1 {-# OPTIONS -fno-cse #-}
2 -- -fno-cse is needed for GLOBAL_VAR's to behave properly
4 {-# OPTIONS -#include "Linker.h" #-}
5 -----------------------------------------------------------------------------
7 -- GHC Interactive User Interface
9 -- (c) The GHC Team 2005-2006
11 -----------------------------------------------------------------------------
13 module InteractiveUI ( interactiveUI, ghciWelcomeMsg ) where
15 #include "HsVersions.h"
17 import qualified GhciMonad
18 import GhciMonad hiding (runStmt)
23 import qualified GHC hiding (resume, runStmt)
24 import GHC ( LoadHowMuch(..), Target(..), TargetId(..),
25 Module, ModuleName, TyThing(..), Phase,
26 BreakIndex, SrcSpan, Resume, SingleStep,
27 Ghc, handleSourceError )
37 import HscTypes ( implicitTyThings, reflectGhc, reifyGhc )
38 import qualified RdrName ( getGRE_NameQualifier_maybes ) -- should this come via GHC?
39 import Outputable hiding (printForUser, printForUserPartWay)
40 import Module -- for ModuleEnv
44 -- Other random utilities
48 import BasicTypes hiding (isTopLevel)
49 import Panic hiding (showException)
55 import Maybes ( orElse, expectJust )
58 import MonadUtils ( liftIO )
60 #ifndef mingw32_HOST_OS
61 import System.Posix hiding (getEnv)
63 import GHC.ConsoleHandler ( flushConsole )
64 import qualified System.Win32
68 import Control.Concurrent ( yield ) -- Used in readline loop
69 import System.Console.Editline.Readline as Readline
75 -- import Control.Concurrent
77 import System.FilePath
78 import qualified Data.ByteString.Char8 as BS
82 import System.Environment
83 import System.Exit ( exitWith, ExitCode(..) )
84 import System.Directory
86 import System.IO.Error as IO
89 import Control.Monad as Monad
93 import GHC.Exts ( unsafeCoerce# )
94 import GHC.IOBase ( IOErrorType(InvalidArgument) )
97 import Data.IORef ( IORef, readIORef, writeIORef )
99 -----------------------------------------------------------------------------
101 ghciWelcomeMsg :: String
102 ghciWelcomeMsg = "GHCi, version " ++ cProjectVersion ++
103 ": http://www.haskell.org/ghc/ :? for help"
105 cmdName :: Command -> String
106 cmdName (n,_,_,_) = n
108 GLOBAL_VAR(macros_ref, [], [Command])
110 builtin_commands :: [Command]
112 -- Hugs users are accustomed to :e, so make sure it doesn't overlap
113 ("?", keepGoing help, Nothing, completeNone),
114 ("add", keepGoingPaths addModule, Just filenameWordBreakChars, completeFilename),
115 ("abandon", keepGoing abandonCmd, Nothing, completeNone),
116 ("break", keepGoing breakCmd, Nothing, completeIdentifier),
117 ("back", keepGoing backCmd, Nothing, completeNone),
118 ("browse", keepGoing (browseCmd False), Nothing, completeModule),
119 ("browse!", keepGoing (browseCmd True), Nothing, completeModule),
120 ("cd", keepGoing changeDirectory, Just filenameWordBreakChars, completeFilename),
121 ("check", keepGoing checkModule, Nothing, completeHomeModule),
122 ("continue", keepGoing continueCmd, Nothing, completeNone),
123 ("cmd", keepGoing cmdCmd, Nothing, completeIdentifier),
124 ("ctags", keepGoing createCTagsFileCmd, Just filenameWordBreakChars, completeFilename),
125 ("def", keepGoing (defineMacro False), Nothing, completeIdentifier),
126 ("def!", keepGoing (defineMacro True), Nothing, completeIdentifier),
127 ("delete", keepGoing deleteCmd, Nothing, completeNone),
128 ("e", keepGoing editFile, Just filenameWordBreakChars, completeFilename),
129 ("edit", keepGoing editFile, Just filenameWordBreakChars, completeFilename),
130 ("etags", keepGoing createETagsFileCmd, Just filenameWordBreakChars, completeFilename),
131 ("force", keepGoing forceCmd, Nothing, completeIdentifier),
132 ("forward", keepGoing forwardCmd, Nothing, completeNone),
133 ("help", keepGoing help, Nothing, completeNone),
134 ("history", keepGoing historyCmd, Nothing, completeNone),
135 ("info", keepGoing info, Nothing, completeIdentifier),
136 ("kind", keepGoing kindOfType, Nothing, completeIdentifier),
