1 {-# OPTIONS -#include "Linker.h" #-}
2 -----------------------------------------------------------------------------
3 -- $Id: InteractiveUI.hs,v 1.194 2005/03/18 13:38:31 simonmar 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 )
24 import Util ( removeSpaces )
25 import Linker ( showLinkerState, linkPackages )
27 import Name ( Name, NamedThing(..) )
28 import OccName ( OccName, parenSymOcc, occNameUserString )
29 import BasicTypes ( StrictnessMark(..), defaultFixity, SuccessFlag(..) )
31 import DynFlags ( DynFlags(..), DynFlag(..), dopt )
32 import Panic hiding ( showException )
34 import SrcLoc ( SrcLoc, isGoodSrcLoc )
36 #ifndef mingw32_HOST_OS
37 import Util ( handle )
39 #if __GLASGOW_HASKELL__ > 504
45 import Control.Concurrent ( yield ) -- Used in readline loop
46 import System.Console.Readline as Readline
51 import Control.Exception as Exception
53 -- import Control.Concurrent
57 import Data.Int ( Int64 )
60 import System.Environment
61 import System.Exit ( exitWith, ExitCode(..) )
62 import System.Directory
64 import System.IO.Error as IO
66 import Control.Monad as Monad
67 import Foreign.StablePtr ( newStablePtr )
69 import GHC.Exts ( unsafeCoerce# )
70 import GHC.IOBase ( IOErrorType(InvalidArgument) )
72 import Data.IORef ( IORef, newIORef, readIORef, writeIORef )
74 import System.Posix.Internals ( setNonBlockingFD )
76 -----------------------------------------------------------------------------
80 " / _ \\ /\\ /\\/ __(_)\n"++
81 " / /_\\// /_/ / / | | GHC Interactive, version " ++ cProjectVersion ++ ", for Haskell 98.\n"++
82 "/ /_\\\\/ __ / /___| | http://www.haskell.org/ghc/\n"++
83 "\\____/\\/ /_/\\____/|_| Type :? for help.\n"
85 GLOBAL_VAR(commands, builtin_commands, [(String, String -> GHCi Bool)])
87 builtin_commands :: [(String, String -> GHCi Bool)]
89 ("add", keepGoingPaths addModule),
90 ("browse", keepGoing browseCmd),
91 ("cd", keepGoing changeDirectory),
92 ("def", keepGoing defineMacro),
93 ("help", keepGoing help),
94 ("?", keepGoing help),
95 ("info", keepGoing info),
96 ("load", keepGoingPaths loadModule),
97 ("module", keepGoing setContext),
98 ("reload", keepGoing reloadModule),
99 ("set", keepGoing setCmd),
100 ("show", keepGoing showCmd),
101 ("type", keepGoing typeOfExpr),
102 ("kind", keepGoing kindOfType),
103 ("unset", keepGoing unsetOptions),
104 ("undef", keepGoing undefineMacro),
108 keepGoing :: (String -> GHCi ()) -> (String -> GHCi Bool)
109 keepGoing a str = a str >> return False
111 keepGoingPaths :: ([FilePath] -> GHCi ()) -> (String -> GHCi Bool)
112 keepGoingPaths a str = a (toArgs str) >> return False
114 shortHelpText = "use :? for help.\n"
116 -- NOTE: spaces at the end of each line to workaround CPP/string gap bug.
