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(..),
18 setContext, getContext,
19 nameSetToGlobalRdrEnv,
29 compileExpr, dynCompileExpr,
31 obtainTerm, obtainTerm1
37 #include "HsVersions.h"
39 import HscMain hiding (compileExpr)
42 import Type hiding (typeKind)
43 import TcType hiding (typeKind)
45 import Var hiding (setIdType)
48 import Name hiding ( varName )
65 import RtClosureInspect
76 import Control.Exception as Exception
77 import Control.Concurrent
79 import Foreign.StablePtr
81 -- -----------------------------------------------------------------------------
82 -- running a statement interactively
85 = RunOk [Name] -- ^ names bound by this evaluation
86 | RunFailed -- ^ statement failed compilation
87 | RunException Exception -- ^ statement raised an exception
88 | RunBreak ThreadId [Name] (Maybe BreakInfo)
91 = Break Bool HValue BreakInfo ThreadId
92 -- ^ the computation hit a breakpoint (Bool <=> was an exception)
93 | Complete (Either Exception [HValue])
94 -- ^ the computation completed with either an exception or a value
98 resumeStmt :: String, -- the original statement
99 resumeThreadId :: ThreadId, -- thread running the computation
100 resumeBreakMVar :: MVar (),
101 resumeStatMVar :: MVar Status,
102 resumeBindings :: ([Id], TyVarSet),
103 resumeFinalIds :: [Id], -- [Id] to bind on completion
104 resumeApStack :: HValue, -- The object from which we can get
105 -- value of the free variables.
106 resumeBreakInfo :: Maybe BreakInfo,
107 -- the breakpoint we stopped at
108 -- (Nothing <=> exception)
109 resumeSpan :: SrcSpan, -- just a cache, otherwise it's a pain
110 -- to fetch the ModDetails & ModBreaks
112 resumeHistory :: [History],
113 resumeHistoryIx :: Int -- 0 <==> at the top of the history
116 getResumeContext :: Session -> IO [Resume]
117 getResumeContext s = withSession s (return . ic_resume . hsc_IC)
124 isStep RunToCompletion = False
129 historyApStack :: HValue,
130 historyBreakInfo :: BreakInfo
133 getHistorySpan :: Session -> History -> IO SrcSpan
134 getHistorySpan s hist = withSession s $ \hsc_env -> do
135 let inf = historyBreakInfo hist
136 num = breakInfo_number inf
137 case lookupUFM (hsc_HPT hsc_env) (moduleName (breakInfo_module inf)) of
138 Just hmi -> return (modBreaks_locs (md_modBreaks (hm_details hmi)) ! num)
139 _ -> panic "getHistorySpan"
141 -- | Run a statement in the current interactive context. Statement
142 -- may bind multple values.
143 runStmt :: Session -> String -> SingleStep -> IO RunResult
144 runStmt (Session ref) expr step
146 hsc_env <- readIORef ref
148 breakMVar <- newEmptyMVar -- wait on this when we hit a breakpoint
149 statusMVar <- newEmptyMVar -- wait on this when a computation is running
151 -- Turn off -fwarn-unused-bindings when running a statement, to hide
152 -- warnings about the implicit bindings we introduce.
153 let dflags' = dopt_unset (hsc_dflags hsc_env) Opt_WarnUnusedBinds
154 hsc_env' = hsc_env{ hsc_dflags = dflags' }
156 maybe_stuff <- hscStmt hsc_env' expr
159 Nothing -> return RunFailed
160 Just (ids, hval) -> do
162 withBreakAction (isStep step) dflags' breakMVar statusMVar $ do
164 let thing_to_run = unsafeCoerce# hval :: IO [HValue]
165 status <- sandboxIO statusMVar thing_to_run
167 let ic = hsc_IC hsc_env
168 bindings = (ic_tmp_ids ic, ic_tyvars ic)
172 traceRunStatus expr ref bindings ids
173 breakMVar statusMVar status emptyHistory
175 handleRunStatus expr ref bindings ids
176 breakMVar statusMVar status emptyHistory
179 emptyHistory = nilBL 50 -- keep a log of length 50
181 handleRunStatus expr ref bindings final_ids breakMVar statusMVar status
184 -- did we hit a breakpoint or did we complete?
