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"
41 import TysPrim ( anyTyConOfKind )
43 import BasicTypes ( nonRuleLoopBreaker )
48 import OccurAnal ( occurAnalyseExpr )
49 import Demand ( isBottomingSig )
71 An IfaceDecl is populated with RdrNames, and these are not renamed to
72 Names before typechecking, because there should be no scope errors etc.
74 -- For (b) consider: f = \$(...h....)
75 -- where h is imported, and calls f via an hi-boot file.
76 -- This is bad! But it is not seen as a staging error, because h
77 -- is indeed imported. We don't want the type-checker to black-hole
78 -- when simplifying and compiling the splice!
80 -- Simple solution: discard any unfolding that mentions a variable
81 -- bound in this module (and hence not yet processed).
82 -- The discarding happens when forkM finds a type error.
84 %************************************************************************
86 %* tcImportDecl is the key function for "faulting in" *
89 %************************************************************************
91 The main idea is this. We are chugging along type-checking source code, and
92 find a reference to GHC.Base.map. We call tcLookupGlobal, which doesn't find
93 it in the EPS type envt. So it
95 2 gets the decl for GHC.Base.map
96 3 typechecks it via tcIfaceDecl
97 4 and adds it to the type env in the EPS
99 Note that DURING STEP 4, we may find that map's type mentions a type
100 constructor that also
102 Notice that for imported things we read the current version from the EPS
103 mutable variable. This is important in situations like
105 where the code that e1 expands to might import some defns that
106 also turn out to be needed by the code that e2 expands to.
109 tcImportDecl :: Name -> TcM TyThing
110 -- Entry point for *source-code* uses of importDecl
112 | Just thing <- wiredInNameTyThing_maybe name
113 = do { when (needWiredInHomeIface thing)
114 (initIfaceTcRn (loadWiredInHomeIface name))
115 -- See Note [Loading instances for wired-in things]
118 = do { traceIf (text "tcImportDecl" <+> ppr name)
119 ; mb_thing <- initIfaceTcRn (importDecl name)
121 Succeeded thing -> return thing
122 Failed err -> failWithTc err }
124 importDecl :: Name -> IfM lcl (MaybeErr Message TyThing)
125 -- Get the TyThing for this Name from an interface file
126 -- It's not a wired-in thing -- the caller caught that
128 = ASSERT( not (isWiredInName name) )
131 -- Load the interface, which should populate the PTE
132 ; mb_iface <- ASSERT2( isExternalName name, ppr name )
133 loadInterface nd_doc (nameModule name) ImportBySystem
135 Failed err_msg -> return (Failed err_msg) ;
138 -- Now look it up again; this time we should find it
140 ; case lookupTypeEnv (eps_PTE eps) name of
141 Just thing -> return (Succeeded thing)
142 Nothing -> return (Failed not_found_msg)
145 nd_doc = ptext (sLit "Need decl for") <+> ppr name
146 not_found_msg = hang (ptext (sLit "Can't find interface-file declaration for") <+>
147 pprNameSpace (occNameSpace (nameOccName name)) <+> ppr name)
148 2 (vcat [ptext (sLit "Probable cause: bug in .hi-boot file, or inconsistent .hi file"),
149 ptext (sLit "Use -ddump-if-trace to get an idea of which file caused the error")])
152 %************************************************************************
154 Checks for wired-in things
156 %************************************************************************
158 Note [Loading instances for wired-in things]
159 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
160 We need to make sure that we have at least *read* the interface files
161 for any module with an instance decl or RULE that we might want.
163 * If the instance decl is an orphan, we have a whole separate mechanism
166 * If the instance decl not an orphan, then the act of looking at the
167 TyCon or Class will force in the defining module for the
168 TyCon/Class, and hence the instance decl
170 * BUT, if the TyCon is a wired-in TyCon, we don't really need its interface;
171 but we must make sure we read its interface in case it has instances or
172 rules. That is what LoadIface.loadWiredInHomeInterface does. It's called
173 from TcIface.{tcImportDecl, checkWiredInTyCon, ifCheckWiredInThing}
175 * HOWEVER, only do this for TyCons. There are no wired-in Classes. There
176 are some wired-in Ids, but we don't want to load their interfaces. For
177 example, Control.Exception.Base.recSelError is wired in, but that module
178 is compiled late in the base library, and we don't want to force it to
179 load before it's been compiled!
181 All of this is done by the type checker. The renamer plays no role.
182 (It used to, but no longer.)
186 checkWiredInTyCon :: TyCon -> TcM ()
187 -- Ensure that the home module of the TyCon (and hence its instances)
188 -- are loaded. See Note [Loading instances for wired-in things]
189 -- It might not be a wired-in tycon (see the calls in TcUnify),
190 -- in which case this is a no-op.
192 | not (isWiredInName tc_name)
195 = do { mod <- getModule
196 ; ASSERT( isExternalName tc_name )
197 when (mod /= nameModule tc_name)
198 (initIfaceTcRn (loadWiredInHomeIface tc_name))
199 -- Don't look for (non-existent) Float.hi when
200 -- compiling Float.lhs, which mentions Float of course
201 -- A bit yukky to call initIfaceTcRn here
204 tc_name = tyConName tc
206 ifCheckWiredInThing :: TyThing -> IfL ()
207 -- Even though we are in an interface file, we want to make
208 -- sure the instances of a wired-in thing are loaded (imagine f :: Double -> Double)
209 -- Ditto want to ensure that RULES are loaded too
210 -- See Note [Loading instances for wired-in things]
211 ifCheckWiredInThing thing
212 = do { mod <- getIfModule
213 -- Check whether we are typechecking the interface for this
214 -- very module. E.g when compiling the base library in --make mode
215 -- we may typecheck GHC.Base.hi. At that point, GHC.Base is not in
216 -- the HPT, so without the test we'll demand-load it into the PIT!
217 -- C.f. the same test in checkWiredInTyCon above
218 ; let name = getName thing
219 ; ASSERT2( isExternalName name, ppr name )
220 when (needWiredInHomeIface thing && mod /= nameModule name)
221 (loadWiredInHomeIface name) }
223 needWiredInHomeIface :: TyThing -> Bool
224 -- Only for TyCons; see Note [Loading instances for wired-in things]
225 needWiredInHomeIface (ATyCon {}) = True
226 needWiredInHomeIface _ = False
229 %************************************************************************
231 Type-checking a complete interface
233 %************************************************************************
235 Suppose we discover we don't need to recompile. Then we must type
236 check the old interface file. This is a bit different to the
237 incremental type checking we do as we suck in interface files. Instead
238 we do things similarly as when we are typechecking source decls: we
239 bring into scope the type envt for the interface all at once, using a
240 knot. Remember, the decls aren't necessarily in dependency order --
241 and even if they were, the type decls might be mutually recursive.