118 " Commands available from the prompt:\n" ++
120 " <stmt> evaluate/run <stmt>\n" ++
121 " :add <filename> ... add module(s) to the current target set\n" ++
122 " :browse [*]<module> display the names defined by <module>\n" ++
123 " :cd <dir> change directory to <dir>\n" ++
124 " :def <cmd> <expr> define a command :<cmd>\n" ++
125 " :help, :? display this list of commands\n" ++
126 " :info [<name> ...] display information about the given names\n" ++
127 " :load <filename> ... load module(s) and their dependents\n" ++
128 " :module [+/-] [*]<mod> ... set the context for expression evaluation\n" ++
129 " :reload reload the current module set\n" ++
131 " :set <option> ... set options\n" ++
132 " :set args <arg> ... set the arguments returned by System.getArgs\n" ++
133 " :set prog <progname> set the value returned by System.getProgName\n" ++
135 " :show modules show the currently loaded modules\n" ++
136 " :show bindings show the current bindings made at the prompt\n" ++
138 " :type <expr> show the type of <expr>\n" ++
139 " :kind <type> show the kind of <type>\n" ++
140 " :undef <cmd> undefine user-defined command :<cmd>\n" ++
141 " :unset <option> ... unset options\n" ++
142 " :quit exit GHCi\n" ++
143 " :!<command> run the shell command <command>\n" ++
145 " Options for ':set' and ':unset':\n" ++
147 " +r revert top-level expressions after each evaluation\n" ++
148 " +s print timing/memory stats after each evaluation\n" ++
149 " +t print type after evaluation\n" ++
150 " -<flags> most GHC command line flags can also be set here\n" ++
151 " (eg. -v2, -fglasgow-exts, etc.)\n"
154 interactiveUI :: DynFlags -> [FilePath] -> Maybe String -> IO ()
155 interactiveUI dflags srcs maybe_expr = do
157 cmstate <- cmInit Interactive dflags;
159 -- HACK! If we happen to get into an infinite loop (eg the user
160 -- types 'let x=x in x' at the prompt), then the thread will block
161 -- on a blackhole, and become unreachable during GC. The GC will
162 -- detect that it is unreachable and send it the NonTermination
163 -- exception. However, since the thread is unreachable, everything
164 -- it refers to might be finalized, including the standard Handles.
165 -- This sounds like a bug, but we don't have a good solution right
172 hSetBuffering stdout NoBuffering
174 -- Initialise buffering for the *interpreted* I/O system
175 initInterpBuffering cmstate
177 -- We don't want the cmd line to buffer any input that might be
178 -- intended for the program, so unbuffer stdin.
179 hSetBuffering stdin NoBuffering
181 -- initial context is just the Prelude
182 cmstate <- cmSetContext cmstate [] ["Prelude"]
188 startGHCi (runGHCi srcs dflags maybe_expr)
189 GHCiState{ progname = "<interactive>",
196 Readline.resetTerminal Nothing
201 runGHCi :: [FilePath] -> DynFlags -> Maybe String -> GHCi ()
202 runGHCi paths dflags maybe_expr = do
203 read_dot_files <- io (readIORef v_Read_DotGHCi)
205 when (read_dot_files) $ do
208 exists <- io (doesFileExist file)
210 dir_ok <- io (checkPerms ".")
211 file_ok <- io (checkPerms file)
212 when (dir_ok && file_ok) $ do
213 either_hdl <- io (IO.try (openFile "./.ghci" ReadMode))
216 Right hdl -> fileLoop hdl False
218 when (read_dot_files) $ do
219 -- Read in $HOME/.ghci
220 either_dir <- io (IO.try (getEnv "HOME"))
224 cwd <- io (getCurrentDirectory)
225 when (dir /= cwd) $ do
226 let file = dir ++ "/.ghci"
227 ok <- io (checkPerms file)
229 either_hdl <- io (IO.try (openFile file ReadMode))
232 Right hdl -> fileLoop hdl False
234 -- Perform a :load for files given on the GHCi command line
235 when (not (null paths)) $
236 ghciHandle showException $
239 -- if verbosity is greater than 0, or we are connected to a
240 -- terminal, display the prompt in the interactive loop.
241 is_tty <- io (hIsTerminalDevice stdin)
242 let show_prompt = verbosity dflags > 0 || is_tty
246 -- enter the interactive loop
247 interactiveLoop is_tty show_prompt
249 -- just evaluate the expression we were given
254 io $ do when (verbosity dflags > 0) $ putStrLn "Leaving GHCi."
257 interactiveLoop is_tty show_prompt = do
258 -- Ignore ^C exceptions caught here
259 ghciHandleDyn (\e -> case e of
260 Interrupted -> ghciUnblock (interactiveLoop is_tty show_prompt)
261 _other -> return ()) $ do
263 -- read commands from stdin
267 else fileLoop stdin show_prompt
269 fileLoop stdin show_prompt
273 -- NOTE: We only read .ghci files if they are owned by the current user,
274 -- and aren't world writable. Otherwise, we could be accidentally
275 -- running code planted by a malicious third party.
277 -- Furthermore, We only read ./.ghci if . is owned by the current user
278 -- and isn't writable by anyone else. I think this is sufficient: we
279 -- don't need to check .. and ../.. etc. because "." always refers to
280 -- the same directory while a process is running.
282 checkPerms :: String -> IO Bool
284 #ifdef mingw32_HOST_OS
287 DriverUtil.handle (\_ -> return False) $ do
288 st <- getFileStatus name
290 if fileOwner st /= me then do
291 putStrLn $ "WARNING: " ++ name ++ " is owned by someone else, IGNORING!"
