1 {-# OPTIONS -#include "Linker.h" #-}
2 -----------------------------------------------------------------------------
3 -- $Id: InteractiveUI.hs,v 1.193 2005/03/08 09:47:43 simonpj Exp $
5 -- GHC Interactive User Interface
7 -- (c) The GHC Team 2004
9 -----------------------------------------------------------------------------
10 module InteractiveUI (
11 interactiveUI, -- :: CmState -> [FilePath] -> IO ()
15 #include "HsVersions.h"
18 import HscTypes ( GhciMode(..) )
19 import IfaceSyn ( IfaceDecl(..), IfaceClassOp(..), IfaceConDecls(..),
20 IfaceConDecl(..), IfaceType,
21 pprIfaceDeclHead, pprParendIfaceType,
22 pprIfaceForAllPart, pprIfaceType )
23 import FunDeps ( pprFundeps )
26 import DriverUtil ( remove_spaces )
27 import Linker ( showLinkerState, linkPackages )
29 import Name ( Name, NamedThing(..) )
30 import OccName ( OccName, parenSymOcc, occNameUserString )
31 import BasicTypes ( StrictnessMark(..), defaultFixity, SuccessFlag(..) )
33 import CmdLineOpts ( DynFlags(..), DynFlag(..), dopt )
34 import Panic hiding ( showException )
36 import SrcLoc ( SrcLoc, isGoodSrcLoc )
38 #ifndef mingw32_HOST_OS
39 import DriverUtil( handle )
41 #if __GLASGOW_HASKELL__ > 504
47 import Control.Concurrent ( yield ) -- Used in readline loop
48 import System.Console.Readline as Readline
53 import Control.Exception as Exception
55 -- import Control.Concurrent
59 import Data.Int ( Int64 )
62 import System.Environment
63 import System.Exit ( exitWith, ExitCode(..) )
64 import System.Directory
66 import System.IO.Error as IO
68 import Control.Monad as Monad
69 import Foreign.StablePtr ( newStablePtr )
71 import GHC.Exts ( unsafeCoerce# )
72 import GHC.IOBase ( IOErrorType(InvalidArgument) )
74 import Data.IORef ( IORef, newIORef, readIORef, writeIORef )
76 import System.Posix.Internals ( setNonBlockingFD )
78 -----------------------------------------------------------------------------
82 " / _ \\ /\\ /\\/ __(_)\n"++
83 " / /_\\// /_/ / / | | GHC Interactive, version " ++ cProjectVersion ++ ", for Haskell 98.\n"++
84 "/ /_\\\\/ __ / /___| | http://www.haskell.org/ghc/\n"++
85 "\\____/\\/ /_/\\____/|_| Type :? for help.\n"
87 GLOBAL_VAR(commands, builtin_commands, [(String, String -> GHCi Bool)])
89 builtin_commands :: [(String, String -> GHCi Bool)]
91 ("add", keepGoingPaths addModule),
92 ("browse", keepGoing browseCmd),
93 ("cd", keepGoing changeDirectory),
94 ("def", keepGoing defineMacro),
95 ("help", keepGoing help),
96 ("?", keepGoing help),
97 ("info", keepGoing info),
98 ("load", keepGoingPaths loadModule),
99 ("module", keepGoing setContext),
100 ("reload", keepGoing reloadModule),
101 ("set", keepGoing setCmd),
102 ("show", keepGoing showCmd),
103 ("type", keepGoing typeOfExpr),
104 ("kind", keepGoing kindOfType),
105 ("unset", keepGoing unsetOptions),
106 ("undef", keepGoing undefineMacro),
110 keepGoing :: (String -> GHCi ()) -> (String -> GHCi Bool)
111 keepGoing a str = a str >> return False
113 keepGoingPaths :: ([FilePath] -> GHCi ()) -> (String -> GHCi Bool)
114 keepGoingPaths a str = a (toArgs str) >> return False
116 shortHelpText = "use :? for help.\n"
118 -- NOTE: spaces at the end of each line to workaround CPP/string gap bug.