185 (Break is_exception apStack info tid) -> do
186 hsc_env <- readIORef ref
187 let mb_info | is_exception = Nothing
188 | otherwise = Just info
189 (hsc_env1, names, span) <- bindLocalsAtBreakpoint hsc_env
192 resume = Resume expr tid breakMVar statusMVar
193 bindings final_ids apStack mb_info span
195 hsc_env2 = pushResume hsc_env1 resume
197 writeIORef ref hsc_env2
198 return (RunBreak tid names mb_info)
199 (Complete either_hvals) ->
201 Left e -> return (RunException e)
203 hsc_env <- readIORef ref
204 let final_ic = extendInteractiveContext (hsc_IC hsc_env)
205 final_ids emptyVarSet
206 -- the bound Ids never have any free TyVars
207 final_names = map idName final_ids
208 writeIORef ref hsc_env{hsc_IC=final_ic}
209 Linker.extendLinkEnv (zip final_names hvals)
210 return (RunOk final_names)
213 traceRunStatus expr ref bindings final_ids
214 breakMVar statusMVar status history = do
215 hsc_env <- readIORef ref
217 -- when tracing, if we hit a breakpoint that is not explicitly
218 -- enabled, then we just log the event in the history and continue.
219 (Break is_exception apStack info tid) | not is_exception -> do
220 b <- isBreakEnabled hsc_env info
224 let history' = consBL (History apStack info) history
225 -- probably better make history strict here, otherwise
226 -- our BoundedList will be pointless.
228 status <- withBreakAction True (hsc_dflags hsc_env)
229 breakMVar statusMVar $ do
231 (do putMVar breakMVar () -- awaken the stopped thread
233 (takeMVar statusMVar) -- and wait for the result
234 traceRunStatus expr ref bindings final_ids
235 breakMVar statusMVar status history'
239 handle_normally = handleRunStatus expr ref bindings final_ids
240 breakMVar statusMVar status history
243 isBreakEnabled :: HscEnv -> BreakInfo -> IO Bool
244 isBreakEnabled hsc_env inf =
245 case lookupUFM (hsc_HPT hsc_env) (moduleName (breakInfo_module inf)) of
247 w <- getBreak (modBreaks_flags (md_modBreaks (hm_details hmi)))
248 (breakInfo_number inf)
249 case w of Just n -> return (n /= 0); _other -> return False
254 foreign import ccall "&rts_stop_next_breakpoint" stepFlag :: Ptr CInt
255 foreign import ccall "&rts_stop_on_exception" exceptionFlag :: Ptr CInt
257 setStepFlag = poke stepFlag 1
258 resetStepFlag = poke stepFlag 0
260 -- this points to the IO action that is executed when a breakpoint is hit
261 foreign import ccall "&rts_breakpoint_io_action"
262 breakPointIOAction :: Ptr (StablePtr (Bool -> BreakInfo -> HValue -> IO ()))
264 -- When running a computation, we redirect ^C exceptions to the running
265 -- thread. ToDo: we might want a way to continue even if the target
266 -- thread doesn't die when it receives the exception... "this thread
267 -- is not responding".
268 sandboxIO :: MVar Status -> IO [HValue] -> IO Status
269 sandboxIO statusMVar thing =
271 (forkIO (do res <- Exception.try thing
272 putMVar statusMVar (Complete res)))
273 (takeMVar statusMVar)
275 withInterruptsSentTo :: IO ThreadId -> IO r -> IO r
276 withInterruptsSentTo io get_result = do
277 ts <- takeMVar interruptTargetThread
279 putMVar interruptTargetThread (child:ts)
280 get_result `finally` modifyMVar_ interruptTargetThread (return.tail)
282 -- This function sets up the interpreter for catching breakpoints, and
283 -- resets everything when the computation has stopped running. This
284 -- is a not-very-good way to ensure that only the interactive
285 -- evaluation should generate breakpoints.
286 withBreakAction step dflags breakMVar statusMVar io
287 = bracket setBreakAction resetBreakAction (\_ -> io)
290 stablePtr <- newStablePtr onBreak
291 poke breakPointIOAction stablePtr
292 when (dopt Opt_BreakOnException dflags) $ poke exceptionFlag 1
293 when step $ setStepFlag
295 -- Breaking on exceptions is not enabled by default, since it
296 -- might be a bit surprising. The exception flag is turned off
297 -- as soon as it is hit, or in resetBreakAction below.
