1 {-# OPTIONS -#include "Linker.h" #-}
2 -----------------------------------------------------------------------------
3 -- $Id: InteractiveUI.hs,v 1.191 2005/02/25 13:07:10 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 IfaceInst(..), 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 (iface_inst, loc)
524 = showWithLoc loc (ptext SLIT("instance") <+> ppr (ifInstHead iface_inst))
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 <+> ptext SLIT("where"))
602 2 (vcat (ppr_trim show_op sigs))
604 show_op (IfaceClassOp op dm ty)
605 | want_name clas || want_name op
606 = Just (ppr_bndr op <+> dcolon <+> showType exts ty)
610 showType :: Bool -> IfaceType -> SDoc
611 showType True ty = pprIfaceType ty -- -fglasgow-exts: print with the foralls
612 showType False ty = ppr ty -- otherwise, print without the foralls
614 ppr_trim :: (a -> Maybe SDoc) -> [a] -> [SDoc]
616 = snd (foldr go (False, []) xs)
618 go x (eliding, so_far)
619 | Just doc <- show x = (False, doc : so_far)
620 | otherwise = if eliding then (True, so_far)
621 else (True, ptext SLIT("...") : so_far)
623 ppr_bndr :: OccName -> SDoc
624 -- Wrap operators in ()
625 ppr_bndr occ = parenSymOcc occ (ppr occ)
628 -----------------------------------------------------------------------------
631 addModule :: [FilePath] -> GHCi ()
633 state <- getGHCiState
634 io (revertCAFs) -- always revert CAFs on load/add.
635 files <- mapM expandPath files
636 let new_targets = files ++ targets state
637 graph <- io (cmDepAnal (cmstate state) new_targets)
638 (cmstate1, ok, mods) <- io (cmLoadModules (cmstate state) graph)
639 setGHCiState state{ cmstate = cmstate1, targets = new_targets }
640 setContextAfterLoad mods
641 dflags <- getDynFlags
642 modulesLoadedMsg ok mods dflags
644 changeDirectory :: String -> GHCi ()
645 changeDirectory dir = do
646 state <- getGHCiState
647 when (targets state /= []) $
648 io $ putStr "Warning: changing directory causes all loaded modules to be unloaded,\nbecause the search path has changed.\n"
649 cmstate1 <- io (cmUnload (cmstate state))
650 setGHCiState state{ cmstate = cmstate1, targets = [] }
651 setContextAfterLoad []
652 dir <- expandPath dir
653 io (setCurrentDirectory dir)
655 defineMacro :: String -> GHCi ()
657 let (macro_name, definition) = break isSpace s
658 cmds <- io (readIORef commands)
660 then throwDyn (CmdLineError "invalid macro name")
662 if (macro_name `elem` map fst cmds)
663 then throwDyn (CmdLineError
664 ("command '" ++ macro_name ++ "' is already defined"))
667 -- give the expression a type signature, so we can be sure we're getting
668 -- something of the right type.
669 let new_expr = '(' : definition ++ ") :: String -> IO String"
671 -- compile the expression
673 maybe_hv <- io (cmCompileExpr cms new_expr)
676 Just hv -> io (writeIORef commands --
677 ((macro_name, keepGoing (runMacro hv)) : cmds))
679 runMacro :: HValue{-String -> IO String-} -> String -> GHCi ()
681 str <- io ((unsafeCoerce# fun :: String -> IO String) s)
682 stringLoop (lines str)
684 undefineMacro :: String -> GHCi ()
685 undefineMacro macro_name = do
686 cmds <- io (readIORef commands)
687 if (macro_name `elem` map fst builtin_commands)
688 then throwDyn (CmdLineError
689 ("command '" ++ macro_name ++ "' cannot be undefined"))
691 if (macro_name `notElem` map fst cmds)
692 then throwDyn (CmdLineError
693 ("command '" ++ macro_name ++ "' not defined"))
695 io (writeIORef commands (filter ((/= macro_name) . fst) cmds))
698 loadModule :: [FilePath] -> GHCi ()
699 loadModule fs = timeIt (loadModule' fs)
701 loadModule' :: [FilePath] -> GHCi ()
702 loadModule' files = do
703 state <- getGHCiState
706 files <- mapM expandPath files
708 -- do the dependency anal first, so that if it fails we don't throw
709 -- away the current set of modules.
710 graph <- io (cmDepAnal (cmstate state) files)
712 -- Dependency anal ok, now unload everything
713 cmstate1 <- io (cmUnload (cmstate state))
714 setGHCiState state{ cmstate = cmstate1, targets = [] }
716 io (revertCAFs) -- always revert CAFs on load.