244 typecheckIface :: ModIface -- Get the decls from here
245 -> TcRnIf gbl lcl ModDetails
247 = initIfaceTc iface $ \ tc_env_var -> do
248 -- The tc_env_var is freshly allocated, private to
249 -- type-checking this particular interface
250 { -- Get the right set of decls and rules. If we are compiling without -O
251 -- we discard pragmas before typechecking, so that we don't "see"
252 -- information that we shouldn't. From a versioning point of view
253 -- It's not actually *wrong* to do so, but in fact GHCi is unable
254 -- to handle unboxed tuples, so it must not see unfoldings.
255 ignore_prags <- doptM Opt_IgnoreInterfacePragmas
257 -- Typecheck the decls. This is done lazily, so that the knot-tying
258 -- within this single module work out right. In the If monad there is
259 -- no global envt for the current interface; instead, the knot is tied
260 -- through the if_rec_types field of IfGblEnv
261 ; names_w_things <- loadDecls ignore_prags (mi_decls iface)
262 ; let type_env = mkNameEnv names_w_things
263 ; writeMutVar tc_env_var type_env
265 -- Now do those rules, instances and annotations
266 ; insts <- mapM tcIfaceInst (mi_insts iface)
267 ; fam_insts <- mapM tcIfaceFamInst (mi_fam_insts iface)
268 ; rules <- tcIfaceRules ignore_prags (mi_rules iface)
269 ; anns <- tcIfaceAnnotations (mi_anns iface)
271 -- Vectorisation information
272 ; vect_info <- tcIfaceVectInfo (mi_module iface) type_env
276 ; exports <- ifaceExportNames (mi_exports iface)
279 ; traceIf (vcat [text "Finished typechecking interface for" <+> ppr (mi_module iface),
280 text "Type envt:" <+> ppr type_env])
281 ; return $ ModDetails { md_types = type_env
283 , md_fam_insts = fam_insts
286 , md_vect_info = vect_info
287 , md_exports = exports
293 %************************************************************************
295 Type and class declarations
297 %************************************************************************
300 tcHiBootIface :: HscSource -> Module -> TcRn ModDetails
301 -- Load the hi-boot iface for the module being compiled,
302 -- if it indeed exists in the transitive closure of imports
303 -- Return the ModDetails, empty if no hi-boot iface
304 tcHiBootIface hsc_src mod
305 | isHsBoot hsc_src -- Already compiling a hs-boot file
306 = return emptyModDetails
308 = do { traceIf (text "loadHiBootInterface" <+> ppr mod)
311 ; if not (isOneShot mode)
312 -- In --make and interactive mode, if this module has an hs-boot file
313 -- we'll have compiled it already, and it'll be in the HPT
315 -- We check wheher the interface is a *boot* interface.
316 -- It can happen (when using GHC from Visual Studio) that we
317 -- compile a module in TypecheckOnly mode, with a stable,
318 -- fully-populated HPT. In that case the boot interface isn't there
319 -- (it's been replaced by the mother module) so we can't check it.
320 -- And that's fine, because if M's ModInfo is in the HPT, then
321 -- it's been compiled once, and we don't need to check the boot iface
322 then do { hpt <- getHpt
323 ; case lookupUFM hpt (moduleName mod) of
324 Just info | mi_boot (hm_iface info)
325 -> return (hm_details info)
326 _ -> return emptyModDetails }
329 -- OK, so we're in one-shot mode.
330 -- In that case, we're read all the direct imports by now,
331 -- so eps_is_boot will record if any of our imports mention us by
332 -- way of hi-boot file
334 ; case lookupUFM (eps_is_boot eps) (moduleName mod) of {
335 Nothing -> return emptyModDetails ; -- The typical case
337 Just (_, False) -> failWithTc moduleLoop ;
338 -- Someone below us imported us!
339 -- This is a loop with no hi-boot in the way
341 Just (_mod, True) -> -- There's a hi-boot interface below us
343 do { read_result <- findAndReadIface
347 ; case read_result of
348 Failed err -> failWithTc (elaborate err)
349 Succeeded (iface, _path) -> typecheckIface iface
352 need = ptext (sLit "Need the hi-boot interface for") <+> ppr mod
353 <+> ptext (sLit "to compare against the Real Thing")
355 moduleLoop = ptext (sLit "Circular imports: module") <+> quotes (ppr mod)
356 <+> ptext (sLit "depends on itself")
358 elaborate err = hang (ptext (sLit "Could not find hi-boot interface for") <+>
359 quotes (ppr mod) <> colon) 4 err
363 %************************************************************************
365 Type and class declarations
367 %************************************************************************
369 When typechecking a data type decl, we *lazily* (via forkM) typecheck
370 the constructor argument types. This is in the hope that we may never
371 poke on those argument types, and hence may never need to load the
372 interface files for types mentioned in the arg types.
375 data Foo.S = MkS Baz.T
376 Mabye we can get away without even loading the interface for Baz!
378 This is not just a performance thing. Suppose we have
379 data Foo.S = MkS Baz.T
380 data Baz.T = MkT Foo.S
381 (in different interface files, of course).
382 Now, first we load and typecheck Foo.S, and add it to the type envt.
383 If we do explore MkS's argument, we'll load and typecheck Baz.T.
384 If we explore MkT's argument we'll find Foo.S already in the envt.
386 If we typechecked constructor args eagerly, when loading Foo.S we'd try to
387 typecheck the type Baz.T. So we'd fault in Baz.T... and then need Foo.S...
388 which isn't done yet.
390 All very cunning. However, there is a rather subtle gotcha which bit
391 me when developing this stuff. When we typecheck the decl for S, we
392 extend the type envt with S, MkS, and all its implicit Ids. Suppose
393 (a bug, but it happened) that the list of implicit Ids depended in
394 turn on the constructor arg types. Then the following sequence of
396 * we build a thunk <t> for the constructor arg tys
397 * we build a thunk for the extended type environment (depends on <t>)
398 * we write the extended type envt into the global EPS mutvar
400 Now we look something up in the type envt
402 * which reads the global type envt out of the global EPS mutvar
403 * but that depends in turn on <t>
405 It's subtle, because, it'd work fine if we typechecked the constructor args
406 eagerly -- they don't need the extended type envt. They just get the extended
407 type envt by accident, because they look at it later.
