1 {-# OPTIONS -#include "Linker.h" #-}
2 -----------------------------------------------------------------------------
4 -- GHC Interactive User Interface
6 -- (c) The GHC Team 2005-2006
8 -----------------------------------------------------------------------------
10 module InteractiveUI ( interactiveUI, ghciWelcomeMsg ) where
12 #include "HsVersions.h"
14 import qualified GhciMonad
15 import GhciMonad hiding (runStmt)
20 import qualified GHC hiding (resume, runStmt)
21 import GHC ( Session, LoadHowMuch(..), Target(..), TargetId(..),
22 Module, ModuleName, TyThing(..), Phase,
23 BreakIndex, SrcSpan, Resume, SingleStep )
33 import HscTypes ( implicitTyThings )
34 import qualified RdrName ( getGRE_NameQualifier_maybes ) -- should this come via GHC?
35 import Outputable hiding (printForUser, printForUserPartWay)
36 import Module -- for ModuleEnv
40 -- Other random utilities
43 import BasicTypes hiding (isTopLevel)
44 import Panic hiding (showException)
50 import Maybes ( orElse )
54 #ifndef mingw32_HOST_OS
55 import System.Posix hiding (getEnv)
57 import GHC.ConsoleHandler ( flushConsole )
58 import qualified System.Win32
62 import Control.Concurrent ( yield ) -- Used in readline loop
63 import System.Console.Editline.Readline as Readline
68 import Control.Exception as Exception
69 -- import Control.Concurrent
71 import System.FilePath
72 import qualified Data.ByteString.Char8 as BS
76 import System.Environment
77 import System.Exit ( exitWith, ExitCode(..) )
78 import System.Directory
80 import System.IO.Error as IO
84 import Control.Monad as Monad
88 import GHC.Exts ( unsafeCoerce# )
89 import GHC.IOBase ( IOErrorType(InvalidArgument) )
92 import Data.IORef ( IORef, readIORef, writeIORef )
95 import System.Posix.Internals ( setNonBlockingFD )
98 -----------------------------------------------------------------------------
100 ghciWelcomeMsg :: String
101 ghciWelcomeMsg = "GHCi, version " ++ cProjectVersion ++
102 ": http://www.haskell.org/ghc/ :? for help"
104 cmdName :: Command -> String
105 cmdName (n,_,_,_) = n
107 GLOBAL_VAR(macros_ref, [], [Command])
109 builtin_commands :: [Command]
111 -- Hugs users are accustomed to :e, so make sure it doesn't overlap
112 ("?", keepGoing help, Nothing, completeNone),
113 ("add", keepGoingPaths addModule, Just filenameWordBreakChars, completeFilename),
114 ("abandon", keepGoing abandonCmd, Nothing, completeNone),
115 ("break", keepGoing breakCmd, Nothing, completeIdentifier),
116 ("back", keepGoing backCmd, Nothing, completeNone),
117 ("browse", keepGoing (browseCmd False), Nothing, completeModule),
118 ("browse!", keepGoing (browseCmd True), Nothing, completeModule),
119 ("cd", keepGoing changeDirectory, Just filenameWordBreakChars, completeFilename),
120 ("check", keepGoing checkModule, Nothing, completeHomeModule),
121 ("continue", keepGoing continueCmd, Nothing, completeNone),
122 ("cmd", keepGoing cmdCmd, Nothing, completeIdentifier),
123 ("ctags", keepGoing createCTagsFileCmd, Just filenameWordBreakChars, completeFilename),
124 ("def", keepGoing (defineMacro False), Nothing, completeIdentifier),
125 ("def!", keepGoing (defineMacro True), Nothing, completeIdentifier),
126 ("delete", keepGoing deleteCmd, Nothing, completeNone),
127 ("e", keepGoing editFile, Just filenameWordBreakChars, completeFilename),
128 ("edit", keepGoing editFile, Just filenameWordBreakChars, completeFilename),
129 ("etags", keepGoing createETagsFileCmd, Just filenameWordBreakChars, completeFilename),
130 ("force", keepGoing forceCmd, Nothing, completeIdentifier),
131 ("forward", keepGoing forwardCmd, Nothing, completeNone),
132 ("help", keepGoing help, Nothing, completeNone),
133 ("history", keepGoing historyCmd, Nothing, completeNone),
134 ("info", keepGoing info, Nothing, completeIdentifier),
135 ("kind", keepGoing kindOfType, Nothing, completeIdentifier),
136 ("load", keepGoingPaths loadModule_, Just filenameWordBreakChars, completeHomeModuleOrFile),
137 ("list", keepGoing listCmd, Nothing, completeNone),
138 ("module", keepGoing setContext, Nothing, completeModule),
139 ("main", keepGoing runMain, Nothing, completeIdentifier),
140 ("print", keepGoing printCmd, Nothing, completeIdentifier),
141 ("quit", quit, Nothing, completeNone),
142 ("reload", keepGoing reloadModule, Nothing, completeNone),
143 ("run", keepGoing runRun, Nothing, completeIdentifier),
144 ("set", keepGoing setCmd, Just flagWordBreakChars, completeSetOptions),
145 ("show", keepGoing showCmd, Nothing, completeNone),
146 ("sprint", keepGoing sprintCmd, Nothing, completeIdentifier),
147 ("step", keepGoing stepCmd, Nothing, completeIdentifier),
148 ("steplocal", keepGoing stepLocalCmd, Nothing, completeIdentifier),
149 ("stepmodule",keepGoing stepModuleCmd, Nothing, completeIdentifier),
150 ("type", keepGoing typeOfExpr, Nothing, completeIdentifier),
151 ("trace", keepGoing traceCmd, Nothing, completeIdentifier),
152 ("undef", keepGoing undefineMacro, Nothing, completeMacro),
153 ("unset", keepGoing unsetOptions, Just flagWordBreakChars, completeSetOptions)
157 -- We initialize readline (in the interactiveUI function) to use
158 -- word_break_chars as the default set of completion word break characters.
159 -- This can be overridden for a particular command (for example, filename
160 -- expansion shouldn't consider '/' to be a word break) by setting the third
161 -- entry in the Command tuple above.
163 -- NOTE: in order for us to override the default correctly, any custom entry
164 -- must be a SUBSET of word_break_chars.
166 word_break_chars :: String
167 word_break_chars = let symbols = "!#$%&*+/<=>?@\\^|-~"
168 specials = "(),;[]`{}"
170 in spaces ++ specials ++ symbols
173 flagWordBreakChars, filenameWordBreakChars :: String
174 flagWordBreakChars = " \t\n"
175 filenameWordBreakChars = " \t\n\\`@$><=;|&{(" -- bash defaults
178 keepGoing :: (String -> GHCi ()) -> (String -> GHCi Bool)
179 keepGoing a str = a str >> return False
181 keepGoingPaths :: ([FilePath] -> GHCi ()) -> (String -> GHCi Bool)
183 = do case toArgs str of
184 Left err -> io (hPutStrLn stderr err)
188 shortHelpText :: String
189 shortHelpText = "use :? for help.\n"
193 " Commands available from the prompt:\n" ++
195 " <statement> evaluate/run <statement>\n" ++
196 " : repeat last command\n" ++
197 " :{\\n ..lines.. \\n:}\\n multiline command\n" ++
198 " :add <filename> ... add module(s) to the current target set\n" ++
199 " :browse[!] [[*]<mod>] display the names defined by module <mod>\n" ++
200 " (!: more details; *: all top-level names)\n" ++
201 " :cd <dir> change directory to <dir>\n" ++
202 " :cmd <expr> run the commands returned by <expr>::IO String\n" ++
203 " :ctags [<file>] create tags file for Vi (default: \"tags\")\n" ++
204 " :def <cmd> <expr> define a command :<cmd>\n" ++
205 " :edit <file> edit file\n" ++
206 " :edit edit last module\n" ++
207 " :etags [<file>] create tags file for Emacs (default: \"TAGS\")\n" ++
208 " :help, :? display this list of commands\n" ++
209 " :info [<name> ...] display information about the given names\n" ++
210 " :kind <type> show the kind of <type>\n" ++
211 " :load <filename> ... load module(s) and their dependents\n" ++
212 " :main [<arguments> ...] run the main function with the given arguments\n" ++
213 " :module [+/-] [*]<mod> ... set the context for expression evaluation\n" ++
214 " :quit exit GHCi\n" ++
215 " :reload reload the current module set\n" ++
216 " :run function [<arguments> ...] run the function with the given arguments\n" ++
217 " :type <expr> show the type of <expr>\n" ++
218 " :undef <cmd> undefine user-defined command :<cmd>\n" ++
219 " :!<command> run the shell command <command>\n" ++
221 " -- Commands for debugging:\n" ++
223 " :abandon at a breakpoint, abandon current computation\n" ++
224 " :back go back in the history (after :trace)\n" ++
225 " :break [<mod>] <l> [<col>] set a breakpoint at the specified location\n" ++
226 " :break <name> set a breakpoint on the specified function\n" ++
227 " :continue resume after a breakpoint\n" ++
228 " :delete <number> delete the specified breakpoint\n" ++
229 " :delete * delete all breakpoints\n" ++
230 " :force <expr> print <expr>, forcing unevaluated parts\n" ++
231 " :forward go forward in the history (after :back)\n" ++
232 " :history [<n>] after :trace, show the execution history\n" ++
233 " :list show the source code around current breakpoint\n" ++
234 " :list identifier show the source code for <identifier>\n" ++
235 " :list [<module>] <line> show the source code around line number <line>\n" ++
236 " :print [<name> ...] prints a value without forcing its computation\n" ++
237 " :sprint [<name> ...] simplifed version of :print\n" ++
238 " :step single-step after stopping at a breakpoint\n"++
239 " :step <expr> single-step into <expr>\n"++
240 " :steplocal single-step within the current top-level binding\n"++
241 " :stepmodule single-step restricted to the current module\n"++
242 " :trace trace after stopping at a breakpoint\n"++
243 " :trace <expr> evaluate <expr> with tracing on (see :history)\n"++
246 " -- Commands for changing settings:\n" ++
248 " :set <option> ... set options\n" ++
249 " :set args <arg> ... set the arguments returned by System.getArgs\n" ++
250 " :set prog <progname> set the value returned by System.getProgName\n" ++
251 " :set prompt <prompt> set the prompt used in GHCi\n" ++
252 " :set editor <cmd> set the command used for :edit\n" ++
253 " :set stop <cmd> set the command to run when a breakpoint is hit\n" ++
254 " :unset <option> ... unset options\n" ++
256 " Options for ':set' and ':unset':\n" ++
258 " +r revert top-level expressions after each evaluation\n" ++
259 " +s print timing/memory stats after each evaluation\n" ++
260 " +t print type after evaluation\n" ++
261 " -<flags> most GHC command line flags can also be set here\n" ++
262 " (eg. -v2, -fglasgow-exts, etc.)\n" ++
263 " for GHCi-specific flags, see User's Guide,\n"++
264 " Flag reference, Interactive-mode options\n" ++
266 " -- Commands for displaying information:\n" ++
268 " :show bindings show the current bindings made at the prompt\n" ++
269 " :show breaks show the active breakpoints\n" ++
270 " :show context show the breakpoint context\n" ++
271 " :show modules show the currently loaded modules\n" ++
272 " :show packages show the currently active package flags\n" ++
273 " :show languages show the currently active language flags\n" ++
274 " :show <setting> show value of <setting>, which is one of\n" ++
275 " [args, prog, prompt, editor, stop]\n" ++
278 findEditor :: IO String
283 win <- System.Win32.getWindowsDirectory
284 return (win </> "notepad.exe")
289 interactiveUI :: Session -> [(FilePath, Maybe Phase)] -> Maybe [String]
291 interactiveUI session srcs maybe_exprs = do
292 -- HACK! If we happen to get into an infinite loop (eg the user
293 -- types 'let x=x in x' at the prompt), then the thread will block
294 -- on a blackhole, and become unreachable during GC. The GC will
295 -- detect that it is unreachable and send it the NonTermination
296 -- exception. However, since the thread is unreachable, everything
297 -- it refers to might be finalized, including the standard Handles.
