :: [IfaceBinding] -> IfL [CoreBind] -- Used for external core
939 tcExtCoreBindings [] = return []
940 tcExtCoreBindings (b:bs) = do_one b (tcExtCoreBindings bs)
942 do_one :: IfaceBinding -> IfL [CoreBind] -> IfL [CoreBind]
943 do_one (IfaceNonRec bndr rhs) thing_inside
944 = do { rhs' <- tcIfaceExpr rhs
945 ; bndr' <- newExtCoreBndr bndr
946 ; extendIfaceIdEnv [bndr'] $ do
947 { core_binds <- thing_inside
948 ; return (NonRec bndr' rhs' : core_binds) }}
950 do_one (IfaceRec pairs) thing_inside
951 = do { bndrs' <- mapM newExtCoreBndr bndrs
952 ; extendIfaceIdEnv bndrs' $ do
953 { rhss' <- mapM tcIfaceExpr rhss
954 ; core_binds <- thing_inside
955 ; return (Rec (bndrs' `zip` rhss') : core_binds) }}
957 (bndrs,rhss) = unzip pairs
961 %************************************************************************
965 %************************************************************************
968 tcIdDetails :: IfaceIdDetails -> IfL IdDetails
969 tcIdDetails IfVanillaId = return VanillaId
970 tcIdDetails IfDFunId = return DFunId
971 tcIdDetails (IfRecSelId tc naughty)
972 = do { tc' <- tcIfaceTyCon tc
973 ; return (RecSelId { sel_tycon = tc', sel_naughty = naughty }) }
975 tcIdInfo :: Bool -> Name -> Type -> IfaceIdInfo -> IfL IdInfo
976 tcIdInfo ignore_prags name ty info
977 | ignore_prags = return vanillaIdInfo
978 | otherwise = case info of
979 NoInfo -> return vanillaIdInfo
980 HasInfo info -> foldlM tcPrag init_info info
982 -- Set the CgInfo to something sensible but uninformative before
983 -- we start; default assumption is that it has CAFs
984 init_info = vanillaIdInfo
986 tcPrag :: IdInfo -> IfaceInfoItem -> IfL IdInfo
987 tcPrag info HsNoCafRefs = return (info `setCafInfo` NoCafRefs)
988 tcPrag info (HsArity arity) = return (info `setArityInfo` arity)
989 tcPrag info (HsStrictness str) = return (info `setAllStrictnessInfo` Just str)
991 -- The next two are lazy, so they don't transitively suck stuff in
992 tcPrag info (HsWorker nm arity) = tcWorkerInfo ty info nm arity
993 tcPrag info (HsInline inline_prag) = return (info `setInlinePragInfo` inline_prag)
994 tcPrag info (HsUnfold expr) = do
995 maybe_expr' <- tcPragExpr name expr
997 -- maybe_expr' doesn't get looked at if the unfolding
998 -- is never inspected; so the typecheck doesn't even happen
999 unfold_info = case maybe_expr' of
1000 Nothing -> noUnfolding
1001 Just expr' -> mkTopUnfolding expr'
1002 return (info `setUnfoldingInfoLazily` unfold_info)
1006 tcWorkerInfo :: Type -> IdInfo -> Name -> Arity -> IfL IdInfo
1007 tcWorkerInfo ty info wkr arity
1008 = do { mb_wkr_id <- forkM_maybe doc (tcIfaceExtId wkr)
1010 -- We return without testing maybe_wkr_id, but as soon as info is
1011 -- looked at we will test it. That's ok, because its outside the
1012 -- knot; and there seems no big reason to further defer the
1013 -- tcIfaceId lookup. (Contrast with tcPragExpr, where postponing walking
1014 -- over the unfolding until it's actually used does seem worth while.)
1015 ; us <- newUniqueSupply
1017 ; return (case mb_wkr_id of
1019 Just wkr_id -> add_wkr_info us wkr_id info) }
1021 doc = text "Worker for" <+> ppr wkr
1022 add_wkr_info us wkr_id info
1023 = info `setUnfoldingInfoLazily` mk_unfolding us wkr_id
1024 `setWorkerInfo` HasWorker wkr_id arity
1026 mk_unfolding us wkr_id = mkTopUnfolding (initUs_ us (mkWrapper ty strict_sig) wkr_id)
1028 -- We are relying here on strictness info always appearing
1029 -- before worker info, fingers crossed ....
1030 strict_sig = case newStrictnessInfo info of
1032 Nothing -> pprPanic "Worker info but no strictness for" (ppr wkr)
1035 For unfoldings we try to do the job lazily, so that we never type check
1036 an unfolding that isn't going to be looked at.