409 What this means is that the implicitTyThings MUST NOT DEPEND on any of
414 tcIfaceDecl :: Bool -- True <=> discard IdInfo on IfaceId bindings
417 tcIfaceDecl = tc_iface_decl NoParentTyCon
419 tc_iface_decl :: TyConParent -- For nested declarations
420 -> Bool -- True <=> discard IdInfo on IfaceId bindings
423 tc_iface_decl _ ignore_prags (IfaceId {ifName = occ_name, ifType = iface_type,
424 ifIdDetails = details, ifIdInfo = info})
425 = do { name <- lookupIfaceTop occ_name
426 ; ty <- tcIfaceType iface_type
427 ; details <- tcIdDetails ty details
428 ; info <- tcIdInfo ignore_prags name ty info
429 ; return (AnId (mkGlobalId details name ty info)) }
431 tc_iface_decl parent _ (IfaceData {ifName = occ_name,
433 ifCtxt = ctxt, ifGadtSyntax = gadt_syn,
436 ifGeneric = want_generic,
437 ifFamInst = mb_family })
438 = bindIfaceTyVars_AT tv_bndrs $ \ tyvars -> do
439 { tc_name <- lookupIfaceTop occ_name
440 ; tycon <- fixM ( \ tycon -> do
441 { stupid_theta <- tcIfaceCtxt ctxt
442 ; cons <- tcIfaceDataCons tc_name tycon tyvars rdr_cons
443 ; mb_fam_inst <- tcFamInst mb_family
444 ; buildAlgTyCon tc_name tyvars stupid_theta cons is_rec
445 want_generic gadt_syn parent mb_fam_inst
447 ; traceIf (text "tcIfaceDecl4" <+> ppr tycon)
448 ; return (ATyCon tycon) }
450 tc_iface_decl parent _ (IfaceSyn {ifName = occ_name, ifTyVars = tv_bndrs,
451 ifSynRhs = mb_rhs_ty,
452 ifSynKind = kind, ifFamInst = mb_family})
453 = bindIfaceTyVars_AT tv_bndrs $ \ tyvars -> do
454 { tc_name <- lookupIfaceTop occ_name
455 ; rhs_kind <- tcIfaceType kind -- Note [Synonym kind loop]
456 ; rhs <- forkM (mk_doc tc_name) $
458 ; fam_info <- tcFamInst mb_family
459 ; tycon <- buildSynTyCon tc_name tyvars rhs rhs_kind parent fam_info
460 ; return (ATyCon tycon)
463 mk_doc n = ptext (sLit "Type syonym") <+> ppr n
464 tc_syn_rhs Nothing = return SynFamilyTyCon
465 tc_syn_rhs (Just ty) = do { rhs_ty <- tcIfaceType ty
466 ; return (SynonymTyCon rhs_ty) }
468 tc_iface_decl _parent ignore_prags
469 (IfaceClass {ifCtxt = rdr_ctxt, ifName = occ_name,
470 ifTyVars = tv_bndrs, ifFDs = rdr_fds,
471 ifATs = rdr_ats, ifSigs = rdr_sigs,
473 -- ToDo: in hs-boot files we should really treat abstract classes specially,
474 -- as we do abstract tycons
475 = bindIfaceTyVars tv_bndrs $ \ tyvars -> do
476 { cls_name <- lookupIfaceTop occ_name
477 ; ctxt <- tcIfaceCtxt rdr_ctxt
478 ; sigs <- mapM tc_sig rdr_sigs
479 ; fds <- mapM tc_fd rdr_fds
480 ; cls <- fixM $ \ cls -> do
481 { ats <- mapM (tc_iface_decl (AssocFamilyTyCon cls) ignore_prags) rdr_ats
482 ; buildClass ignore_prags cls_name tyvars ctxt fds ats sigs tc_isrec }
483 ; return (AClass cls) }
485 tc_sig (IfaceClassOp occ dm rdr_ty)
486 = do { op_name <- lookupIfaceTop occ
487 ; op_ty <- forkM (mk_doc op_name rdr_ty) (tcIfaceType rdr_ty)
488 -- Must be done lazily for just the same reason as the
489 -- type of a data con; to avoid sucking in types that
490 -- it mentions unless it's necessray to do so
491 ; return (op_name, dm, op_ty) }
493 mk_doc op_name op_ty = ptext (sLit "Class op") <+> sep [ppr op_name, ppr op_ty]
495 tc_fd (tvs1, tvs2) = do { tvs1' <- mapM tcIfaceTyVar tvs1
496 ; tvs2' <- mapM tcIfaceTyVar tvs2
497 ; return (tvs1', tvs2') }
499 tc_iface_decl _ _ (IfaceForeign {ifName = rdr_name, ifExtName = ext_name})
500 = do { name <- lookupIfaceTop rdr_name
501 ; return (ATyCon (mkForeignTyCon name ext_name
504 tcFamInst :: Maybe (IfaceTyCon, [IfaceType]) -> IfL (Maybe (TyCon, [Type]))
505 tcFamInst Nothing = return Nothing
506 tcFamInst (Just (fam, tys)) = do { famTyCon <- tcIfaceTyCon fam
507 ; insttys <- mapM tcIfaceType tys
508 ; return $ Just (famTyCon, insttys) }
510 tcIfaceDataCons :: Name -> TyCon -> [TyVar] -> IfaceConDecls -> IfL AlgTyConRhs
511 tcIfaceDataCons tycon_name tycon _ if_cons
513 IfAbstractTyCon -> return mkAbstractTyConRhs
514 IfOpenDataTyCon -> return DataFamilyTyCon
515 IfDataTyCon cons -> do { data_cons <- mapM tc_con_decl cons
516 ; return (mkDataTyConRhs data_cons) }
517 IfNewTyCon con -> do { data_con <- tc_con_decl con
518 ; mkNewTyConRhs tycon_name tycon data_con }
520 tc_con_decl (IfCon { ifConInfix = is_infix,
521 ifConUnivTvs = univ_tvs, ifConExTvs = ex_tvs,
522 ifConOcc = occ, ifConCtxt = ctxt, ifConEqSpec = spec,
523 ifConArgTys = args, ifConFields = field_lbls,
524 ifConStricts = stricts})
525 = bindIfaceTyVars univ_tvs $ \ univ_tyvars -> do
526 bindIfaceTyVars ex_tvs $ \ ex_tyvars -> do
527 { name <- lookupIfaceTop occ
528 ; eq_spec <- tcIfaceEqSpec spec
529 ; theta <- tcIfaceCtxt ctxt -- Laziness seems not worth the bother here
530 -- At one stage I thought that this context checking *had*
531 -- to be lazy, because of possible mutual recursion between the
532 -- type and the classe:
534 -- class Real a where { toRat :: a -> Ratio Integer }
535 -- data (Real a) => Ratio a = ...