120 " Commands available from the prompt:\n" ++
122 " <stmt> evaluate/run <stmt>\n" ++
123 " :add <filename> ... add module(s) to the current target set\n" ++
124 " :browse [*]<module> display the names defined by <module>\n" ++
125 " :cd <dir> change directory to <dir>\n" ++
126 " :def <cmd> <expr> define a command :<cmd>\n" ++
127 " :help, :? display this list of commands\n" ++
128 " :info [<name> ...] display information about the given names\n" ++
129 " :load <filename> ... load module(s) and their dependents\n" ++
130 " :module [+/-] [*]<mod> ... set the context for expression evaluation\n" ++
131 " :reload reload the current module set\n" ++
133 " :set <option> ... set options\n" ++
134 " :set args <arg> ... set the arguments returned by System.getArgs\n" ++
135 " :set prog <progname> set the value returned by System.getProgName\n" ++
137 " :show modules show the currently loaded modules\n" ++
138 " :show bindings show the current bindings made at the prompt\n" ++
140 " :type <expr> show the type of <expr>\n" ++
141 " :kind <type> show the kind of <type>\n" ++
142 " :undef <cmd> undefine user-defined command :<cmd>\n" ++
143 " :unset <option> ... unset options\n" ++
144 " :quit exit GHCi\n" ++
145 " :!<command> run the shell command <command>\n" ++
147 " Options for ':set' and ':unset':\n" ++
149 " +r revert top-level expressions after each evaluation\n" ++
150 " +s print timing/memory stats after each evaluation\n" ++
151 " +t print type after evaluation\n" ++
152 " -<flags> most GHC command line flags can also be set here\n" ++
153 " (eg. -v2, -fglasgow-exts, etc.)\n"
156 interactiveUI :: DynFlags -> [FilePath] -> Maybe String -> IO ()
157 interactiveUI dflags srcs maybe_expr = do
159 cmstate <- cmInit Interactive dflags;
161 -- HACK! If we happen to get into an infinite loop (eg the user
162 -- types 'let x=x in x' at the prompt), then the thread will block
163 -- on a blackhole, and become unreachable during GC. The GC will
164 -- detect that it is unreachable and send it the NonTermination
165 -- exception. However, since the thread is unreachable, everything
166 -- it refers to might be finalized, including the standard Handles.
167 -- This sounds like a bug, but we don't have a good solution right
174 hSetBuffering stdout NoBuffering
176 -- Initialise buffering for the *interpreted* I/O system
177 initInterpBuffering cmstate
179 -- We don't want the cmd line to buffer any input that might be
180 -- intended for the program, so unbuffer stdin.
181 hSetBuffering stdin NoBuffering
183 -- initial context is just the Prelude
184 cmstate <- cmSetContext cmstate [] ["Prelude"]
190 startGHCi (runGHCi srcs dflags maybe_expr)
191 GHCiState{ progname = "<interactive>",
198 Readline.resetTerminal Nothing
203 runGHCi :: [FilePath] -> DynFlags -> Maybe String -> GHCi ()
204 runGHCi paths dflags maybe_expr = do
205 read_dot_files <- io (readIORef v_Read_DotGHCi)
207 when (read_dot_files) $ do
210 exists <- io (doesFileExist file)
212 dir_ok <- io (checkPerms ".")
213 file_ok <- io (checkPerms file)
214 when (dir_ok && file_ok) $ do
215 either_hdl <- io (IO.try (openFile "./.ghci" ReadMode))
218 Right hdl -> fileLoop hdl False
220 when (read_dot_files) $ do
221 -- Read in $HOME/.ghci
222 either_dir <- io (IO.try (getEnv "HOME"))
226 cwd <- io (getCurrentDirectory)
227 when (dir /= cwd) $ do
228 let file = dir ++ "/.ghci"
229 ok <- io (checkPerms file)
231 either_hdl <- io (IO.try (openFile file ReadMode))
234 Right hdl -> fileLoop hdl False
236 -- Perform a :load for files given on the GHCi command line
237 when (not (null paths)) $
238 ghciHandle showException $
241 -- if verbosity is greater than 0, or we are connected to a
242 -- terminal, display the prompt in the interactive loop.
243 is_tty <- io (hIsTerminalDevice stdin)
244 let show_prompt = verbosity dflags > 0 || is_tty
248 -- enter the interactive loop
249 interactiveLoop is_tty show_prompt
251 -- just evaluate the expression we were given
256 io $ do when (verbosity dflags > 0) $ putStrLn "Leaving GHCi."
259 interactiveLoop is_tty show_prompt = do
260 -- Ignore ^C exceptions caught here
261 ghciHandleDyn (\e -> case e of
262 Interrupted -> ghciUnblock (interactiveLoop is_tty show_prompt)
263 _other -> return ()) $ do
265 -- read commands from stdin
269 else fileLoop stdin show_prompt
271 fileLoop stdin show_prompt
275 -- NOTE: We only read .ghci files if they are owned by the current user,
276 -- and aren't world writable. Otherwise, we could be accidentally
277 -- running code planted by a malicious third party.
279 -- Furthermore, We only read ./.ghci if . is owned by the current user
280 -- and isn't writable by anyone else. I think this is sufficient: we
281 -- don't need to check .. and ../.. etc. because "." always refers to
282 -- the same directory while a process is running.
284 checkPerms :: String -> IO Bool
286 #ifdef mingw32_HOST_OS
289 DriverUtil.handle (\_ -> return False) $ do
290 st <- getFileStatus name
292 if fileOwner st /= me then do
293 putStrLn $ "WARNING: " ++ name ++ " is owned by someone else, IGNORING!"
296 let mode = fileMode st
297 if (groupWriteMode == (mode `intersectFileModes` groupWriteMode))
298 || (otherWriteMode == (mode `intersectFileModes` otherWriteMode))
300 putStrLn $ "*** WARNING: " ++ name ++
301 " is writable by someone else, IGNORING!"