137 ("load", keepGoingPaths loadModule_, Just filenameWordBreakChars, completeHomeModuleOrFile),
138 ("list", keepGoing listCmd, Nothing, completeNone),
139 ("module", keepGoing setContext, Nothing, completeModule),
140 ("main", keepGoing runMain, Nothing, completeIdentifier),
141 ("print", keepGoing printCmd, Nothing, completeIdentifier),
142 ("quit", quit, Nothing, completeNone),
143 ("reload", keepGoing reloadModule, Nothing, completeNone),
144 ("run", keepGoing runRun, Nothing, completeIdentifier),
145 ("set", keepGoing setCmd, Just flagWordBreakChars, completeSetOptions),
146 ("show", keepGoing showCmd, Nothing, completeNone),
147 ("sprint", keepGoing sprintCmd, Nothing, completeIdentifier),
148 ("step", keepGoing stepCmd, Nothing, completeIdentifier),
149 ("steplocal", keepGoing stepLocalCmd, Nothing, completeIdentifier),
150 ("stepmodule",keepGoing stepModuleCmd, Nothing, completeIdentifier),
151 ("type", keepGoing typeOfExpr, Nothing, completeIdentifier),
152 ("trace", keepGoing traceCmd, Nothing, completeIdentifier),
153 ("undef", keepGoing undefineMacro, Nothing, completeMacro),
154 ("unset", keepGoing unsetOptions, Just flagWordBreakChars, completeSetOptions)
158 -- We initialize readline (in the interactiveUI function) to use
159 -- word_break_chars as the default set of completion word break characters.
160 -- This can be overridden for a particular command (for example, filename
161 -- expansion shouldn't consider '/' to be a word break) by setting the third
162 -- entry in the Command tuple above.
164 -- NOTE: in order for us to override the default correctly, any custom entry
165 -- must be a SUBSET of word_break_chars.
167 word_break_chars :: String
168 word_break_chars = let symbols = "!#$%&*+/<=>?@\\^|-~"
169 specials = "(),;[]`{}"
171 in spaces ++ specials ++ symbols
174 flagWordBreakChars, filenameWordBreakChars :: String
175 flagWordBreakChars = " \t\n"
176 filenameWordBreakChars = " \t\n\\`@$><=;|&{(" -- bash defaults
179 keepGoing :: (String -> GHCi ()) -> (String -> GHCi Bool)
180 keepGoing a str = a str >> return False
182 keepGoingPaths :: ([FilePath] -> GHCi ()) -> (String -> GHCi Bool)
184 = do case toArgs str of
185 Left err -> io (hPutStrLn stderr err)
189 shortHelpText :: String
190 shortHelpText = "use :? for help.\n"
194 " Commands available from the prompt:\n" ++
196 " <statement> evaluate/run <statement>\n" ++
197 " : repeat last command\n" ++
198 " :{\\n ..lines.. \\n:}\\n multiline command\n" ++
199 " :add [*]<module> ... add module(s) to the current target set\n" ++
200 " :browse[!] [[*]<mod>] display the names defined by module <mod>\n" ++
201 " (!: more details; *: all top-level names)\n" ++
202 " :cd <dir> change directory to <dir>\n" ++
203 " :cmd <expr> run the commands returned by <expr>::IO String\n" ++
204 " :ctags [<file>] create tags file for Vi (default: \"tags\")\n" ++
205 " :def <cmd> <expr> define a command :<cmd>\n" ++
206 " :edit <file> edit file\n" ++
207 " :edit edit last module\n" ++
208 " :etags [<file>] create tags file for Emacs (default: \"TAGS\")\n" ++
209 " :help, :? display this list of commands\n" ++
210 " :info [<name> ...] display information about the given names\n" ++
211 " :kind <type> show the kind of <type>\n" ++
212 " :load [*]<module> ... load module(s) and their dependents\n" ++
213 " :main [<arguments> ...] run the main function with the given arguments\n" ++
214 " :module [+/-] [*]<mod> ... set the context for expression evaluation\n" ++
215 " :quit exit GHCi\n" ++
216 " :reload reload the current module set\n" ++
217 " :run function [<arguments> ...] run the function with the given arguments\n" ++
218 " :type <expr> show the type of <expr>\n" ++
219 " :undef <cmd> undefine user-defined command :<cmd>\n" ++
220 " :!<command> run the shell command <command>\n" ++
222 " -- Commands for debugging:\n" ++
224 " :abandon at a breakpoint, abandon current computation\n" ++
225 " :back go back in the history (after :trace)\n" ++