536 -- But now I think that the laziness in checking class ops breaks
537 -- the loop, so no laziness needed
539 -- Read the argument types, but lazily to avoid faulting in
540 -- the component types unless they are really needed
541 ; arg_tys <- forkM (mk_doc name) (mapM tcIfaceType args)
542 ; lbl_names <- mapM lookupIfaceTop field_lbls
544 -- Remember, tycon is the representation tycon
545 ; let orig_res_ty = mkFamilyTyConApp tycon
546 (substTyVars (mkTopTvSubst eq_spec) univ_tyvars)
548 ; buildDataCon name is_infix {- Not infix -}
550 univ_tyvars ex_tyvars
552 arg_tys orig_res_ty tycon
554 mk_doc con_name = ptext (sLit "Constructor") <+> ppr con_name
556 tcIfaceEqSpec :: [(OccName, IfaceType)] -> IfL [(TyVar, Type)]
560 do_item (occ, if_ty) = do { tv <- tcIfaceTyVar (occNameFS occ)
561 ; ty <- tcIfaceType if_ty
565 Note [Synonym kind loop]
566 ~~~~~~~~~~~~~~~~~~~~~~~~
567 Notice that we eagerly grab the *kind* from the interface file, but
568 build a forkM thunk for the *rhs* (and family stuff). To see why,
569 consider this (Trac #2412)
571 M.hs: module M where { import X; data T = MkT S }
572 X.hs: module X where { import {-# SOURCE #-} M; type S = T }
573 M.hs-boot: module M where { data T }
575 When kind-checking M.hs we need S's kind. But we do not want to
576 find S's kind from (typeKind S-rhs), because we don't want to look at
577 S-rhs yet! Since S is imported from X.hi, S gets just one chance to
578 be defined, and we must not do that until we've finished with M.T.
580 Solution: record S's kind in the interface file; now we can safely
583 %************************************************************************
587 %************************************************************************
590 tcIfaceInst :: IfaceInst -> IfL Instance
591 tcIfaceInst (IfaceInst { ifDFun = dfun_occ, ifOFlag = oflag,
592 ifInstCls = cls, ifInstTys = mb_tcs })
593 = do { dfun <- forkM (ptext (sLit "Dict fun") <+> ppr dfun_occ) $
594 tcIfaceExtId dfun_occ
595 ; let mb_tcs' = map (fmap ifaceTyConName) mb_tcs
596 ; return (mkImportedInstance cls mb_tcs' dfun oflag) }
598 tcIfaceFamInst :: IfaceFamInst -> IfL FamInst
599 tcIfaceFamInst (IfaceFamInst { ifFamInstTyCon = tycon,
600 ifFamInstFam = fam, ifFamInstTys = mb_tcs })
601 -- { tycon' <- forkM (ptext (sLit "Inst tycon") <+> ppr tycon) $
602 -- the above line doesn't work, but this below does => CPP in Haskell = evil!
603 = do tycon' <- forkM (text ("Inst tycon") <+> ppr tycon) $
605 let mb_tcs' = map (fmap ifaceTyConName) mb_tcs
606 return (mkImportedFamInst fam mb_tcs' tycon')
610 %************************************************************************
614 %************************************************************************
616 We move a IfaceRule from eps_rules to eps_rule_base when all its LHS free vars
617 are in the type environment. However, remember that typechecking a Rule may
618 (as a side effect) augment the type envt, and so we may need to iterate the process.
621 tcIfaceRules :: Bool -- True <=> ignore rules
624 tcIfaceRules ignore_prags if_rules
625 | ignore_prags = return []
626 | otherwise = mapM tcIfaceRule if_rules
628 tcIfaceRule :: IfaceRule -> IfL CoreRule
629 tcIfaceRule (IfaceRule {ifRuleName = name, ifActivation = act, ifRuleBndrs = bndrs,
630 ifRuleHead = fn, ifRuleArgs = args, ifRuleRhs = rhs,
632 = do { ~(bndrs', args', rhs') <-
633 -- Typecheck the payload lazily, in the hope it'll never be looked at
634 forkM (ptext (sLit "Rule") <+> ftext name) $
635 bindIfaceBndrs bndrs $ \ bndrs' ->
636 do { args' <- mapM tcIfaceExpr args
637 ; rhs' <- tcIfaceExpr rhs
638 ; return (bndrs', args', rhs') }
639 ; let mb_tcs = map ifTopFreeName args
640 ; return (Rule { ru_name = name, ru_fn = fn, ru_act = act,
641 ru_bndrs = bndrs', ru_args = args',
642 ru_rhs = occurAnalyseExpr rhs',
645 ru_local = False }) } -- An imported RULE is never for a local Id
646 -- or, even if it is (module loop, perhaps)
647 -- we'll just leave it in the non-local set
649 -- This function *must* mirror exactly what Rules.topFreeName does
650 -- We could have stored the ru_rough field in the iface file
651 -- but that would be redundant, I think.
652 -- The only wrinkle is that we must not be deceived by
653 -- type syononyms at the top of a type arg. Since
654 -- we can't tell at this point, we are careful not
655 -- to write them out in coreRuleToIfaceRule
656 ifTopFreeName :: IfaceExpr -> Maybe Name
657 ifTopFreeName (IfaceType (IfaceTyConApp tc _ )) = Just (ifaceTyConName tc)
658 ifTopFreeName (IfaceApp f _) = ifTopFreeName f
659 ifTopFreeName (IfaceExt n) = Just n
660 ifTopFreeName _ = Nothing
664 %************************************************************************
668 %************************************************************************
671 tcIfaceAnnotations :: [IfaceAnnotation] -> IfL [Annotation]
672 tcIfaceAnnotations = mapM tcIfaceAnnotation
674 tcIfaceAnnotation :: IfaceAnnotation -> IfL Annotation
675 tcIfaceAnnotation (IfaceAnnotation target serialized) = do
676 target' <- tcIfaceAnnTarget target
677 return $ Annotation {
678 ann_target = target',
679 ann_value = serialized
682 tcIfaceAnnTarget :: IfaceAnnTarget -> IfL (AnnTarget Name)
683 tcIfaceAnnTarget (NamedTarget occ) = do
684 name <- lookupIfaceTop occ
685 return $ NamedTarget name
686 tcIfaceAnnTarget (ModuleTarget mod) = do
687 return $ ModuleTarget mod
692 %************************************************************************
694 Vectorisation information
696 %************************************************************************