306 fileLoop :: Handle -> Bool -> GHCi ()
307 fileLoop hdl prompt = do
308 cmstate <- getCmState
309 (mod,imports) <- io (cmGetContext cmstate)
310 when prompt (io (putStr (mkPrompt mod imports)))
311 l <- io (IO.try (hGetLine hdl))
313 Left e | isEOFError e -> return ()
314 | InvalidArgument <- etype -> return ()
315 | otherwise -> io (ioError e)
316 where etype = ioeGetErrorType e
317 -- treat InvalidArgument in the same way as EOF:
318 -- this can happen if the user closed stdin, or
319 -- perhaps did getContents which closes stdin at
322 case remove_spaces l of
323 "" -> fileLoop hdl prompt
324 l -> do quit <- runCommand l
325 if quit then return () else fileLoop hdl prompt
327 stringLoop :: [String] -> GHCi ()
328 stringLoop [] = return ()
329 stringLoop (s:ss) = do
330 case remove_spaces s of
332 l -> do quit <- runCommand l
333 if quit then return () else stringLoop ss
335 mkPrompt toplevs exports
336 = concat (intersperse " " (map ('*':) toplevs ++ exports)) ++ "> "
339 readlineLoop :: GHCi ()
341 cmstate <- getCmState
342 (mod,imports) <- io (cmGetContext cmstate)
344 l <- io (readline (mkPrompt mod imports)
345 `finally` setNonBlockingFD 0)
346 -- readline sometimes puts stdin into blocking mode,
347 -- so we need to put it back for the IO library
351 case remove_spaces l of
356 if quit then return () else readlineLoop
359 runCommand :: String -> GHCi Bool
360 runCommand c = ghciHandle handler (doCommand c)
362 -- This version is for the GHC command-line option -e. The only difference
363 -- from runCommand is that it catches the ExitException exception and
364 -- exits, rather than printing out the exception.
365 runCommandEval c = ghciHandle handleEval (doCommand c)
367 handleEval (ExitException code) = io (exitWith code)
368 handleEval e = do showException e
369 io (exitWith (ExitFailure 1))
371 -- This is the exception handler for exceptions generated by the
372 -- user's code; it normally just prints out the exception. The
373 -- handler must be recursive, in case showing the exception causes
374 -- more exceptions to be raised.
376 -- Bugfix: if the user closed stdout or stderr, the flushing will fail,
377 -- raising another exception. We therefore don't put the recursive
378 -- handler arond the flushing operation, so if stderr is closed
379 -- GHCi will just die gracefully rather than going into an infinite loop.
380 handler :: Exception -> GHCi Bool
381 handler exception = do
383 io installSignalHandlers
384 ghciHandle handler (showException exception >> return False)
386 showException (DynException dyn) =
387 case fromDynamic dyn of
388 Nothing -> io (putStrLn ("*** Exception: (unknown)"))
389 Just Interrupted -> io (putStrLn "Interrupted.")
390 Just (CmdLineError s) -> io (putStrLn s) -- omit the location for CmdLineError
391 Just ph@PhaseFailed{} -> io (putStrLn (showGhcException ph "")) -- ditto
392 Just other_ghc_ex -> io (print other_ghc_ex)
394 showException other_exception
395 = io (putStrLn ("*** Exception: " ++ show other_exception))
397 doCommand (':' : command) = specialCommand command
399 = do timeIt (do nms <- runStmt stmt; finishEvalExpr nms)
402 runStmt :: String -> GHCi [Name]
404 | null (filter (not.isSpace) stmt) = return []
406 = do st <- getGHCiState
407 cmstate <- getCmState
408 (new_cmstate, result) <-
409 io $ withProgName (progname st) $ withArgs (args st) $
410 cmRunStmt cmstate stmt
411 setGHCiState st{cmstate = new_cmstate}
413 CmRunFailed -> return []
414 CmRunException e -> throw e -- this is caught by runCommand(Eval)
415 CmRunOk names -> return names
417 -- possibly print the type and revert CAFs after evaluating an expression
419 = do b <- isOptionSet ShowType
420 cmstate <- getCmState
421 when b (mapM_ (showTypeOfName cmstate) names)
424 io installSignalHandlers
425 b <- isOptionSet RevertCAFs
426 io (when b revertCAFs)
429 showTypeOfName :: CmState -> Name -> GHCi ()
430 showTypeOfName cmstate n
431 = do maybe_str <- io (cmTypeOfName cmstate n)
434 Just str -> io (putStrLn (showSDoc (ppr n) ++ " :: " ++ str))
436 specialCommand :: String -> GHCi Bool
437 specialCommand ('!':str) = shellEscape (dropWhile isSpace str)
438 specialCommand str = do