299 onBreak is_exception info apStack = do
301 putMVar statusMVar (Break is_exception apStack info tid)
304 resetBreakAction stablePtr = do
305 poke breakPointIOAction noBreakStablePtr
308 freeStablePtr stablePtr
310 noBreakStablePtr = unsafePerformIO $ newStablePtr noBreakAction
312 noBreakAction False info apStack = putStrLn "*** Ignoring breakpoint"
313 noBreakAction True info apStack = return () -- exception: just continue
315 resume :: Session -> SingleStep -> IO RunResult
316 resume (Session ref) step
318 hsc_env <- readIORef ref
319 let ic = hsc_IC hsc_env
320 resume = ic_resume ic
323 [] -> throwDyn (ProgramError "not stopped at a breakpoint")
325 -- unbind the temporary locals by restoring the TypeEnv from
326 -- before the breakpoint, and drop this Resume from the
327 -- InteractiveContext.
328 let (resume_tmp_ids, resume_tyvars) = resumeBindings r
329 ic' = ic { ic_tmp_ids = resume_tmp_ids,
330 ic_tyvars = resume_tyvars,
332 writeIORef ref hsc_env{ hsc_IC = ic' }
334 -- remove any bindings created since the breakpoint from the
335 -- linker's environment
336 let new_names = map idName (filter (`notElem` resume_tmp_ids)
338 Linker.deleteFromLinkEnv new_names
340 when (isStep step) $ setStepFlag
342 Resume expr tid breakMVar statusMVar bindings
343 final_ids apStack info _ _ _ -> do
344 withBreakAction (isStep step) (hsc_dflags hsc_env)
345 breakMVar statusMVar $ do
346 status <- withInterruptsSentTo
347 (do putMVar breakMVar ()
348 -- this awakens the stopped thread...
350 (takeMVar statusMVar)
351 -- and wait for the result
354 traceRunStatus expr ref bindings final_ids
355 breakMVar statusMVar status emptyHistory
357 handleRunStatus expr ref bindings final_ids
358 breakMVar statusMVar status emptyHistory
361 back :: Session -> IO ([Name], Int, SrcSpan)
364 forward :: Session -> IO ([Name], Int, SrcSpan)
365 forward = moveHist (subtract 1)
367 moveHist fn (Session ref) = do
368 hsc_env <- readIORef ref
369 case ic_resume (hsc_IC hsc_env) of
370 [] -> throwDyn (ProgramError "not stopped at a breakpoint")
372 let ix = resumeHistoryIx r
373 history = resumeHistory r
376 when (new_ix > length history) $
377 throwDyn (ProgramError "no more logged breakpoints")
379 throwDyn (ProgramError "already at the beginning of the history")
382 update_ic apStack mb_info = do
383 (hsc_env1, names, span) <- bindLocalsAtBreakpoint hsc_env
385 let ic = hsc_IC hsc_env1
386 r' = r { resumeHistoryIx = new_ix }
387 ic' = ic { ic_resume = r':rs }
389 writeIORef ref hsc_env1{ hsc_IC = ic' }
391 return (names, new_ix, span)
393 -- careful: we want apStack to be the AP_STACK itself, not a thunk
394 -- around it, hence the cases are carefully constructed below to
395 -- make this the case. ToDo: this is v. fragile, do something better.
398 Resume { resumeApStack = apStack,
399 resumeBreakInfo = mb_info } ->
400 update_ic apStack mb_info
401 else case history !! (new_ix - 1) of
402 History apStack info ->
403 update_ic apStack (Just info)
405 -- -----------------------------------------------------------------------------
406 -- After stopping at a breakpoint, add free variables to the environment
408 bindLocalsAtBreakpoint
412 -> IO (HscEnv, [Name], SrcSpan)
414 -- Nothing case: we stopped when an exception was raised, not at a
415 -- breakpoint. We have no location information or local variables to
416 -- bind, all we can do is bind a local variable to the exception
418 bindLocalsAtBreakpoint hsc_env apStack Nothing = do
419 let exn_fs = FSLIT("_exception")
420 exn_name = mkInternalName (getUnique exn_fs) (mkVarOccFS exn_fs) span
422 e_name = mkInternalName (getUnique e_fs) (mkTyVarOcc e_fs) span
423 e_tyvar = mkTcTyVar e_name liftedTypeKind (SkolemTv RuntimeUnkSkol)
424 exn_id = Id.mkGlobalId VanillaGlobal exn_name (mkTyVarTy e_tyvar)
426 new_tyvars = unitVarSet e_tyvar
428 ictxt0 = hsc_IC hsc_env
429 ictxt1 = extendInteractiveContext ictxt0 [exn_id] new_tyvars
431 span = mkGeneralSrcSpan FSLIT("<exception thrown>")
433 Linker.extendLinkEnv [(exn_name, unsafeCoerce# apStack)]
434 return (hsc_env{ hsc_IC = ictxt1 }, [exn_name], span)
436 -- Just case: we stopped at a breakpoint, we have information about the location
437 -- of the breakpoint and the free variables of the expression.
