1 -- -----------------------------------------------------------------------------
3 -- (c) The University of Glasgow, 2005-2007
5 -- Running statements interactively
7 -- -----------------------------------------------------------------------------
9 module InteractiveEval (
11 RunResult(..), Status(..), Resume(..), History(..),
12 runStmt, SingleStep(..),
19 setContext, getContext,
20 nameSetToGlobalRdrEnv,
30 compileExpr, dynCompileExpr,
32 Term(..), obtainTerm, obtainTerm1, obtainTermB, reconstructType,
33 skolemiseSubst, skolemiseTy
39 #include "HsVersions.h"
41 import HscMain hiding (compileExpr)
44 import Type hiding (typeKind)
45 import TcType hiding (typeKind)
47 import Var hiding (setIdType)
50 import Name hiding ( varName )
67 import RtClosureInspect
73 import Data.List (find)
79 import Control.Exception as Exception
80 import Control.Concurrent
81 import Data.List (sortBy)
83 import Foreign.StablePtr
85 -- -----------------------------------------------------------------------------
86 -- running a statement interactively
89 = RunOk [Name] -- ^ names bound by this evaluation
90 | RunFailed -- ^ statement failed compilation
91 | RunException Exception -- ^ statement raised an exception
92 | RunBreak ThreadId [Name] (Maybe BreakInfo)
95 = Break Bool HValue BreakInfo ThreadId
96 -- ^ the computation hit a breakpoint (Bool <=> was an exception)
97 | Complete (Either Exception [HValue])
98 -- ^ the computation completed with either an exception or a value
102 resumeStmt :: String, -- the original statement
103 resumeThreadId :: ThreadId, -- thread running the computation
104 resumeBreakMVar :: MVar (),
105 resumeStatMVar :: MVar Status,
106 resumeBindings :: ([Id], TyVarSet),
107 resumeFinalIds :: [Id], -- [Id] to bind on completion
108 resumeApStack :: HValue, -- The object from which we can get
109 -- value of the free variables.
110 resumeBreakInfo :: Maybe BreakInfo,
111 -- the breakpoint we stopped at
112 -- (Nothing <=> exception)
113 resumeSpan :: SrcSpan, -- just a cache, otherwise it's a pain
114 -- to fetch the ModDetails & ModBreaks
116 resumeHistory :: [History],
117 resumeHistoryIx :: Int -- 0 <==> at the top of the history
120 getResumeContext :: Session -> IO [Resume]
121 getResumeContext s = withSession s (return . ic_resume . hsc_IC)
128 isStep RunToCompletion = False
133 historyApStack :: HValue,
134 historyBreakInfo :: BreakInfo,
135 historyEnclosingDecl :: Id
136 -- ^^ A cache of the enclosing top level declaration, for convenience
139 mkHistory :: HscEnv -> HValue -> BreakInfo -> History
140 mkHistory hsc_env hval bi = let
141 h = History hval bi decl
142 decl = findEnclosingDecl hsc_env (getHistoryModule h)
143 (getHistorySpan hsc_env h)
146 getHistoryModule :: History -> Module
147 getHistoryModule = breakInfo_module . historyBreakInfo
149 getHistorySpan :: HscEnv -> History -> SrcSpan
150 getHistorySpan hsc_env hist =
151 let inf = historyBreakInfo hist
152 num = breakInfo_number inf
153 in case lookupUFM (hsc_HPT hsc_env) (moduleName (breakInfo_module inf)) of
154 Just hmi -> modBreaks_locs (md_modBreaks (hm_details hmi)) ! num
155 _ -> panic "getHistorySpan"
157 -- | Finds the enclosing top level function name
158 findEnclosingDecl :: HscEnv -> Module -> SrcSpan -> Id
159 findEnclosingDecl hsc_env mod span =
160 case lookupUFM (hsc_HPT hsc_env) (moduleName mod) of
161 Nothing -> panic "findEnclosingDecl"
163 globals = typeEnvIds (md_types (hm_details hmi))
165 find (\id -> let n = idName id in
166 nameSrcSpan n < span && isExternalName n)
167 (reverse$ sortBy (compare `on` (nameSrcSpan.idName))
171 -- | Run a statement in the current interactive context. Statement
172 -- may bind multple values.