298 -- This sounds like a bug, but we don't have a good solution right
304 -- Initialise buffering for the *interpreted* I/O system
305 initInterpBuffering session
307 when (isNothing maybe_exprs) $ do
308 -- Only for GHCi (not runghc and ghc -e):
310 -- Turn buffering off for the compiled program's stdout/stderr
312 -- Turn buffering off for GHCi's stdout
314 hSetBuffering stdout NoBuffering
315 -- We don't want the cmd line to buffer any input that might be
316 -- intended for the program, so unbuffer stdin.
317 hSetBuffering stdin NoBuffering
320 is_tty <- hIsTerminalDevice stdin
325 (\dir -> Readline.readHistory (dir </> "ghci_history"))
328 Readline.setAttemptedCompletionFunction (Just completeWord)
329 --Readline.parseAndBind "set show-all-if-ambiguous 1"
331 Readline.setBasicWordBreakCharacters word_break_chars
332 Readline.setCompleterWordBreakCharacters word_break_chars
333 Readline.setCompletionAppendCharacter Nothing
336 -- initial context is just the Prelude
337 prel_mod <- GHC.findModule session (GHC.mkModuleName "Prelude")
339 GHC.setContext session [] [prel_mod]
341 default_editor <- findEditor
343 cwd <- getCurrentDirectory
345 startGHCi (runGHCi srcs maybe_exprs)
346 GHCiState{ progname = "<interactive>",
350 editor = default_editor,
356 tickarrays = emptyModuleEnv,
357 last_command = Nothing,
361 ghc_e = isJust maybe_exprs
365 Readline.stifleHistory 100
366 withGhcAppData (\dir -> Readline.writeHistory (dir </> "ghci_history"))
368 Readline.resetTerminal Nothing
373 withGhcAppData :: (FilePath -> IO a) -> IO a -> IO a
374 withGhcAppData right left = do
375 either_dir <- IO.try (getAppUserDataDirectory "ghc")
377 Right dir -> right dir
381 runGHCi :: [(FilePath, Maybe Phase)] -> Maybe [String] -> GHCi ()
382 runGHCi paths maybe_exprs = do
384 read_dot_files = not opt_IgnoreDotGhci
386 current_dir = return (Just ".ghci")
388 app_user_dir = io $ withGhcAppData
389 (\dir -> return (Just (dir </> "ghci.conf")))
393 either_dir <- io $ IO.try (getEnv "HOME")
395 Right home -> return (Just (home </> ".ghci"))
398 sourceConfigFile :: FilePath -> GHCi ()
399 sourceConfigFile file = do
400 exists <- io $ doesFileExist file
402 dir_ok <- io $ checkPerms (getDirectory file)
403 file_ok <- io $ checkPerms file
404 when (dir_ok && file_ok) $ do
405 either_hdl <- io $ IO.try (openFile file ReadMode)
408 Right hdl -> runCommands (fileLoop hdl False False)
410 getDirectory f = case takeDirectory f of "" -> "."; d -> d
412 when (read_dot_files) $ do
413 cfgs0 <- sequence [ current_dir, app_user_dir, home_dir ]
414 cfgs <- io $ mapM canonicalizePath (catMaybes cfgs0)
415 mapM_ sourceConfigFile (nub cfgs)
416 -- nub, because we don't want to read .ghci twice if the
419 -- Perform a :load for files given on the GHCi command line
420 -- When in -e mode, if the load fails then we want to stop
421 -- immediately rather than going on to evaluate the expression.
422 when (not (null paths)) $ do
423 ok <- ghciHandle (\e -> do showException e; return Failed) $
425 when (isJust maybe_exprs && failed ok) $
426 io (exitWith (ExitFailure 1))
428 -- if verbosity is greater than 0, or we are connected to a
429 -- terminal, display the prompt in the interactive loop.
430 is_tty <- io (hIsTerminalDevice stdin)
431 dflags <- getDynFlags
432 let show_prompt = verbosity dflags > 0 || is_tty
437 #if defined(mingw32_HOST_OS)
438 -- The win32 Console API mutates the first character of
439 -- type-ahead when reading from it in a non-buffered manner. Work
440 -- around this by flushing the input buffer of type-ahead characters,
441 -- but only if stdin is available.
442 flushed <- io (IO.try (GHC.ConsoleHandler.flushConsole stdin))
444 Left err | isDoesNotExistError err -> return ()
445 | otherwise -> io (ioError err)
446 Right () -> return ()
448 -- enter the interactive loop
449 interactiveLoop is_tty show_prompt
451 -- just evaluate the expression we were given
452 enqueueCommands exprs
453 let handle e = do st <- getGHCiState
454 -- Jump through some hoops to get the
455 -- current progname in the exception text:
456 -- <progname>: <exception>
457 io $ withProgName (progname st)
458 -- this used to be topHandlerFastExit, see #2228
460 runCommands' handle (return Nothing)
463 io $ do when (verbosity dflags > 0) $ putStrLn "Leaving GHCi."
465 interactiveLoop :: Bool -> Bool -> GHCi ()
466 interactiveLoop is_tty show_prompt =
467 -- Ignore ^C exceptions caught here
468 ghciHandleDyn (\e -> case e of
470 #if defined(mingw32_HOST_OS)
473 interactiveLoop is_tty show_prompt
474 _other -> return ()) $
476 ghciUnblock $ do -- unblock necessary if we recursed from the
477 -- exception handler above.
479 -- read commands from stdin
482 then runCommands readlineLoop
483 else runCommands (fileLoop stdin show_prompt is_tty)
485 runCommands (fileLoop stdin show_prompt is_tty)
489 -- NOTE: We only read .ghci files if they are owned by the current user,
490 -- and aren't world writable. Otherwise, we could be accidentally
491 -- running code planted by a malicious third party.
493 -- Furthermore, We only read ./.ghci if . is owned by the current user
494 -- and isn't writable by anyone else. I think this is sufficient: we
495 -- don't need to check .. and ../.. etc. because "." always refers to
496 -- the same directory while a process is running.
498 checkPerms :: String -> IO Bool
499 #ifdef mingw32_HOST_OS
504 Util.handle (\_ -> return False) $ do
505 st <- getFileStatus name
507 if fileOwner st /= me then do
508 putStrLn $ "WARNING: " ++ name ++ " is owned by someone else, IGNORING!"
511 let mode = fileMode st
512 if (groupWriteMode == (mode `intersectFileModes` groupWriteMode))
513 || (otherWriteMode == (mode `intersectFileModes` otherWriteMode))
515 putStrLn $ "*** WARNING: " ++ name ++
516 " is writable by someone else, IGNORING!"
521 fileLoop :: Handle -> Bool -> Bool -> GHCi (Maybe String)
522 fileLoop hdl show_prompt is_tty = do
523 when show_prompt $ do
526 l <- io (IO.try (hGetLine hdl))
528 Left e | isEOFError e -> return Nothing
529 | InvalidArgument <- etype -> return Nothing
530 | otherwise -> io (ioError e)
531 where etype = ioeGetErrorType e
532 -- treat InvalidArgument in the same way as EOF:
533 -- this can happen if the user closed stdin, or
534 -- perhaps did getContents which closes stdin at
537 str <- io $ consoleInputToUnicode is_tty l
540 #ifdef mingw32_HOST_OS
541 -- Convert the console input into Unicode according to the current code page.
542 -- The Windows console stores Unicode characters directly, so this is a
543 -- rather roundabout way of doing things... oh well.
544 -- See #782, #1483, #1649
545 consoleInputToUnicode :: Bool -> String -> IO String
546 consoleInputToUnicode is_tty str
548 cp <- System.Win32.getConsoleCP
549 System.Win32.stringToUnicode cp str
551 decodeStringAsUTF8 str
553 -- for Unix, assume the input is in UTF-8 and decode it to a Unicode String.
555 consoleInputToUnicode :: Bool -> String -> IO String
556 consoleInputToUnicode _is_tty str = decodeStringAsUTF8 str
559 decodeStringAsUTF8 :: String -> IO String
560 decodeStringAsUTF8 str =
561 withCStringLen str $ \(cstr,len) ->
562 utf8DecodeString (castPtr cstr :: Ptr Word8) len
564 mkPrompt :: GHCi String
566 session <- getSession
567 (toplevs,exports) <- io (GHC.getContext session)
568 resumes <- io $ GHC.getResumeContext session
569 -- st <- getGHCiState
575 let ix = GHC.resumeHistoryIx r
577 then return (brackets (ppr (GHC.resumeSpan r)) <> space)
579 let hist = GHC.resumeHistory r !! (ix-1)
580 span <- io$ GHC.getHistorySpan session hist
581 return (brackets (ppr (negate ix) <> char ':'
582 <+> ppr span) <> space)
584 dots | _:rs <- resumes, not (null rs) = text "... "
591 -- let (btoplevs, bexports) = fromMaybe ([],[]) (remembered_ctx st) in
592 -- hsep (map (\m -> text "!*" <> ppr (GHC.moduleName m)) btoplevs) <+>
593 -- hsep (map (\m -> char '!' <> ppr (GHC.moduleName m)) bexports) <+>
594 hsep (map (\m -> char '*' <> ppr (GHC.moduleName m)) toplevs) <+>
595 hsep (map (ppr . GHC.moduleName) exports)
597 deflt_prompt = dots <> context_bit <> modules_bit
599 f ('%':'s':xs) = deflt_prompt <> f xs
600 f ('%':'%':xs) = char '%' <> f xs
601 f (x:xs) = char x <> f xs
605 return (showSDoc (f (prompt st)))
609 readlineLoop :: GHCi (Maybe String)
612 saveSession -- for use by completion
614 l <- io (readline prompt `finally` setNonBlockingFD 0)
615 -- readline sometimes puts stdin into blocking mode,
616 -- so we need to put it back for the IO library
619 Nothing -> return Nothing
620 Just "" -> return (Just "") -- Don't put empty lines in the history
623 str <- io $ consoleInputToUnicode True l
627 queryQueue :: GHCi (Maybe String)
632 c:cs -> do setGHCiState st{ cmdqueue = cs }
635 runCommands :: GHCi (Maybe String) -> GHCi ()
636 runCommands = runCommands' handler
638 runCommands' :: (Exception -> GHCi Bool) -- Exception handler
639 -> GHCi (Maybe String) -> GHCi ()
640 runCommands' eh getCmd = do
641 mb_cmd <- noSpace queryQueue
642 mb_cmd <- maybe (noSpace getCmd) (return . Just) mb_cmd
646 b <- ghciHandle eh (doCommand c)
647 if b then return () else runCommands' eh getCmd
649 noSpace q = q >>= maybe (return Nothing)
650 (\c->case removeSpaces c of
652 ":{" -> multiLineCmd q
653 c -> return (Just c) )
657 setGHCiState st{ prompt = "%s| " }
658 mb_cmd <- collectCommand q ""
659 getGHCiState >>= \st->setGHCiState st{ prompt = p }
661 -- we can't use removeSpaces for the sublines here, so
662 -- multiline commands are somewhat more brittle against
663 -- fileformat errors (such as \r in dos input on unix),
664 -- we get rid of any extra spaces for the ":}" test;
665 -- we also avoid silent failure if ":}" is not found;
666 -- and since there is no (?) valid occurrence of \r (as
667 -- opposed to its String representation, "\r") inside a
668 -- ghci command, we replace any such with ' ' (argh:-(
669 collectCommand q c = q >>=
670 maybe (io (ioError collectError))
671 (\l->if removeSpaces l == ":}"
672 then return (Just $ removeSpaces c)
673 else collectCommand q (c++map normSpace l))
674 where normSpace '\r' = ' '
676 -- QUESTION: is userError the one to use here?