1039 tcPragExpr :: Name -> IfaceExpr -> IfL (Maybe CoreExpr)
1040 tcPragExpr name expr
1041 = forkM_maybe doc $ do
1042 core_expr' <- tcIfaceExpr expr
1044 -- Check for type consistency in the unfolding
1045 ifOptM Opt_DoCoreLinting $ do
1046 in_scope <- get_in_scope_ids
1047 case lintUnfolding noSrcLoc in_scope core_expr' of
1048 Nothing -> return ()
1049 Just fail_msg -> pprPanic "Iface Lint failure" (hang doc 2 fail_msg)
1053 doc = text "Unfolding of" <+> ppr name
1054 get_in_scope_ids -- Urgh; but just for linting
1056 do { env <- getGblEnv
1057 ; case if_rec_types env of {
1058 Nothing -> return [] ;
1059 Just (_, get_env) -> do
1060 { type_env <- get_env
1061 ; return (typeEnvIds type_env) }}}
1066 %************************************************************************
1068 Getting from Names to TyThings
1070 %************************************************************************
1073 tcIfaceGlobal :: Name -> IfL TyThing
1075 | Just thing <- wiredInNameTyThing_maybe name
1076 -- Wired-in things include TyCons, DataCons, and Ids
1077 = do { ifCheckWiredInThing thing; return thing }
1079 = do { env <- getGblEnv
1080 ; case if_rec_types env of { -- Note [Tying the knot]
1081 Just (mod, get_type_env)
1082 | nameIsLocalOrFrom mod name
1083 -> do -- It's defined in the module being compiled
1084 { type_env <- setLclEnv () get_type_env -- yuk
1085 ; case lookupNameEnv type_env name of
1086 Just thing -> return thing
1087 Nothing -> pprPanic "tcIfaceGlobal (local): not found:"
1088 (ppr name $$ ppr type_env) }
1092 { hsc_env <- getTopEnv
1093 ; mb_thing <- liftIO (lookupTypeHscEnv hsc_env name)
1094 ; case mb_thing of {
1095 Just thing -> return thing ;
1098 { mb_thing <- importDecl name -- It's imported; go get it
1100 Failed err -> failIfM err
1101 Succeeded thing -> return thing
1104 -- Note [Tying the knot]
1105 -- ~~~~~~~~~~~~~~~~~~~~~
1106 -- The if_rec_types field is used in two situations:
1108 -- a) Compiling M.hs, which indiretly imports Foo.hi, which mentions M.T
1109 -- Then we look up M.T in M's type environment, which is splatted into if_rec_types
1110 -- after we've built M's type envt.
1112 -- b) In ghc --make, during the upsweep, we encounter M.hs, whose interface M.hi
1113 -- is up to date. So we call typecheckIface on M.hi. This splats M.T into
1114 -- if_rec_types so that the (lazily typechecked) decls see all the other decls
1116 -- In case (b) it's important to do the if_rec_types check *before* looking in the HPT
1117 -- Because if M.hs also has M.hs-boot, M.T will *already be* in the HPT, but in its
1118 -- emasculated form (e.g. lacking data constructors).
1120 tcIfaceTyCon :: IfaceTyCon -> IfL TyCon
1121 tcIfaceTyCon IfaceIntTc = tcWiredInTyCon intTyCon
1122 tcIfaceTyCon IfaceBoolTc = tcWiredInTyCon boolTyCon
1123 tcIfaceTyCon IfaceCharTc = tcWiredInTyCon charTyCon
1124 tcIfaceTyCon IfaceListTc = tcWiredInTyCon listTyCon
1125 tcIfaceTyCon IfacePArrTc = tcWiredInTyCon parrTyCon
1126 tcIfaceTyCon (IfaceTupTc bx ar) = tcWiredInTyCon (tupleTyCon bx ar)
1127 tcIfaceTyCon (IfaceTc name) = do { thing <- tcIfaceGlobal name
1128 ; return (check_tc (tyThingTyCon thing)) }
1131 | debugIsOn = case toIfaceTyCon tc of
1133 _ -> pprTrace "check_tc" (ppr tc) tc
1135 -- we should be okay just returning Kind constructors without extra loading
1136 tcIfaceTyCon IfaceLiftedTypeKindTc = return liftedTypeKindTyCon
1137 tcIfaceTyCon IfaceOpenTypeKindTc = return openTypeKindTyCon
1138 tcIfaceTyCon IfaceUnliftedTypeKindTc = return unliftedTypeKindTyCon
1139 tcIfaceTyCon IfaceArgTypeKindTc = return argTypeKindTyCon
1140 tcIfaceTyCon IfaceUbxTupleKindTc = return ubxTupleKindTyCon
1142 -- Even though we are in an interface file, we want to make
1143 -- sure the instances and RULES of this tycon are loaded
1144 -- Imagine: f :: Double -> Double
