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 })
631 = do { ~(bndrs', args', rhs') <-
632 -- Typecheck the payload lazily, in the hope it'll never be looked at
633 forkM (ptext (sLit "Rule") <+> ftext name) $
634 bindIfaceBndrs bndrs $ \ bndrs' ->
635 do { args' <- mapM tcIfaceExpr args
636 ; rhs' <- tcIfaceExpr rhs
637 ; return (bndrs', args', rhs') }
638 ; let mb_tcs = map ifTopFreeName args
639 ; return (Rule { ru_name = name, ru_fn = fn, ru_act = act,
640 ru_bndrs = bndrs', ru_args = args',
641 ru_rhs = occurAnalyseExpr rhs',
643 ru_local = False }) } -- An imported RULE is never for a local Id
644 -- or, even if it is (module loop, perhaps)
645 -- we'll just leave it in the non-local set
647 -- This function *must* mirror exactly what Rules.topFreeName does
648 -- We could have stored the ru_rough field in the iface file
649 -- but that would be redundant, I think.
650 -- The only wrinkle is that we must not be deceived by
651 -- type syononyms at the top of a type arg. Since
652 -- we can't tell at this point, we are careful not
653 -- to write them out in coreRuleToIfaceRule
654 ifTopFreeName :: IfaceExpr -> Maybe Name
655 ifTopFreeName (IfaceType (IfaceTyConApp tc _ )) = Just (ifaceTyConName tc)
656 ifTopFreeName (IfaceApp f _) = ifTopFreeName f
657 ifTopFreeName (IfaceExt n) = Just n
658 ifTopFreeName _ = Nothing
662 %************************************************************************
666 %************************************************************************
669 tcIfaceAnnotations :: [IfaceAnnotation] -> IfL [Annotation]
670 tcIfaceAnnotations = mapM tcIfaceAnnotation
672 tcIfaceAnnotation :: IfaceAnnotation -> IfL Annotation
673 tcIfaceAnnotation (IfaceAnnotation target serialized) = do
674 target' <- tcIfaceAnnTarget target
675 return $ Annotation {
676 ann_target = target',
677 ann_value = serialized
680 tcIfaceAnnTarget :: IfaceAnnTarget -> IfL (AnnTarget Name)
681 tcIfaceAnnTarget (NamedTarget occ) = do
682 name <- lookupIfaceTop occ
683 return $ NamedTarget name
684 tcIfaceAnnTarget (ModuleTarget mod) = do
685 return $ ModuleTarget mod
690 %************************************************************************
692 Vectorisation information
694 %************************************************************************
697 tcIfaceVectInfo :: Module -> TypeEnv -> IfaceVectInfo -> IfL VectInfo
698 tcIfaceVectInfo mod typeEnv (IfaceVectInfo
699 { ifaceVectInfoVar = vars
700 , ifaceVectInfoTyCon = tycons
701 , ifaceVectInfoTyConReuse = tyconsReuse
703 = do { vVars <- mapM vectVarMapping vars
704 ; tyConRes1 <- mapM vectTyConMapping tycons
705 ; tyConRes2 <- mapM vectTyConReuseMapping tyconsReuse
706 ; let (vTyCons, vDataCons, vPAs, vIsos) = unzip4 (tyConRes1 ++ tyConRes2)
708 { vectInfoVar = mkVarEnv vVars
709 , vectInfoTyCon = mkNameEnv vTyCons
710 , vectInfoDataCon = mkNameEnv (concat vDataCons)
711 , vectInfoPADFun = mkNameEnv vPAs
712 , vectInfoIso = mkNameEnv vIsos
717 = do { vName <- lookupOrig mod (mkVectOcc (nameOccName name))
718 ; let { var = lookupVar name
719 ; vVar = lookupVar vName
721 ; return (var, (var, vVar))
723 vectTyConMapping name
724 = do { vName <- lookupOrig mod (mkVectTyConOcc (nameOccName name))
725 ; paName <- lookupOrig mod (mkPADFunOcc (nameOccName name))