438 bindLocalsAtBreakpoint hsc_env apStack (Just info) = do
441 mod_name = moduleName (breakInfo_module info)
442 mod_details = fmap hm_details (lookupUFM (hsc_HPT hsc_env) mod_name)
443 breaks = md_modBreaks (expectJust "handlRunStatus" mod_details)
444 index = breakInfo_number info
445 vars = breakInfo_vars info
446 result_ty = breakInfo_resty info
447 occs = modBreaks_vars breaks ! index
448 span = modBreaks_locs breaks ! index
450 -- filter out any unboxed ids; we can't bind these at the prompt
451 let pointers = filter (\(id,_) -> isPointer id) vars
452 isPointer id | PtrRep <- idPrimRep id = True
455 let (ids, offsets) = unzip pointers
457 -- It might be that getIdValFromApStack fails, because the AP_STACK
458 -- has been accidentally evaluated, or something else has gone wrong.
459 -- So that we don't fall over in a heap when this happens, just don't
460 -- bind any free variables instead, and we emit a warning.
461 mb_hValues <- mapM (getIdValFromApStack apStack) offsets
462 let filtered_ids = [ id | (id, Just _) <- zip ids mb_hValues ]
463 when (any isNothing mb_hValues) $
464 debugTraceMsg (hsc_dflags hsc_env) 1 $
465 text "Warning: _result has been evaluated, some bindings have been lost"
467 new_ids <- zipWithM mkNewId occs filtered_ids
468 let names = map idName new_ids
470 -- make an Id for _result. We use the Unique of the FastString "_result";
471 -- we don't care about uniqueness here, because there will only be one
472 -- _result in scope at any time.
473 let result_fs = FSLIT("_result")
474 result_name = mkInternalName (getUnique result_fs)
475 (mkVarOccFS result_fs) span
476 result_id = Id.mkGlobalId VanillaGlobal result_name result_ty
479 -- for each Id we're about to bind in the local envt:
480 -- - skolemise the type variables in its type, so they can't
481 -- be randomly unified with other types. These type variables
482 -- can only be resolved by type reconstruction in RtClosureInspect
483 -- - tidy the type variables
484 -- - globalise the Id (Ids are supposed to be Global, apparently).
486 let all_ids | isPointer result_id = result_id : new_ids
487 | otherwise = new_ids
488 (id_tys, tyvarss) = mapAndUnzip (skolemiseTy.idType) all_ids
489 (_,tidy_tys) = tidyOpenTypes emptyTidyEnv id_tys
490 new_tyvars = unionVarSets tyvarss
491 final_ids = zipWith setIdType all_ids tidy_tys
493 let ictxt0 = hsc_IC hsc_env
494 ictxt1 = extendInteractiveContext ictxt0 final_ids new_tyvars
496 Linker.extendLinkEnv [ (name,hval) | (name, Just hval) <- zip names mb_hValues ]
497 Linker.extendLinkEnv [(result_name, unsafeCoerce# apStack)]
498 return (hsc_env{ hsc_IC = ictxt1 }, result_name:names, span)
500 mkNewId :: OccName -> Id -> IO Id
502 let uniq = idUnique id
503 loc = nameSrcSpan (idName id)
504 name = mkInternalName uniq occ loc
506 new_id = Id.mkGlobalId VanillaGlobal name ty (idInfo id)
509 skolemiseTy :: Type -> (Type, TyVarSet)
510 skolemiseTy ty = (substTy subst ty, mkVarSet new_tyvars)
511 where env = mkVarEnv (zip tyvars new_tyvar_tys)
512 subst = mkTvSubst emptyInScopeSet env
513 tyvars = varSetElems (tyVarsOfType ty)
514 new_tyvars = map skolemiseTyVar tyvars
515 new_tyvar_tys = map mkTyVarTy new_tyvars
517 skolemiseTyVar :: TyVar -> TyVar
518 skolemiseTyVar tyvar = mkTcTyVar (tyVarName tyvar) (tyVarKind tyvar)
519 (SkolemTv RuntimeUnkSkol)