226 " :break [<mod>] <l> [<col>] set a breakpoint at the specified location\n" ++
227 " :break <name> set a breakpoint on the specified function\n" ++
228 " :continue resume after a breakpoint\n" ++
229 " :delete <number> delete the specified breakpoint\n" ++
230 " :delete * delete all breakpoints\n" ++
231 " :force <expr> print <expr>, forcing unevaluated parts\n" ++
232 " :forward go forward in the history (after :back)\n" ++
233 " :history [<n>] after :trace, show the execution history\n" ++
234 " :list show the source code around current breakpoint\n" ++
235 " :list identifier show the source code for <identifier>\n" ++
236 " :list [<module>] <line> show the source code around line number <line>\n" ++
237 " :print [<name> ...] prints a value without forcing its computation\n" ++
238 " :sprint [<name> ...] simplifed version of :print\n" ++
239 " :step single-step after stopping at a breakpoint\n"++
240 " :step <expr> single-step into <expr>\n"++
241 " :steplocal single-step within the current top-level binding\n"++
242 " :stepmodule single-step restricted to the current module\n"++
243 " :trace trace after stopping at a breakpoint\n"++
244 " :trace <expr> evaluate <expr> with tracing on (see :history)\n"++
247 " -- Commands for changing settings:\n" ++
249 " :set <option> ... set options\n" ++
250 " :set args <arg> ... set the arguments returned by System.getArgs\n" ++
251 " :set prog <progname> set the value returned by System.getProgName\n" ++
252 " :set prompt <prompt> set the prompt used in GHCi\n" ++
253 " :set editor <cmd> set the command used for :edit\n" ++
254 " :set stop [<n>] <cmd> set the command to run when a breakpoint is hit\n" ++
255 " :unset <option> ... unset options\n" ++
257 " Options for ':set' and ':unset':\n" ++
259 " +r revert top-level expressions after each evaluation\n" ++
260 " +s print timing/memory stats after each evaluation\n" ++
261 " +t print type after evaluation\n" ++
262 " -<flags> most GHC command line flags can also be set here\n" ++
263 " (eg. -v2, -fglasgow-exts, etc.)\n" ++
264 " for GHCi-specific flags, see User's Guide,\n"++
265 " Flag reference, Interactive-mode options\n" ++
267 " -- Commands for displaying information:\n" ++
269 " :show bindings show the current bindings made at the prompt\n" ++
270 " :show breaks show the active breakpoints\n" ++
271 " :show context show the breakpoint context\n" ++
272 " :show modules show the currently loaded modules\n" ++
273 " :show packages show the currently active package flags\n" ++
274 " :show languages show the currently active language flags\n" ++
275 " :show <setting> show value of <setting>, which is one of\n" ++
276 " [args, prog, prompt, editor, stop]\n" ++
279 findEditor :: IO String
284 win <- System.Win32.getWindowsDirectory
285 return (win </> "notepad.exe")
290 interactiveUI :: [(FilePath, Maybe Phase)] -> Maybe [String]
292 interactiveUI srcs maybe_exprs = withTerminalReset $ do
293 -- HACK! If we happen to get into an infinite loop (eg the user
294 -- types 'let x=x in x' at the prompt), then the thread will block
295 -- on a blackhole, and become unreachable during GC. The GC will
296 -- detect that it is unreachable and send it the NonTermination
297 -- exception. However, since the thread is unreachable, everything
298 -- it refers to might be finalized, including the standard Handles.
299 -- This sounds like a bug, but we don't have a good solution right
301 liftIO $ newStablePtr stdin
302 liftIO $ newStablePtr stdout
303 liftIO $ newStablePtr stderr
305 -- Initialise buffering for the *interpreted* I/O system
308 liftIO $ when (isNothing maybe_exprs) $ do
309 -- Only for GHCi (not runghc and ghc -e):
311 -- Turn buffering off for the compiled program's stdout/stderr
313 -- Turn buffering off for GHCi's stdout
315 hSetBuffering stdout NoBuffering
316 -- We don't want the cmd line to buffer any input that might be
317 -- intended for the program, so unbuffer stdin.