726 ; isoName <- lookupOrig mod (mkVectIsoOcc (nameOccName name))
727 ; let { tycon = lookupTyCon name
728 ; vTycon = lookupTyCon vName
729 ; paTycon = lookupVar paName
730 ; isoTycon = lookupVar isoName
732 ; vDataCons <- mapM vectDataConMapping (tyConDataCons tycon)
733 ; return ((name, (tycon, vTycon)), -- (T, T_v)
734 vDataCons, -- list of (Ci, Ci_v)
735 (vName, (vTycon, paTycon)), -- (T_v, paT)
736 (name, (tycon, isoTycon))) -- (T, isoT)
738 vectTyConReuseMapping name
739 = do { paName <- lookupOrig mod (mkPADFunOcc (nameOccName name))
740 ; isoName <- lookupOrig mod (mkVectIsoOcc (nameOccName name))
741 ; let { tycon = lookupTyCon name
742 ; paTycon = lookupVar paName
743 ; isoTycon = lookupVar isoName
744 ; vDataCons = [ (dataConName dc, (dc, dc))
745 | dc <- tyConDataCons tycon]
747 ; return ((name, (tycon, tycon)), -- (T, T)
748 vDataCons, -- list of (Ci, Ci)
749 (name, (tycon, paTycon)), -- (T, paT)
750 (name, (tycon, isoTycon))) -- (T, isoT)
752 vectDataConMapping datacon
753 = do { let name = dataConName datacon
754 ; vName <- lookupOrig mod (mkVectDataConOcc (nameOccName name))
755 ; let vDataCon = lookupDataCon vName
756 ; return (name, (datacon, vDataCon))
759 lookupVar name = case lookupTypeEnv typeEnv name of
760 Just (AnId var) -> var
762 panic "TcIface.tcIfaceVectInfo: not an id"
764 panic "TcIface.tcIfaceVectInfo: unknown name"
765 lookupTyCon name = case lookupTypeEnv typeEnv name of
766 Just (ATyCon tc) -> tc
768 panic "TcIface.tcIfaceVectInfo: not a tycon"
770 panic "TcIface.tcIfaceVectInfo: unknown name"
771 lookupDataCon name = case lookupTypeEnv typeEnv name of
772 Just (ADataCon dc) -> dc
774 panic "TcIface.tcIfaceVectInfo: not a datacon"
776 panic "TcIface.tcIfaceVectInfo: unknown name"
779 %************************************************************************
783 %************************************************************************
786 tcIfaceType :: IfaceType -> IfL Type
787 tcIfaceType (IfaceTyVar n) = do { tv <- tcIfaceTyVar n; return (TyVarTy tv) }
788 tcIfaceType (IfaceAppTy t1 t2) = do { t1' <- tcIfaceType t1; t2' <- tcIfaceType t2; return (AppTy t1' t2') }
789 tcIfaceType (IfaceFunTy t1 t2) = do { t1' <- tcIfaceType t1; t2' <- tcIfaceType t2; return (FunTy t1' t2') }
790 tcIfaceType (IfaceTyConApp tc ts) = do { tc' <- tcIfaceTyCon tc; ts' <- tcIfaceTypes ts; return (mkTyConApp tc' ts') }
791 tcIfaceType (IfaceForAllTy tv t) = bindIfaceTyVar tv $ \ tv' -> do { t' <- tcIfaceType t; return (ForAllTy tv' t') }
792 tcIfaceType (IfacePredTy st) = do { st' <- tcIfacePredType st; return (PredTy st') }
794 tcIfaceTypes :: [IfaceType] -> IfL [Type]
795 tcIfaceTypes tys = mapM tcIfaceType tys
797 -----------------------------------------
798 tcIfacePredType :: IfacePredType -> IfL PredType
799 tcIfacePredType (IfaceClassP cls ts) = do { cls' <- tcIfaceClass cls; ts' <- tcIfaceTypes ts; return (ClassP cls' ts') }
800 tcIfacePredType (IfaceIParam ip t) = do { ip' <- newIPName ip; t' <- tcIfaceType t; return (IParam ip' t') }
801 tcIfacePredType (IfaceEqPred t1 t2) = do { t1' <- tcIfaceType t1; t2' <- tcIfaceType t2; return (EqPred t1' t2') }
803 -----------------------------------------
804 tcIfaceCtxt :: IfaceContext -> IfL ThetaType