294 let mode = fileMode st
295 if (groupWriteMode == (mode `intersectFileModes` groupWriteMode))
296 || (otherWriteMode == (mode `intersectFileModes` otherWriteMode))
298 putStrLn $ "*** WARNING: " ++ name ++
299 " is writable by someone else, IGNORING!"
304 fileLoop :: Handle -> Bool -> GHCi ()
305 fileLoop hdl prompt = do
306 cmstate <- getCmState
307 (mod,imports) <- io (cmGetContext cmstate)
308 when prompt (io (putStr (mkPrompt mod imports)))
309 l <- io (IO.try (hGetLine hdl))
311 Left e | isEOFError e -> return ()
312 | InvalidArgument <- etype -> return ()
313 | otherwise -> io (ioError e)
314 where etype = ioeGetErrorType e
315 -- treat InvalidArgument in the same way as EOF:
316 -- this can happen if the user closed stdin, or
317 -- perhaps did getContents which closes stdin at
320 case remove_spaces l of
321 "" -> fileLoop hdl prompt
322 l -> do quit <- runCommand l
323 if quit then return () else fileLoop hdl prompt
325 stringLoop :: [String] -> GHCi ()
326 stringLoop [] = return ()
327 stringLoop (s:ss) = do
328 case remove_spaces s of
330 l -> do quit <- runCommand l
331 if quit then return () else stringLoop ss
333 mkPrompt toplevs exports
334 = concat (intersperse " " (map ('*':) toplevs ++ exports)) ++ "> "
337 readlineLoop :: GHCi ()
339 cmstate <- getCmState
340 (mod,imports) <- io (cmGetContext cmstate)
342 l <- io (readline (mkPrompt mod imports)
343 `finally` setNonBlockingFD 0)
344 -- readline sometimes puts stdin into blocking mode,
345 -- so we need to put it back for the IO library
349 case remove_spaces l of
354 if quit then return () else readlineLoop
357 runCommand :: String -> GHCi Bool
358 runCommand c = ghciHandle handler (doCommand c)
360 -- This version is for the GHC command-line option -e. The only difference
361 -- from runCommand is that it catches the ExitException exception and
362 -- exits, rather than printing out the exception.
363 runCommandEval c = ghciHandle handleEval (doCommand c)
365 handleEval (ExitException code) = io (exitWith code)
366 handleEval e = do showException e
367 io (exitWith (ExitFailure 1))
369 -- This is the exception handler for exceptions generated by the
370 -- user's code; it normally just prints out the exception. The
371 -- handler must be recursive, in case showing the exception causes
372 -- more exceptions to be raised.
374 -- Bugfix: if the user closed stdout or stderr, the flushing will fail,
375 -- raising another exception. We therefore don't put the recursive
376 -- handler arond the flushing operation, so if stderr is closed
377 -- GHCi will just die gracefully rather than going into an infinite loop.
378 handler :: Exception -> GHCi Bool
379 handler exception = do
381 io installSignalHandlers
382 ghciHandle handler (showException exception >> return False)