677 collectError = userError "unterminated multiline command :{ .. :}"
678 doCommand (':' : cmd) = specialCommand cmd
679 doCommand stmt = do timeIt $ runStmt stmt GHC.RunToCompletion
682 enqueueCommands :: [String] -> GHCi ()
683 enqueueCommands cmds = do
685 setGHCiState st{ cmdqueue = cmds ++ cmdqueue st }
688 runStmt :: String -> SingleStep -> GHCi Bool
690 | null (filter (not.isSpace) stmt) = return False
691 | ["import", mod] <- words stmt = keepGoing setContext ('+':mod)
693 = do result <- GhciMonad.runStmt stmt step
694 afterRunStmt (const True) result
696 --afterRunStmt :: GHC.RunResult -> GHCi Bool
697 -- False <=> the statement failed to compile
698 afterRunStmt :: (SrcSpan -> Bool) -> GHC.RunResult -> GHCi Bool
699 afterRunStmt _ (GHC.RunException e) = throw e
700 afterRunStmt step_here run_result = do
701 session <- getSession
702 resumes <- io $ GHC.getResumeContext session
704 GHC.RunOk names -> do
705 show_types <- isOptionSet ShowType
706 when show_types $ printTypeOfNames session names
707 GHC.RunBreak _ names mb_info
708 | isNothing mb_info ||
709 step_here (GHC.resumeSpan $ head resumes) -> do
710 printForUser $ ptext (sLit "Stopped at") <+>
711 ppr (GHC.resumeSpan $ head resumes)
712 -- printTypeOfNames session names
713 let namesSorted = sortBy compareNames names
714 tythings <- catMaybes `liftM`
715 io (mapM (GHC.lookupName session) namesSorted)
716 docs <- io$ pprTypeAndContents session [id | AnId id <- tythings]
717 printForUserPartWay docs
718 maybe (return ()) runBreakCmd mb_info
719 -- run the command set with ":set stop <cmd>"
721 enqueueCommands [stop st]
723 | otherwise -> resume GHC.SingleStep >>=
724 afterRunStmt step_here >> return ()
728 io installSignalHandlers
729 b <- isOptionSet RevertCAFs
732 return (case run_result of GHC.RunOk _ -> True; _ -> False)
734 runBreakCmd :: GHC.BreakInfo -> GHCi ()
735 runBreakCmd info = do
736 let mod = GHC.breakInfo_module info
737 nm = GHC.breakInfo_number info
739 case [ loc | (_,loc) <- breaks st,
740 breakModule loc == mod, breakTick loc == nm ] of
742 loc:_ | null cmd -> return ()
743 | otherwise -> do enqueueCommands [cmd]; return ()
744 where cmd = onBreakCmd loc
746 printTypeOfNames :: Session -> [Name] -> GHCi ()
747 printTypeOfNames session names
748 = mapM_ (printTypeOfName session) $ sortBy compareNames names
750 compareNames :: Name -> Name -> Ordering
751 n1 `compareNames` n2 = compareWith n1 `compare` compareWith n2
752 where compareWith n = (getOccString n, getSrcSpan n)
754 printTypeOfName :: Session -> Name -> GHCi ()
755 printTypeOfName session n
756 = do maybe_tything <- io (GHC.lookupName session n)
757 case maybe_tything of
759 Just thing -> printTyThing thing
762 data MaybeCommand = GotCommand Command | BadCommand | NoLastCommand
764 specialCommand :: String -> GHCi Bool
765 specialCommand ('!':str) = shellEscape (dropWhile isSpace str)
766 specialCommand str = do
767 let (cmd,rest) = break isSpace str
768 maybe_cmd <- lookupCommand cmd
770 GotCommand (_,f,_,_) -> f (dropWhile isSpace rest)
772 do io $ hPutStr stdout ("unknown command ':" ++ cmd ++ "'\n"
776 do io $ hPutStr stdout ("there is no last command to perform\n"
780 lookupCommand :: String -> GHCi (MaybeCommand)
781 lookupCommand "" = do
783 case last_command st of
784 Just c -> return $ GotCommand c
785 Nothing -> return NoLastCommand
786 lookupCommand str = do
787 mc <- io $ lookupCommand' str
789 setGHCiState st{ last_command = mc }
791 Just c -> GotCommand c
792 Nothing -> BadCommand
794 lookupCommand' :: String -> IO (Maybe Command)
795 lookupCommand' str = do
796 macros <- readIORef macros_ref
797 let cmds = builtin_commands ++ macros
798 -- look for exact match first, then the first prefix match
799 return $ case [ c | c <- cmds, str == cmdName c ] of
801 [] -> case [ c | c@(s,_,_,_) <- cmds, str `isPrefixOf` s ] of
805 getCurrentBreakSpan :: GHCi (Maybe SrcSpan)
806 getCurrentBreakSpan = do
807 session <- getSession
808 resumes <- io $ GHC.getResumeContext session
812 let ix = GHC.resumeHistoryIx r
814 then return (Just (GHC.resumeSpan r))
816 let hist = GHC.resumeHistory r !! (ix-1)
817 span <- io $ GHC.getHistorySpan session hist
820 getCurrentBreakModule :: GHCi (Maybe Module)
821 getCurrentBreakModule = do
822 session <- getSession
823 resumes <- io $ GHC.getResumeContext session
827 let ix = GHC.resumeHistoryIx r
829 then return (GHC.breakInfo_module `liftM` GHC.resumeBreakInfo r)
831 let hist = GHC.resumeHistory r !! (ix-1)
832 return $ Just $ GHC.getHistoryModule hist
834 -----------------------------------------------------------------------------
837 noArgs :: GHCi () -> String -> GHCi ()
839 noArgs _ _ = io $ putStrLn "This command takes no arguments"
841 help :: String -> GHCi ()
842 help _ = io (putStr helpText)
844 info :: String -> GHCi ()
845 info "" = throwDyn (CmdLineError "syntax: ':i <thing-you-want-info-about>'")
846 info s = do { let names = words s
847 ; session <- getSession
848 ; dflags <- getDynFlags
849 ; let pefas = dopt Opt_PrintExplicitForalls dflags
850 ; mapM_ (infoThing pefas session) names }
852 infoThing pefas session str = io $ do
853 names <- GHC.parseName session str
854 mb_stuffs <- mapM (GHC.getInfo session) names
855 let filtered = filterOutChildren (\(t,_f,_i) -> t) (catMaybes mb_stuffs)
856 unqual <- GHC.getPrintUnqual session
857 putStrLn (showSDocForUser unqual $
858 vcat (intersperse (text "") $
859 map (pprInfo pefas) filtered))
861 -- Filter out names whose parent is also there Good
862 -- example is '[]', which is both a type and data
863 -- constructor in the same type
864 filterOutChildren :: (a -> TyThing) -> [a] -> [a]
865 filterOutChildren get_thing xs
866 = [x | x <- xs, not (getName (get_thing x) `elemNameSet` implicits)]
868 implicits = mkNameSet [getName t | x <- xs, t <- implicitTyThings (get_thing x)]
870 pprInfo :: PrintExplicitForalls -> (TyThing, Fixity, [GHC.Instance]) -> SDoc
871 pprInfo pefas (thing, fixity, insts)
872 = pprTyThingInContextLoc pefas thing
873 $$ show_fixity fixity
874 $$ vcat (map GHC.pprInstance insts)
877 | fix == GHC.defaultFixity = empty
878 | otherwise = ppr fix <+> ppr (GHC.getName thing)
880 runMain :: String -> GHCi ()
881 runMain s = case toArgs s of
882 Left err -> io (hPutStrLn stderr err)
884 do dflags <- getDynFlags
885 case mainFunIs dflags of
886 Nothing -> doWithArgs args "main"
887 Just f -> doWithArgs args f
889 runRun :: String -> GHCi ()
890 runRun s = case toCmdArgs s of
891 Left err -> io (hPutStrLn stderr err)
892 Right (cmd, args) -> doWithArgs args cmd
894 doWithArgs :: [String] -> String -> GHCi ()
895 doWithArgs args cmd = enqueueCommands ["System.Environment.withArgs " ++
896 show args ++ " (" ++ cmd ++ ")"]
898 addModule :: [FilePath] -> GHCi ()
900 revertCAFs -- always revert CAFs on load/add.
901 files <- mapM expandPath files
902 targets <- mapM (\m -> io (GHC.guessTarget m Nothing)) files
903 session <- getSession
904 io (mapM_ (GHC.addTarget session) targets)
905 prev_context <- io $ GHC.getContext session
906 ok <- io (GHC.load session LoadAllTargets)
907 afterLoad ok session False prev_context
909 changeDirectory :: String -> GHCi ()
910 changeDirectory "" = do
911 -- :cd on its own changes to the user's home directory
912 either_dir <- io (IO.try getHomeDirectory)
915 Right dir -> changeDirectory dir
916 changeDirectory dir = do
917 session <- getSession
918 graph <- io (GHC.getModuleGraph session)
919 when (not (null graph)) $
920 io $ putStr "Warning: changing directory causes all loaded modules to be unloaded,\nbecause the search path has changed.\n"
921 prev_context <- io $ GHC.getContext session
922 io (GHC.setTargets session [])
923 io (GHC.load session LoadAllTargets)
924 setContextAfterLoad session prev_context False []
925 io (GHC.workingDirectoryChanged session)
926 dir <- expandPath dir
927 io (setCurrentDirectory dir)
929 editFile :: String -> GHCi ()
931 do file <- if null str then chooseEditFile else return str
935 $ throwDyn (CmdLineError "editor not set, use :set editor")
936 io $ system (cmd ++ ' ':file)
939 -- The user didn't specify a file so we pick one for them.