439 let (cmd,rest) = break isSpace str
440 cmds <- io (readIORef commands)
441 case [ (s,f) | (s,f) <- cmds, prefixMatch cmd s ] of
442 [] -> io (hPutStr stdout ("unknown command ':" ++ cmd ++ "'\n"
443 ++ shortHelpText) >> return False)
444 [(_,f)] -> f (dropWhile isSpace rest)
445 cs -> io (hPutStrLn stdout ("prefix " ++ cmd ++
446 " matches multiple commands (" ++
447 foldr1 (\a b -> a ++ ',':b) (map fst cs)
448 ++ ")") >> return False)
450 noArgs c = throwDyn (CmdLineError ("command '" ++ c ++ "' takes no arguments"))
453 -----------------------------------------------------------------------------
454 -- To flush buffers for the *interpreted* computation we need
455 -- to refer to *its* stdout/stderr handles
457 GLOBAL_VAR(flush_interp, error "no flush_interp", IO ())
458 GLOBAL_VAR(turn_off_buffering, error "no flush_stdout", IO ())
460 no_buf_cmd = "System.IO.hSetBuffering System.IO.stdout System.IO.NoBuffering" ++
461 " Prelude.>> System.IO.hSetBuffering System.IO.stderr System.IO.NoBuffering"
462 flush_cmd = "System.IO.hFlush System.IO.stdout Prelude.>> System.IO.hFlush IO.stderr"
464 initInterpBuffering :: CmState -> IO ()
465 initInterpBuffering cmstate
466 = do maybe_hval <- cmCompileExpr cmstate no_buf_cmd
469 Just hval -> writeIORef turn_off_buffering (unsafeCoerce# hval :: IO ())
470 other -> panic "interactiveUI:setBuffering"
472 maybe_hval <- cmCompileExpr cmstate flush_cmd
474 Just hval -> writeIORef flush_interp (unsafeCoerce# hval :: IO ())
475 _ -> panic "interactiveUI:flush"
477 turnOffBuffering -- Turn it off right now
482 flushInterpBuffers :: GHCi ()
484 = io $ do Monad.join (readIORef flush_interp)
487 turnOffBuffering :: IO ()
489 = do Monad.join (readIORef turn_off_buffering)
492 -----------------------------------------------------------------------------
495 help :: String -> GHCi ()
496 help _ = io (putStr helpText)
498 info :: String -> GHCi ()
499 info "" = throwDyn (CmdLineError "syntax: ':i <thing-you-want-info-about>'")
500 info s = do { let names = words s
501 ; init_cms <- getCmState
502 ; dflags <- getDynFlags
503 ; let exts = dopt Opt_GlasgowExts dflags
504 ; mapM_ (infoThing exts init_cms) names }
506 infoThing exts cms name
507 = do { stuff <- io (cmGetInfo cms name)
508 ; io (putStrLn (showSDocForUser (cmGetPrintUnqual cms) $
509 vcat (intersperse (text "") (map (showThing exts) stuff)))) }
511 showThing :: Bool -> GetInfoResult -> SDoc
512 showThing exts (wanted_str, thing, fixity, src_loc, insts)
513 = vcat [ showWithLoc src_loc (showDecl exts want_name thing),
515 vcat (map show_inst insts)]
517 want_name occ = wanted_str == occNameUserString occ
520 | fix == defaultFixity = empty
521 | otherwise = ppr fix <+> text wanted_str
523 show_inst (inst_ty, loc)
524 = showWithLoc loc (ptext SLIT("instance") <+> ppr inst_ty)
526 showWithLoc :: SrcLoc -> SDoc -> SDoc
528 = hang doc 2 (char '\t' <> show_loc loc)
529 -- The tab tries to make them line up a bit
531 show_loc loc -- The ppr function for SrcLocs is a bit wonky
532 | isGoodSrcLoc loc = comment <+> ptext SLIT("Defined at") <+> ppr loc
533 | otherwise = comment <+> ppr loc
534 comment = ptext SLIT("--")
537 -- Now there is rather a lot of goop just to print declarations in a
538 -- civilised way with "..." for the parts we are less interested in.
540 showDecl :: Bool -> (OccName -> Bool) -> IfaceDecl -> SDoc
541 showDecl exts want_name (IfaceForeign {ifName = tc})
542 = ppr tc <+> ptext SLIT("is a foreign type")
544 showDecl exts want_name (IfaceId {ifName = var, ifType = ty})
545 = ppr var <+> dcolon <+> showType exts ty
547 showDecl exts want_name (IfaceSyn {ifName = tycon, ifTyVars = tyvars, ifSynRhs = mono_ty})
548 = hang (ptext SLIT("type") <+> pprIfaceDeclHead [] tycon tyvars)
549 2 (equals <+> ppr mono_ty)
551 showDecl exts want_name (IfaceData {ifName = tycon,
552 ifTyVars = tyvars, ifCons = condecls})
553 = hang (pp_nd <+> pprIfaceDeclHead context tycon tyvars)
554 2 (add_bars (ppr_trim show_con cs))
556 show_con (IfVanillaCon { ifConOcc = con_name, ifConInfix = is_infix, ifConArgTys = tys,
557 ifConStricts = strs, ifConFields = flds})
558 | want_name tycon || want_name con_name || any want_name flds