173 runStmt :: Session -> String -> SingleStep -> IO RunResult
174 runStmt (Session ref) expr step
176 hsc_env <- readIORef ref
178 breakMVar <- newEmptyMVar -- wait on this when we hit a breakpoint
179 statusMVar <- newEmptyMVar -- wait on this when a computation is running
181 -- Turn off -fwarn-unused-bindings when running a statement, to hide
182 -- warnings about the implicit bindings we introduce.
183 let dflags' = dopt_unset (hsc_dflags hsc_env) Opt_WarnUnusedBinds
184 hsc_env' = hsc_env{ hsc_dflags = dflags' }
186 maybe_stuff <- hscStmt hsc_env' expr
189 Nothing -> return RunFailed
190 Just (ids, hval) -> do
192 withBreakAction (isStep step) dflags' breakMVar statusMVar $ do
194 let thing_to_run = unsafeCoerce# hval :: IO [HValue]
195 status <- sandboxIO statusMVar thing_to_run
197 let ic = hsc_IC hsc_env
198 bindings = (ic_tmp_ids ic, ic_tyvars ic)
202 traceRunStatus expr ref bindings ids
203 breakMVar statusMVar status emptyHistory
205 handleRunStatus expr ref bindings ids
206 breakMVar statusMVar status emptyHistory
209 emptyHistory = nilBL 50 -- keep a log of length 50
211 handleRunStatus expr ref bindings final_ids breakMVar statusMVar status
214 -- did we hit a breakpoint or did we complete?
215 (Break is_exception apStack info tid) -> do
216 hsc_env <- readIORef ref
217 let mb_info | is_exception = Nothing
218 | otherwise = Just info
219 (hsc_env1, names, span) <- bindLocalsAtBreakpoint hsc_env
222 resume = Resume expr tid breakMVar statusMVar
223 bindings final_ids apStack mb_info span
225 hsc_env2 = pushResume hsc_env1 resume
227 writeIORef ref hsc_env2
228 return (RunBreak tid names mb_info)
229 (Complete either_hvals) ->
231 Left e -> return (RunException e)
233 hsc_env <- readIORef ref
234 let final_ic = extendInteractiveContext (hsc_IC hsc_env)
235 final_ids emptyVarSet
236 -- the bound Ids never have any free TyVars
237 final_names = map idName final_ids
238 Linker.extendLinkEnv (zip final_names hvals)
239 hsc_env' <- rttiEnvironment hsc_env{hsc_IC=final_ic}
240 writeIORef ref hsc_env'
241 return (RunOk final_names)
244 traceRunStatus expr ref bindings final_ids
245 breakMVar statusMVar status history = do
246 hsc_env <- readIORef ref
248 -- when tracing, if we hit a breakpoint that is not explicitly
249 -- enabled, then we just log the event in the history and continue.
250 (Break is_exception apStack info tid) | not is_exception -> do
251 b <- isBreakEnabled hsc_env info
255 let history' = mkHistory hsc_env apStack info `consBL` history
256 -- probably better make history strict here, otherwise
257 -- our BoundedList will be pointless.
259 status <- withBreakAction True (hsc_dflags hsc_env)
260 breakMVar statusMVar $ do
262 (do putMVar breakMVar () -- awaken the stopped thread
264 (takeMVar statusMVar) -- and wait for the result
265 traceRunStatus expr ref bindings final_ids
266 breakMVar statusMVar status history'
270 handle_normally = handleRunStatus expr ref bindings final_ids
271 breakMVar statusMVar status history
274 isBreakEnabled :: HscEnv -> BreakInfo -> IO Bool
275 isBreakEnabled hsc_env inf =
276 case lookupUFM (hsc_HPT hsc_env) (moduleName (breakInfo_module inf)) of
278 w <- getBreak (modBreaks_flags (md_modBreaks (hm_details hmi)))
279 (breakInfo_number inf)
280 case w of Just n -> return (n /= 0); _other -> return False
285 foreign import ccall "&rts_stop_next_breakpoint" stepFlag :: Ptr CInt
286 foreign import ccall "&rts_stop_on_exception" exceptionFlag :: Ptr CInt
288 setStepFlag = poke stepFlag 1
289 resetStepFlag = poke stepFlag 0
291 -- this points to the IO action that is executed when a breakpoint is hit
292 foreign import ccall "&rts_breakpoint_io_action"
293 breakPointIOAction :: Ptr (StablePtr (Bool -> BreakInfo -> HValue -> IO ()))
295 -- When running a computation, we redirect ^C exceptions to the running
296 -- thread. ToDo: we might want a way to continue even if the target
297 -- thread doesn't die when it receives the exception... "this thread
298 -- is not responding".