805 tcIfaceCtxt sts = mapM tcIfacePredType sts
809 %************************************************************************
813 %************************************************************************
816 tcIfaceExpr :: IfaceExpr -> IfL CoreExpr
817 tcIfaceExpr (IfaceType ty)
818 = Type <$> tcIfaceType ty
820 tcIfaceExpr (IfaceLcl name)
821 = Var <$> tcIfaceLclId name
823 tcIfaceExpr (IfaceTick modName tickNo)
824 = Var <$> tcIfaceTick modName tickNo
826 tcIfaceExpr (IfaceExt gbl)
827 = Var <$> tcIfaceExtId gbl
829 tcIfaceExpr (IfaceLit lit)
832 tcIfaceExpr (IfaceFCall cc ty) = do
833 ty' <- tcIfaceType ty
835 return (Var (mkFCallId u cc ty'))
837 tcIfaceExpr (IfaceTuple boxity args) = do
838 args' <- mapM tcIfaceExpr args
839 -- Put the missing type arguments back in
840 let con_args = map (Type . exprType) args' ++ args'
841 return (mkApps (Var con_id) con_args)
844 con_id = dataConWorkId (tupleCon boxity arity)
847 tcIfaceExpr (IfaceLam bndr body)
848 = bindIfaceBndr bndr $ \bndr' ->
849 Lam bndr' <$> tcIfaceExpr body
851 tcIfaceExpr (IfaceApp fun arg)
852 = App <$> tcIfaceExpr fun <*> tcIfaceExpr arg
854 tcIfaceExpr (IfaceCase scrut case_bndr ty alts) = do
855 scrut' <- tcIfaceExpr scrut
856 case_bndr_name <- newIfaceName (mkVarOccFS case_bndr)
858 scrut_ty = exprType scrut'
859 case_bndr' = mkLocalId case_bndr_name scrut_ty
860 tc_app = splitTyConApp scrut_ty
861 -- NB: Won't always succeed (polymoprhic case)
862 -- but won't be demanded in those cases
863 -- NB: not tcSplitTyConApp; we are looking at Core here
864 -- look through non-rec newtypes to find the tycon that
865 -- corresponds to the datacon in this case alternative
867 extendIfaceIdEnv [case_bndr'] $ do
868 alts' <- mapM (tcIfaceAlt scrut' tc_app) alts
869 ty' <- tcIfaceType ty
870 return (Case scrut' case_bndr' ty' alts')
872 tcIfaceExpr (IfaceLet (IfaceNonRec bndr rhs) body) = do
873 rhs' <- tcIfaceExpr rhs
874 id <- tcIfaceLetBndr bndr
875 body' <- extendIfaceIdEnv [id] (tcIfaceExpr body)
876 return (Let (NonRec id rhs') body')
878 tcIfaceExpr (IfaceLet (IfaceRec pairs) body) = do
879 ids <- mapM tcIfaceLetBndr bndrs
880 extendIfaceIdEnv ids $ do
881 rhss' <- mapM tcIfaceExpr rhss
882 body' <- tcIfaceExpr body
883 return (Let (Rec (ids `zip` rhss')) body')
885 (bndrs, rhss) = unzip pairs
887 tcIfaceExpr (IfaceCast expr co) = do
888 expr' <- tcIfaceExpr expr
889 co' <- tcIfaceType co
890 return (Cast expr' co')
892 tcIfaceExpr (IfaceNote note expr) = do
893 expr' <- tcIfaceExpr expr
895 IfaceSCC cc -> return (Note (SCC cc) expr')
896 IfaceCoreNote n -> return (Note (CoreNote n) expr')
898 -------------------------
899 tcIfaceAlt :: CoreExpr -> (TyCon, [Type])
900 -> (IfaceConAlt, [FastString], IfaceExpr)
901 -> IfL (AltCon, [TyVar], CoreExpr)
902 tcIfaceAlt _ _ (IfaceDefault, names, rhs)
903 = ASSERT( null names ) do
904 rhs' <- tcIfaceExpr rhs
905 return (DEFAULT, [], rhs')
907 tcIfaceAlt _ _ (IfaceLitAlt lit, names, rhs)
908 = ASSERT( null names ) do
909 rhs' <- tcIfaceExpr rhs
910 return (LitAlt lit, [], rhs')
912 -- A case alternative is made quite a bit more complicated
913 -- by the fact that we omit type annotations because we can
914 -- work them out. True enough, but its not that easy!