521 getIdValFromApStack :: HValue -> Int -> IO (Maybe HValue)
522 getIdValFromApStack apStack (I# stackDepth) = do
523 case getApStackVal# apStack (stackDepth +# 1#) of
524 -- The +1 is magic! I don't know where it comes
525 -- from, but this makes things line up. --SDM
528 0# -> return Nothing -- AP_STACK not found
529 _ -> return (Just (unsafeCoerce# result))
531 pushResume :: HscEnv -> Resume -> HscEnv
532 pushResume hsc_env resume = hsc_env { hsc_IC = ictxt1 }
534 ictxt0 = hsc_IC hsc_env
535 ictxt1 = ictxt0 { ic_resume = resume : ic_resume ictxt0 }
537 -- -----------------------------------------------------------------------------
538 -- Abandoning a resume context
540 abandon :: Session -> IO Bool
541 abandon (Session ref) = do
542 hsc_env <- readIORef ref
543 let ic = hsc_IC hsc_env
544 resume = ic_resume ic
548 writeIORef ref hsc_env{ hsc_IC = ic { ic_resume = rs } }
552 abandonAll :: Session -> IO Bool
553 abandonAll (Session ref) = do
554 hsc_env <- readIORef ref
555 let ic = hsc_IC hsc_env
556 resume = ic_resume ic
560 writeIORef ref hsc_env{ hsc_IC = ic { ic_resume = [] } }
564 -- when abandoning a computation we have to
565 -- (a) kill the thread with an async exception, so that the
566 -- computation itself is stopped, and
567 -- (b) fill in the MVar. This step is necessary because any
568 -- thunks that were under evaluation will now be updated
569 -- with the partial computation, which still ends in takeMVar,
570 -- so any attempt to evaluate one of these thunks will block
571 -- unless we fill in the MVar.
572 -- See test break010.
573 abandon_ :: Resume -> IO ()
575 killThread (resumeThreadId r)
576 putMVar (resumeBreakMVar r) ()
578 -- -----------------------------------------------------------------------------
579 -- Bounded list, optimised for repeated cons
581 data BoundedList a = BL
582 {-# UNPACK #-} !Int -- length
583 {-# UNPACK #-} !Int -- bound
585 [a] -- right, list is (left ++ reverse right)
587 nilBL :: Int -> BoundedList a
588 nilBL bound = BL 0 bound [] []
590 consBL a (BL len bound left right)
591 | len < bound = BL (len+1) bound (a:left) right
592 | null right = BL len bound [a] $! tail (reverse left)
593 | otherwise = BL len bound (a:left) $! tail right
595 toListBL (BL _ _ left right) = left ++ reverse right
597 -- lenBL (BL len _ _ _) = len
599 -- -----------------------------------------------------------------------------
600 -- | Set the interactive evaluation context.
602 -- Setting the context doesn't throw away any bindings; the bindings
603 -- we've built up in the InteractiveContext simply move to the new
604 -- module. They always shadow anything in scope in the current context.
605 setContext :: Session
606 -> [Module] -- entire top level scope of these modules
607 -> [Module] -- exports only of these modules
609 setContext sess@(Session ref) toplev_mods export_mods = do
610 hsc_env <- readIORef ref
611 let old_ic = hsc_IC hsc_env
612 hpt = hsc_HPT hsc_env
614 export_env <- mkExportEnv hsc_env export_mods
615 toplev_envs <- mapM (mkTopLevEnv hpt) toplev_mods
616 let all_env = foldr plusGlobalRdrEnv export_env toplev_envs
617 writeIORef ref hsc_env{ hsc_IC = old_ic { ic_toplev_scope = toplev_mods,
618 ic_exports = export_mods,
619 ic_rn_gbl_env = all_env }}
621 -- Make a GlobalRdrEnv based on the exports of the modules only.