299 sandboxIO :: MVar Status -> IO [HValue] -> IO Status
300 sandboxIO statusMVar thing =
302 (forkIO (do res <- Exception.try (rethrow thing)
303 putMVar statusMVar (Complete res)))
304 (takeMVar statusMVar)
306 -- We want to turn ^C into a break when -fbreak-on-exception is on,
307 -- but it's an async exception and we only break for sync exceptions.
308 -- Idea: if we catch and re-throw it, then the re-throw will trigger
309 -- a break. Great - but we don't want to re-throw all exceptions, because
310 -- then we'll get a double break for ordinary sync exceptions (you'd have
311 -- to :continue twice, which looks strange). So if the exception is
312 -- not "Interrupted", we unset the exception flag before throwing.
314 rethrow :: IO a -> IO a
315 rethrow io = Exception.catch io $ \e -> -- NB. not catchDyn
317 DynException d | Just Interrupted <- fromDynamic d
318 -> Exception.throwIO e
319 _ -> do poke exceptionFlag 0; Exception.throwIO e
322 withInterruptsSentTo :: IO ThreadId -> IO r -> IO r
323 withInterruptsSentTo io get_result = do
324 ts <- takeMVar interruptTargetThread
326 putMVar interruptTargetThread (child:ts)
327 get_result `finally` modifyMVar_ interruptTargetThread (return.tail)
329 -- This function sets up the interpreter for catching breakpoints, and
330 -- resets everything when the computation has stopped running. This
331 -- is a not-very-good way to ensure that only the interactive
332 -- evaluation should generate breakpoints.
333 withBreakAction step dflags breakMVar statusMVar io
334 = bracket setBreakAction resetBreakAction (\_ -> io)
337 stablePtr <- newStablePtr onBreak
338 poke breakPointIOAction stablePtr
339 when (dopt Opt_BreakOnException dflags) $ poke exceptionFlag 1
340 when step $ setStepFlag
342 -- Breaking on exceptions is not enabled by default, since it
343 -- might be a bit surprising. The exception flag is turned off
344 -- as soon as it is hit, or in resetBreakAction below.
346 onBreak is_exception info apStack = do
348 putMVar statusMVar (Break is_exception apStack info tid)
351 resetBreakAction stablePtr = do
352 poke breakPointIOAction noBreakStablePtr
355 freeStablePtr stablePtr
357 noBreakStablePtr = unsafePerformIO $ newStablePtr noBreakAction
359 noBreakAction False info apStack = putStrLn "*** Ignoring breakpoint"
360 noBreakAction True info apStack = return () -- exception: just continue
362 resume :: Session -> SingleStep -> IO RunResult
363 resume (Session ref) step
365 hsc_env <- readIORef ref
366 let ic = hsc_IC hsc_env
367 resume = ic_resume ic
370 [] -> throwDyn (ProgramError "not stopped at a breakpoint")
372 -- unbind the temporary locals by restoring the TypeEnv from
373 -- before the breakpoint, and drop this Resume from the
374 -- InteractiveContext.
375 let (resume_tmp_ids, resume_tyvars) = resumeBindings r
376 ic' = ic { ic_tmp_ids = resume_tmp_ids,
377 ic_tyvars = resume_tyvars,
379 writeIORef ref hsc_env{ hsc_IC = ic' }
381 -- remove any bindings created since the breakpoint from the
382 -- linker's environment
383 let new_names = map idName (filter (`notElem` resume_tmp_ids)
385 Linker.deleteFromLinkEnv new_names
387 when (isStep step) $ setStepFlag
389 Resume expr tid breakMVar statusMVar bindings
390 final_ids apStack info _ hist _ -> do
391 withBreakAction (isStep step) (hsc_dflags hsc_env)
392 breakMVar statusMVar $ do
393 status <- withInterruptsSentTo
394 (do putMVar breakMVar ()
395 -- this awakens the stopped thread...