717 (cmstate2, ok, mods) <- io (cmLoadModules cmstate1 graph)
718 setGHCiState state{ cmstate = cmstate2, targets = files }
720 setContextAfterLoad mods
721 dflags <- getDynFlags
722 modulesLoadedMsg ok mods dflags
725 reloadModule :: String -> GHCi ()
727 state <- getGHCiState
728 case targets state of
729 [] -> io (putStr "no current target\n")
731 -- do the dependency anal first, so that if it fails we don't throw
732 -- away the current set of modules.
733 graph <- io (cmDepAnal (cmstate state) paths)
735 io (revertCAFs) -- always revert CAFs on reload.
737 <- io (cmLoadModules (cmstate state) graph)
738 setGHCiState state{ cmstate=cmstate1 }
739 setContextAfterLoad mods
740 dflags <- getDynFlags
741 modulesLoadedMsg ok mods dflags
743 reloadModule _ = noArgs ":reload"
745 setContextAfterLoad [] = setContext prel
746 setContextAfterLoad (m:_) = do
747 cmstate <- getCmState
748 b <- io (cmModuleIsInterpreted cmstate m)
749 if b then setContext ('*':m) else setContext m
751 modulesLoadedMsg ok mods dflags =
752 when (verbosity dflags > 0) $ do
754 | null mods = text "none."
756 punctuate comma (map text mods)) <> text "."
759 io (putStrLn (showSDoc (text "Failed, modules loaded: " <> mod_commas)))
761 io (putStrLn (showSDoc (text "Ok, modules loaded: " <> mod_commas)))
764 typeOfExpr :: String -> GHCi ()
766 = do cms <- getCmState
767 maybe_tystr <- io (cmTypeOfExpr cms str)
770 Just tystr -> io (putStrLn tystr)
772 kindOfType :: String -> GHCi ()
774 = do cms <- getCmState
775 maybe_tystr <- io (cmKindOfType cms str)
778 Just tystr -> io (putStrLn tystr)
780 quit :: String -> GHCi Bool
783 shellEscape :: String -> GHCi Bool
784 shellEscape str = io (system str >> return False)
786 -----------------------------------------------------------------------------
787 -- Browsing a module's contents
789 browseCmd :: String -> GHCi ()
792 ['*':m] | looksLikeModuleName m -> browseModule m False
793 [m] | looksLikeModuleName m -> browseModule m True
794 _ -> throwDyn (CmdLineError "syntax: :browse <module>")
796 browseModule m exports_only = do
799 is_interpreted <- io (cmModuleIsInterpreted cms m)
800 when (not is_interpreted && not exports_only) $
801 throwDyn (CmdLineError ("module '" ++ m ++ "' is not interpreted"))
803 -- Temporarily set the context to the module we're interested in,
804 -- just so we can get an appropriate PrintUnqualified
805 (as,bs) <- io (cmGetContext cms)
806 cms1 <- io (if exports_only then cmSetContext cms [] [prel,m]
807 else cmSetContext cms [m] [])
808 cms2 <- io (cmSetContext cms1 as bs)
810 things <- io (cmBrowseModule cms2 m exports_only)
812 let unqual = cmGetPrintUnqual cms1 -- NOTE: cms1 with the new context
814 dflags <- getDynFlags
815 let exts = dopt Opt_GlasgowExts dflags
816 io (putStrLn (showSDocForUser unqual (
817 vcat (map (showDecl exts (const True)) things)
820 -----------------------------------------------------------------------------
821 -- Setting the module context
824 | all sensible mods = fn mods
825 | otherwise = throwDyn (CmdLineError "syntax: :module [+/-] [*]M1 ... [*]Mn")
827 (fn, mods) = case str of
828 '+':stuff -> (addToContext, words stuff)
829 '-':stuff -> (removeFromContext, words stuff)
830 stuff -> (newContext, words stuff)
832 sensible ('*':m) = looksLikeModuleName m
833 sensible m = looksLikeModuleName m
837 (as,bs) <- separate cms mods [] []
838 let bs' = if null as && prel `notElem` bs then prel:bs else bs
839 cms' <- io (cmSetContext cms as bs')
842 separate cmstate [] as bs = return (as,bs)
843 separate cmstate (('*':m):ms) as bs = do
844 b <- io (cmModuleIsInterpreted cmstate m)
845 if b then separate cmstate ms (m:as) bs
846 else throwDyn (CmdLineError ("module '" ++ m ++ "' is not interpreted"))
847 separate cmstate (m:ms) as bs = separate cmstate ms as (m:bs)
852 addToContext mods = do
854 (as,bs) <- io (cmGetContext cms)
856 (as',bs') <- separate cms mods [] []
858 let as_to_add = as' \\ (as ++ bs)
859 bs_to_add = bs' \\ (as ++ bs)
861 cms' <- io (cmSetContext cms
862 (as ++ as_to_add) (bs ++ bs_to_add))
866 removeFromContext mods = do
868 (as,bs) <- io (cmGetContext cms)
870 (as_to_remove,bs_to_remove) <- separate cms mods [] []
872 let as' = as \\ (as_to_remove ++ bs_to_remove)
873 bs' = bs \\ (as_to_remove ++ bs_to_remove)
875 cms' <- io (cmSetContext cms as' bs')
878 ----------------------------------------------------------------------------
881 -- set options in the interpreter. Syntax is exactly the same as the
882 -- ghc command line, except that certain options aren't available (-C,
885 -- This is pretty fragile: most options won't work as expected. ToDo:
886 -- figure out which ones & disallow them.