915 tcIfaceAlt scrut (tycon, inst_tys) (IfaceDataAlt data_occ, arg_strs, rhs)
916 = do { con <- tcIfaceDataCon data_occ
917 ; when (debugIsOn && not (con `elem` tyConDataCons tycon))
918 (failIfM (ppr scrut $$ ppr con $$ ppr tycon $$ ppr (tyConDataCons tycon)))
919 ; tcIfaceDataAlt con inst_tys arg_strs rhs }
921 tcIfaceAlt _ (tycon, inst_tys) (IfaceTupleAlt _boxity, arg_occs, rhs)
922 = ASSERT2( isTupleTyCon tycon, ppr tycon )
923 do { let [data_con] = tyConDataCons tycon
924 ; tcIfaceDataAlt data_con inst_tys arg_occs rhs }
926 tcIfaceDataAlt :: DataCon -> [Type] -> [FastString] -> IfaceExpr
927 -> IfL (AltCon, [TyVar], CoreExpr)
928 tcIfaceDataAlt con inst_tys arg_strs rhs
929 = do { us <- newUniqueSupply
930 ; let uniqs = uniqsFromSupply us
931 ; let (ex_tvs, co_tvs, arg_ids)
932 = dataConRepFSInstPat arg_strs uniqs con inst_tys
933 all_tvs = ex_tvs ++ co_tvs
935 ; rhs' <- extendIfaceTyVarEnv all_tvs $
936 extendIfaceIdEnv arg_ids $
938 ; return (DataAlt con, all_tvs ++ arg_ids, rhs') }
943 tcExtCoreBindings :: [IfaceBinding] -> IfL [CoreBind] -- Used for external core
944 tcExtCoreBindings [] = return []
945 tcExtCoreBindings (b:bs) = do_one b (tcExtCoreBindings bs)
947 do_one :: IfaceBinding -> IfL [CoreBind] -> IfL [CoreBind]
948 do_one (IfaceNonRec bndr rhs) thing_inside
949 = do { rhs' <- tcIfaceExpr rhs
950 ; bndr' <- newExtCoreBndr bndr
951 ; extendIfaceIdEnv [bndr'] $ do
952 { core_binds <- thing_inside
953 ; return (NonRec bndr' rhs' : core_binds) }}
955 do_one (IfaceRec pairs) thing_inside
956 = do { bndrs' <- mapM newExtCoreBndr bndrs
957 ; extendIfaceIdEnv bndrs' $ do
958 { rhss' <- mapM tcIfaceExpr rhss
959 ; core_binds <- thing_inside
960 ; return (Rec (bndrs' `zip` rhss') : core_binds) }}
962 (bndrs,rhss) = unzip pairs
966 %************************************************************************
970 %************************************************************************
973 tcIdDetails :: Type -> IfaceIdDetails -> IfL IdDetails
974 tcIdDetails _ IfVanillaId = return VanillaId
975 tcIdDetails ty IfDFunId
976 = return (DFunId (isNewTyCon (classTyCon cls)))
978 (_, cls, _) = tcSplitDFunTy ty
980 tcIdDetails _ (IfRecSelId tc naughty)
981 = do { tc' <- tcIfaceTyCon tc
982 ; return (RecSelId { sel_tycon = tc', sel_naughty = naughty }) }
984 tcIdInfo :: Bool -> Name -> Type -> IfaceIdInfo -> IfL IdInfo
985 tcIdInfo ignore_prags name ty info
986 | ignore_prags = return vanillaIdInfo
987 | otherwise = case info of
988 NoInfo -> return vanillaIdInfo
989 HasInfo info -> foldlM tcPrag init_info info
991 -- Set the CgInfo to something sensible but uninformative before
992 -- we start; default assumption is that it has CAFs
993 init_info = vanillaIdInfo
995 tcPrag :: IdInfo -> IfaceInfoItem -> IfL IdInfo
996 tcPrag info HsNoCafRefs = return (info `setCafInfo` NoCafRefs)
997 tcPrag info (HsArity arity) = return (info `setArityInfo` arity)
998 tcPrag info (HsStrictness str) = return (info `setStrictnessInfo` Just str)
999 tcPrag info (HsInline prag) = return (info `setInlinePragInfo` prag)
1001 -- The next two are lazy, so they don't transitively suck stuff in
1002 tcPrag info (HsUnfold lb if_unf)
1003 = do { unf <- tcUnfolding name ty info if_unf
1004 ; let info1 | lb = info `setOccInfo` nonRuleLoopBreaker
1006 ; return (info1 `setUnfoldingInfoLazily` unf) }
1010 tcUnfolding :: Name -> Type -> IdInfo -> IfaceUnfolding -> IfL Unfolding
1011 tcUnfolding name _ info (IfCoreUnfold stable if_expr)
1012 = do { mb_expr <- tcPragExpr name if_expr
1013 ; let unf_src = if stable then InlineStable else InlineRhs
1014 ; return (case mb_expr of
1015 Nothing -> NoUnfolding
1016 Just expr -> mkUnfolding unf_src
1017 True {- Top level -}
1018 is_bottoming expr) }
1020 -- Strictness should occur before unfolding!