318 hSetBuffering stdin NoBuffering
321 is_tty <- hIsTerminalDevice stdin
322 when is_tty $ withReadline $ do
326 (\dir -> Readline.readHistory (dir </> "ghci_history"))
329 Readline.setAttemptedCompletionFunction (Just completeWord)
330 --Readline.parseAndBind "set show-all-if-ambiguous 1"
332 Readline.setBasicWordBreakCharacters word_break_chars
333 Readline.setCompleterWordBreakCharacters word_break_chars
334 Readline.setCompletionAppendCharacter Nothing
337 -- initial context is just the Prelude
338 prel_mod <- GHC.findModule (GHC.mkModuleName "Prelude") Nothing
339 GHC.setContext [] [prel_mod]
341 default_editor <- liftIO $ findEditor
343 cwd <- liftIO $ getCurrentDirectory
345 startGHCi (runGHCi srcs maybe_exprs)
346 GHCiState{ progname = "<interactive>",
350 editor = default_editor,
351 -- session = session,
356 tickarrays = emptyModuleEnv,
357 last_command = Nothing,
361 ghc_e = isJust maybe_exprs
366 Readline.stifleHistory 100
367 withGhcAppData (\dir -> Readline.writeHistory (dir </> "ghci_history"))
369 Readline.resetTerminal Nothing
374 withGhcAppData :: (FilePath -> IO a) -> IO a -> IO a
375 withGhcAppData right left = do
376 either_dir <- IO.try (getAppUserDataDirectory "ghc")
378 Right dir -> right dir
381 -- libedit doesn't always restore the terminal settings correctly (as of at
382 -- least 07/12/2008); see trac #2691. Work around this by manually resetting
383 -- the terminal outselves.
384 withTerminalReset :: Ghc () -> Ghc ()
385 #ifdef mingw32_HOST_OS
386 withTerminalReset = id
388 withTerminalReset f = do
389 isTTY <- liftIO $ hIsTerminalDevice stdout
392 else gbracket (liftIO $ getTerminalAttributes stdOutput)
393 (\attrs -> liftIO $ setTerminalAttributes stdOutput attrs Immediately)
397 runGHCi :: [(FilePath, Maybe Phase)] -> Maybe [String] -> GHCi ()
398 runGHCi paths maybe_exprs = do
400 read_dot_files = not opt_IgnoreDotGhci
402 current_dir = return (Just ".ghci")
404 app_user_dir = io $ withGhcAppData
405 (\dir -> return (Just (dir </> "ghci.conf")))
409 either_dir <- io $ IO.try (getEnv "HOME")
411 Right home -> return (Just (home </> ".ghci"))
414 sourceConfigFile :: FilePath -> GHCi ()
415 sourceConfigFile file = do
416 exists <- io $ doesFileExist file
418 dir_ok <- io $ checkPerms (getDirectory file)
419 file_ok <- io $ checkPerms file
420 when (dir_ok && file_ok) $ do
421 either_hdl <- io $ IO.try (openFile file ReadMode)
424 Right hdl -> runCommands (fileLoop hdl False False)
426 getDirectory f = case takeDirectory f of "" -> "."; d -> d
428 when (read_dot_files) $ do
429 cfgs0 <- sequence [ current_dir, app_user_dir, home_dir ]
430 cfgs <- io $ mapM canonicalizePath (catMaybes cfgs0)
431 mapM_ sourceConfigFile (nub cfgs)
432 -- nub, because we don't want to read .ghci twice if the
435 -- Perform a :load for files given on the GHCi command line
436 -- When in -e mode, if the load fails then we want to stop
437 -- immediately rather than going on to evaluate the expression.
438 when (not (null paths)) $ do
439 ok <- ghciHandle (\e -> do showException e; return Failed) $
441 when (isJust maybe_exprs && failed ok) $
442 io (exitWith (ExitFailure 1))
444 -- if verbosity is greater than 0, or we are connected to a
445 -- terminal, display the prompt in the interactive loop.
446 is_tty <- io (hIsTerminalDevice stdin)
447 dflags <- getDynFlags
448 let show_prompt = verbosity dflags > 0 || is_tty
453 #if defined(mingw32_HOST_OS)
454 -- The win32 Console API mutates the first character of
455 -- type-ahead when reading from it in a non-buffered manner. Work
456 -- around this by flushing the input buffer of type-ahead characters,
457 -- but only if stdin is available.