622 mkExportEnv :: HscEnv -> [Module] -> IO GlobalRdrEnv
623 mkExportEnv hsc_env mods = do
624 stuff <- mapM (getModuleExports hsc_env) mods
626 (_msgs, mb_name_sets) = unzip stuff
627 gres = [ nameSetToGlobalRdrEnv (availsToNameSet avails) (moduleName mod)
628 | (Just avails, mod) <- zip mb_name_sets mods ]
630 return $! foldr plusGlobalRdrEnv emptyGlobalRdrEnv gres
632 nameSetToGlobalRdrEnv :: NameSet -> ModuleName -> GlobalRdrEnv
633 nameSetToGlobalRdrEnv names mod =
634 mkGlobalRdrEnv [ GRE { gre_name = name, gre_par = NoParent, gre_prov = vanillaProv mod }
635 | name <- nameSetToList names ]
637 vanillaProv :: ModuleName -> Provenance
638 -- We're building a GlobalRdrEnv as if the user imported
639 -- all the specified modules into the global interactive module
640 vanillaProv mod_name = Imported [ImpSpec { is_decl = decl, is_item = ImpAll}]
642 decl = ImpDeclSpec { is_mod = mod_name, is_as = mod_name,
644 is_dloc = srcLocSpan interactiveSrcLoc }
646 mkTopLevEnv :: HomePackageTable -> Module -> IO GlobalRdrEnv
648 = case lookupUFM hpt (moduleName modl) of
649 Nothing -> throwDyn (ProgramError ("mkTopLevEnv: not a home module " ++
650 showSDoc (ppr modl)))
652 case mi_globals (hm_iface details) of
654 throwDyn (ProgramError ("mkTopLevEnv: not interpreted "
655 ++ showSDoc (ppr modl)))
656 Just env -> return env
658 -- | Get the interactive evaluation context, consisting of a pair of the
659 -- set of modules from which we take the full top-level scope, and the set
660 -- of modules from which we take just the exports respectively.
661 getContext :: Session -> IO ([Module],[Module])
662 getContext s = withSession s (\HscEnv{ hsc_IC=ic } ->
663 return (ic_toplev_scope ic, ic_exports ic))
665 -- | Returns 'True' if the specified module is interpreted, and hence has
666 -- its full top-level scope available.
667 moduleIsInterpreted :: Session -> Module -> IO Bool
668 moduleIsInterpreted s modl = withSession s $ \h ->
669 if modulePackageId modl /= thisPackage (hsc_dflags h)
671 else case lookupUFM (hsc_HPT h) (moduleName modl) of
672 Just details -> return (isJust (mi_globals (hm_iface details)))
673 _not_a_home_module -> return False
675 -- | Looks up an identifier in the current interactive context (for :info)
676 getInfo :: Session -> Name -> IO (Maybe (TyThing,Fixity,[Instance]))
677 getInfo s name = withSession s $ \hsc_env -> tcRnGetInfo hsc_env name
679 -- | Returns all names in scope in the current interactive context
680 getNamesInScope :: Session -> IO [Name]
681 getNamesInScope s = withSession s $ \hsc_env -> do
682 return (map gre_name (globalRdrEnvElts (ic_rn_gbl_env (hsc_IC hsc_env))))
684 getRdrNamesInScope :: Session -> IO [RdrName]
685 getRdrNamesInScope s = withSession s $ \hsc_env -> do
688 gbl_rdrenv = ic_rn_gbl_env ic
690 gbl_names = concat (map greToRdrNames (globalRdrEnvElts gbl_rdrenv))
691 lcl_names = map (mkRdrUnqual.nameOccName.idName) ids
693 return (gbl_names ++ lcl_names)
696 -- ToDo: move to RdrName
697 greToRdrNames :: GlobalRdrElt -> [RdrName]
698 greToRdrNames GRE{ gre_name = name, gre_prov = prov }
701 Imported specs -> concat (map do_spec (map is_decl specs))
703 occ = nameOccName name
706 | is_qual decl_spec = [qual]
707 | otherwise = [unqual,qual]
708 where qual = Qual (is_as decl_spec) occ
710 -- | Parses a string as an identifier, and returns the list of 'Name's that
711 -- the identifier can refer to in the current interactive context.