559 = Just (show_guts con_name is_infix tys_w_strs flds)
560 | otherwise = Nothing
562 tys_w_strs = tys `zip` (strs ++ repeat NotMarkedStrict)
563 show_con (IfGadtCon { ifConOcc = con_name, ifConTyVars = tvs, ifConCtxt = theta,
564 ifConArgTys = arg_tys, ifConResTys = res_tys, ifConStricts = strs })
565 | want_name tycon || want_name con_name
566 = Just (ppr_bndr con_name <+> colon <+> pprIfaceForAllPart tvs theta pp_tau)
567 | otherwise = Nothing
569 tys_w_strs = arg_tys `zip` (strs ++ repeat NotMarkedStrict)
570 pp_tau = foldr add pp_res_ty tys_w_strs
571 pp_res_ty = ppr_bndr tycon <+> hsep (map pprParendIfaceType res_tys)
572 add bty pp_ty = ppr_bangty bty <+> arrow <+> pp_ty
574 show_guts con True [ty1, ty2] flds = sep [ppr_bangty ty1, ppr con, ppr_bangty ty2]
575 show_guts con _ tys [] = ppr_bndr con <+> sep (map ppr_bangty tys)
576 show_guts con _ tys flds
577 = ppr_bndr con <+> braces (sep (punctuate comma (ppr_trim show_fld (tys `zip` flds))))
579 show_fld (bty, fld) | want_name tycon || want_name con || want_name fld
580 = Just (ppr_bndr fld <+> dcolon <+> ppr_bangty bty)
581 | otherwise = Nothing
583 (pp_nd, context, cs) = case condecls of
584 IfAbstractTyCon -> (ptext SLIT("data"), [], [])
585 IfDataTyCon (Just cxt) cs -> (ptext SLIT("data"), cxt, cs)
586 IfDataTyCon Nothing cs -> (ptext SLIT("data"), [], cs)
587 IfNewTyCon c -> (ptext SLIT("newtype"), [], [c])
590 add_bars [c] = equals <+> c
591 add_bars (c:cs) = equals <+> sep (c : map (char '|' <+>) cs)
593 ppr_bangty (ty, str) = ppr_str str <> pprParendIfaceType ty
594 ppr_str MarkedStrict = char '!'
595 ppr_str MarkedUnboxed = ptext SLIT("!!")
596 ppr_str NotMarkedStrict = empty
598 showDecl exts want_name (IfaceClass {ifCtxt = context, ifName = clas, ifTyVars = tyvars,
599 ifFDs = fds, ifSigs = sigs})
600 = hang (ptext SLIT("class") <+> pprIfaceDeclHead context clas tyvars
601 <+> pprFundeps fds <+> opt_where)
602 2 (vcat (ppr_trim show_op sigs))
604 opt_where | null sigs = empty
605 | otherwise = ptext SLIT("where")
606 show_op (IfaceClassOp op dm ty)
607 | want_name clas || want_name op
608 = Just (ppr_bndr op <+> dcolon <+> showType exts ty)
612 showType :: Bool -> IfaceType -> SDoc
613 showType True ty = pprIfaceType ty -- -fglasgow-exts: print with the foralls
614 showType False ty = ppr ty -- otherwise, print without the foralls
616 ppr_trim :: (a -> Maybe SDoc) -> [a] -> [SDoc]
618 = snd (foldr go (False, []) xs)
620 go x (eliding, so_far)
621 | Just doc <- show x = (False, doc : so_far)
622 | otherwise = if eliding then (True, so_far)
623 else (True, ptext SLIT("...") : so_far)
625 ppr_bndr :: OccName -> SDoc
626 -- Wrap operators in ()
627 ppr_bndr occ = parenSymOcc occ (ppr occ)
630 -----------------------------------------------------------------------------
633 addModule :: [FilePath] -> GHCi ()
635 state <- getGHCiState
636 io (revertCAFs) -- always revert CAFs on load/add.
637 files <- mapM expandPath files
638 let new_targets = files ++ targets state
639 graph <- io (cmDepAnal (cmstate state) new_targets)
640 (cmstate1, ok, mods) <- io (cmLoadModules (cmstate state) graph)
641 setGHCiState state{ cmstate = cmstate1, targets = new_targets }
642 setContextAfterLoad mods
643 dflags <- getDynFlags
644 modulesLoadedMsg ok mods dflags
646 changeDirectory :: String -> GHCi ()
647 changeDirectory dir = do
648 state <- getGHCiState
649 when (targets state /= []) $
650 io $ putStr "Warning: changing directory causes all loaded modules to be unloaded,\nbecause the search path has changed.\n"
651 cmstate1 <- io (cmUnload (cmstate state))
652 setGHCiState state{ cmstate = cmstate1, targets = [] }
653 setContextAfterLoad []
654 dir <- expandPath dir
655 io (setCurrentDirectory dir)
657 defineMacro :: String -> GHCi ()
659 let (macro_name, definition) = break isSpace s
660 cmds <- io (readIORef commands)
662 then throwDyn (CmdLineError "invalid macro name")
664 if (macro_name `elem` map fst cmds)
665 then throwDyn (CmdLineError
666 ("command '" ++ macro_name ++ "' is already defined"))
669 -- give the expression a type signature, so we can be sure we're getting
670 -- something of the right type.