397 (takeMVar statusMVar)
398 -- and wait for the result
401 Nothing -> fromListBL 50 hist
402 Just i -> mkHistory hsc_env apStack i `consBL`
406 traceRunStatus expr ref bindings final_ids
407 breakMVar statusMVar status hist'
409 handleRunStatus expr ref bindings final_ids
410 breakMVar statusMVar status hist'
413 back :: Session -> IO ([Name], Int, SrcSpan)
416 forward :: Session -> IO ([Name], Int, SrcSpan)
417 forward = moveHist (subtract 1)
419 moveHist fn (Session ref) = do
420 hsc_env <- readIORef ref
421 case ic_resume (hsc_IC hsc_env) of
422 [] -> throwDyn (ProgramError "not stopped at a breakpoint")
424 let ix = resumeHistoryIx r
425 history = resumeHistory r
428 when (new_ix > length history) $
429 throwDyn (ProgramError "no more logged breakpoints")
431 throwDyn (ProgramError "already at the beginning of the history")
434 update_ic apStack mb_info = do
435 (hsc_env1, names, span) <- bindLocalsAtBreakpoint hsc_env
437 let ic = hsc_IC hsc_env1
438 r' = r { resumeHistoryIx = new_ix }
439 ic' = ic { ic_resume = r':rs }
441 writeIORef ref hsc_env1{ hsc_IC = ic' }
443 return (names, new_ix, span)
445 -- careful: we want apStack to be the AP_STACK itself, not a thunk
446 -- around it, hence the cases are carefully constructed below to
447 -- make this the case. ToDo: this is v. fragile, do something better.
450 Resume { resumeApStack = apStack,
451 resumeBreakInfo = mb_info } ->
452 update_ic apStack mb_info
453 else case history !! (new_ix - 1) of
454 History apStack info _ ->
455 update_ic apStack (Just info)
457 -- -----------------------------------------------------------------------------
458 -- After stopping at a breakpoint, add free variables to the environment
459 result_fs = FSLIT("_result")
461 bindLocalsAtBreakpoint
465 -> IO (HscEnv, [Name], SrcSpan)
467 -- Nothing case: we stopped when an exception was raised, not at a
468 -- breakpoint. We have no location information or local variables to
469 -- bind, all we can do is bind a local variable to the exception
471 bindLocalsAtBreakpoint hsc_env apStack Nothing = do
472 let exn_fs = FSLIT("_exception")
473 exn_name = mkInternalName (getUnique exn_fs) (mkVarOccFS exn_fs) span
475 e_name = mkInternalName (getUnique e_fs) (mkTyVarOcc e_fs) span
476 e_tyvar = mkTcTyVar e_name liftedTypeKind (SkolemTv RuntimeUnkSkol)
477 exn_id = Id.mkGlobalId VanillaGlobal exn_name (mkTyVarTy e_tyvar)
479 new_tyvars = unitVarSet e_tyvar
481 ictxt0 = hsc_IC hsc_env
482 ictxt1 = extendInteractiveContext ictxt0 [exn_id] new_tyvars
484 span = mkGeneralSrcSpan FSLIT("<exception thrown>")
486 Linker.extendLinkEnv [(exn_name, unsafeCoerce# apStack)]
487 return (hsc_env{ hsc_IC = ictxt1 }, [exn_name], span)
489 -- Just case: we stopped at a breakpoint, we have information about the location
490 -- of the breakpoint and the free variables of the expression.
491 bindLocalsAtBreakpoint hsc_env apStack (Just info) = do
494 mod_name = moduleName (breakInfo_module info)
495 mod_details = fmap hm_details (lookupUFM (hsc_HPT hsc_env) mod_name)
496 breaks = md_modBreaks (expectJust "handlRunStatus" mod_details)
497 index = breakInfo_number info
498 vars = breakInfo_vars info
499 result_ty = breakInfo_resty info
500 occs = modBreaks_vars breaks ! index
501 span = modBreaks_locs breaks ! index
503 -- filter out any unboxed ids; we can't bind these at the prompt
504 let pointers = filter (\(id,_) -> isPointer id) vars
505 isPointer id | PtrRep <- idPrimRep id = True
508 let (ids, offsets) = unzip pointers
510 -- It might be that getIdValFromApStack fails, because the AP_STACK
511 -- has been accidentally evaluated, or something else has gone wrong.
512 -- So that we don't fall over in a heap when this happens, just don't
513 -- bind any free variables instead, and we emit a warning.
514 mb_hValues <- mapM (getIdValFromApStack apStack) offsets
515 let filtered_ids = [ id | (id, Just hv) <- zip ids mb_hValues ]
516 when (any isNothing mb_hValues) $
517 debugTraceMsg (hsc_dflags hsc_env) 1 $
518 text "Warning: _result has been evaluated, some bindings have been lost"
520 new_ids <- zipWithM mkNewId occs filtered_ids
521 let names = map idName new_ids
523 -- make an Id for _result. We use the Unique of the FastString "_result";
524 -- we don't care about uniqueness here, because there will only be one
525 -- _result in scope at any time.