458 flushed <- io (IO.try (GHC.ConsoleHandler.flushConsole stdin))
460 Left err | isDoesNotExistError err -> return ()
461 | otherwise -> io (ioError err)
462 Right () -> return ()
464 -- enter the interactive loop
465 interactiveLoop is_tty show_prompt
467 -- just evaluate the expression we were given
468 enqueueCommands exprs
469 let handle e = do st <- getGHCiState
470 -- Jump through some hoops to get the
471 -- current progname in the exception text:
472 -- <progname>: <exception>
473 io $ withProgName (progname st)
474 -- this used to be topHandlerFastExit, see #2228
476 runCommands' handle (return Nothing)
479 io $ do when (verbosity dflags > 0) $ putStrLn "Leaving GHCi."
481 interactiveLoop :: Bool -> Bool -> GHCi ()
482 interactiveLoop is_tty show_prompt =
483 -- Ignore ^C exceptions caught here
484 ghciHandleGhcException (\e -> case e of
486 #if defined(mingw32_HOST_OS)
489 interactiveLoop is_tty show_prompt
490 _other -> return ()) $
492 ghciUnblock $ do -- unblock necessary if we recursed from the
493 -- exception handler above.
495 -- read commands from stdin
498 then runCommands readlineLoop
499 else runCommands (fileLoop stdin show_prompt is_tty)
501 runCommands (fileLoop stdin show_prompt is_tty)
505 -- NOTE: We only read .ghci files if they are owned by the current user,
506 -- and aren't world writable. Otherwise, we could be accidentally
507 -- running code planted by a malicious third party.
509 -- Furthermore, We only read ./.ghci if . is owned by the current user
510 -- and isn't writable by anyone else. I think this is sufficient: we
511 -- don't need to check .. and ../.. etc. because "." always refers to
512 -- the same directory while a process is running.
514 checkPerms :: String -> IO Bool
515 #ifdef mingw32_HOST_OS
520 handleIO (\_ -> return False) $ do
521 st <- getFileStatus name
523 if fileOwner st /= me then do
524 putStrLn $ "WARNING: " ++ name ++ " is owned by someone else, IGNORING!"
527 let mode = fileMode st
528 if (groupWriteMode == (mode `intersectFileModes` groupWriteMode))
529 || (otherWriteMode == (mode `intersectFileModes` otherWriteMode))
531 putStrLn $ "*** WARNING: " ++ name ++
532 " is writable by someone else, IGNORING!"
537 fileLoop :: Handle -> Bool -> Bool -> GHCi (Maybe String)
538 fileLoop hdl show_prompt is_tty = do
539 when show_prompt $ do
542 l <- io (IO.try (hGetLine hdl))
544 Left e | isEOFError e -> return Nothing
545 | InvalidArgument <- etype -> return Nothing
546 | otherwise -> io (ioError e)
547 where etype = ioeGetErrorType e
548 -- treat InvalidArgument in the same way as EOF:
549 -- this can happen if the user closed stdin, or
550 -- perhaps did getContents which closes stdin at
553 str <- io $ consoleInputToUnicode is_tty l
556 #ifdef mingw32_HOST_OS
557 -- Convert the console input into Unicode according to the current code page.
558 -- The Windows console stores Unicode characters directly, so this is a
559 -- rather roundabout way of doing things... oh well.
560 -- See #782, #1483, #1649
561 consoleInputToUnicode :: Bool -> String -> IO String
562 consoleInputToUnicode is_tty str
564 cp <- System.Win32.getConsoleCP
565 System.Win32.stringToUnicode cp str
567 decodeStringAsUTF8 str
569 -- for Unix, assume the input is in UTF-8 and decode it to a Unicode String.