671 let new_expr = '(' : definition ++ ") :: String -> IO String"
673 -- compile the expression
675 maybe_hv <- io (cmCompileExpr cms new_expr)
678 Just hv -> io (writeIORef commands --
679 ((macro_name, keepGoing (runMacro hv)) : cmds))
681 runMacro :: HValue{-String -> IO String-} -> String -> GHCi ()
683 str <- io ((unsafeCoerce# fun :: String -> IO String) s)
684 stringLoop (lines str)
686 undefineMacro :: String -> GHCi ()
687 undefineMacro macro_name = do
688 cmds <- io (readIORef commands)
689 if (macro_name `elem` map fst builtin_commands)
690 then throwDyn (CmdLineError
691 ("command '" ++ macro_name ++ "' cannot be undefined"))
693 if (macro_name `notElem` map fst cmds)
694 then throwDyn (CmdLineError
695 ("command '" ++ macro_name ++ "' not defined"))
697 io (writeIORef commands (filter ((/= macro_name) . fst) cmds))
700 loadModule :: [FilePath] -> GHCi ()
701 loadModule fs = timeIt (loadModule' fs)
703 loadModule' :: [FilePath] -> GHCi ()
704 loadModule' files = do
705 state <- getGHCiState
708 files <- mapM expandPath files
710 -- do the dependency anal first, so that if it fails we don't throw
711 -- away the current set of modules.
712 graph <- io (cmDepAnal (cmstate state) files)
714 -- Dependency anal ok, now unload everything
715 cmstate1 <- io (cmUnload (cmstate state))
716 setGHCiState state{ cmstate = cmstate1, targets = [] }
718 io (revertCAFs) -- always revert CAFs on load.
719 (cmstate2, ok, mods) <- io (cmLoadModules cmstate1 graph)
720 setGHCiState state{ cmstate = cmstate2, targets = files }
722 setContextAfterLoad mods
723 dflags <- getDynFlags
724 modulesLoadedMsg ok mods dflags
727 reloadModule :: String -> GHCi ()
729 state <- getGHCiState
730 case targets state of
731 [] -> io (putStr "no current target\n")
733 -- do the dependency anal first, so that if it fails we don't throw
734 -- away the current set of modules.
735 graph <- io (cmDepAnal (cmstate state) paths)
737 io (revertCAFs) -- always revert CAFs on reload.
739 <- io (cmLoadModules (cmstate state) graph)
740 setGHCiState state{ cmstate=cmstate1 }
741 setContextAfterLoad mods
742 dflags <- getDynFlags
743 modulesLoadedMsg ok mods dflags
745 reloadModule _ = noArgs ":reload"
747 setContextAfterLoad [] = setContext prel
748 setContextAfterLoad (m:_) = do
749 cmstate <- getCmState
750 b <- io (cmModuleIsInterpreted cmstate m)
751 if b then setContext ('*':m) else setContext m
753 modulesLoadedMsg ok mods dflags =
754 when (verbosity dflags > 0) $ do
756 | null mods = text "none."
758 punctuate comma (map text mods)) <> text "."
761 io (putStrLn (showSDoc (text "Failed, modules loaded: " <> mod_commas)))
763 io (putStrLn (showSDoc (text "Ok, modules loaded: " <> mod_commas)))
766 typeOfExpr :: String -> GHCi ()
768 = do cms <- getCmState
769 maybe_tystr <- io (cmTypeOfExpr cms str)
772 Just tystr -> io (putStrLn tystr)
774 kindOfType :: String -> GHCi ()
776 = do cms <- getCmState
777 maybe_tystr <- io (cmKindOfType cms str)
780 Just tystr -> io (putStrLn tystr)
782 quit :: String -> GHCi Bool
785 shellEscape :: String -> GHCi Bool
786 shellEscape str = io (system str >> return False)
788 -----------------------------------------------------------------------------
789 -- Browsing a module's contents
791 browseCmd :: String -> GHCi ()
794 ['*':m] | looksLikeModuleName m -> browseModule m False
795 [m] | looksLikeModuleName m -> browseModule m True
796 _ -> throwDyn (CmdLineError "syntax: :browse <module>")
798 browseModule m exports_only = do
801 is_interpreted <- io (cmModuleIsInterpreted cms m)
802 when (not is_interpreted && not exports_only) $
803 throwDyn (CmdLineError ("module '" ++ m ++ "' is not interpreted"))
805 -- Temporarily set the context to the module we're interested in,
806 -- just so we can get an appropriate PrintUnqualified
807 (as,bs) <- io (cmGetContext cms)
808 cms1 <- io (if exports_only then cmSetContext cms [] [prel,m]
809 else cmSetContext cms [m] [])
810 cms2 <- io (cmSetContext cms1 as bs)
812 things <- io (cmBrowseModule cms2 m exports_only)
814 let unqual = cmGetPrintUnqual cms1 -- NOTE: cms1 with the new context
816 dflags <- getDynFlags
817 let exts = dopt Opt_GlasgowExts dflags
818 io (putStrLn (showSDocForUser unqual (
819 vcat (map (showDecl exts (const True)) things)