526 let result_name = mkInternalName (getUnique result_fs)
527 (mkVarOccFS result_fs) span
528 result_id = Id.mkGlobalId VanillaGlobal result_name result_ty
531 -- for each Id we're about to bind in the local envt:
532 -- - skolemise the type variables in its type, so they can't
533 -- be randomly unified with other types. These type variables
534 -- can only be resolved by type reconstruction in RtClosureInspect
535 -- - tidy the type variables
536 -- - globalise the Id (Ids are supposed to be Global, apparently).
538 let all_ids | isPointer result_id = result_id : new_ids
539 | otherwise = new_ids
540 (id_tys, tyvarss) = mapAndUnzip (skolemiseTy.idType) all_ids
541 (_,tidy_tys) = tidyOpenTypes emptyTidyEnv id_tys
542 new_tyvars = unionVarSets tyvarss
543 let final_ids = zipWith setIdType all_ids tidy_tys
544 ictxt0 = hsc_IC hsc_env
545 ictxt1 = extendInteractiveContext ictxt0 final_ids new_tyvars
546 Linker.extendLinkEnv [ (name,hval) | (name, Just hval) <- zip names mb_hValues ]
547 Linker.extendLinkEnv [(result_name, unsafeCoerce# apStack)]
548 hsc_env1 <- rttiEnvironment hsc_env{ hsc_IC = ictxt1 }
549 return (hsc_env1, result_name:names, span)
551 mkNewId :: OccName -> Id -> IO Id
553 let uniq = idUnique id
554 loc = nameSrcSpan (idName id)
555 name = mkInternalName uniq occ loc
557 new_id = Id.mkGlobalId VanillaGlobal name ty (idInfo id)
560 rttiEnvironment :: HscEnv -> IO HscEnv
561 rttiEnvironment hsc_env@HscEnv{hsc_IC=ic} = do
562 let InteractiveContext{ic_tmp_ids=tmp_ids} = ic
563 incompletelyTypedIds =
565 , not $ null [v | v <- varSetElems$ tyVarsOfType (idType id)
567 , (occNameFS.nameOccName.idName) id /= result_fs]
568 tys <- reconstructType hsc_env False `mapM` incompletelyTypedIds
569 -- map termType `fmap` (obtainTerm hsc_env False `mapM` incompletelyTypedIds)
571 let substs = [computeRTTIsubst ty ty'
572 | (ty, Just ty') <- zip (map idType incompletelyTypedIds) tys]
573 ic' = foldr (flip substInteractiveContext) ic
574 (map skolemiseSubst $ catMaybes substs)
575 return hsc_env{hsc_IC=ic'}
577 skolemiseSubst subst = subst `setTvSubstEnv`
578 mapVarEnv (fst.skolemiseTy) (getTvSubstEnv subst)
580 skolemiseTy :: Type -> (Type, TyVarSet)
581 skolemiseTy ty = (substTy subst ty, mkVarSet new_tyvars)
582 where env = mkVarEnv (zip tyvars new_tyvar_tys)
583 subst = mkTvSubst emptyInScopeSet env
584 tyvars = varSetElems (tyVarsOfType ty)
585 new_tyvars = map skolemiseTyVar tyvars
586 new_tyvar_tys = map mkTyVarTy new_tyvars
588 skolemiseTyVar :: TyVar -> TyVar
589 skolemiseTyVar tyvar = mkTcTyVar (tyVarName tyvar) (tyVarKind tyvar)
590 (SkolemTv RuntimeUnkSkol)
592 getIdValFromApStack :: HValue -> Int -> IO (Maybe HValue)
593 getIdValFromApStack apStack (I# stackDepth) = do
594 case getApStackVal# apStack (stackDepth +# 1#) of
595 -- The +1 is magic! I don't know where it comes
596 -- from, but this makes things line up. --SDM
599 0# -> return Nothing -- AP_STACK not found
600 _ -> return (Just (unsafeCoerce# result))
602 pushResume :: HscEnv -> Resume -> HscEnv
603 pushResume hsc_env resume = hsc_env { hsc_IC = ictxt1 }
605 ictxt0 = hsc_IC hsc_env
606 ictxt1 = ictxt0 { ic_resume = resume : ic_resume ictxt0 }
608 -- -----------------------------------------------------------------------------
609 -- Abandoning a resume context
611 abandon :: Session -> IO Bool
612 abandon (Session ref) = do
613 hsc_env <- readIORef ref
614 let ic = hsc_IC hsc_env
615 resume = ic_resume ic
619 writeIORef ref hsc_env{ hsc_IC = ic { ic_resume = rs } }
623 abandonAll :: Session -> IO Bool
624 abandonAll (Session ref) = do
625 hsc_env <- readIORef ref
626 let ic = hsc_IC hsc_env
627 resume = ic_resume ic
631 writeIORef ref hsc_env{ hsc_IC = ic { ic_resume = [] } }
635 -- when abandoning a computation we have to
636 -- (a) kill the thread with an async exception, so that the
637 -- computation itself is stopped, and
638 -- (b) fill in the MVar. This step is necessary because any
639 -- thunks that were under evaluation will now be updated
640 -- with the partial computation, which still ends in takeMVar,
641 -- so any attempt to evaluate one of these thunks will block
642 -- unless we fill in the MVar.