571 consoleInputToUnicode :: Bool -> String -> IO String
572 consoleInputToUnicode _is_tty str = decodeStringAsUTF8 str
575 decodeStringAsUTF8 :: String -> IO String
576 decodeStringAsUTF8 str =
577 withCStringLen str $ \(cstr,len) ->
578 utf8DecodeString (castPtr cstr :: Ptr Word8) len
580 mkPrompt :: GHCi String
582 (toplevs,exports) <- GHC.getContext
583 resumes <- GHC.getResumeContext
584 -- st <- getGHCiState
590 let ix = GHC.resumeHistoryIx r
592 then return (brackets (ppr (GHC.resumeSpan r)) <> space)
594 let hist = GHC.resumeHistory r !! (ix-1)
595 span <- GHC.getHistorySpan hist
596 return (brackets (ppr (negate ix) <> char ':'
597 <+> ppr span) <> space)
599 dots | _:rs <- resumes, not (null rs) = text "... "
606 -- let (btoplevs, bexports) = fromMaybe ([],[]) (remembered_ctx st) in
607 -- hsep (map (\m -> text "!*" <> ppr (GHC.moduleName m)) btoplevs) <+>
608 -- hsep (map (\m -> char '!' <> ppr (GHC.moduleName m)) bexports) <+>
609 hsep (map (\m -> char '*' <> ppr (GHC.moduleName m)) toplevs) <+>
610 hsep (map (ppr . GHC.moduleName) exports)
612 deflt_prompt = dots <> context_bit <> modules_bit
614 f ('%':'s':xs) = deflt_prompt <> f xs
615 f ('%':'%':xs) = char '%' <> f xs
616 f (x:xs) = char x <> f xs
620 return (showSDoc (f (prompt st)))
624 readlineLoop :: GHCi (Maybe String)
627 saveSession -- for use by completion
629 l <- io $ withReadline (readline prompt)
632 Nothing -> return Nothing
633 Just "" -> return (Just "") -- Don't put empty lines in the history
636 str <- io $ consoleInputToUnicode True l
639 withReadline :: IO a -> IO a
640 withReadline = bracket_ stopTimer startTimer
641 -- editline doesn't handle some of its system calls returning
642 -- EINTR, so our timer signal confuses it, hence we turn off
643 -- the timer signal when making calls to editline. (#2277)
644 -- If editline is ever fixed, we can remove this.
646 -- These come from the RTS
647 foreign import ccall unsafe startTimer :: IO ()
648 foreign import ccall unsafe stopTimer :: IO ()
651 queryQueue :: GHCi (Maybe String)
656 c:cs -> do setGHCiState st{ cmdqueue = cs }
659 runCommands :: GHCi (Maybe String) -> GHCi ()
660 runCommands = runCommands' handler
662 runCommands' :: (SomeException -> GHCi Bool) -- Exception handler
663 -> GHCi (Maybe String) -> GHCi ()
664 runCommands' eh getCmd = do
665 mb_cmd <- noSpace queryQueue
666 mb_cmd <- maybe (noSpace getCmd) (return . Just) mb_cmd
671 handleSourceError printErrorAndKeepGoing
673 if b then return () else runCommands' eh getCmd
675 printErrorAndKeepGoing err = do
676 GHC.printExceptionAndWarnings err
679 noSpace q = q >>= maybe (return Nothing)
680 (\c->case removeSpaces c of
682 ":{" -> multiLineCmd q
683 c -> return (Just c) )
687 setGHCiState st{ prompt = "%s| " }
688 mb_cmd <- collectCommand q ""
689 getGHCiState >>= \st->setGHCiState st{ prompt = p }
691 -- we can't use removeSpaces for the sublines here, so
692 -- multiline commands are somewhat more brittle against
693 -- fileformat errors (such as \r in dos input on unix),
694 -- we get rid of any extra spaces for the ":}" test;
695 -- we also avoid silent failure if ":}" is not found;
696 -- and since there is no (?) valid occurrence of \r (as
697 -- opposed to its String representation, "\r") inside a
698 -- ghci command, we replace any such with ' ' (argh:-(
699 collectCommand q c = q >>=
700 maybe (io (ioError collectError))
701 (\l->if removeSpaces l == ":}"
702 then return (Just $ removeSpaces c)
703 else collectCommand q (c++map normSpace l))
704 where normSpace '\r' = ' '
706 -- QUESTION: is userError the one to use here?