1021 is_bottoming = case strictnessInfo info of
1022 Just sig -> isBottomingSig sig
1025 tcUnfolding name _ _ (IfCompulsory if_expr)
1026 = do { mb_expr <- tcPragExpr name if_expr
1027 ; return (case mb_expr of
1028 Nothing -> NoUnfolding
1029 Just expr -> mkCompulsoryUnfolding expr) }
1031 tcUnfolding name _ _ (IfInlineRule arity unsat_ok boring_ok if_expr)
1032 = do { mb_expr <- tcPragExpr name if_expr
1033 ; return (case mb_expr of
1034 Nothing -> NoUnfolding
1035 Just expr -> mkCoreUnfolding True InlineStable expr arity
1036 (UnfWhen unsat_ok boring_ok))
1039 tcUnfolding name ty info (IfWrapper arity wkr)
1040 = do { mb_wkr_id <- forkM_maybe doc (tcIfaceExtId wkr)
1041 ; us <- newUniqueSupply
1042 ; return (case mb_wkr_id of
1043 Nothing -> noUnfolding
1044 Just wkr_id -> make_inline_rule wkr_id us) }
1046 doc = text "Worker for" <+> ppr name
1048 make_inline_rule wkr_id us
1049 = mkWwInlineRule wkr_id
1050 (initUs_ us (mkWrapper ty strict_sig) wkr_id)
1053 -- Again we rely here on strictness info always appearing
1055 strict_sig = case strictnessInfo info of
1057 Nothing -> pprPanic "Worker info but no strictness for" (ppr wkr)
1059 tcUnfolding name dfun_ty _ (IfDFunUnfold ops)
1060 = do { mb_ops1 <- forkM_maybe doc $ mapM tcIfaceExpr ops
1061 ; return (case mb_ops1 of
1062 Nothing -> noUnfolding
1063 Just ops1 -> mkDFunUnfolding dfun_ty ops1) }
1065 doc = text "Class ops for dfun" <+> ppr name
1068 For unfoldings we try to do the job lazily, so that we never type check
1069 an unfolding that isn't going to be looked at.
1072 tcPragExpr :: Name -> IfaceExpr -> IfL (Maybe CoreExpr)
1073 tcPragExpr name expr
1074 = forkM_maybe doc $ do
1075 core_expr' <- tcIfaceExpr expr
1077 -- Check for type consistency in the unfolding
1078 ifDOptM Opt_DoCoreLinting $ do
1079 in_scope <- get_in_scope_ids
1080 case lintUnfolding noSrcLoc in_scope core_expr' of
1081 Nothing -> return ()
1082 Just fail_msg -> pprPanic "Iface Lint failure" (hang doc 2 fail_msg)
1086 doc = text "Unfolding of" <+> ppr name
1087 get_in_scope_ids -- Urgh; but just for linting
1089 do { env <- getGblEnv
1090 ; case if_rec_types env of {
1091 Nothing -> return [] ;
1092 Just (_, get_env) -> do
1093 { type_env <- get_env
1094 ; return (typeEnvIds type_env) }}}
1099 %************************************************************************
1101 Getting from Names to TyThings
1103 %************************************************************************
1106 tcIfaceGlobal :: Name -> IfL TyThing
1108 | Just thing <- wiredInNameTyThing_maybe name
1109 -- Wired-in things include TyCons, DataCons, and Ids
1110 = do { ifCheckWiredInThing thing; return thing }
1112 = do { env <- getGblEnv
1113 ; case if_rec_types env of { -- Note [Tying the knot]
1114 Just (mod, get_type_env)
1115 | nameIsLocalOrFrom mod name
1116 -> do -- It's defined in the module being compiled
1117 { type_env <- setLclEnv () get_type_env -- yuk
1118 ; case lookupNameEnv type_env name of
1119 Just thing -> return thing
1120 Nothing -> pprPanic "tcIfaceGlobal (local): not found:"
1121 (ppr name $$ ppr type_env) }
1125 { hsc_env <- getTopEnv
1126 ; mb_thing <- liftIO (lookupTypeHscEnv hsc_env name)
1127 ; case mb_thing of {
1128 Just thing -> return thing ;
1131 { mb_thing <- importDecl name -- It's imported; go get it
1133 Failed err -> failIfM err
1134 Succeeded thing -> return thing
1137 -- Note [Tying the knot]
1138 -- ~~~~~~~~~~~~~~~~~~~~~
1139 -- The if_rec_types field is used in two situations:
1141 -- a) Compiling M.hs, which indiretly imports Foo.hi, which mentions M.T
1142 -- Then we look up M.T in M's type environment, which is splatted into if_rec_types
1143 -- after we've built M's type envt.