940 -- Our strategy is to pick the first module that failed to load,
941 -- or otherwise the first target.
943 -- XXX: Can we figure out what happened if the depndecy analysis fails
944 -- (e.g., because the porgrammeer mistyped the name of a module)?
945 -- XXX: Can we figure out the location of an error to pass to the editor?
946 -- XXX: if we could figure out the list of errors that occured during the
947 -- last load/reaload, then we could start the editor focused on the first
949 chooseEditFile :: GHCi String
951 do session <- getSession
952 let hasFailed x = io $ fmap not $ GHC.isLoaded session $ GHC.ms_mod_name x
954 graph <- io (GHC.getModuleGraph session)
955 failed_graph <- filterM hasFailed graph
956 let order g = flattenSCCs $ GHC.topSortModuleGraph True g Nothing
958 x : _ -> GHC.ml_hs_file (GHC.ms_location x)
961 case pick (order failed_graph) of
962 Just file -> return file
964 do targets <- io (GHC.getTargets session)
965 case msum (map fromTarget targets) of
966 Just file -> return file
967 Nothing -> throwDyn (CmdLineError "No files to edit.")
969 where fromTarget (GHC.Target (GHC.TargetFile f _) _) = Just f
970 fromTarget _ = Nothing -- when would we get a module target?
972 defineMacro :: Bool{-overwrite-} -> String -> GHCi ()
973 defineMacro overwrite s = do
974 let (macro_name, definition) = break isSpace s
975 macros <- io (readIORef macros_ref)
976 let defined = map cmdName macros
979 then io $ putStrLn "no macros defined"
980 else io $ putStr ("the following macros are defined:\n" ++
983 if (not overwrite && macro_name `elem` defined)
984 then throwDyn (CmdLineError
985 ("macro '" ++ macro_name ++ "' is already defined"))
988 let filtered = [ cmd | cmd <- macros, cmdName cmd /= macro_name ]
990 -- give the expression a type signature, so we can be sure we're getting
991 -- something of the right type.
992 let new_expr = '(' : definition ++ ") :: String -> IO String"
994 -- compile the expression
996 maybe_hv <- io (GHC.compileExpr cms new_expr)
999 Just hv -> io (writeIORef macros_ref --
1000 (filtered ++ [(macro_name, runMacro hv, Nothing, completeNone)]))
1002 runMacro :: GHC.HValue{-String -> IO String-} -> String -> GHCi Bool
1004 str <- io ((unsafeCoerce# fun :: String -> IO String) s)
1005 enqueueCommands (lines str)
1008 undefineMacro :: String -> GHCi ()
1009 undefineMacro str = mapM_ undef (words str)
1010 where undef macro_name = do
1011 cmds <- io (readIORef macros_ref)
1012 if (macro_name `notElem` map cmdName cmds)
1013 then throwDyn (CmdLineError
1014 ("macro '" ++ macro_name ++ "' is not defined"))
1016 io (writeIORef macros_ref (filter ((/= macro_name) . cmdName) cmds))
1018 cmdCmd :: String -> GHCi ()
1020 let expr = '(' : str ++ ") :: IO String"
1021 session <- getSession
1022 maybe_hv <- io (GHC.compileExpr session expr)
1024 Nothing -> return ()
1026 cmds <- io $ (unsafeCoerce# hv :: IO String)
1027 enqueueCommands (lines cmds)
1030 loadModule :: [(FilePath, Maybe Phase)] -> GHCi SuccessFlag
1031 loadModule fs = timeIt (loadModule' fs)
1033 loadModule_ :: [FilePath] -> GHCi ()
1034 loadModule_ fs = do loadModule (zip fs (repeat Nothing)); return ()
1036 loadModule' :: [(FilePath, Maybe Phase)] -> GHCi SuccessFlag
1037 loadModule' files = do
1038 session <- getSession
1039 prev_context <- io $ GHC.getContext session
1042 discardActiveBreakPoints
1043 io (GHC.setTargets session [])
1044 io (GHC.load session LoadAllTargets)
1047 let (filenames, phases) = unzip files
1048 exp_filenames <- mapM expandPath filenames
1049 let files' = zip exp_filenames phases
1050 targets <- io (mapM (uncurry GHC.guessTarget) files')
1052 -- NOTE: we used to do the dependency anal first, so that if it
1053 -- fails we didn't throw away the current set of modules. This would
1054 -- require some re-working of the GHC interface, so we'll leave it
1055 -- as a ToDo for now.
1057 io (GHC.setTargets session targets)
1058 doLoad session False prev_context LoadAllTargets
1060 checkModule :: String -> GHCi ()
1062 let modl = GHC.mkModuleName m
1063 session <- getSession
1064 prev_context <- io $ GHC.getContext session
1065 result <- io (GHC.checkModule session modl False)
1067 Nothing -> io $ putStrLn "Nothing"
1068 Just r -> io $ putStrLn (showSDoc (
1069 case GHC.checkedModuleInfo r of
1070 Just cm | Just scope <- GHC.modInfoTopLevelScope cm ->
1072 (local,global) = partition ((== modl) . GHC.moduleName . GHC.nameModule) scope
1074 (text "global names: " <+> ppr global) $$
1075 (text "local names: " <+> ppr local)
1077 afterLoad (successIf (isJust result)) session False prev_context
1079 reloadModule :: String -> GHCi ()
1081 session <- getSession
1082 prev_context <- io $ GHC.getContext session
1083 doLoad session True prev_context $
1084 if null m then LoadAllTargets
1085 else LoadUpTo (GHC.mkModuleName m)
1088 doLoad :: Session -> Bool -> ([Module],[Module]) -> LoadHowMuch -> GHCi SuccessFlag
1089 doLoad session retain_context prev_context howmuch = do
1090 -- turn off breakpoints before we load: we can't turn them off later, because
1091 -- the ModBreaks will have gone away.
1092 discardActiveBreakPoints
1093 ok <- io (GHC.load session howmuch)
1094 afterLoad ok session retain_context prev_context
1097 afterLoad :: SuccessFlag -> Session -> Bool -> ([Module],[Module]) -> GHCi ()
1098 afterLoad ok session retain_context prev_context = do
1099 revertCAFs -- always revert CAFs on load.
1101 loaded_mod_summaries <- getLoadedModules session
1102 let loaded_mods = map GHC.ms_mod loaded_mod_summaries
1103 loaded_mod_names = map GHC.moduleName loaded_mods
1104 modulesLoadedMsg ok loaded_mod_names
1106 setContextAfterLoad session prev_context retain_context loaded_mod_summaries
1109 setContextAfterLoad :: Session -> ([Module],[Module]) -> Bool -> [GHC.ModSummary] -> GHCi ()
1110 setContextAfterLoad session prev keep_ctxt [] = do
1111 prel_mod <- getPrelude
1112 setContextKeepingPackageModules session prev keep_ctxt ([], [prel_mod])
1113 setContextAfterLoad session prev keep_ctxt ms = do
1114 -- load a target if one is available, otherwise load the topmost module.
1115 targets <- io (GHC.getTargets session)
1116 case [ m | Just m <- map (findTarget ms) targets ] of
1118 let graph' = flattenSCCs (GHC.topSortModuleGraph True ms Nothing) in
1119 load_this (last graph')
1124 = case filter (`matches` t) ms of
1128 summary `matches` Target (TargetModule m) _
1129 = GHC.ms_mod_name summary == m
1130 summary `matches` Target (TargetFile f _) _
1131 | Just f' <- GHC.ml_hs_file (GHC.ms_location summary) = f == f'
1135 load_this summary | m <- GHC.ms_mod summary = do
1136 b <- io (GHC.moduleIsInterpreted session m)
1137 if b then setContextKeepingPackageModules session prev keep_ctxt ([m], [])
1139 prel_mod <- getPrelude
1140 setContextKeepingPackageModules session prev keep_ctxt ([],[prel_mod,m])
1142 -- | Keep any package modules (except Prelude) when changing the context.
1143 setContextKeepingPackageModules
1145 -> ([Module],[Module]) -- previous context
1146 -> Bool -- re-execute :module commands
1147 -> ([Module],[Module]) -- new context
1149 setContextKeepingPackageModules session prev_context keep_ctxt (as,bs) = do
1150 let (_,bs0) = prev_context
1151 prel_mod <- getPrelude
1152 let pkg_modules = filter (\p -> not (isHomeModule p) && p /= prel_mod) bs0
1153 let bs1 = if null as then nub (prel_mod : bs) else bs
1154 io $ GHC.setContext session as (nub (bs1 ++ pkg_modules))
1158 mapM_ (playCtxtCmd False) (remembered_ctx st)
1161 setGHCiState st{ remembered_ctx = [] }
1163 isHomeModule :: Module -> Bool
1164 isHomeModule mod = GHC.modulePackageId mod == mainPackageId
1166 modulesLoadedMsg :: SuccessFlag -> [ModuleName] -> GHCi ()
1167 modulesLoadedMsg ok mods = do
1168 dflags <- getDynFlags
1169 when (verbosity dflags > 0) $ do
1171 | null mods = text "none."
1172 | otherwise = hsep (
1173 punctuate comma (map ppr mods)) <> text "."
1176 io (putStrLn (showSDoc (text "Failed, modules loaded: " <> mod_commas)))
1178 io (putStrLn (showSDoc (text "Ok, modules loaded: " <> mod_commas)))
1181 typeOfExpr :: String -> GHCi ()
1183 = do cms <- getSession
1184 maybe_ty <- io (GHC.exprType cms str)
1186 Nothing -> return ()
1187 Just ty -> do dflags <- getDynFlags
1188 let pefas = dopt Opt_PrintExplicitForalls dflags
1189 printForUser $ text str <+> dcolon
1190 <+> pprTypeForUser pefas ty
1192 kindOfType :: String -> GHCi ()
1194 = do cms <- getSession
1195 maybe_ty <- io (GHC.typeKind cms str)
1197 Nothing -> return ()
1198 Just ty -> printForUser $ text str <+> dcolon <+> ppr ty
1200 quit :: String -> GHCi Bool
1201 quit _ = return True
1203 shellEscape :: String -> GHCi Bool
1204 shellEscape str = io (system str >> return False)
1206 -----------------------------------------------------------------------------
1207 -- Browsing a module's contents
1209 browseCmd :: Bool -> String -> GHCi ()
1212 ['*':s] | looksLikeModuleName s -> do
1213 m <- wantInterpretedModule s
1214 browseModule bang m False
1215 [s] | looksLikeModuleName s -> do
1217 browseModule bang m True
1220 (as,bs) <- io $ GHC.getContext s
1221 -- Guess which module the user wants to browse. Pick
1222 -- modules that are interpreted first. The most
1223 -- recently-added module occurs last, it seems.