707 collectError = userError "unterminated multiline command :{ .. :}"
708 doCommand (':' : cmd) = specialCommand cmd
709 doCommand stmt = do timeIt $ runStmt stmt GHC.RunToCompletion
712 enqueueCommands :: [String] -> GHCi ()
713 enqueueCommands cmds = do
715 setGHCiState st{ cmdqueue = cmds ++ cmdqueue st }
718 runStmt :: String -> SingleStep -> GHCi Bool
720 | null (filter (not.isSpace) stmt) = return False
721 | ["import", mod] <- words stmt = keepGoing setContext ('+':mod)
723 = do result <- GhciMonad.runStmt stmt step
724 afterRunStmt (const True) result
726 --afterRunStmt :: GHC.RunResult -> GHCi Bool
727 -- False <=> the statement failed to compile
728 afterRunStmt :: (SrcSpan -> Bool) -> GHC.RunResult -> GHCi Bool
729 afterRunStmt _ (GHC.RunException e) = throw e
730 afterRunStmt step_here run_result = do
731 resumes <- GHC.getResumeContext
733 GHC.RunOk names -> do
734 show_types <- isOptionSet ShowType
735 when show_types $ printTypeOfNames names
736 GHC.RunBreak _ names mb_info
737 | isNothing mb_info ||
738 step_here (GHC.resumeSpan $ head resumes) -> do
739 printForUser $ ptext (sLit "Stopped at") <+>
740 ppr (GHC.resumeSpan $ head resumes)
741 -- printTypeOfNames session names
742 let namesSorted = sortBy compareNames names
743 tythings <- catMaybes `liftM`
744 mapM GHC.lookupName namesSorted
745 docs <- pprTypeAndContents [id | AnId id <- tythings]
746 printForUserPartWay docs
747 maybe (return ()) runBreakCmd mb_info
748 -- run the command set with ":set stop <cmd>"
750 enqueueCommands [stop st]
752 | otherwise -> resume GHC.SingleStep >>=
753 afterRunStmt step_here >> return ()
757 io installSignalHandlers
758 b <- isOptionSet RevertCAFs
761 return (case run_result of GHC.RunOk _ -> True; _ -> False)
763 runBreakCmd :: GHC.BreakInfo -> GHCi ()
764 runBreakCmd info = do
765 let mod = GHC.breakInfo_module info
766 nm = GHC.breakInfo_number info
768 case [ loc | (_,loc) <- breaks st,
769 breakModule loc == mod, breakTick loc == nm ] of
771 loc:_ | null cmd -> return ()
772 | otherwise -> do enqueueCommands [cmd]; return ()
773 where cmd = onBreakCmd loc
775 printTypeOfNames :: [Name] -> GHCi ()
776 printTypeOfNames names
777 = mapM_ (printTypeOfName ) $ sortBy compareNames names
779 compareNames :: Name -> Name -> Ordering
780 n1 `compareNames` n2 = compareWith n1 `compare` compareWith n2
781 where compareWith n = (getOccString n, getSrcSpan n)
783 printTypeOfName :: Name -> GHCi ()
785 = do maybe_tything <- GHC.lookupName n
786 case maybe_tything of
788 Just thing -> printTyThing thing
791 data MaybeCommand = GotCommand Command | BadCommand | NoLastCommand
793 specialCommand :: String -> GHCi Bool
794 specialCommand ('!':str) = shellEscape (dropWhile isSpace str)
795 specialCommand str = do
796 let (cmd,rest) = break isSpace str
797 maybe_cmd <- lookupCommand cmd
799 GotCommand (_,f,_,_) -> f (dropWhile isSpace rest)
801 do io $ hPutStr stdout ("unknown command ':" ++ cmd ++ "'\n"
805 do io $ hPutStr stdout ("there is no last command to perform\n"
809 lookupCommand :: String -> GHCi (MaybeCommand)
810 lookupCommand "" = do
812 case last_command st of
813 Just c -> return $ GotCommand c
814 Nothing -> return NoLastCommand
815 lookupCommand str = do
816 mc <- io $ lookupCommand' str
818 setGHCiState st{ last_command = mc }
820 Just c -> GotCommand c
821 Nothing -> BadCommand
823 lookupCommand' :: String -> IO (Maybe Command)
824 lookupCommand' str = do
825 macros <- readIORef macros_ref
826 let cmds = builtin_commands ++ macros
827 -- look for exact match first, then the first prefix match
828 return $ case [ c | c <- cmds, str == cmdName c ] of
830 [] -> case [ c | c@(s,_,_,_) <- cmds, str `isPrefixOf` s ] of
834 getCurrentBreakSpan :: GHCi (Maybe SrcSpan)
835 getCurrentBreakSpan = do
836 resumes <- GHC.getResumeContext
840 let ix = GHC.resumeHistoryIx r
842 then return (Just (GHC.resumeSpan r))
844 let hist = GHC.resumeHistory r !! (ix-1)