699 tcIfaceVectInfo :: Module -> TypeEnv -> IfaceVectInfo -> IfL VectInfo
700 tcIfaceVectInfo mod typeEnv (IfaceVectInfo
701 { ifaceVectInfoVar = vars
702 , ifaceVectInfoTyCon = tycons
703 , ifaceVectInfoTyConReuse = tyconsReuse
705 = do { vVars <- mapM vectVarMapping vars
706 ; tyConRes1 <- mapM vectTyConMapping tycons
707 ; tyConRes2 <- mapM vectTyConReuseMapping tyconsReuse
708 ; let (vTyCons, vDataCons, vPAs, vIsos) = unzip4 (tyConRes1 ++ tyConRes2)
710 { vectInfoVar = mkVarEnv vVars
711 , vectInfoTyCon = mkNameEnv vTyCons
712 , vectInfoDataCon = mkNameEnv (concat vDataCons)
713 , vectInfoPADFun = mkNameEnv vPAs
714 , vectInfoIso = mkNameEnv vIsos
719 = do { vName <- lookupOrig mod (mkVectOcc (nameOccName name))
720 ; let { var = lookupVar name
721 ; vVar = lookupVar vName
723 ; return (var, (var, vVar))
725 vectTyConMapping name
726 = do { vName <- lookupOrig mod (mkVectTyConOcc (nameOccName name))
727 ; paName <- lookupOrig mod (mkPADFunOcc (nameOccName name))
728 ; isoName <- lookupOrig mod (mkVectIsoOcc (nameOccName name))
729 ; let { tycon = lookupTyCon name
730 ; vTycon = lookupTyCon vName
731 ; paTycon = lookupVar paName
732 ; isoTycon = lookupVar isoName
734 ; vDataCons <- mapM vectDataConMapping (tyConDataCons tycon)
735 ; return ((name, (tycon, vTycon)), -- (T, T_v)
736 vDataCons, -- list of (Ci, Ci_v)
737 (vName, (vTycon, paTycon)), -- (T_v, paT)
738 (name, (tycon, isoTycon))) -- (T, isoT)
740 vectTyConReuseMapping name
741 = do { paName <- lookupOrig mod (mkPADFunOcc (nameOccName name))
742 ; isoName <- lookupOrig mod (mkVectIsoOcc (nameOccName name))
743 ; let { tycon = lookupTyCon name
744 ; paTycon = lookupVar paName
745 ; isoTycon = lookupVar isoName
746 ; vDataCons = [ (dataConName dc, (dc, dc))
747 | dc <- tyConDataCons tycon]
749 ; return ((name, (tycon, tycon)), -- (T, T)
750 vDataCons, -- list of (Ci, Ci)
751 (name, (tycon, paTycon)), -- (T, paT)
752 (name, (tycon, isoTycon))) -- (T, isoT)
754 vectDataConMapping datacon
755 = do { let name = dataConName datacon
756 ; vName <- lookupOrig mod (mkVectDataConOcc (nameOccName name))
757 ; let vDataCon = lookupDataCon vName
758 ; return (name, (datacon, vDataCon))
761 lookupVar name = case lookupTypeEnv typeEnv name of
762 Just (AnId var) -> var
764 panic "TcIface.tcIfaceVectInfo: not an id"
766 panic "TcIface.tcIfaceVectInfo: unknown name"
767 lookupTyCon name = case lookupTypeEnv typeEnv name of
768 Just (ATyCon tc) -> tc
770 panic "TcIface.tcIfaceVectInfo: not a tycon"
772 panic "TcIface.tcIfaceVectInfo: unknown name"
773 lookupDataCon name = case lookupTypeEnv typeEnv name of
774 Just (ADataCon dc) -> dc
776 panic "TcIface.tcIfaceVectInfo: not a datacon"
778 panic "TcIface.tcIfaceVectInfo: unknown name"
781 %************************************************************************
785 %************************************************************************
788 tcIfaceType :: IfaceType -> IfL Type
789 tcIfaceType (IfaceTyVar n) = do { tv <- tcIfaceTyVar n; return (TyVarTy tv) }
790 tcIfaceType (IfaceAppTy t1 t2) = do { t1' <- tcIfaceType t1; t2' <- tcIfaceType t2; return (AppTy t1' t2') }
791 tcIfaceType (IfaceFunTy t1 t2) = do { t1' <- tcIfaceType t1; t2' <- tcIfaceType t2; return (FunTy t1' t2') }
792 tcIfaceType (IfaceTyConApp tc ts) = do { tc' <- tcIfaceTyCon tc; ts' <- tcIfaceTypes ts; return (mkTyConApp tc' ts') }
793 tcIfaceType (IfaceForAllTy tv t) = bindIfaceTyVar tv $ \ tv' -> do { t' <- tcIfaceType t; return (ForAllTy tv' t') }
794 tcIfaceType (IfacePredTy st) = do { st' <- tcIfacePredType st; return (PredTy st') }
796 tcIfaceTypes :: [IfaceType] -> IfL [Type]
797 tcIfaceTypes tys = mapM tcIfaceType tys
799 -----------------------------------------
800 tcIfacePredType :: IfacePredType -> IfL PredType
801 tcIfacePredType (IfaceClassP cls ts) = do { cls' <- tcIfaceClass cls; ts' <- tcIfaceTypes ts; return (ClassP cls' ts') }
802 tcIfacePredType (IfaceIParam ip t) = do { ip' <- newIPName ip; t' <- tcIfaceType t; return (IParam ip' t') }
803 tcIfacePredType (IfaceEqPred t1 t2) = do { t1' <- tcIfaceType t1; t2' <- tcIfaceType t2; return (EqPred t1' t2') }
805 -----------------------------------------
806 tcIfaceCtxt :: IfaceContext -> IfL ThetaType
807 tcIfaceCtxt sts = mapM tcIfacePredType sts
811 %************************************************************************
815 %************************************************************************
818 tcIfaceExpr :: IfaceExpr -> IfL CoreExpr
819 tcIfaceExpr (IfaceType ty)
820 = Type <$> tcIfaceType ty
822 tcIfaceExpr (IfaceLcl name)
823 = Var <$> tcIfaceLclId name
825 tcIfaceExpr (IfaceTick modName tickNo)
826 = Var <$> tcIfaceTick modName tickNo
828 tcIfaceExpr (IfaceExt gbl)
829 = Var <$> tcIfaceExtId gbl
831 tcIfaceExpr (IfaceLit lit)
834 tcIfaceExpr (IfaceFCall cc ty) = do
835 ty' <- tcIfaceType ty
837 return (Var (mkFCallId u cc ty'))
839 tcIfaceExpr (IfaceTuple boxity args) = do
840 args' <- mapM tcIfaceExpr args
841 -- Put the missing type arguments back in
842 let con_args = map (Type . exprType) args' ++ args'
843 return (mkApps (Var con_id) con_args)
846 con_id = dataConWorkId (tupleCon boxity arity)
849 tcIfaceExpr (IfaceLam bndr body)
850 = bindIfaceBndr bndr $ \bndr' ->
851 Lam bndr' <$> tcIfaceExpr body
853 tcIfaceExpr (IfaceApp fun arg)
854 = App <$> tcIfaceExpr fun <*> tcIfaceExpr arg
856 tcIfaceExpr (IfaceCase scrut case_bndr ty alts) = do
857 scrut' <- tcIfaceExpr scrut
858 case_bndr_name <- newIfaceName (mkVarOccFS case_bndr)
860 scrut_ty = exprType scrut'
861 case_bndr' = mkLocalId case_bndr_name scrut_ty
862 tc_app = splitTyConApp scrut_ty