1225 (as@(_:_), _) -> browseModule bang (last as) True
1226 ([], bs@(_:_)) -> browseModule bang (last bs) True
1227 ([], []) -> throwDyn (CmdLineError ":browse: no current module")
1228 _ -> throwDyn (CmdLineError "syntax: :browse <module>")
1230 -- without bang, show items in context of their parents and omit children
1231 -- with bang, show class methods and data constructors separately, and
1232 -- indicate import modules, to aid qualifying unqualified names
1233 -- with sorted, sort items alphabetically
1234 browseModule :: Bool -> Module -> Bool -> GHCi ()
1235 browseModule bang modl exports_only = do
1237 -- :browse! reports qualifiers wrt current context
1238 current_unqual <- io (GHC.getPrintUnqual s)
1239 -- Temporarily set the context to the module we're interested in,
1240 -- just so we can get an appropriate PrintUnqualified
1241 (as,bs) <- io (GHC.getContext s)
1242 prel_mod <- getPrelude
1243 io (if exports_only then GHC.setContext s [] [prel_mod,modl]
1244 else GHC.setContext s [modl] [])
1245 target_unqual <- io (GHC.getPrintUnqual s)
1246 io (GHC.setContext s as bs)
1248 let unqual = if bang then current_unqual else target_unqual
1250 mb_mod_info <- io $ GHC.getModuleInfo s modl
1252 Nothing -> throwDyn (CmdLineError ("unknown module: " ++
1253 GHC.moduleNameString (GHC.moduleName modl)))
1255 dflags <- getDynFlags
1257 | exports_only = GHC.modInfoExports mod_info
1258 | otherwise = GHC.modInfoTopLevelScope mod_info
1261 -- sort alphabetically name, but putting
1262 -- locally-defined identifiers first.
1263 -- We would like to improve this; see #1799.
1264 sorted_names = loc_sort local ++ occ_sort external
1266 (local,external) = partition ((==modl) . nameModule) names
1267 occ_sort = sortBy (compare `on` nameOccName)
1268 -- try to sort by src location. If the first name in
1269 -- our list has a good source location, then they all should.
1271 | n:_ <- names, isGoodSrcSpan (nameSrcSpan n)
1272 = sortBy (compare `on` nameSrcSpan) names
1276 mb_things <- io $ mapM (GHC.lookupName s) sorted_names
1277 let filtered_things = filterOutChildren (\t -> t) (catMaybes mb_things)
1279 rdr_env <- io $ GHC.getGRE s
1281 let pefas = dopt Opt_PrintExplicitForalls dflags
1282 things | bang = catMaybes mb_things
1283 | otherwise = filtered_things
1284 pretty | bang = pprTyThing
1285 | otherwise = pprTyThingInContext
1287 labels [] = text "-- not currently imported"
1288 labels l = text $ intercalate "\n" $ map qualifier l
1289 qualifier = maybe "-- defined locally"
1290 (("-- imported via "++) . intercalate ", "
1291 . map GHC.moduleNameString)
1292 importInfo = RdrName.getGRE_NameQualifier_maybes rdr_env
1293 modNames = map (importInfo . GHC.getName) things
1295 -- annotate groups of imports with their import modules
1296 -- the default ordering is somewhat arbitrary, so we group
1297 -- by header and sort groups; the names themselves should
1298 -- really come in order of source appearance.. (trac #1799)
1299 annotate mts = concatMap (\(m,ts)->labels m:ts)
1300 $ sortBy cmpQualifiers $ group mts
1301 where cmpQualifiers =
1302 compare `on` (map (fmap (map moduleNameFS)) . fst)
1304 group mts@((m,_):_) = (m,map snd g) : group ng
1305 where (g,ng) = partition ((==m).fst) mts
1307 let prettyThings = map (pretty pefas) things
1308 prettyThings' | bang = annotate $ zip modNames prettyThings
1309 | otherwise = prettyThings
1310 io (putStrLn $ showSDocForUser unqual (vcat prettyThings'))
1311 -- ToDo: modInfoInstances currently throws an exception for
1312 -- package modules. When it works, we can do this:
1313 -- $$ vcat (map GHC.pprInstance (GHC.modInfoInstances mod_info))
1315 -----------------------------------------------------------------------------
1316 -- Setting the module context
1318 setContext :: String -> GHCi ()
1320 | all sensible strs = do
1321 playCtxtCmd True (cmd, as, bs)
1323 setGHCiState st{ remembered_ctx = remembered_ctx st ++ [(cmd,as,bs)] }
1324 | otherwise = throwDyn (CmdLineError "syntax: :module [+/-] [*]M1 ... [*]Mn")
1326 (cmd, strs, as, bs) =
1328 '+':stuff -> rest AddModules stuff
1329 '-':stuff -> rest RemModules stuff
1330 stuff -> rest SetContext stuff
1332 rest cmd stuff = (cmd, strs, as, bs)
1333 where strs = words stuff
1334 (as,bs) = partitionWith starred strs
1336 sensible ('*':m) = looksLikeModuleName m
1337 sensible m = looksLikeModuleName m
1339 starred ('*':m) = Left m
1342 playCtxtCmd :: Bool -> (CtxtCmd, [String], [String]) -> GHCi ()
1343 playCtxtCmd fail (cmd, as, bs)
1346 (as',bs') <- do_checks fail
1347 (prev_as,prev_bs) <- io $ GHC.getContext s
1351 prel_mod <- getPrelude
1352 let bs'' = if null as && prel_mod `notElem` bs' then prel_mod:bs'
1356 let as_to_add = as' \\ (prev_as ++ prev_bs)
1357 bs_to_add = bs' \\ (prev_as ++ prev_bs)
1358 return (prev_as ++ as_to_add, prev_bs ++ bs_to_add)
1360 let new_as = prev_as \\ (as' ++ bs')
1361 new_bs = prev_bs \\ (as' ++ bs')
1362 return (new_as, new_bs)
1363 io $ GHC.setContext s new_as new_bs
1366 as' <- mapM wantInterpretedModule as
1367 bs' <- mapM lookupModule bs
1369 do_checks False = do
1370 as' <- mapM (trymaybe . wantInterpretedModule) as
1371 bs' <- mapM (trymaybe . lookupModule) bs
1372 return (catMaybes as', catMaybes bs')
1377 Left _ -> return Nothing
1378 Right a -> return (Just a)
1380 ----------------------------------------------------------------------------
1383 -- set options in the interpreter. Syntax is exactly the same as the
1384 -- ghc command line, except that certain options aren't available (-C,
1387 -- This is pretty fragile: most options won't work as expected. ToDo:
1388 -- figure out which ones & disallow them.
1390 setCmd :: String -> GHCi ()
1392 = do st <- getGHCiState
1393 let opts = options st
1394 io $ putStrLn (showSDoc (
1395 text "options currently set: " <>
1398 else hsep (map (\o -> char '+' <> text (optToStr o)) opts)
1400 dflags <- getDynFlags
1401 io $ putStrLn (showSDoc (
1402 vcat (text "GHCi-specific dynamic flag settings:"
1403 :map (flagSetting dflags) ghciFlags)
1405 io $ putStrLn (showSDoc (
1406 vcat (text "other dynamic, non-language, flag settings:"
1407 :map (flagSetting dflags) nonLanguageDynFlags)
1409 where flagSetting dflags (str, f, _)
1410 | dopt f dflags = text " " <> text "-f" <> text str
1411 | otherwise = text " " <> text "-fno-" <> text str
1412 (ghciFlags,others) = partition (\(_, f, _) -> f `elem` flags)
1414 nonLanguageDynFlags = filterOut (\(_, f, _) -> f `elem` languageOptions)
1416 flags = [Opt_PrintExplicitForalls
1417 ,Opt_PrintBindResult
1418 ,Opt_BreakOnException
1420 ,Opt_PrintEvldWithShow
1423 = case getCmd str of
1424 Right ("args", rest) ->
1426 Left err -> io (hPutStrLn stderr err)
1427 Right args -> setArgs args
1428 Right ("prog", rest) ->
1430 Right [prog] -> setProg prog
1431 _ -> io (hPutStrLn stderr "syntax: :set prog <progname>")
1432 Right ("prompt", rest) -> setPrompt $ dropWhile isSpace rest
1433 Right ("editor", rest) -> setEditor $ dropWhile isSpace rest
1434 Right ("stop", rest) -> setStop $ dropWhile isSpace rest
1435 _ -> case toArgs str of
1436 Left err -> io (hPutStrLn stderr err)
1437 Right wds -> setOptions wds
1439 setArgs, setOptions :: [String] -> GHCi ()
1440 setProg, setEditor, setStop, setPrompt :: String -> GHCi ()
1444 setGHCiState st{ args = args }
1448 setGHCiState st{ progname = prog }
1452 setGHCiState st{ editor = cmd }
1454 setStop str@(c:_) | isDigit c
1455 = do let (nm_str,rest) = break (not.isDigit) str
1458 let old_breaks = breaks st
1459 if all ((/= nm) . fst) old_breaks
1460 then printForUser (text "Breakpoint" <+> ppr nm <+>
1461 text "does not exist")
1463 let new_breaks = map fn old_breaks
1464 fn (i,loc) | i == nm = (i,loc { onBreakCmd = dropWhile isSpace rest })
1465 | otherwise = (i,loc)
1466 setGHCiState st{ breaks = new_breaks }
1469 setGHCiState st{ stop = cmd }
1471 setPrompt value = do
1474 then io $ hPutStrLn stderr $ "syntax: :set prompt <prompt>, currently \"" ++ prompt st ++ "\""
1475 else setGHCiState st{ prompt = remQuotes value }
1477 remQuotes ('\"':xs) | not (null xs) && last xs == '\"' = init xs
1481 do -- first, deal with the GHCi opts (+s, +t, etc.)
1482 let (plus_opts, minus_opts) = partitionWith isPlus wds
1483 mapM_ setOpt plus_opts
1484 -- then, dynamic flags
1485 newDynFlags minus_opts
1487 newDynFlags :: [String] -> GHCi ()
1488 newDynFlags minus_opts = do
1489 dflags <- getDynFlags
1490 let pkg_flags = packageFlags dflags
1491 (dflags', leftovers, warns) <- io $ GHC.parseDynamicFlags dflags minus_opts
1492 io $ handleFlagWarnings dflags' warns
1494 if (not (null leftovers))
1495 then throwDyn (CmdLineError ("unrecognised flags: " ++
1499 new_pkgs <- setDynFlags dflags'
1501 -- if the package flags changed, we should reset the context
1502 -- and link the new packages.
1503 dflags <- getDynFlags
1504 when (packageFlags dflags /= pkg_flags) $ do
1505 io $ hPutStrLn stderr "package flags have changed, ressetting and loading new packages..."
1506 session <- getSession
1507 io (GHC.setTargets session [])
1508 io (GHC.load session LoadAllTargets)
1509 io (linkPackages dflags new_pkgs)
1510 -- package flags changed, we can't re-use any of the old context
1511 setContextAfterLoad session ([],[]) False []
1515 unsetOptions :: String -> GHCi ()
1517 = do -- first, deal with the GHCi opts (+s, +t, etc.)