712 parseName :: Session -> String -> IO [Name]
713 parseName s str = withSession s $ \hsc_env -> do
714 maybe_rdr_name <- hscParseIdentifier (hsc_dflags hsc_env) str
715 case maybe_rdr_name of
717 Just (L _ rdr_name) -> do
718 mb_names <- tcRnLookupRdrName hsc_env rdr_name
722 -- ToDo: should return error messages
724 -- | Returns the 'TyThing' for a 'Name'. The 'Name' may refer to any
725 -- entity known to GHC, including 'Name's defined using 'runStmt'.
726 lookupName :: Session -> Name -> IO (Maybe TyThing)
727 lookupName s name = withSession s $ \hsc_env -> tcRnLookupName hsc_env name
729 -- -----------------------------------------------------------------------------
730 -- Getting the type of an expression
732 -- | Get the type of an expression
733 exprType :: Session -> String -> IO (Maybe Type)
734 exprType s expr = withSession s $ \hsc_env -> do
735 maybe_stuff <- hscTcExpr hsc_env expr
737 Nothing -> return Nothing
738 Just ty -> return (Just tidy_ty)
740 tidy_ty = tidyType emptyTidyEnv ty
742 -- -----------------------------------------------------------------------------
743 -- Getting the kind of a type
745 -- | Get the kind of a type
746 typeKind :: Session -> String -> IO (Maybe Kind)
747 typeKind s str = withSession s $ \hsc_env -> do
748 maybe_stuff <- hscKcType hsc_env str
750 Nothing -> return Nothing
751 Just kind -> return (Just kind)
753 -----------------------------------------------------------------------------
754 -- cmCompileExpr: compile an expression and deliver an HValue
756 compileExpr :: Session -> String -> IO (Maybe HValue)
757 compileExpr s expr = withSession s $ \hsc_env -> do
758 maybe_stuff <- hscStmt hsc_env ("let __cmCompileExpr = "++expr)
760 Nothing -> return Nothing
761 Just (ids, hval) -> do
763 hvals <- (unsafeCoerce# hval) :: IO [HValue]
766 ([n],[hv]) -> return (Just hv)
767 _ -> panic "compileExpr"
769 -- -----------------------------------------------------------------------------
770 -- Compile an expression into a dynamic
772 dynCompileExpr :: Session -> String -> IO (Maybe Dynamic)
773 dynCompileExpr ses expr = do
774 (full,exports) <- getContext ses
775 setContext ses full $
777 (stringToPackageId "base") (mkModuleName "Data.Dynamic")
779 let stmt = "let __dynCompileExpr = Data.Dynamic.toDyn (" ++ expr ++ ")"
780 res <- withSession ses (flip hscStmt stmt)
781 setContext ses full exports
783 Nothing -> return Nothing
784 Just (ids, hvals) -> do
785 vals <- (unsafeCoerce# hvals :: IO [Dynamic])
787 (_:[], v:[]) -> return (Just v)
788 _ -> panic "dynCompileExpr"
790 -----------------------------------------------------------------------------
791 -- show a module and it's source/object filenames
793 showModule :: Session -> ModSummary -> IO String
794 showModule s mod_summary = withSession s $ \hsc_env ->
795 isModuleInterpreted s mod_summary >>= \interpreted ->
796 return (showModMsg (hscTarget(hsc_dflags hsc_env)) interpreted mod_summary)
798 isModuleInterpreted :: Session -> ModSummary -> IO Bool
799 isModuleInterpreted s mod_summary = withSession s $ \hsc_env ->
800 case lookupUFM (hsc_HPT hsc_env) (ms_mod_name mod_summary) of
801 Nothing -> panic "missing linkable"
802 Just mod_info -> return (not obj_linkable)
804 obj_linkable = isObjectLinkable (expectJust "showModule" (hm_linkable mod_info))
806 obtainTerm1 :: Session -> Bool -> Maybe Type -> a -> IO Term
807 obtainTerm1 sess force mb_ty x = withSession sess $ \hsc_env -> cvObtainTerm hsc_env force mb_ty (unsafeCoerce# x)
809 obtainTerm :: Session -> Bool -> Id -> IO Term
810 obtainTerm sess force id = withSession sess $ \hsc_env -> do
811 hv <- Linker.getHValue hsc_env (varName id)
812 cvObtainTerm hsc_env force (Just$ idType id) hv