863 -- NB: Won't always succeed (polymoprhic case)
864 -- but won't be demanded in those cases
865 -- NB: not tcSplitTyConApp; we are looking at Core here
866 -- look through non-rec newtypes to find the tycon that
867 -- corresponds to the datacon in this case alternative
869 extendIfaceIdEnv [case_bndr'] $ do
870 alts' <- mapM (tcIfaceAlt scrut' tc_app) alts
871 ty' <- tcIfaceType ty
872 return (Case scrut' case_bndr' ty' alts')
874 tcIfaceExpr (IfaceLet (IfaceNonRec bndr rhs) body) = do
875 rhs' <- tcIfaceExpr rhs
876 id <- tcIfaceLetBndr bndr
877 body' <- extendIfaceIdEnv [id] (tcIfaceExpr body)
878 return (Let (NonRec id rhs') body')
880 tcIfaceExpr (IfaceLet (IfaceRec pairs) body) = do
881 ids <- mapM tcIfaceLetBndr bndrs
882 extendIfaceIdEnv ids $ do
883 rhss' <- mapM tcIfaceExpr rhss
884 body' <- tcIfaceExpr body
885 return (Let (Rec (ids `zip` rhss')) body')
887 (bndrs, rhss) = unzip pairs
889 tcIfaceExpr (IfaceCast expr co) = do
890 expr' <- tcIfaceExpr expr
891 co' <- tcIfaceType co
892 return (Cast expr' co')
894 tcIfaceExpr (IfaceNote note expr) = do
895 expr' <- tcIfaceExpr expr
897 IfaceSCC cc -> return (Note (SCC cc) expr')
898 IfaceCoreNote n -> return (Note (CoreNote n) expr')
900 -------------------------
901 tcIfaceAlt :: CoreExpr -> (TyCon, [Type])
902 -> (IfaceConAlt, [FastString], IfaceExpr)
903 -> IfL (AltCon, [TyVar], CoreExpr)
904 tcIfaceAlt _ _ (IfaceDefault, names, rhs)
905 = ASSERT( null names ) do
906 rhs' <- tcIfaceExpr rhs
907 return (DEFAULT, [], rhs')
909 tcIfaceAlt _ _ (IfaceLitAlt lit, names, rhs)
910 = ASSERT( null names ) do
911 rhs' <- tcIfaceExpr rhs
912 return (LitAlt lit, [], rhs')
914 -- A case alternative is made quite a bit more complicated
915 -- by the fact that we omit type annotations because we can
916 -- work them out. True enough, but its not that easy!
917 tcIfaceAlt scrut (tycon, inst_tys) (IfaceDataAlt data_occ, arg_strs, rhs)
918 = do { con <- tcIfaceDataCon data_occ
919 ; when (debugIsOn && not (con `elem` tyConDataCons tycon))
920 (failIfM (ppr scrut $$ ppr con $$ ppr tycon $$ ppr (tyConDataCons tycon)))
921 ; tcIfaceDataAlt con inst_tys arg_strs rhs }
923 tcIfaceAlt _ (tycon, inst_tys) (IfaceTupleAlt _boxity, arg_occs, rhs)
924 = ASSERT2( isTupleTyCon tycon, ppr tycon )
925 do { let [data_con] = tyConDataCons tycon
926 ; tcIfaceDataAlt data_con inst_tys arg_occs rhs }
928 tcIfaceDataAlt :: DataCon -> [Type] -> [FastString] -> IfaceExpr
929 -> IfL (AltCon, [TyVar], CoreExpr)
930 tcIfaceDataAlt con inst_tys arg_strs rhs
931 = do { us <- newUniqueSupply
932 ; let uniqs = uniqsFromSupply us
933 ; let (ex_tvs, co_tvs, arg_ids)
934 = dataConRepFSInstPat arg_strs uniqs con inst_tys
935 all_tvs = ex_tvs ++ co_tvs
937 ; rhs' <- extendIfaceTyVarEnv all_tvs $
938 extendIfaceIdEnv arg_ids $
940 ; return (DataAlt con, all_tvs ++ arg_ids, rhs') }
945 tcExtCoreBindings :: [IfaceBinding] -> IfL [CoreBind] -- Used for external core
946 tcExtCoreBindings [] = return []
947 tcExtCoreBindings (b:bs) = do_one b (tcExtCoreBindings bs)
949 do_one :: IfaceBinding -> IfL [CoreBind] -> IfL [CoreBind]
950 do_one (IfaceNonRec bndr rhs) thing_inside
951 = do { rhs' <- tcIfaceExpr rhs
952 ; bndr' <- newExtCoreBndr bndr
953 ; extendIfaceIdEnv [bndr'] $ do
954 { core_binds <- thing_inside
955 ; return (NonRec bndr' rhs' : core_binds) }}
957 do_one (IfaceRec pairs) thing_inside
958 = do { bndrs' <- mapM newExtCoreBndr bndrs
959 ; extendIfaceIdEnv bndrs' $ do
960 { rhss' <- mapM tcIfaceExpr rhss
961 ; core_binds <- thing_inside
962 ; return (Rec (bndrs' `zip` rhss') : core_binds) }}
964 (bndrs,rhss) = unzip pairs
968 %************************************************************************
972 %************************************************************************
975 tcIdDetails :: Type -> IfaceIdDetails -> IfL IdDetails
976 tcIdDetails _ IfVanillaId = return VanillaId
977 tcIdDetails ty IfDFunId
978 = return (DFunId (isNewTyCon (classTyCon cls)))
980 (_, cls, _) = tcSplitDFunTy ty
982 tcIdDetails _ (IfRecSelId tc naughty)
983 = do { tc' <- tcIfaceTyCon tc
984 ; return (RecSelId { sel_tycon = tc', sel_naughty = naughty }) }
986 tcIdInfo :: Bool -> Name -> Type -> IfaceIdInfo -> IfL IdInfo
987 tcIdInfo ignore_prags name ty info
988 | ignore_prags = return vanillaIdInfo
989 | otherwise = case info of
990 NoInfo -> return vanillaIdInfo
991 HasInfo info -> foldlM tcPrag init_info info
993 -- Set the CgInfo to something sensible but uninformative before
994 -- we start; default assumption is that it has CAFs
995 init_info = vanillaIdInfo
997 tcPrag :: IdInfo -> IfaceInfoItem -> IfL IdInfo
998 tcPrag info HsNoCafRefs = return (info `setCafInfo` NoCafRefs)
999 tcPrag info (HsArity arity) = return (info `setArityInfo` arity)
1000 tcPrag info (HsStrictness str) = return (info `setStrictnessInfo` Just str)
1001 tcPrag info (HsInline prag) = return (info `setInlinePragInfo` prag)
1003 -- The next two are lazy, so they don't transitively suck stuff in
1004 tcPrag info (HsUnfold lb if_unf)
1005 = do { unf <- tcUnfolding name ty info if_unf
1006 ; let info1 | lb = info `setOccInfo` nonRuleLoopBreaker
1008 ; return (info1 `setUnfoldingInfoLazily` unf) }
1012 tcUnfolding :: Name -> Type -> IdInfo -> IfaceUnfolding -> IfL Unfolding
1013 tcUnfolding name _ info (IfCoreUnfold stable if_expr)
1014 = do { mb_expr <- tcPragExpr name if_expr
1015 ; let unf_src = if stable then InlineStable else InlineRhs
1016 ; return (case mb_expr of
1017 Nothing -> NoUnfolding
1018 Just expr -> mkUnfolding unf_src
1019 True {- Top level -}
1020 is_bottoming expr) }
1022 -- Strictness should occur before unfolding!