1518 let opts = words str
1519 (minus_opts, rest1) = partition isMinus opts
1520 (plus_opts, rest2) = partitionWith isPlus rest1
1522 if (not (null rest2))
1523 then io (putStrLn ("unknown option: '" ++ head rest2 ++ "'"))
1526 mapM_ unsetOpt plus_opts
1528 let no_flag ('-':'f':rest) = return ("-fno-" ++ rest)
1529 no_flag f = throwDyn (ProgramError ("don't know how to reverse " ++ f))
1531 no_flags <- mapM no_flag minus_opts
1532 newDynFlags no_flags
1534 isMinus :: String -> Bool
1535 isMinus ('-':_) = True
1538 isPlus :: String -> Either String String
1539 isPlus ('+':opt) = Left opt
1540 isPlus other = Right other
1542 setOpt, unsetOpt :: String -> GHCi ()
1545 = case strToGHCiOpt str of
1546 Nothing -> io (putStrLn ("unknown option: '" ++ str ++ "'"))
1547 Just o -> setOption o
1550 = case strToGHCiOpt str of
1551 Nothing -> io (putStrLn ("unknown option: '" ++ str ++ "'"))
1552 Just o -> unsetOption o
1554 strToGHCiOpt :: String -> (Maybe GHCiOption)
1555 strToGHCiOpt "s" = Just ShowTiming
1556 strToGHCiOpt "t" = Just ShowType
1557 strToGHCiOpt "r" = Just RevertCAFs
1558 strToGHCiOpt _ = Nothing
1560 optToStr :: GHCiOption -> String
1561 optToStr ShowTiming = "s"
1562 optToStr ShowType = "t"
1563 optToStr RevertCAFs = "r"
1565 -- ---------------------------------------------------------------------------
1568 showCmd :: String -> GHCi ()
1572 ["args"] -> io $ putStrLn (show (args st))
1573 ["prog"] -> io $ putStrLn (show (progname st))
1574 ["prompt"] -> io $ putStrLn (show (prompt st))
1575 ["editor"] -> io $ putStrLn (show (editor st))
1576 ["stop"] -> io $ putStrLn (show (stop st))
1577 ["modules" ] -> showModules
1578 ["bindings"] -> showBindings
1579 ["linker"] -> io showLinkerState
1580 ["breaks"] -> showBkptTable
1581 ["context"] -> showContext
1582 ["packages"] -> showPackages
1583 ["languages"] -> showLanguages
1584 _ -> throwDyn (CmdLineError ("syntax: :show [ args | prog | prompt | editor | stop | modules | bindings\n"++
1585 " | breaks | context | packages | languages ]"))
1587 showModules :: GHCi ()
1589 session <- getSession
1590 loaded_mods <- getLoadedModules session
1591 -- we want *loaded* modules only, see #1734
1592 let show_one ms = do m <- io (GHC.showModule session ms); io (putStrLn m)
1593 mapM_ show_one loaded_mods
1595 getLoadedModules :: GHC.Session -> GHCi [GHC.ModSummary]
1596 getLoadedModules session = do
1597 graph <- io (GHC.getModuleGraph session)
1598 filterM (io . GHC.isLoaded session . GHC.ms_mod_name) graph
1600 showBindings :: GHCi ()
1603 bindings <- io (GHC.getBindings s)
1604 docs <- io$ pprTypeAndContents s
1605 [ id | AnId id <- sortBy compareTyThings bindings]
1606 printForUserPartWay docs
1608 compareTyThings :: TyThing -> TyThing -> Ordering
1609 t1 `compareTyThings` t2 = getName t1 `compareNames` getName t2
1611 printTyThing :: TyThing -> GHCi ()
1612 printTyThing tyth = do dflags <- getDynFlags
1613 let pefas = dopt Opt_PrintExplicitForalls dflags
1614 printForUser (pprTyThing pefas tyth)
1616 showBkptTable :: GHCi ()
1619 printForUser $ prettyLocations (breaks st)
1621 showContext :: GHCi ()
1623 session <- getSession
1624 resumes <- io $ GHC.getResumeContext session
1625 printForUser $ vcat (map pp_resume (reverse resumes))
1628 ptext (sLit "--> ") <> text (GHC.resumeStmt resume)
1629 $$ nest 2 (ptext (sLit "Stopped at") <+> ppr (GHC.resumeSpan resume))
1631 showPackages :: GHCi ()
1633 pkg_flags <- fmap packageFlags getDynFlags
1634 io $ putStrLn $ showSDoc $ vcat $
1635 text ("active package flags:"++if null pkg_flags then " none" else "")
1636 : map showFlag pkg_flags
1637 pkg_ids <- fmap (preloadPackages . pkgState) getDynFlags
1638 io $ putStrLn $ showSDoc $ vcat $
1639 text "packages currently loaded:"
1640 : map (nest 2 . text . packageIdString)
1641 (sortBy (compare `on` packageIdFS) pkg_ids)
1642 where showFlag (ExposePackage p) = text $ " -package " ++ p
1643 showFlag (HidePackage p) = text $ " -hide-package " ++ p
1644 showFlag (IgnorePackage p) = text $ " -ignore-package " ++ p
1646 showLanguages :: GHCi ()
1648 dflags <- getDynFlags
1649 io $ putStrLn $ showSDoc $ vcat $
1650 text "active language flags:" :
1651 [text (" -X" ++ str) | (str, f, _) <- DynFlags.xFlags, dopt f dflags]
1653 -- -----------------------------------------------------------------------------
1656 completeNone :: String -> IO [String]
1657 completeNone _w = return []
1659 completeMacro, completeIdentifier, completeModule,
1660 completeHomeModule, completeSetOptions, completeFilename,
1661 completeHomeModuleOrFile
1662 :: String -> IO [String]
1665 completeWord :: String -> Int -> Int -> IO (Maybe (String, [String]))
1666 completeWord w start end = do
1667 line <- Readline.getLineBuffer
1668 let line_words = words (dropWhile isSpace line)
1670 ':':_ | all isSpace (take (start-1) line) -> wrapCompleter completeCmd w
1672 | ((':':c) : _) <- line_words -> do
1673 completionVars <- lookupCompletionVars c
1674 case completionVars of
1675 (Nothing,complete) -> wrapCompleter complete w
1676 (Just breakChars,complete)
1677 -> let (n,w') = selectWord
1678 (words' (`elem` breakChars) 0 line)
1679 complete' w = do rets <- complete w
1680 return (map (drop n) rets)
1681 in wrapCompleter complete' w'
1682 | ("import" : _) <- line_words ->
1683 wrapCompleter completeModule w
1685 --printf "complete %s, start = %d, end = %d\n" w start end
1686 wrapCompleter completeIdentifier w
1687 where words' _ _ [] = []
1688 words' isBreak n str = let (w,r) = break isBreak str
1689 (s,r') = span isBreak r
1690 in (n,w):words' isBreak (n+length w+length s) r'
1691 -- In a Haskell expression we want to parse 'a-b' as three words
1692 -- where a compiler flag (e.g. -ddump-simpl) should
1693 -- only be a single word.
1694 selectWord [] = (0,w)
1695 selectWord ((offset,x):xs)
1696 | offset+length x >= start = (start-offset,take (end-offset) x)
1697 | otherwise = selectWord xs
1699 lookupCompletionVars ('!':_) = return (Just filenameWordBreakChars,
1701 lookupCompletionVars c = do
1702 maybe_cmd <- lookupCommand' c
1704 Just (_,_,ws,f) -> return (ws,f)
1705 Nothing -> return (Just filenameWordBreakChars,
1709 completeCmd :: String -> IO [String]
1711 cmds <- readIORef macros_ref
1712 return (filter (w `isPrefixOf`) (map (':':)
1713 (map cmdName (builtin_commands ++ cmds))))
1715 completeMacro w = do
1716 cmds <- readIORef macros_ref
1717 return (filter (w `isPrefixOf`) (map cmdName cmds))
1719 completeIdentifier w = do
1721 rdrs <- GHC.getRdrNamesInScope s
1722 return (filter (w `isPrefixOf`) (map (showSDoc.ppr) rdrs))
1724 completeModule w = do
1726 dflags <- GHC.getSessionDynFlags s
1727 let pkg_mods = allExposedModules dflags
1728 return (filter (w `isPrefixOf`) (map (showSDoc.ppr) pkg_mods))
1730 completeHomeModule w = do
1732 g <- GHC.getModuleGraph s
1733 let home_mods = map GHC.ms_mod_name g
1734 return (filter (w `isPrefixOf`) (map (showSDoc.ppr) home_mods))
1736 completeSetOptions w = do
1737 return (filter (w `isPrefixOf`) options)
1738 where options = "args":"prog":allFlags
1740 completeFilename w = do
1741 ws <- Readline.filenameCompletionFunction w
1743 -- If we only found one result, and it's a directory,
1744 -- add a trailing slash.
1746 isDir <- expandPathIO file >>= doesDirectoryExist
1747 if isDir && last file /= '/'
1748 then return [file ++ "/"]
1753 completeHomeModuleOrFile = unionComplete completeHomeModule completeFilename
1755 unionComplete :: (String -> IO [String]) -> (String -> IO [String]) -> String -> IO [String]
1756 unionComplete f1 f2 w = do
1761 wrapCompleter :: (String -> IO [String]) -> String -> IO (Maybe (String,[String]))
1762 wrapCompleter fun w = do
1765 [] -> Readline.setAttemptedCompletionOver True >> return Nothing
1766 [x] -> -- Add a trailing space, unless it already has an appended slash.
1767 let appended = if last x == '/' then x else x ++ " "
1768 in return (Just (appended,[]))
1769 xs -> case getCommonPrefix xs of
1770 "" -> return (Just ("",xs))
1771 pref -> return (Just (pref,xs))
1773 getCommonPrefix :: [String] -> String
1774 getCommonPrefix [] = ""
1775 getCommonPrefix (s:ss) = foldl common s ss
1776 where common _s "" = ""
1778 common (c:cs) (d:ds)
1779 | c == d = c : common cs ds
1782 allExposedModules :: DynFlags -> [ModuleName]
1783 allExposedModules dflags
1784 = concat (map exposedModules (filter exposed (eltsUFM pkg_db)))
1786 pkg_db = pkgIdMap (pkgState dflags)
1788 completeMacro = completeNone
1789 completeIdentifier = completeNone
1790 completeModule = completeNone
1791 completeHomeModule = completeNone
1792 completeSetOptions = completeNone
1793 completeFilename = completeNone
1794 completeHomeModuleOrFile=completeNone
1797 -- ---------------------------------------------------------------------------
1798 -- User code exception handling
1800 -- This is the exception handler for exceptions generated by the
1801 -- user's code and exceptions coming from children sessions;
1802 -- it normally just prints out the exception. The
1803 -- handler must be recursive, in case showing the exception causes
1804 -- more exceptions to be raised.