822 -----------------------------------------------------------------------------
823 -- Setting the module context
826 | all sensible mods = fn mods
827 | otherwise = throwDyn (CmdLineError "syntax: :module [+/-] [*]M1 ... [*]Mn")
829 (fn, mods) = case str of
830 '+':stuff -> (addToContext, words stuff)
831 '-':stuff -> (removeFromContext, words stuff)
832 stuff -> (newContext, words stuff)
834 sensible ('*':m) = looksLikeModuleName m
835 sensible m = looksLikeModuleName m
839 (as,bs) <- separate cms mods [] []
840 let bs' = if null as && prel `notElem` bs then prel:bs else bs
841 cms' <- io (cmSetContext cms as bs')
844 separate cmstate [] as bs = return (as,bs)
845 separate cmstate (('*':m):ms) as bs = do
846 b <- io (cmModuleIsInterpreted cmstate m)
847 if b then separate cmstate ms (m:as) bs
848 else throwDyn (CmdLineError ("module '" ++ m ++ "' is not interpreted"))
849 separate cmstate (m:ms) as bs = separate cmstate ms as (m:bs)
854 addToContext mods = do
856 (as,bs) <- io (cmGetContext cms)
858 (as',bs') <- separate cms mods [] []
860 let as_to_add = as' \\ (as ++ bs)
861 bs_to_add = bs' \\ (as ++ bs)
863 cms' <- io (cmSetContext cms
864 (as ++ as_to_add) (bs ++ bs_to_add))
868 removeFromContext mods = do
870 (as,bs) <- io (cmGetContext cms)
872 (as_to_remove,bs_to_remove) <- separate cms mods [] []
874 let as' = as \\ (as_to_remove ++ bs_to_remove)
875 bs' = bs \\ (as_to_remove ++ bs_to_remove)
877 cms' <- io (cmSetContext cms as' bs')
880 ----------------------------------------------------------------------------
883 -- set options in the interpreter. Syntax is exactly the same as the
884 -- ghc command line, except that certain options aren't available (-C,
887 -- This is pretty fragile: most options won't work as expected. ToDo:
888 -- figure out which ones & disallow them.
890 setCmd :: String -> GHCi ()
892 = do st <- getGHCiState
893 let opts = options st
894 io $ putStrLn (showSDoc (
895 text "options currently set: " <>
898 else hsep (map (\o -> char '+' <> text (optToStr o)) opts)
902 ("args":args) -> setArgs args
903 ("prog":prog) -> setProg prog
904 wds -> setOptions wds
908 setGHCiState st{ args = args }
912 setGHCiState st{ progname = prog }
914 io (hPutStrLn stderr "syntax: :set prog <progname>")
917 do -- first, deal with the GHCi opts (+s, +t, etc.)
918 let (plus_opts, minus_opts) = partition isPlus wds
919 mapM_ setOpt plus_opts
921 -- now, the GHC flags
922 leftovers <- io $ processStaticFlags minus_opts
924 -- then, dynamic flags
925 dflags <- getDynFlags
926 (dflags',leftovers) <- io $ processDynamicFlags leftovers dflags
929 -- update things if the users wants more packages
931 let new_packages = pkgs_after \\ pkgs_before
932 when (not (null new_packages)) $
933 newPackages new_packages
936 if (not (null leftovers))
937 then throwDyn (CmdLineError ("unrecognised flags: " ++
942 unsetOptions :: String -> GHCi ()
944 = do -- first, deal with the GHCi opts (+s, +t, etc.)
946 (minus_opts, rest1) = partition isMinus opts
947 (plus_opts, rest2) = partition isPlus rest1
949 if (not (null rest2))
950 then io (putStrLn ("unknown option: '" ++ head rest2 ++ "'"))
953 mapM_ unsetOpt plus_opts
955 -- can't do GHC flags for now
956 if (not (null minus_opts))
957 then throwDyn (CmdLineError "can't unset GHC command-line flags")
960 isMinus ('-':s) = True
963 isPlus ('+':s) = True
967 = case strToGHCiOpt str of
968 Nothing -> io (putStrLn ("unknown option: '" ++ str ++ "'"))
969 Just o -> setOption o
972 = case strToGHCiOpt str of
973 Nothing -> io (putStrLn ("unknown option: '" ++ str ++ "'"))
974 Just o -> unsetOption o
976 strToGHCiOpt :: String -> (Maybe GHCiOption)
977 strToGHCiOpt "s" = Just ShowTiming
978 strToGHCiOpt "t" = Just ShowType
979 strToGHCiOpt "r" = Just RevertCAFs
980 strToGHCiOpt _ = Nothing
982 optToStr :: GHCiOption -> String
983 optToStr ShowTiming = "s"
984 optToStr ShowType = "t"
985 optToStr RevertCAFs = "r"
987 newPackages new_pkgs = do -- The new packages are already in v_Packages
988 state <- getGHCiState
989 cmstate1 <- io (cmUnload (cmstate state))
990 setGHCiState state{ cmstate = cmstate1, targets = [] }
991 dflags <- getDynFlags
992 io (linkPackages dflags new_pkgs)
993 setContextAfterLoad []