384 showException (DynException dyn) =
385 case fromDynamic dyn of
386 Nothing -> io (putStrLn ("*** Exception: (unknown)"))
387 Just Interrupted -> io (putStrLn "Interrupted.")
388 Just (CmdLineError s) -> io (putStrLn s) -- omit the location for CmdLineError
389 Just ph@PhaseFailed{} -> io (putStrLn (showGhcException ph "")) -- ditto
390 Just other_ghc_ex -> io (print other_ghc_ex)
392 showException other_exception
393 = io (putStrLn ("*** Exception: " ++ show other_exception))
395 doCommand (':' : command) = specialCommand command
397 = do timeIt (do nms <- runStmt stmt; finishEvalExpr nms)
400 runStmt :: String -> GHCi [Name]
402 | null (filter (not.isSpace) stmt) = return []
404 = do st <- getGHCiState
405 cmstate <- getCmState
406 (new_cmstate, result) <-
407 io $ withProgName (progname st) $ withArgs (args st) $
408 cmRunStmt cmstate stmt
409 setGHCiState st{cmstate = new_cmstate}
411 CmRunFailed -> return []
412 CmRunException e -> throw e -- this is caught by runCommand(Eval)
413 CmRunOk names -> return names
415 -- possibly print the type and revert CAFs after evaluating an expression
417 = do b <- isOptionSet ShowType
418 cmstate <- getCmState
419 when b (mapM_ (showTypeOfName cmstate) names)
422 io installSignalHandlers
423 b <- isOptionSet RevertCAFs
424 io (when b revertCAFs)
427 showTypeOfName :: CmState -> Name -> GHCi ()
428 showTypeOfName cmstate n
429 = do maybe_str <- io (cmTypeOfName cmstate n)
432 Just str -> io (putStrLn (showSDoc (ppr n) ++ " :: " ++ str))
434 specialCommand :: String -> GHCi Bool
435 specialCommand ('!':str) = shellEscape (dropWhile isSpace str)
436 specialCommand str = do
437 let (cmd,rest) = break isSpace str
438 cmds <- io (readIORef commands)
439 case [ (s,f) | (s,f) <- cmds, prefixMatch cmd s ] of
440 [] -> io (hPutStr stdout ("unknown command ':" ++ cmd ++ "'\n"
441 ++ shortHelpText) >> return False)
442 [(_,f)] -> f (dropWhile isSpace rest)
443 cs -> io (hPutStrLn stdout ("prefix " ++ cmd ++
444 " matches multiple commands (" ++
445 foldr1 (\a b -> a ++ ',':b) (map fst cs)
446 ++ ")") >> return False)
448 noArgs c = throwDyn (CmdLineError ("command '" ++ c ++ "' takes no arguments"))
451 -----------------------------------------------------------------------------
452 -- To flush buffers for the *interpreted* computation we need
453 -- to refer to *its* stdout/stderr handles
455 GLOBAL_VAR(flush_interp, error "no flush_interp", IO ())
456 GLOBAL_VAR(turn_off_buffering, error "no flush_stdout", IO ())
458 no_buf_cmd = "System.IO.hSetBuffering System.IO.stdout System.IO.NoBuffering" ++
459 " Prelude.>> System.IO.hSetBuffering System.IO.stderr System.IO.NoBuffering"
460 flush_cmd = "System.IO.hFlush System.IO.stdout Prelude.>> System.IO.hFlush IO.stderr"
462 initInterpBuffering :: CmState -> IO ()
463 initInterpBuffering cmstate
464 = do maybe_hval <- cmCompileExpr cmstate no_buf_cmd
467 Just hval -> writeIORef turn_off_buffering (unsafeCoerce# hval :: IO ())
468 other -> panic "interactiveUI:setBuffering"
470 maybe_hval <- cmCompileExpr cmstate flush_cmd
472 Just hval -> writeIORef flush_interp (unsafeCoerce# hval :: IO ())
473 _ -> panic "interactiveUI:flush"
475 turnOffBuffering -- Turn it off right now
480 flushInterpBuffers :: GHCi ()
482 = io $ do Monad.join (readIORef flush_interp)
485 turnOffBuffering :: IO ()
487 = do Monad.join (readIORef turn_off_buffering)
490 -----------------------------------------------------------------------------
493 help :: String -> GHCi ()
494 help _ = io (putStr helpText)
496 info :: String -> GHCi ()
497 info "" = throwDyn (CmdLineError "syntax: ':i <thing-you-want-info-about>'")
498 info s = do { let names = words s
499 ; init_cms <- getCmState
500 ; dflags <- getDynFlags
501 ; let exts = dopt Opt_GlasgowExts dflags
502 ; mapM_ (infoThing exts init_cms) names }
504 infoThing exts cms name
505 = do { stuff <- io (cmGetInfo cms name)
506 ; io (putStrLn (showSDocForUser (cmGetPrintUnqual cms) $
507 vcat (intersperse (text "") (map (showThing exts) stuff)))) }
509 showThing :: Bool -> GetInfoResult -> SDoc
510 showThing exts (wanted_str, thing, fixity, src_loc, insts)
511 = vcat [ showWithLoc src_loc (showDecl exts want_name thing),
513 vcat (map show_inst insts)]
515 want_name occ = wanted_str == occNameUserString occ
518 | fix == defaultFixity = empty
519 | otherwise = ppr fix <+> text wanted_str
521 show_inst (inst_ty, loc)
522 = showWithLoc loc (ptext SLIT("instance") <+> ppr inst_ty)
524 showWithLoc :: SrcLoc -> SDoc -> SDoc
526 = hang doc 2 (char '\t' <> show_loc loc)
527 -- The tab tries to make them line up a bit
529 show_loc loc -- The ppr function for SrcLocs is a bit wonky
530 | isGoodSrcLoc loc = comment <+> ptext SLIT("Defined at") <+> ppr loc
531 | otherwise = comment <+> ppr loc
532 comment = ptext SLIT("--")
535 -- Now there is rather a lot of goop just to print declarations in a
536 -- civilised way with "..." for the parts we are less interested in.