1145 -- b) In ghc --make, during the upsweep, we encounter M.hs, whose interface M.hi
1146 -- is up to date. So we call typecheckIface on M.hi. This splats M.T into
1147 -- if_rec_types so that the (lazily typechecked) decls see all the other decls
1149 -- In case (b) it's important to do the if_rec_types check *before* looking in the HPT
1150 -- Because if M.hs also has M.hs-boot, M.T will *already be* in the HPT, but in its
1151 -- emasculated form (e.g. lacking data constructors).
1153 tcIfaceTyCon :: IfaceTyCon -> IfL TyCon
1154 tcIfaceTyCon IfaceIntTc = tcWiredInTyCon intTyCon
1155 tcIfaceTyCon IfaceBoolTc = tcWiredInTyCon boolTyCon
1156 tcIfaceTyCon IfaceCharTc = tcWiredInTyCon charTyCon
1157 tcIfaceTyCon IfaceListTc = tcWiredInTyCon listTyCon
1158 tcIfaceTyCon IfacePArrTc = tcWiredInTyCon parrTyCon
1159 tcIfaceTyCon (IfaceTupTc bx ar) = tcWiredInTyCon (tupleTyCon bx ar)
1160 tcIfaceTyCon (IfaceAnyTc kind) = do { tc_kind <- tcIfaceType kind
1161 ; tcWiredInTyCon (anyTyConOfKind tc_kind) }
1162 tcIfaceTyCon (IfaceTc name) = do { thing <- tcIfaceGlobal name
1163 ; return (check_tc (tyThingTyCon thing)) }
1166 | debugIsOn = case toIfaceTyCon tc of
1168 _ -> pprTrace "check_tc" (ppr tc) tc
1170 -- we should be okay just returning Kind constructors without extra loading
1171 tcIfaceTyCon IfaceLiftedTypeKindTc = return liftedTypeKindTyCon
1172 tcIfaceTyCon IfaceOpenTypeKindTc = return openTypeKindTyCon
1173 tcIfaceTyCon IfaceUnliftedTypeKindTc = return unliftedTypeKindTyCon
1174 tcIfaceTyCon IfaceArgTypeKindTc = return argTypeKindTyCon
1175 tcIfaceTyCon IfaceUbxTupleKindTc = return ubxTupleKindTyCon
1177 -- Even though we are in an interface file, we want to make
1178 -- sure the instances and RULES of this tycon are loaded
1179 -- Imagine: f :: Double -> Double
1180 tcWiredInTyCon :: TyCon -> IfL TyCon
1181 tcWiredInTyCon tc = do { ifCheckWiredInThing (ATyCon tc)
1184 tcIfaceClass :: Name -> IfL Class
1185 tcIfaceClass name = do { thing <- tcIfaceGlobal name
1186 ; return (tyThingClass thing) }
1188 tcIfaceDataCon :: Name -> IfL DataCon
1189 tcIfaceDataCon name = do { thing <- tcIfaceGlobal name
1191 ADataCon dc -> return dc
1192 _ -> pprPanic "tcIfaceExtDC" (ppr name$$ ppr thing) }
1194 tcIfaceExtId :: Name -> IfL Id
1195 tcIfaceExtId name = do { thing <- tcIfaceGlobal name
1197 AnId id -> return id
1198 _ -> pprPanic "tcIfaceExtId" (ppr name$$ ppr thing) }
1201 %************************************************************************
1205 %************************************************************************
1208 bindIfaceBndr :: IfaceBndr -> (CoreBndr -> IfL a) -> IfL a
1209 bindIfaceBndr (IfaceIdBndr (fs, ty)) thing_inside
1210 = do { name <- newIfaceName (mkVarOccFS fs)
1211 ; ty' <- tcIfaceType ty
1212 ; let id = mkLocalId name ty'