643 -- See test break010.
644 abandon_ :: Resume -> IO ()
646 killThread (resumeThreadId r)
647 putMVar (resumeBreakMVar r) ()
649 -- -----------------------------------------------------------------------------
650 -- Bounded list, optimised for repeated cons
652 data BoundedList a = BL
653 {-# UNPACK #-} !Int -- length
654 {-# UNPACK #-} !Int -- bound
656 [a] -- right, list is (left ++ reverse right)
658 nilBL :: Int -> BoundedList a
659 nilBL bound = BL 0 bound [] []
661 consBL a (BL len bound left right)
662 | len < bound = BL (len+1) bound (a:left) right
663 | null right = BL len bound [a] $! tail (reverse left)
664 | otherwise = BL len bound (a:left) $! tail right
666 toListBL (BL _ _ left right) = left ++ reverse right
668 fromListBL bound l = BL (length l) bound l []
670 -- lenBL (BL len _ _ _) = len
672 -- -----------------------------------------------------------------------------
673 -- | Set the interactive evaluation context.
675 -- Setting the context doesn't throw away any bindings; the bindings
676 -- we've built up in the InteractiveContext simply move to the new
677 -- module. They always shadow anything in scope in the current context.
678 setContext :: Session
679 -> [Module] -- entire top level scope of these modules
680 -> [Module] -- exports only of these modules
682 setContext sess@(Session ref) toplev_mods export_mods = do
683 hsc_env <- readIORef ref
684 let old_ic = hsc_IC hsc_env
685 hpt = hsc_HPT hsc_env
687 export_env <- mkExportEnv hsc_env export_mods
688 toplev_envs <- mapM (mkTopLevEnv hpt) toplev_mods
689 let all_env = foldr plusGlobalRdrEnv export_env toplev_envs
690 writeIORef ref hsc_env{ hsc_IC = old_ic { ic_toplev_scope = toplev_mods,
691 ic_exports = export_mods,
692 ic_rn_gbl_env = all_env }}
694 -- Make a GlobalRdrEnv based on the exports of the modules only.
695 mkExportEnv :: HscEnv -> [Module] -> IO GlobalRdrEnv
696 mkExportEnv hsc_env mods = do
697 stuff <- mapM (getModuleExports hsc_env) mods
699 (_msgs, mb_name_sets) = unzip stuff
700 gres = [ nameSetToGlobalRdrEnv (availsToNameSet avails) (moduleName mod)
701 | (Just avails, mod) <- zip mb_name_sets mods ]
703 return $! foldr plusGlobalRdrEnv emptyGlobalRdrEnv gres
705 nameSetToGlobalRdrEnv :: NameSet -> ModuleName -> GlobalRdrEnv
706 nameSetToGlobalRdrEnv names mod =
707 mkGlobalRdrEnv [ GRE { gre_name = name, gre_par = NoParent, gre_prov = vanillaProv mod }
708 | name <- nameSetToList names ]
710 vanillaProv :: ModuleName -> Provenance
711 -- We're building a GlobalRdrEnv as if the user imported
712 -- all the specified modules into the global interactive module
713 vanillaProv mod_name = Imported [ImpSpec { is_decl = decl, is_item = ImpAll}]
715 decl = ImpDeclSpec { is_mod = mod_name, is_as = mod_name,
717 is_dloc = srcLocSpan interactiveSrcLoc }
719 mkTopLevEnv :: HomePackageTable -> Module -> IO GlobalRdrEnv
721 = case lookupUFM hpt (moduleName modl) of
722 Nothing -> throwDyn (ProgramError ("mkTopLevEnv: not a home module " ++
723 showSDoc (ppr modl)))
725 case mi_globals (hm_iface details) of
727 throwDyn (ProgramError ("mkTopLevEnv: not interpreted "
728 ++ showSDoc (ppr modl)))
729 Just env -> return env
731 -- | Get the interactive evaluation context, consisting of a pair of the
732 -- set of modules from which we take the full top-level scope, and the set
733 -- of modules from which we take just the exports respectively.