1806 -- Bugfix: if the user closed stdout or stderr, the flushing will fail,
1807 -- raising another exception. We therefore don't put the recursive
1808 -- handler arond the flushing operation, so if stderr is closed
1809 -- GHCi will just die gracefully rather than going into an infinite loop.
1810 handler :: Exception -> GHCi Bool
1812 handler exception = do
1814 io installSignalHandlers
1815 ghciHandle handler (showException exception >> return False)
1817 showException :: Exception -> GHCi ()
1818 showException (DynException dyn) =
1819 case fromDynamic dyn of
1820 Nothing -> io (putStrLn ("*** Exception: (unknown)"))
1821 Just Interrupted -> io (putStrLn "Interrupted.")
1822 Just (CmdLineError s) -> io (putStrLn s) -- omit the location for CmdLineError
1823 Just ph@PhaseFailed{} -> io (putStrLn (showGhcException ph "")) -- ditto
1824 Just other_ghc_ex -> io (print other_ghc_ex)
1826 showException other_exception
1827 = io (putStrLn ("*** Exception: " ++ show other_exception))
1829 -----------------------------------------------------------------------------
1830 -- recursive exception handlers
1832 -- Don't forget to unblock async exceptions in the handler, or if we're
1833 -- in an exception loop (eg. let a = error a in a) the ^C exception
1834 -- may never be delivered. Thanks to Marcin for pointing out the bug.
1836 ghciHandle :: (Exception -> GHCi a) -> GHCi a -> GHCi a
1837 ghciHandle h (GHCi m) = GHCi $ \s ->
1838 Exception.catch (m s)
1839 (\e -> unGHCi (ghciUnblock (h e)) s)
1841 ghciUnblock :: GHCi a -> GHCi a
1842 ghciUnblock (GHCi a) = GHCi $ \s -> Exception.unblock (a s)
1844 ghciTry :: GHCi a -> GHCi (Either Exception a)
1845 ghciTry (GHCi m) = GHCi $ \s -> Exception.try (m s)
1847 -- ----------------------------------------------------------------------------
1850 expandPath :: String -> GHCi String
1851 expandPath path = io (expandPathIO path)
1853 expandPathIO :: String -> IO String
1855 case dropWhile isSpace path of
1857 tilde <- getHomeDirectory -- will fail if HOME not defined
1858 return (tilde ++ '/':d)
1862 wantInterpretedModule :: String -> GHCi Module
1863 wantInterpretedModule str = do
1864 session <- getSession
1865 modl <- lookupModule str
1866 is_interpreted <- io (GHC.moduleIsInterpreted session modl)
1867 when (not is_interpreted) $
1868 throwDyn (CmdLineError ("module '" ++ str ++ "' is not interpreted"))
1871 wantNameFromInterpretedModule :: (Name -> SDoc -> GHCi ()) -> String
1872 -> (Name -> GHCi ())
1874 wantNameFromInterpretedModule noCanDo str and_then = do
1875 session <- getSession
1876 names <- io $ GHC.parseName session str
1880 let modl = GHC.nameModule n
1881 if not (GHC.isExternalName n)
1882 then noCanDo n $ ppr n <>
1883 text " is not defined in an interpreted module"
1885 is_interpreted <- io (GHC.moduleIsInterpreted session modl)
1886 if not is_interpreted
1887 then noCanDo n $ text "module " <> ppr modl <>
1888 text " is not interpreted"
1891 -- -----------------------------------------------------------------------------
1892 -- commands for debugger
1894 sprintCmd, printCmd, forceCmd :: String -> GHCi ()
1895 sprintCmd = pprintCommand False False
1896 printCmd = pprintCommand True False
1897 forceCmd = pprintCommand False True
1899 pprintCommand :: Bool -> Bool -> String -> GHCi ()
1900 pprintCommand bind force str = do
1901 session <- getSession
1902 io $ pprintClosureCommand session bind force str
1904 stepCmd :: String -> GHCi ()
1905 stepCmd [] = doContinue (const True) GHC.SingleStep
1906 stepCmd expression = do runStmt expression GHC.SingleStep; return ()
1908 stepLocalCmd :: String -> GHCi ()
1909 stepLocalCmd [] = do
1910 mb_span <- getCurrentBreakSpan
1912 Nothing -> stepCmd []
1914 Just mod <- getCurrentBreakModule
1915 current_toplevel_decl <- enclosingTickSpan mod loc
1916 doContinue (`isSubspanOf` current_toplevel_decl) GHC.SingleStep
1918 stepLocalCmd expression = stepCmd expression
1920 stepModuleCmd :: String -> GHCi ()
1921 stepModuleCmd [] = do
1922 mb_span <- getCurrentBreakSpan
1924 Nothing -> stepCmd []
1926 Just span <- getCurrentBreakSpan
1927 let f some_span = optSrcSpanFileName span == optSrcSpanFileName some_span
1928 doContinue f GHC.SingleStep
1930 stepModuleCmd expression = stepCmd expression
1932 -- | Returns the span of the largest tick containing the srcspan given
1933 enclosingTickSpan :: Module -> SrcSpan -> GHCi SrcSpan
1934 enclosingTickSpan mod src = do
1935 ticks <- getTickArray mod
1936 let line = srcSpanStartLine src
1937 ASSERT (inRange (bounds ticks) line) do
1938 let enclosing_spans = [ span | (_,span) <- ticks ! line
1939 , srcSpanEnd span >= srcSpanEnd src]
1940 return . head . sortBy leftmost_largest $ enclosing_spans
1942 traceCmd :: String -> GHCi ()
1943 traceCmd [] = doContinue (const True) GHC.RunAndLogSteps
1944 traceCmd expression = do runStmt expression GHC.RunAndLogSteps; return ()
1946 continueCmd :: String -> GHCi ()
1947 continueCmd = noArgs $ doContinue (const True) GHC.RunToCompletion
1949 -- doContinue :: SingleStep -> GHCi ()
1950 doContinue :: (SrcSpan -> Bool) -> SingleStep -> GHCi ()
1951 doContinue pred step = do
1952 runResult <- resume step
1953 afterRunStmt pred runResult
1956 abandonCmd :: String -> GHCi ()
1957 abandonCmd = noArgs $ do
1959 b <- io $ GHC.abandon s -- the prompt will change to indicate the new context
1960 when (not b) $ io $ putStrLn "There is no computation running."
1963 deleteCmd :: String -> GHCi ()
1964 deleteCmd argLine = do
1965 deleteSwitch $ words argLine
1967 deleteSwitch :: [String] -> GHCi ()
1969 io $ putStrLn "The delete command requires at least one argument."
1970 -- delete all break points
1971 deleteSwitch ("*":_rest) = discardActiveBreakPoints
1972 deleteSwitch idents = do
1973 mapM_ deleteOneBreak idents
1975 deleteOneBreak :: String -> GHCi ()
1977 | all isDigit str = deleteBreak (read str)
1978 | otherwise = return ()
1980 historyCmd :: String -> GHCi ()
1982 | null arg = history 20
1983 | all isDigit arg = history (read arg)
1984 | otherwise = io $ putStrLn "Syntax: :history [num]"
1988 resumes <- io $ GHC.getResumeContext s
1990 [] -> io $ putStrLn "Not stopped at a breakpoint"
1992 let hist = GHC.resumeHistory r
1993 (took,rest) = splitAt num hist
1995 [] -> io $ putStrLn $
1996 "Empty history. Perhaps you forgot to use :trace?"
1998 spans <- mapM (io . GHC.getHistorySpan s) took
1999 let nums = map (printf "-%-3d:") [(1::Int)..]
2000 names = map GHC.historyEnclosingDecl took
2001 printForUser (vcat(zipWith3
2002 (\x y z -> x <+> y <+> z)
2004 (map (bold . ppr) names)
2005 (map (parens . ppr) spans)))
2006 io $ putStrLn $ if null rest then "<end of history>" else "..."
2008 bold :: SDoc -> SDoc
2009 bold c | do_bold = text start_bold <> c <> text end_bold
2012 backCmd :: String -> GHCi ()
2013 backCmd = noArgs $ do
2015 (names, _, span) <- io $ GHC.back s
2016 printForUser $ ptext (sLit "Logged breakpoint at") <+> ppr span
2017 printTypeOfNames s names
2018 -- run the command set with ":set stop <cmd>"
2020 enqueueCommands [stop st]
2022 forwardCmd :: String -> GHCi ()
2023 forwardCmd = noArgs $ do
2025 (names, ix, span) <- io $ GHC.forward s
2026 printForUser $ (if (ix == 0)
2027 then ptext (sLit "Stopped at")
2028 else ptext (sLit "Logged breakpoint at")) <+> ppr span
2029 printTypeOfNames s names
2030 -- run the command set with ":set stop <cmd>"
2032 enqueueCommands [stop st]
2034 -- handle the "break" command
2035 breakCmd :: String -> GHCi ()
2036 breakCmd argLine = do
2037 session <- getSession
2038 breakSwitch session $ words argLine
2040 breakSwitch :: Session -> [String] -> GHCi ()
2041 breakSwitch _session [] = do
2042 io $ putStrLn "The break command requires at least one argument."
2043 breakSwitch session (arg1:rest)
2044 | looksLikeModuleName arg1 && not (null rest) = do
2045 mod <- wantInterpretedModule arg1
2046 breakByModule mod rest
2047 | all isDigit arg1 = do
2048 (toplevel, _) <- io $ GHC.getContext session
2050 (mod : _) -> breakByModuleLine mod (read arg1) rest
2052 io $ putStrLn "Cannot find default module for breakpoint."
2053 io $ putStrLn "Perhaps no modules are loaded for debugging?"