1213 ; extendIfaceIdEnv [id] (thing_inside id) }
1214 bindIfaceBndr (IfaceTvBndr bndr) thing_inside
1215 = bindIfaceTyVar bndr thing_inside
1217 bindIfaceBndrs :: [IfaceBndr] -> ([CoreBndr] -> IfL a) -> IfL a
1218 bindIfaceBndrs [] thing_inside = thing_inside []
1219 bindIfaceBndrs (b:bs) thing_inside
1220 = bindIfaceBndr b $ \ b' ->
1221 bindIfaceBndrs bs $ \ bs' ->
1222 thing_inside (b':bs')
1225 -----------------------
1226 tcIfaceLetBndr :: IfaceLetBndr -> IfL Id
1227 tcIfaceLetBndr (IfLetBndr fs ty info)
1228 = do { name <- newIfaceName (mkVarOccFS fs)
1229 ; ty' <- tcIfaceType ty
1231 NoInfo -> return (mkLocalId name ty')
1232 HasInfo i -> return (mkLocalIdWithInfo name ty' (tc_info i)) }
1234 -- Similar to tcIdInfo, but much simpler
1235 tc_info [] = vanillaIdInfo
1236 tc_info (HsInline p : i) = tc_info i `setInlinePragInfo` p
1237 tc_info (HsArity a : i) = tc_info i `setArityInfo` a
1238 tc_info (HsStrictness s : i) = tc_info i `setStrictnessInfo` Just s
1239 tc_info (other : i) = pprTrace "tcIfaceLetBndr: discarding unexpected IdInfo"
1240 (ppr other) (tc_info i)
1242 -----------------------
1243 newExtCoreBndr :: IfaceLetBndr -> IfL Id
1244 newExtCoreBndr (IfLetBndr var ty _) -- Ignoring IdInfo for now
1245 = do { mod <- getIfModule
1246 ; name <- newGlobalBinder mod (mkVarOccFS var) noSrcSpan
1247 ; ty' <- tcIfaceType ty
1248 ; return (mkLocalId name ty') }
1250 -----------------------
1251 bindIfaceTyVar :: IfaceTvBndr -> (TyVar -> IfL a) -> IfL a
1252 bindIfaceTyVar (occ,kind) thing_inside
1253 = do { name <- newIfaceName (mkTyVarOccFS occ)
1254 ; tyvar <- mk_iface_tyvar name kind
1255 ; extendIfaceTyVarEnv [tyvar] (thing_inside tyvar) }
1257 bindIfaceTyVars :: [IfaceTvBndr] -> ([TyVar] -> IfL a) -> IfL a
1258 bindIfaceTyVars bndrs thing_inside
1259 = do { names <- newIfaceNames (map mkTyVarOccFS occs)
1260 ; tyvars <- zipWithM mk_iface_tyvar names kinds
1261 ; extendIfaceTyVarEnv tyvars (thing_inside tyvars) }
1263 (occs,kinds) = unzip bndrs
1265 mk_iface_tyvar :: Name -> IfaceKind -> IfL TyVar
1266 mk_iface_tyvar name ifKind
1267 = do { kind <- tcIfaceType ifKind
1268 ; if isCoercionKind kind then
1269 return (Var.mkCoVar name kind)
1271 return (Var.mkTyVar name kind) }
1273 bindIfaceTyVars_AT :: [IfaceTvBndr] -> ([TyVar] -> IfL a) -> IfL a
1274 -- Used for type variable in nested associated data/type declarations
1275 -- where some of the type variables are already in scope
1276 -- class C a where { data T a b }
1277 -- Here 'a' is in scope when we look at the 'data T'
1278 bindIfaceTyVars_AT [] thing_inside
1280 bindIfaceTyVars_AT (b@(tv_occ,_) : bs) thing_inside
1281 = bindIfaceTyVars_AT bs $ \ bs' ->
1282 do { mb_tv <- lookupIfaceTyVar tv_occ
1284 Just b' -> thing_inside (b':bs')
1285 Nothing -> bindIfaceTyVar b $ \ b' ->
1286 thing_inside (b':bs') }