1023 is_bottoming = case strictnessInfo info of
1024 Just sig -> isBottomingSig sig
1027 tcUnfolding name _ _ (IfCompulsory if_expr)
1028 = do { mb_expr <- tcPragExpr name if_expr
1029 ; return (case mb_expr of
1030 Nothing -> NoUnfolding
1031 Just expr -> mkCompulsoryUnfolding expr) }
1033 tcUnfolding name _ _ (IfInlineRule arity unsat_ok boring_ok if_expr)
1034 = do { mb_expr <- tcPragExpr name if_expr
1035 ; return (case mb_expr of
1036 Nothing -> NoUnfolding
1037 Just expr -> mkCoreUnfolding InlineStable True expr arity
1038 (UnfWhen unsat_ok boring_ok))
1041 tcUnfolding name ty info (IfWrapper arity wkr)
1042 = do { mb_wkr_id <- forkM_maybe doc (tcIfaceExtId wkr)
1043 ; us <- newUniqueSupply
1044 ; return (case mb_wkr_id of
1045 Nothing -> noUnfolding
1046 Just wkr_id -> make_inline_rule wkr_id us) }
1048 doc = text "Worker for" <+> ppr name
1050 make_inline_rule wkr_id us
1051 = mkWwInlineRule wkr_id
1052 (initUs_ us (mkWrapper ty strict_sig) wkr_id)
1055 -- Again we rely here on strictness info always appearing
1057 strict_sig = case strictnessInfo info of
1059 Nothing -> pprPanic "Worker info but no strictness for" (ppr wkr)
1061 tcUnfolding name dfun_ty _ (IfDFunUnfold ops)
1062 = do { mb_ops1 <- forkM_maybe doc $ mapM tcIfaceExpr ops
1063 ; return (case mb_ops1 of
1064 Nothing -> noUnfolding
1065 Just ops1 -> mkDFunUnfolding dfun_ty ops1) }
1067 doc = text "Class ops for dfun" <+> ppr name
1070 For unfoldings we try to do the job lazily, so that we never type check
1071 an unfolding that isn't going to be looked at.
1074 tcPragExpr :: Name -> IfaceExpr -> IfL (Maybe CoreExpr)
1075 tcPragExpr name expr
1076 = forkM_maybe doc $ do
1077 core_expr' <- tcIfaceExpr expr
1079 -- Check for type consistency in the unfolding
1080 ifDOptM Opt_DoCoreLinting $ do
1081 in_scope <- get_in_scope_ids
1082 case lintUnfolding noSrcLoc in_scope core_expr' of
1083 Nothing -> return ()
1084 Just fail_msg -> pprPanic "Iface Lint failure" (hang doc 2 fail_msg)
1088 doc = text "Unfolding of" <+> ppr name
1089 get_in_scope_ids -- Urgh; but just for linting
1091 do { env <- getGblEnv
1092 ; case if_rec_types env of {
1093 Nothing -> return [] ;
1094 Just (_, get_env) -> do
1095 { type_env <- get_env
1096 ; return (typeEnvIds type_env) }}}
1101 %************************************************************************
1103 Getting from Names to TyThings
1105 %************************************************************************
1108 tcIfaceGlobal :: Name -> IfL TyThing
1110 | Just thing <- wiredInNameTyThing_maybe name
1111 -- Wired-in things include TyCons, DataCons, and Ids
1112 = do { ifCheckWiredInThing thing; return thing }
1114 = do { env <- getGblEnv
1115 ; case if_rec_types env of { -- Note [Tying the knot]
1116 Just (mod, get_type_env)
1117 | nameIsLocalOrFrom mod name
1118 -> do -- It's defined in the module being compiled
1119 { type_env <- setLclEnv () get_type_env -- yuk
1120 ; case lookupNameEnv type_env name of
1121 Just thing -> return thing
1122 Nothing -> pprPanic "tcIfaceGlobal (local): not found:"
1123 (ppr name $$ ppr type_env) }
1127 { hsc_env <- getTopEnv
1128 ; mb_thing <- liftIO (lookupTypeHscEnv hsc_env name)
1129 ; case mb_thing of {
1130 Just thing -> return thing ;
1133 { mb_thing <- importDecl name -- It's imported; go get it
1135 Failed err -> failIfM err
1136 Succeeded thing -> return thing
1139 -- Note [Tying the knot]
1140 -- ~~~~~~~~~~~~~~~~~~~~~
1141 -- The if_rec_types field is used in two situations:
1143 -- a) Compiling M.hs, which indiretly imports Foo.hi, which mentions M.T
1144 -- Then we look up M.T in M's type environment, which is splatted into if_rec_types
1145 -- after we've built M's type envt.
1147 -- b) In ghc --make, during the upsweep, we encounter M.hs, whose interface M.hi
1148 -- is up to date. So we call typecheckIface on M.hi. This splats M.T into
1149 -- if_rec_types so that the (lazily typechecked) decls see all the other decls
1151 -- In case (b) it's important to do the if_rec_types check *before* looking in the HPT
1152 -- Because if M.hs also has M.hs-boot, M.T will *already be* in the HPT, but in its
1153 -- emasculated form (e.g. lacking data constructors).