734 getContext :: Session -> IO ([Module],[Module])
735 getContext s = withSession s (\HscEnv{ hsc_IC=ic } ->
736 return (ic_toplev_scope ic, ic_exports ic))
738 -- | Returns 'True' if the specified module is interpreted, and hence has
739 -- its full top-level scope available.
740 moduleIsInterpreted :: Session -> Module -> IO Bool
741 moduleIsInterpreted s modl = withSession s $ \h ->
742 if modulePackageId modl /= thisPackage (hsc_dflags h)
744 else case lookupUFM (hsc_HPT h) (moduleName modl) of
745 Just details -> return (isJust (mi_globals (hm_iface details)))
746 _not_a_home_module -> return False
748 -- | Looks up an identifier in the current interactive context (for :info)
749 -- Filter the instances by the ones whose tycons (or clases resp)
750 -- are in scope (qualified or otherwise). Otherwise we list a whole lot too many!
751 -- The exact choice of which ones to show, and which to hide, is a judgement call.
753 getInfo :: Session -> Name -> IO (Maybe (TyThing,Fixity,[Instance]))
755 = withSession s $ \hsc_env ->
756 do { mb_stuff <- tcRnGetInfo hsc_env name
758 Nothing -> return Nothing
759 Just (thing, fixity, ispecs) -> do
760 { let rdr_env = ic_rn_gbl_env (hsc_IC hsc_env)
761 ; return (Just (thing, fixity, filter (plausible rdr_env) ispecs)) } }
763 plausible rdr_env ispec -- Dfun involving only names that are in ic_rn_glb_env
764 = all ok $ nameSetToList $ tyClsNamesOfType $ idType $ instanceDFunId ispec
765 where -- A name is ok if it's in the rdr_env,
766 -- whether qualified or not
767 ok n | n == name = True -- The one we looked for in the first place!
768 | isBuiltInSyntax n = True
769 | isExternalName n = any ((== n) . gre_name)
770 (lookupGRE_Name rdr_env n)
773 -- | Returns all names in scope in the current interactive context
774 getNamesInScope :: Session -> IO [Name]
775 getNamesInScope s = withSession s $ \hsc_env -> do
776 return (map gre_name (globalRdrEnvElts (ic_rn_gbl_env (hsc_IC hsc_env))))
778 getRdrNamesInScope :: Session -> IO [RdrName]
779 getRdrNamesInScope s = withSession s $ \hsc_env -> do
782 gbl_rdrenv = ic_rn_gbl_env ic
784 gbl_names = concat (map greToRdrNames (globalRdrEnvElts gbl_rdrenv))
785 lcl_names = map (mkRdrUnqual.nameOccName.idName) ids
787 return (gbl_names ++ lcl_names)
790 -- ToDo: move to RdrName
791 greToRdrNames :: GlobalRdrElt -> [RdrName]
792 greToRdrNames GRE{ gre_name = name, gre_prov = prov }
795 Imported specs -> concat (map do_spec (map is_decl specs))
797 occ = nameOccName name
800 | is_qual decl_spec = [qual]
801 | otherwise = [unqual,qual]
802 where qual = Qual (is_as decl_spec) occ
804 -- | Parses a string as an identifier, and returns the list of 'Name's that
805 -- the identifier can refer to in the current interactive context.
806 parseName :: Session -> String -> IO [Name]
807 parseName s str = withSession s $ \hsc_env -> do
808 maybe_rdr_name <- hscParseIdentifier (hsc_dflags hsc_env) str
809 case maybe_rdr_name of
811 Just (L _ rdr_name) -> do
812 mb_names <- tcRnLookupRdrName hsc_env rdr_name
816 -- ToDo: should return error messages
818 -- | Returns the 'TyThing' for a 'Name'. The 'Name' may refer to any
819 -- entity known to GHC, including 'Name's defined using 'runStmt'.