995 -- ---------------------------------------------------------------------------
1000 ["modules" ] -> showModules
1001 ["bindings"] -> showBindings
1002 ["linker"] -> io showLinkerState
1003 _ -> throwDyn (CmdLineError "syntax: :show [modules|bindings]")
1006 = do { cms <- getCmState
1007 ; let show_one ms = io (putStrLn (cmShowModule cms ms))
1008 ; mapM_ show_one (cmGetModuleGraph cms) }
1013 unqual = cmGetPrintUnqual cms
1014 -- showBinding b = putStrLn (showSDocForUser unqual (ppr (ifaceTyThing b)))
1015 showBinding b = putStrLn (showSDocForUser unqual (ppr (getName b)))
1017 io (mapM_ showBinding (cmGetBindings cms))
1021 -----------------------------------------------------------------------------
1024 data GHCiState = GHCiState
1028 targets :: [FilePath],
1030 options :: [GHCiOption]
1034 = ShowTiming -- show time/allocs after evaluation
1035 | ShowType -- show the type of expressions
1036 | RevertCAFs -- revert CAFs after every evaluation
1039 newtype GHCi a = GHCi { unGHCi :: IORef GHCiState -> IO a }
1041 startGHCi :: GHCi a -> GHCiState -> IO a
1042 startGHCi g state = do ref <- newIORef state; unGHCi g ref
1044 instance Monad GHCi where
1045 (GHCi m) >>= k = GHCi $ \s -> m s >>= \a -> unGHCi (k a) s
1046 return a = GHCi $ \s -> return a
1048 ghciHandleDyn :: Typeable t => (t -> GHCi a) -> GHCi a -> GHCi a
1049 ghciHandleDyn h (GHCi m) = GHCi $ \s ->
1050 Exception.catchDyn (m s) (\e -> unGHCi (h e) s)
1052 getGHCiState = GHCi $ \r -> readIORef r
1053 setGHCiState s = GHCi $ \r -> writeIORef r s
1055 -- for convenience...
1056 getCmState = getGHCiState >>= return . cmstate
1057 setCmState cms = do s <- getGHCiState; setGHCiState s{cmstate=cms}
1059 getDynFlags = getCmState >>= return . cmGetDFlags
1061 setDynFlags dflags = do s <- getCmState; setCmState (cmSetDFlags s dflags)
1063 isOptionSet :: GHCiOption -> GHCi Bool
1065 = do st <- getGHCiState
1066 return (opt `elem` options st)
1068 setOption :: GHCiOption -> GHCi ()
1070 = do st <- getGHCiState
1071 setGHCiState (st{ options = opt : filter (/= opt) (options st) })
1073 unsetOption :: GHCiOption -> GHCi ()
1075 = do st <- getGHCiState
1076 setGHCiState (st{ options = filter (/= opt) (options st) })
1078 io :: IO a -> GHCi a
1079 io m = GHCi { unGHCi = \s -> m >>= return }
1081 -----------------------------------------------------------------------------
1082 -- recursive exception handlers
1084 -- Don't forget to unblock async exceptions in the handler, or if we're
1085 -- in an exception loop (eg. let a = error a in a) the ^C exception
1086 -- may never be delivered. Thanks to Marcin for pointing out the bug.
1088 ghciHandle :: (Exception -> GHCi a) -> GHCi a -> GHCi a
1089 ghciHandle h (GHCi m) = GHCi $ \s ->
1090 Exception.catch (m s)
1091 (\e -> unGHCi (ghciUnblock (h e)) s)
1093 ghciUnblock :: GHCi a -> GHCi a
1094 ghciUnblock (GHCi a) = GHCi $ \s -> Exception.unblock (a s)
1096 -----------------------------------------------------------------------------
1097 -- timing & statistics
1099 timeIt :: GHCi a -> GHCi a
1101 = do b <- isOptionSet ShowTiming
1104 else do allocs1 <- io $ getAllocations
1105 time1 <- io $ getCPUTime
1107 allocs2 <- io $ getAllocations
1108 time2 <- io $ getCPUTime
1109 io $ printTimes (fromIntegral (allocs2 - allocs1))
1113 foreign import ccall unsafe "getAllocations" getAllocations :: IO Int64
1114 -- defined in ghc/rts/Stats.c
1116 printTimes :: Integer -> Integer -> IO ()
1117 printTimes allocs psecs
1118 = do let secs = (fromIntegral psecs / (10^12)) :: Float
1119 secs_str = showFFloat (Just 2) secs
1120 putStrLn (showSDoc (
1121 parens (text (secs_str "") <+> text "secs" <> comma <+>
1122 text (show allocs) <+> text "bytes")))
1124 -----------------------------------------------------------------------------
1131 -- Have to turn off buffering again, because we just
1132 -- reverted stdout, stderr & stdin to their defaults.
1134 foreign import ccall "revertCAFs" rts_revertCAFs :: IO ()
1135 -- Make it "safe", just in case
1137 -- -----------------------------------------------------------------------------
1140 expandPath :: String -> GHCi String
1142 case dropWhile isSpace path of
1144 tilde <- io (getEnv "HOME") -- will fail if HOME not defined
1145 return (tilde ++ '/':d)