888 setCmd :: String -> GHCi ()
890 = do st <- getGHCiState
891 let opts = options st
892 io $ putStrLn (showSDoc (
893 text "options currently set: " <>
896 else hsep (map (\o -> char '+' <> text (optToStr o)) opts)
900 ("args":args) -> setArgs args
901 ("prog":prog) -> setProg prog
902 wds -> setOptions wds
906 setGHCiState st{ args = args }
910 setGHCiState st{ progname = prog }
912 io (hPutStrLn stderr "syntax: :set prog <progname>")
915 do -- first, deal with the GHCi opts (+s, +t, etc.)
916 let (plus_opts, minus_opts) = partition isPlus wds
917 mapM_ setOpt plus_opts
919 -- now, the GHC flags
920 leftovers <- io $ processStaticFlags minus_opts
922 -- then, dynamic flags
923 dflags <- getDynFlags
924 (dflags',leftovers) <- io $ processDynamicFlags leftovers dflags
927 -- update things if the users wants more packages
929 let new_packages = pkgs_after \\ pkgs_before
930 when (not (null new_packages)) $
931 newPackages new_packages
934 if (not (null leftovers))
935 then throwDyn (CmdLineError ("unrecognised flags: " ++
940 unsetOptions :: String -> GHCi ()
942 = do -- first, deal with the GHCi opts (+s, +t, etc.)
944 (minus_opts, rest1) = partition isMinus opts
945 (plus_opts, rest2) = partition isPlus rest1
947 if (not (null rest2))
948 then io (putStrLn ("unknown option: '" ++ head rest2 ++ "'"))
951 mapM_ unsetOpt plus_opts
953 -- can't do GHC flags for now
954 if (not (null minus_opts))
955 then throwDyn (CmdLineError "can't unset GHC command-line flags")
958 isMinus ('-':s) = True
961 isPlus ('+':s) = True
965 = case strToGHCiOpt str of
966 Nothing -> io (putStrLn ("unknown option: '" ++ str ++ "'"))
967 Just o -> setOption o
970 = case strToGHCiOpt str of
971 Nothing -> io (putStrLn ("unknown option: '" ++ str ++ "'"))
972 Just o -> unsetOption o
974 strToGHCiOpt :: String -> (Maybe GHCiOption)
975 strToGHCiOpt "s" = Just ShowTiming
976 strToGHCiOpt "t" = Just ShowType
977 strToGHCiOpt "r" = Just RevertCAFs
978 strToGHCiOpt _ = Nothing
980 optToStr :: GHCiOption -> String
981 optToStr ShowTiming = "s"
982 optToStr ShowType = "t"
983 optToStr RevertCAFs = "r"
985 newPackages new_pkgs = do -- The new packages are already in v_Packages
986 state <- getGHCiState
987 cmstate1 <- io (cmUnload (cmstate state))
988 setGHCiState state{ cmstate = cmstate1, targets = [] }
989 dflags <- getDynFlags
990 io (linkPackages dflags new_pkgs)
991 setContextAfterLoad []
993 -- ---------------------------------------------------------------------------
998 ["modules" ] -> showModules
999 ["bindings"] -> showBindings
1000 ["linker"] -> io showLinkerState
1001 _ -> throwDyn (CmdLineError "syntax: :show [modules|bindings]")
1004 = do { cms <- getCmState
1005 ; let show_one ms = io (putStrLn (cmShowModule cms ms))
1006 ; mapM_ show_one (cmGetModuleGraph cms) }
1011 unqual = cmGetPrintUnqual cms
1012 -- showBinding b = putStrLn (showSDocForUser unqual (ppr (ifaceTyThing b)))
1013 showBinding b = putStrLn (showSDocForUser unqual (ppr (getName b)))
1015 io (mapM_ showBinding (cmGetBindings cms))
1019 -----------------------------------------------------------------------------
1022 data GHCiState = GHCiState
1026 targets :: [FilePath],
1028 options :: [GHCiOption]
1032 = ShowTiming -- show time/allocs after evaluation
1033 | ShowType -- show the type of expressions