820 lookupName :: Session -> Name -> IO (Maybe TyThing)
821 lookupName s name = withSession s $ \hsc_env -> tcRnLookupName hsc_env name
823 -- -----------------------------------------------------------------------------
824 -- Getting the type of an expression
826 -- | Get the type of an expression
827 exprType :: Session -> String -> IO (Maybe Type)
828 exprType s expr = withSession s $ \hsc_env -> do
829 maybe_stuff <- hscTcExpr hsc_env expr
831 Nothing -> return Nothing
832 Just ty -> return (Just tidy_ty)
834 tidy_ty = tidyType emptyTidyEnv ty
836 -- -----------------------------------------------------------------------------
837 -- Getting the kind of a type
839 -- | Get the kind of a type
840 typeKind :: Session -> String -> IO (Maybe Kind)
841 typeKind s str = withSession s $ \hsc_env -> do
842 maybe_stuff <- hscKcType hsc_env str
844 Nothing -> return Nothing
845 Just kind -> return (Just kind)
847 -----------------------------------------------------------------------------
848 -- cmCompileExpr: compile an expression and deliver an HValue
850 compileExpr :: Session -> String -> IO (Maybe HValue)
851 compileExpr s expr = withSession s $ \hsc_env -> do
852 maybe_stuff <- hscStmt hsc_env ("let __cmCompileExpr = "++expr)
854 Nothing -> return Nothing
855 Just (ids, hval) -> do
857 hvals <- (unsafeCoerce# hval) :: IO [HValue]
860 ([n],[hv]) -> return (Just hv)
861 _ -> panic "compileExpr"
863 -- -----------------------------------------------------------------------------
864 -- Compile an expression into a dynamic
866 dynCompileExpr :: Session -> String -> IO (Maybe Dynamic)
867 dynCompileExpr ses expr = do
868 (full,exports) <- getContext ses
869 setContext ses full $
871 (stringToPackageId "base") (mkModuleName "Data.Dynamic")
873 let stmt = "let __dynCompileExpr = Data.Dynamic.toDyn (" ++ expr ++ ")"
874 res <- withSession ses (flip hscStmt stmt)
875 setContext ses full exports
877 Nothing -> return Nothing
878 Just (ids, hvals) -> do
879 vals <- (unsafeCoerce# hvals :: IO [Dynamic])
881 (_:[], v:[]) -> return (Just v)
882 _ -> panic "dynCompileExpr"
884 -----------------------------------------------------------------------------
885 -- show a module and it's source/object filenames
887 showModule :: Session -> ModSummary -> IO String
888 showModule s mod_summary = withSession s $ \hsc_env ->
889 isModuleInterpreted s mod_summary >>= \interpreted ->
890 return (showModMsg (hscTarget(hsc_dflags hsc_env)) interpreted mod_summary)
892 isModuleInterpreted :: Session -> ModSummary -> IO Bool
893 isModuleInterpreted s mod_summary = withSession s $ \hsc_env ->
894 case lookupUFM (hsc_HPT hsc_env) (ms_mod_name mod_summary) of
895 Nothing -> panic "missing linkable"
896 Just mod_info -> return (not obj_linkable)
898 obj_linkable = isObjectLinkable (expectJust "showModule" (hm_linkable mod_info))
900 ----------------------------------------------------------------------------
903 obtainTerm1 :: HscEnv -> Bool -> Maybe Type -> a -> IO Term
904 obtainTerm1 hsc_env force mb_ty x =
905 cvObtainTerm hsc_env maxBound force mb_ty (unsafeCoerce# x)
907 obtainTermB :: HscEnv -> Int -> Bool -> Id -> IO Term
908 obtainTermB hsc_env bound force id = do
909 hv <- Linker.getHValue hsc_env (varName id)
910 cvObtainTerm hsc_env bound force (Just$ idType id) hv
912 obtainTerm :: HscEnv -> Bool -> Id -> IO Term
913 obtainTerm hsc_env force id = do
914 hv <- Linker.getHValue hsc_env (varName id)
915 cvObtainTerm hsc_env maxBound force (Just$ idType id) hv
917 -- Uses RTTI to reconstruct the type of an Id, making it less polymorphic
918 reconstructType :: HscEnv -> Bool -> Id -> IO (Maybe Type)
919 reconstructType hsc_env force id = do
920 hv <- Linker.getHValue hsc_env (varName id)
921 cvReconstructType hsc_env force (Just$ idType id) hv