2054 | otherwise = do -- try parsing it as an identifier
2055 wantNameFromInterpretedModule noCanDo arg1 $ \name -> do
2056 let loc = GHC.srcSpanStart (GHC.nameSrcSpan name)
2057 if GHC.isGoodSrcLoc loc
2058 then findBreakAndSet (GHC.nameModule name) $
2059 findBreakByCoord (Just (GHC.srcLocFile loc))
2060 (GHC.srcLocLine loc,
2062 else noCanDo name $ text "can't find its location: " <> ppr loc
2064 noCanDo n why = printForUser $
2065 text "cannot set breakpoint on " <> ppr n <> text ": " <> why
2067 breakByModule :: Module -> [String] -> GHCi ()
2068 breakByModule mod (arg1:rest)
2069 | all isDigit arg1 = do -- looks like a line number
2070 breakByModuleLine mod (read arg1) rest
2074 breakByModuleLine :: Module -> Int -> [String] -> GHCi ()
2075 breakByModuleLine mod line args
2076 | [] <- args = findBreakAndSet mod $ findBreakByLine line
2077 | [col] <- args, all isDigit col =
2078 findBreakAndSet mod $ findBreakByCoord Nothing (line, read col)
2079 | otherwise = breakSyntax
2082 breakSyntax = throwDyn (CmdLineError "Syntax: :break [<mod>] <line> [<column>]")
2084 findBreakAndSet :: Module -> (TickArray -> Maybe (Int, SrcSpan)) -> GHCi ()
2085 findBreakAndSet mod lookupTickTree = do
2086 tickArray <- getTickArray mod
2087 (breakArray, _) <- getModBreak mod
2088 case lookupTickTree tickArray of
2089 Nothing -> io $ putStrLn $ "No breakpoints found at that location."
2090 Just (tick, span) -> do
2091 success <- io $ setBreakFlag True breakArray tick
2095 recordBreak $ BreakLocation
2102 text "Breakpoint " <> ppr nm <>
2104 then text " was already set at " <> ppr span
2105 else text " activated at " <> ppr span
2107 printForUser $ text "Breakpoint could not be activated at"
2110 -- When a line number is specified, the current policy for choosing
2111 -- the best breakpoint is this:
2112 -- - the leftmost complete subexpression on the specified line, or
2113 -- - the leftmost subexpression starting on the specified line, or
2114 -- - the rightmost subexpression enclosing the specified line
2116 findBreakByLine :: Int -> TickArray -> Maybe (BreakIndex,SrcSpan)
2117 findBreakByLine line arr
2118 | not (inRange (bounds arr) line) = Nothing
2120 listToMaybe (sortBy (leftmost_largest `on` snd) complete) `mplus`
2121 listToMaybe (sortBy (leftmost_smallest `on` snd) incomplete) `mplus`
2122 listToMaybe (sortBy (rightmost `on` snd) ticks)
2126 starts_here = [ tick | tick@(_,span) <- ticks,
2127 GHC.srcSpanStartLine span == line ]
2129 (complete,incomplete) = partition ends_here starts_here
2130 where ends_here (_,span) = GHC.srcSpanEndLine span == line
2132 findBreakByCoord :: Maybe FastString -> (Int,Int) -> TickArray
2133 -> Maybe (BreakIndex,SrcSpan)
2134 findBreakByCoord mb_file (line, col) arr
2135 | not (inRange (bounds arr) line) = Nothing
2137 listToMaybe (sortBy (rightmost `on` snd) contains ++
2138 sortBy (leftmost_smallest `on` snd) after_here)
2142 -- the ticks that span this coordinate
2143 contains = [ tick | tick@(_,span) <- ticks, span `spans` (line,col),
2144 is_correct_file span ]
2146 is_correct_file span
2147 | Just f <- mb_file = GHC.srcSpanFile span == f
2150 after_here = [ tick | tick@(_,span) <- ticks,
2151 GHC.srcSpanStartLine span == line,
2152 GHC.srcSpanStartCol span >= col ]
2154 -- For now, use ANSI bold on terminals that we know support it.
2155 -- Otherwise, we add a line of carets under the active expression instead.
2156 -- In particular, on Windows and when running the testsuite (which sets
2157 -- TERM to vt100 for other reasons) we get carets.
2158 -- We really ought to use a proper termcap/terminfo library.
2160 do_bold = (`isPrefixOf` unsafePerformIO mTerm) `any` ["xterm", "linux"]
2161 where mTerm = System.Environment.getEnv "TERM"
2162 `Exception.catch` \_ -> return "TERM not set"
2164 start_bold :: String
2165 start_bold = "\ESC[1m"
2167 end_bold = "\ESC[0m"
2169 listCmd :: String -> GHCi ()
2171 mb_span <- getCurrentBreakSpan
2174 printForUser $ text "Not stopped at a breakpoint; nothing to list"
2176 | GHC.isGoodSrcSpan span -> io $ listAround span True
2179 resumes <- io $ GHC.getResumeContext s
2181 [] -> panic "No resumes"
2183 do let traceIt = case GHC.resumeHistory r of
2184 [] -> text "rerunning with :trace,"
2186 doWhat = traceIt <+> text ":back then :list"
2187 printForUser (text "Unable to list source for" <+>
2189 $$ text "Try" <+> doWhat)
2190 listCmd str = list2 (words str)
2192 list2 :: [String] -> GHCi ()
2193 list2 [arg] | all isDigit arg = do
2194 session <- getSession
2195 (toplevel, _) <- io $ GHC.getContext session
2197 [] -> io $ putStrLn "No module to list"
2198 (mod : _) -> listModuleLine mod (read arg)
2199 list2 [arg1,arg2] | looksLikeModuleName arg1, all isDigit arg2 = do
2200 mod <- wantInterpretedModule arg1
2201 listModuleLine mod (read arg2)
2203 wantNameFromInterpretedModule noCanDo arg $ \name -> do
2204 let loc = GHC.srcSpanStart (GHC.nameSrcSpan name)
2205 if GHC.isGoodSrcLoc loc
2207 tickArray <- getTickArray (GHC.nameModule name)
2208 let mb_span = findBreakByCoord (Just (GHC.srcLocFile loc))
2209 (GHC.srcLocLine loc, GHC.srcLocCol loc)
2212 Nothing -> io $ listAround (GHC.srcLocSpan loc) False
2213 Just (_,span) -> io $ listAround span False
2215 noCanDo name $ text "can't find its location: " <>
2218 noCanDo n why = printForUser $
2219 text "cannot list source code for " <> ppr n <> text ": " <> why
2221 io $ putStrLn "syntax: :list [<line> | <module> <line> | <identifier>]"
2223 listModuleLine :: Module -> Int -> GHCi ()
2224 listModuleLine modl line = do
2225 session <- getSession
2226 graph <- io (GHC.getModuleGraph session)
2227 let this = filter ((== modl) . GHC.ms_mod) graph
2229 [] -> panic "listModuleLine"
2231 let filename = fromJust (ml_hs_file (GHC.ms_location summ))
2232 loc = GHC.mkSrcLoc (mkFastString (filename)) line 0
2233 io $ listAround (GHC.srcLocSpan loc) False
2235 -- | list a section of a source file around a particular SrcSpan.
2236 -- If the highlight flag is True, also highlight the span using
2237 -- start_bold/end_bold.
2238 listAround :: SrcSpan -> Bool -> IO ()
2239 listAround span do_highlight = do
2240 contents <- BS.readFile (unpackFS file)
2242 lines = BS.split '\n' contents
2243 these_lines = take (line2 - line1 + 1 + pad_before + pad_after) $
2244 drop (line1 - 1 - pad_before) $ lines
2245 fst_line = max 1 (line1 - pad_before)
2246 line_nos = [ fst_line .. ]
2248 highlighted | do_highlight = zipWith highlight line_nos these_lines
2249 | otherwise = [\p -> BS.concat[p,l] | l <- these_lines]
2251 bs_line_nos = [ BS.pack (show l ++ " ") | l <- line_nos ]
2252 prefixed = zipWith ($) highlighted bs_line_nos
2254 BS.putStrLn (BS.intercalate (BS.pack "\n") prefixed)
2256 file = GHC.srcSpanFile span
2257 line1 = GHC.srcSpanStartLine span
2258 col1 = GHC.srcSpanStartCol span
2259 line2 = GHC.srcSpanEndLine span
2260 col2 = GHC.srcSpanEndCol span
2262 pad_before | line1 == 1 = 0
2266 highlight | do_bold = highlight_bold
2267 | otherwise = highlight_carets
2269 highlight_bold no line prefix
2270 | no == line1 && no == line2
2271 = let (a,r) = BS.splitAt col1 line
2272 (b,c) = BS.splitAt (col2-col1) r
2274 BS.concat [prefix, a,BS.pack start_bold,b,BS.pack end_bold,c]
2276 = let (a,b) = BS.splitAt col1 line in
2277 BS.concat [prefix, a, BS.pack start_bold, b]
2279 = let (a,b) = BS.splitAt col2 line in
2280 BS.concat [prefix, a, BS.pack end_bold, b]
2281 | otherwise = BS.concat [prefix, line]
2283 highlight_carets no line prefix
2284 | no == line1 && no == line2
2285 = BS.concat [prefix, line, nl, indent, BS.replicate col1 ' ',
2286 BS.replicate (col2-col1) '^']
2288 = BS.concat [indent, BS.replicate (col1 - 2) ' ', BS.pack "vv", nl,
2291 = BS.concat [prefix, line, nl, indent, BS.replicate col2 ' ',
2293 | otherwise = BS.concat [prefix, line]
2295 indent = BS.pack (" " ++ replicate (length (show no)) ' ')
2296 nl = BS.singleton '\n'
2298 -- --------------------------------------------------------------------------
2301 getTickArray :: Module -> GHCi TickArray
2302 getTickArray modl = do
2304 let arrmap = tickarrays st
2305 case lookupModuleEnv arrmap modl of
2306 Just arr -> return arr
2308 (_breakArray, ticks) <- getModBreak modl
2309 let arr = mkTickArray (assocs ticks)
2310 setGHCiState st{tickarrays = extendModuleEnv arrmap modl arr}
2313 discardTickArrays :: GHCi ()
2314 discardTickArrays = do
2316 setGHCiState st{tickarrays = emptyModuleEnv}
2318 mkTickArray :: [(BreakIndex,SrcSpan)] -> TickArray
2320 = accumArray (flip (:)) [] (1, max_line)
2321 [ (line, (nm,span)) | (nm,span) <- ticks,
2322 line <- srcSpanLines span ]
2324 max_line = foldr max 0 (map GHC.srcSpanEndLine (map snd ticks))
2325 srcSpanLines span = [ GHC.srcSpanStartLine span ..
2326 GHC.srcSpanEndLine span ]
2328 lookupModule :: String -> GHCi Module
2329 lookupModule modName
2330 = do session <- getSession
2331 io (GHC.findModule session (GHC.mkModuleName modName) Nothing)
2333 -- don't reset the counter back to zero?
2334 discardActiveBreakPoints :: GHCi ()
2335 discardActiveBreakPoints = do
2337 mapM (turnOffBreak.snd) (breaks st)
2338 setGHCiState $ st { breaks = [] }
2340 deleteBreak :: Int -> GHCi ()
2341 deleteBreak identity = do
2343 let oldLocations = breaks st
2344 (this,rest) = partition (\loc -> fst loc == identity) oldLocations
2346 then printForUser (text "Breakpoint" <+> ppr identity <+>
2347 text "does not exist")
2349 mapM (turnOffBreak.snd) this
2350 setGHCiState $ st { breaks = rest }
2352 turnOffBreak :: BreakLocation -> GHCi Bool
2353 turnOffBreak loc = do
2354 (arr, _) <- getModBreak (breakModule loc)
2355 io $ setBreakFlag False arr (breakTick loc)
2357 getModBreak :: Module -> GHCi (GHC.BreakArray, Array Int SrcSpan)
2358 getModBreak mod = do
2359 session <- getSession
2360 Just mod_info <- io $ GHC.getModuleInfo session mod
2361 let modBreaks = GHC.modInfoModBreaks mod_info
2362 let array = GHC.modBreaks_flags modBreaks
2363 let ticks = GHC.modBreaks_locs modBreaks
2364 return (array, ticks)
2366 setBreakFlag :: Bool -> GHC.BreakArray -> Int -> IO Bool
2367 setBreakFlag toggle array index
2368 | toggle = GHC.setBreakOn array index
2369 | otherwise = GHC.setBreakOff array index