1034 | RevertCAFs -- revert CAFs after every evaluation
1037 newtype GHCi a = GHCi { unGHCi :: IORef GHCiState -> IO a }
1039 startGHCi :: GHCi a -> GHCiState -> IO a
1040 startGHCi g state = do ref <- newIORef state; unGHCi g ref
1042 instance Monad GHCi where
1043 (GHCi m) >>= k = GHCi $ \s -> m s >>= \a -> unGHCi (k a) s
1044 return a = GHCi $ \s -> return a
1046 ghciHandleDyn :: Typeable t => (t -> GHCi a) -> GHCi a -> GHCi a
1047 ghciHandleDyn h (GHCi m) = GHCi $ \s ->
1048 Exception.catchDyn (m s) (\e -> unGHCi (h e) s)
1050 getGHCiState = GHCi $ \r -> readIORef r
1051 setGHCiState s = GHCi $ \r -> writeIORef r s
1053 -- for convenience...
1054 getCmState = getGHCiState >>= return . cmstate
1055 setCmState cms = do s <- getGHCiState; setGHCiState s{cmstate=cms}
1057 getDynFlags = getCmState >>= return . cmGetDFlags
1059 setDynFlags dflags = do s <- getCmState; setCmState (cmSetDFlags s dflags)
1061 isOptionSet :: GHCiOption -> GHCi Bool
1063 = do st <- getGHCiState
1064 return (opt `elem` options st)
1066 setOption :: GHCiOption -> GHCi ()
1068 = do st <- getGHCiState
1069 setGHCiState (st{ options = opt : filter (/= opt) (options st) })
1071 unsetOption :: GHCiOption -> GHCi ()
1073 = do st <- getGHCiState
1074 setGHCiState (st{ options = filter (/= opt) (options st) })
1076 io :: IO a -> GHCi a
1077 io m = GHCi { unGHCi = \s -> m >>= return }
1079 -----------------------------------------------------------------------------
1080 -- recursive exception handlers
1082 -- Don't forget to unblock async exceptions in the handler, or if we're
1083 -- in an exception loop (eg. let a = error a in a) the ^C exception
1084 -- may never be delivered. Thanks to Marcin for pointing out the bug.
1086 ghciHandle :: (Exception -> GHCi a) -> GHCi a -> GHCi a
1087 ghciHandle h (GHCi m) = GHCi $ \s ->
1088 Exception.catch (m s)
1089 (\e -> unGHCi (ghciUnblock (h e)) s)
1091 ghciUnblock :: GHCi a -> GHCi a
1092 ghciUnblock (GHCi a) = GHCi $ \s -> Exception.unblock (a s)
1094 -----------------------------------------------------------------------------
1095 -- timing & statistics
1097 timeIt :: GHCi a -> GHCi a
1099 = do b <- isOptionSet ShowTiming
1102 else do allocs1 <- io $ getAllocations
1103 time1 <- io $ getCPUTime
1105 allocs2 <- io $ getAllocations
1106 time2 <- io $ getCPUTime
1107 io $ printTimes (fromIntegral (allocs2 - allocs1))
1111 foreign import ccall unsafe "getAllocations" getAllocations :: IO Int64
1112 -- defined in ghc/rts/Stats.c
1114 printTimes :: Integer -> Integer -> IO ()
1115 printTimes allocs psecs
1116 = do let secs = (fromIntegral psecs / (10^12)) :: Float
1117 secs_str = showFFloat (Just 2) secs
1118 putStrLn (showSDoc (
1119 parens (text (secs_str "") <+> text "secs" <> comma <+>
1120 text (show allocs) <+> text "bytes")))
1122 -----------------------------------------------------------------------------
1129 -- Have to turn off buffering again, because we just
1130 -- reverted stdout, stderr & stdin to their defaults.
1132 foreign import ccall "revertCAFs" rts_revertCAFs :: IO ()
1133 -- Make it "safe", just in case
1135 -- -----------------------------------------------------------------------------
1138 expandPath :: String -> GHCi String
1140 case dropWhile isSpace path of
1142 tilde <- io (getEnv "HOME") -- will fail if HOME not defined
1143 return (tilde ++ '/':d)