1145 tcWiredInTyCon :: TyCon -> IfL TyCon
1146 tcWiredInTyCon tc = do { ifCheckWiredInThing (ATyCon tc)
1149 tcIfaceClass :: Name -> IfL Class
1150 tcIfaceClass name = do { thing <- tcIfaceGlobal name
1151 ; return (tyThingClass thing) }
1153 tcIfaceDataCon :: Name -> IfL DataCon
1154 tcIfaceDataCon name = do { thing <- tcIfaceGlobal name
1156 ADataCon dc -> return dc
1157 _ -> pprPanic "tcIfaceExtDC" (ppr name$$ ppr thing) }
1159 tcIfaceExtId :: Name -> IfL Id
1160 tcIfaceExtId name = do { thing <- tcIfaceGlobal name
1162 AnId id -> return id
1163 _ -> pprPanic "tcIfaceExtId" (ppr name$$ ppr thing) }
1166 %************************************************************************
1170 %************************************************************************
1173 bindIfaceBndr :: IfaceBndr -> (CoreBndr -> IfL a) -> IfL a
1174 bindIfaceBndr (IfaceIdBndr (fs, ty)) thing_inside
1175 = do { name <- newIfaceName (mkVarOccFS fs)
1176 ; ty' <- tcIfaceType ty
1177 ; let id = mkLocalId name ty'
1178 ; extendIfaceIdEnv [id] (thing_inside id) }
1179 bindIfaceBndr (IfaceTvBndr bndr) thing_inside
1180 = bindIfaceTyVar bndr thing_inside
1182 bindIfaceBndrs :: [IfaceBndr] -> ([CoreBndr] -> IfL a) -> IfL a
1183 bindIfaceBndrs [] thing_inside = thing_inside []
1184 bindIfaceBndrs (b:bs) thing_inside
1185 = bindIfaceBndr b $ \ b' ->
1186 bindIfaceBndrs bs $ \ bs' ->
1187 thing_inside (b':bs')
1190 -----------------------
1191 tcIfaceLetBndr :: IfaceLetBndr -> IfL Id
1192 tcIfaceLetBndr (IfLetBndr fs ty info)
1193 = do { name <- newIfaceName (mkVarOccFS fs)
1194 ; ty' <- tcIfaceType ty
1196 NoInfo -> return (mkLocalId name ty')
1197 HasInfo i -> return (mkLocalIdWithInfo name ty' (tc_info i)) }
1199 -- Similar to tcIdInfo, but much simpler
1200 tc_info [] = vanillaIdInfo
1201 tc_info (HsInline p : i) = tc_info i `setInlinePragInfo` p
1202 tc_info (HsArity a : i) = tc_info i `setArityInfo` a
1203 tc_info (HsStrictness s : i) = tc_info i `setAllStrictnessInfo` Just s
1204 tc_info (other : i) = pprTrace "tcIfaceLetBndr: discarding unexpected IdInfo"
1205 (ppr other) (tc_info i)
1207 -----------------------
1208 newExtCoreBndr :: IfaceLetBndr -> IfL Id
1209 newExtCoreBndr (IfLetBndr var ty _) -- Ignoring IdInfo for now
1210 = do { mod <- getIfModule
1211 ; name <- newGlobalBinder mod (mkVarOccFS var) noSrcSpan
1212 ; ty' <- tcIfaceType ty
1213 ; return (mkLocalId name ty') }
1215 -----------------------
1216 bindIfaceTyVar :: IfaceTvBndr -> (TyVar -> IfL a) -> IfL a
1217 bindIfaceTyVar (occ,kind) thing_inside
1218 = do { name <- newIfaceName (mkTyVarOccFS occ)
1219 ; tyvar <- mk_iface_tyvar name kind
1220 ; extendIfaceTyVarEnv [tyvar] (thing_inside tyvar) }
1222 bindIfaceTyVars :: [IfaceTvBndr] -> ([TyVar] -> IfL a) -> IfL a
1223 bindIfaceTyVars bndrs thing_inside
1224 = do { names <- newIfaceNames (map mkTyVarOccFS occs)
1225 ; tyvars <- zipWithM mk_iface_tyvar names kinds
1226 ; extendIfaceTyVarEnv tyvars (thing_inside tyvars) }
1228 (occs,kinds) = unzip bndrs
1230 mk_iface_tyvar :: Name -> IfaceKind -> IfL TyVar
1231 mk_iface_tyvar name ifKind
1232 = do { kind <- tcIfaceType ifKind
1233 ; if isCoercionKind kind then
1234 return (Var.mkCoVar name kind)
1236 return (Var.mkTyVar name kind) }
1238 bindIfaceTyVars_AT :: [IfaceTvBndr] -> ([TyVar] -> IfL a) -> IfL a
1239 -- Used for type variable in nested associated data/type declarations
1240 -- where some of the type variables are already in scope
1241 -- class C a where { data T a b }
1242 -- Here 'a' is in scope when we look at the 'data T'
1243 bindIfaceTyVars_AT [] thing_inside
1245 bindIfaceTyVars_AT (b@(tv_occ,_) : bs) thing_inside
1246 = bindIfaceTyVars_AT bs $ \ bs' ->
1247 do { mb_tv <- lookupIfaceTyVar tv_occ
1249 Just b' -> thing_inside (b':bs')
1250 Nothing -> bindIfaceTyVar b $ \ b' ->
1251 thing_inside (b':bs') }