538 showDecl :: Bool -> (OccName -> Bool) -> IfaceDecl -> SDoc
539 showDecl exts want_name (IfaceForeign {ifName = tc})
540 = ppr tc <+> ptext SLIT("is a foreign type")
542 showDecl exts want_name (IfaceId {ifName = var, ifType = ty})
543 = ppr var <+> dcolon <+> showType exts ty
545 showDecl exts want_name (IfaceSyn {ifName = tycon, ifTyVars = tyvars, ifSynRhs = mono_ty})
546 = hang (ptext SLIT("type") <+> pprIfaceDeclHead [] tycon tyvars)
547 2 (equals <+> ppr mono_ty)
549 showDecl exts want_name (IfaceData {ifName = tycon,
550 ifTyVars = tyvars, ifCons = condecls})
551 = hang (pp_nd <+> pprIfaceDeclHead context tycon tyvars)
552 2 (add_bars (ppr_trim show_con cs))
554 show_con (IfVanillaCon { ifConOcc = con_name, ifConInfix = is_infix, ifConArgTys = tys,
555 ifConStricts = strs, ifConFields = flds})
556 | want_name tycon || want_name con_name || any want_name flds
557 = Just (show_guts con_name is_infix tys_w_strs flds)
558 | otherwise = Nothing
560 tys_w_strs = tys `zip` (strs ++ repeat NotMarkedStrict)
561 show_con (IfGadtCon { ifConOcc = con_name, ifConTyVars = tvs, ifConCtxt = theta,
562 ifConArgTys = arg_tys, ifConResTys = res_tys, ifConStricts = strs })
563 | want_name tycon || want_name con_name
564 = Just (ppr_bndr con_name <+> colon <+> pprIfaceForAllPart tvs theta pp_tau)
565 | otherwise = Nothing
567 tys_w_strs = arg_tys `zip` (strs ++ repeat NotMarkedStrict)
568 pp_tau = foldr add pp_res_ty tys_w_strs
569 pp_res_ty = ppr_bndr tycon <+> hsep (map pprParendIfaceType res_tys)
570 add bty pp_ty = ppr_bangty bty <+> arrow <+> pp_ty
572 show_guts con True [ty1, ty2] flds = sep [ppr_bangty ty1, ppr con, ppr_bangty ty2]
573 show_guts con _ tys [] = ppr_bndr con <+> sep (map ppr_bangty tys)
574 show_guts con _ tys flds
575 = ppr_bndr con <+> braces (sep (punctuate comma (ppr_trim show_fld (tys `zip` flds))))
577 show_fld (bty, fld) | want_name tycon || want_name con || want_name fld
578 = Just (ppr_bndr fld <+> dcolon <+> ppr_bangty bty)
579 | otherwise = Nothing
581 (pp_nd, context, cs) = case condecls of
582 IfAbstractTyCon -> (ptext SLIT("data"), [], [])
583 IfDataTyCon (Just cxt) cs -> (ptext SLIT("data"), cxt, cs)
584 IfDataTyCon Nothing cs -> (ptext SLIT("data"), [], cs)
585 IfNewTyCon c -> (ptext SLIT("newtype"), [], [c])
588 add_bars [c] = equals <+> c
589 add_bars (c:cs) = equals <+> sep (c : map (char '|' <+>) cs)
591 ppr_bangty (ty, str) = ppr_str str <> pprParendIfaceType ty
592 ppr_str MarkedStrict = char '!'
593 ppr_str MarkedUnboxed = ptext SLIT("!!")
594 ppr_str NotMarkedStrict = empty
596 showDecl exts want_name (IfaceClass {ifCtxt = context, ifName = clas, ifTyVars = tyvars,
597 ifFDs = fds, ifSigs = sigs})
598 = hang (ptext SLIT("class") <+> pprIfaceDeclHead context clas tyvars
599 <+> pprFundeps fds <+> opt_where)
600 2 (vcat (ppr_trim show_op sigs))
602 opt_where | null sigs = empty
603 | otherwise = ptext SLIT("where")
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)