1155 tcIfaceTyCon :: IfaceTyCon -> IfL TyCon
1156 tcIfaceTyCon IfaceIntTc = tcWiredInTyCon intTyCon
1157 tcIfaceTyCon IfaceBoolTc = tcWiredInTyCon boolTyCon
1158 tcIfaceTyCon IfaceCharTc = tcWiredInTyCon charTyCon
1159 tcIfaceTyCon IfaceListTc = tcWiredInTyCon listTyCon
1160 tcIfaceTyCon IfacePArrTc = tcWiredInTyCon parrTyCon
1161 tcIfaceTyCon (IfaceTupTc bx ar) = tcWiredInTyCon (tupleTyCon bx ar)
1162 tcIfaceTyCon (IfaceAnyTc kind) = do { tc_kind <- tcIfaceType kind
1163 ; tcWiredInTyCon (anyTyConOfKind tc_kind) }
1164 tcIfaceTyCon (IfaceTc name) = do { thing <- tcIfaceGlobal name
1165 ; return (check_tc (tyThingTyCon thing)) }
1168 | debugIsOn = case toIfaceTyCon tc of
1170 _ -> pprTrace "check_tc" (ppr tc) tc
1172 -- we should be okay just returning Kind constructors without extra loading
1173 tcIfaceTyCon IfaceLiftedTypeKindTc = return liftedTypeKindTyCon
1174 tcIfaceTyCon IfaceOpenTypeKindTc = return openTypeKindTyCon
1175 tcIfaceTyCon IfaceUnliftedTypeKindTc = return unliftedTypeKindTyCon
1176 tcIfaceTyCon IfaceArgTypeKindTc = return argTypeKindTyCon
1177 tcIfaceTyCon IfaceUbxTupleKindTc = return ubxTupleKindTyCon
1179 -- Even though we are in an interface file, we want to make
1180 -- sure the instances and RULES of this tycon are loaded
1181 -- Imagine: f :: Double -> Double
1182 tcWiredInTyCon :: TyCon -> IfL TyCon
1183 tcWiredInTyCon tc = do { ifCheckWiredInThing (ATyCon tc)
1186 tcIfaceClass :: Name -> IfL Class
1187 tcIfaceClass name = do { thing <- tcIfaceGlobal name
1188 ; return (tyThingClass thing) }
1190 tcIfaceDataCon :: Name -> IfL DataCon
1191 tcIfaceDataCon name = do { thing <- tcIfaceGlobal name
1193 ADataCon dc -> return dc
1194 _ -> pprPanic "tcIfaceExtDC" (ppr name$$ ppr thing) }
1196 tcIfaceExtId :: Name -> IfL Id
1197 tcIfaceExtId name = do { thing <- tcIfaceGlobal name
1199 AnId id -> return id
1200 _ -> pprPanic "tcIfaceExtId" (ppr name$$ ppr thing) }
1203 %************************************************************************
1207 %************************************************************************
1210 bindIfaceBndr :: IfaceBndr -> (CoreBndr -> IfL a) -> IfL a
1211 bindIfaceBndr (IfaceIdBndr (fs, ty)) thing_inside
1212 = do { name <- newIfaceName (mkVarOccFS fs)
1213 ; ty' <- tcIfaceType ty
1214 ; let id = mkLocalId name ty'
1215 ; extendIfaceIdEnv [id] (thing_inside id) }
1216 bindIfaceBndr (IfaceTvBndr bndr) thing_inside
1217 = bindIfaceTyVar bndr thing_inside
1219 bindIfaceBndrs :: [IfaceBndr] -> ([CoreBndr] -> IfL a) -> IfL a
1220 bindIfaceBndrs [] thing_inside = thing_inside []
1221 bindIfaceBndrs (b:bs) thing_inside
1222 = bindIfaceBndr b $ \ b' ->
1223 bindIfaceBndrs bs $ \ bs' ->
1224 thing_inside (b':bs')
1227 -----------------------
1228 tcIfaceLetBndr :: IfaceLetBndr -> IfL Id
1229 tcIfaceLetBndr (IfLetBndr fs ty info)
1230 = do { name <- newIfaceName (mkVarOccFS fs)
1231 ; ty' <- tcIfaceType ty
1233 NoInfo -> return (mkLocalId name ty')
1234 HasInfo i -> return (mkLocalIdWithInfo name ty' (tc_info i)) }
1236 -- Similar to tcIdInfo, but much simpler
1237 tc_info [] = vanillaIdInfo
1238 tc_info (HsInline p : i) = tc_info i `setInlinePragInfo` p
1239 tc_info (HsArity a : i) = tc_info i `setArityInfo` a
1240 tc_info (HsStrictness s : i) = tc_info i `setStrictnessInfo` Just s
1241 tc_info (other : i) = pprTrace "tcIfaceLetBndr: discarding unexpected IdInfo"
1242 (ppr other) (tc_info i)
1244 -----------------------
1245 newExtCoreBndr :: IfaceLetBndr -> IfL Id
1246 newExtCoreBndr (IfLetBndr var ty _) -- Ignoring IdInfo for now
1247 = do { mod <- getIfModule
1248 ; name <- newGlobalBinder mod (mkVarOccFS var) noSrcSpan
1249 ; ty' <- tcIfaceType ty
1250 ; return (mkLocalId name ty') }
1252 -----------------------
1253 bindIfaceTyVar :: IfaceTvBndr -> (TyVar -> IfL a) -> IfL a
1254 bindIfaceTyVar (occ,kind) thing_inside
1255 = do { name <- newIfaceName (mkTyVarOccFS occ)
1256 ; tyvar <- mk_iface_tyvar name kind
1257 ; extendIfaceTyVarEnv [tyvar] (thing_inside tyvar) }
1259 bindIfaceTyVars :: [IfaceTvBndr] -> ([TyVar] -> IfL a) -> IfL a
1260 bindIfaceTyVars bndrs thing_inside
1261 = do { names <- newIfaceNames (map mkTyVarOccFS occs)
1262 ; tyvars <- zipWithM mk_iface_tyvar names kinds
1263 ; extendIfaceTyVarEnv tyvars (thing_inside tyvars) }
1265 (occs,kinds) = unzip bndrs
1267 mk_iface_tyvar :: Name -> IfaceKind -> IfL TyVar
1268 mk_iface_tyvar name ifKind
1269 = do { kind <- tcIfaceType ifKind
1270 ; if isCoercionKind kind then
1271 return (Var.mkCoVar name kind)
1273 return (Var.mkTyVar name kind) }
1275 bindIfaceTyVars_AT :: [IfaceTvBndr] -> ([TyVar] -> IfL a) -> IfL a
1276 -- Used for type variable in nested associated data/type declarations
1277 -- where some of the type variables are already in scope
1278 -- class C a where { data T a b }
1279 -- Here 'a' is in scope when we look at the 'data T'
1280 bindIfaceTyVars_AT [] thing_inside
1282 bindIfaceTyVars_AT (b@(tv_occ,_) : bs) thing_inside
1283 = bindIfaceTyVars_AT bs $ \ bs' ->
1284 do { mb_tv <- lookupIfaceTyVar tv_occ
1286 Just b' -> thing_inside (b':bs')
1287 Nothing -> bindIfaceTyVar b $ \ b' ->
1288 thing_inside (b':bs') }