845 span <- GHC.getHistorySpan hist
848 getCurrentBreakModule :: GHCi (Maybe Module)
849 getCurrentBreakModule = do
850 resumes <- GHC.getResumeContext
854 let ix = GHC.resumeHistoryIx r
856 then return (GHC.breakInfo_module `liftM` GHC.resumeBreakInfo r)
858 let hist = GHC.resumeHistory r !! (ix-1)
859 return $ Just $ GHC.getHistoryModule hist
861 -----------------------------------------------------------------------------
864 noArgs :: GHCi () -> String -> GHCi ()
866 noArgs _ _ = io $ putStrLn "This command takes no arguments"
868 help :: String -> GHCi ()
869 help _ = io (putStr helpText)
871 info :: String -> GHCi ()
872 info "" = ghcError (CmdLineError "syntax: ':i <thing-you-want-info-about>'")
873 info s = handleSourceError GHC.printExceptionAndWarnings $ do
874 { let names = words s
875 ; dflags <- getDynFlags
876 ; let pefas = dopt Opt_PrintExplicitForalls dflags
877 ; mapM_ (infoThing pefas) names }
879 infoThing pefas str = do
880 names <- GHC.parseName str
881 mb_stuffs <- mapM GHC.getInfo names
882 let filtered = filterOutChildren (\(t,_f,_i) -> t) (catMaybes mb_stuffs)
883 unqual <- GHC.getPrintUnqual
885 putStrLn (showSDocForUser unqual $
886 vcat (intersperse (text "") $
887 map (pprInfo pefas) filtered))
889 -- Filter out names whose parent is also there Good
890 -- example is '[]', which is both a type and data
891 -- constructor in the same type
892 filterOutChildren :: (a -> TyThing) -> [a] -> [a]
893 filterOutChildren get_thing xs
894 = [x | x <- xs, not (getName (get_thing x) `elemNameSet` implicits)]
896 implicits = mkNameSet [getName t | x <- xs, t <- implicitTyThings (get_thing x)]
898 pprInfo :: PrintExplicitForalls -> (TyThing, Fixity, [GHC.Instance]) -> SDoc
899 pprInfo pefas (thing, fixity, insts)
900 = pprTyThingInContextLoc pefas thing
901 $$ show_fixity fixity
902 $$ vcat (map GHC.pprInstance insts)
905 | fix == GHC.defaultFixity = empty
906 | otherwise = ppr fix <+> ppr (GHC.getName thing)
908 runMain :: String -> GHCi ()
909 runMain s = case toArgs s of
910 Left err -> io (hPutStrLn stderr err)
912 do dflags <- getDynFlags
913 case mainFunIs dflags of
914 Nothing -> doWithArgs args "main"
915 Just f -> doWithArgs args f
917 runRun :: String -> GHCi ()
918 runRun s = case toCmdArgs s of
919 Left err -> io (hPutStrLn stderr err)
920 Right (cmd, args) -> doWithArgs args cmd
922 doWithArgs :: [String] -> String -> GHCi ()
923 doWithArgs args cmd = enqueueCommands ["System.Environment.withArgs " ++
924 show args ++ " (" ++ cmd ++ ")"]
926 addModule :: [FilePath] -> GHCi ()
928 revertCAFs -- always revert CAFs on load/add.
929 files <- mapM expandPath files
930 targets <- mapM (\m -> GHC.guessTarget m Nothing) files
931 -- remove old targets with the same id; e.g. for :add *M
932 mapM_ GHC.removeTarget [ tid | Target tid _ _ <- targets ]
933 mapM_ GHC.addTarget targets
934 prev_context <- GHC.getContext
935 ok <- trySuccess $ GHC.load LoadAllTargets
936 afterLoad ok False prev_context
938 changeDirectory :: String -> GHCi ()
939 changeDirectory "" = do
940 -- :cd on its own changes to the user's home directory
941 either_dir <- io (IO.try getHomeDirectory)
944 Right dir -> changeDirectory dir
945 changeDirectory dir = do
946 graph <- GHC.getModuleGraph
947 when (not (null graph)) $
948 io $ putStr "Warning: changing directory causes all loaded modules to be unloaded,\nbecause the search path has changed.\n"
949 prev_context <- GHC.getContext
951 GHC.load LoadAllTargets
952 setContextAfterLoad prev_context False []
953 GHC.workingDirectoryChanged
954 dir <- expandPath dir
955 io (setCurrentDirectory dir)
957 trySuccess :: GHC.GhcMonad m => m SuccessFlag -> m SuccessFlag
959 handleSourceError (\e -> do GHC.printExceptionAndWarnings e
963 editFile :: String -> GHCi ()
965 do file <- if null str then chooseEditFile else return str
969 $ ghcError (CmdLineError "editor not set, use :set editor")
970 io $ system (cmd ++ ' ':file)
973 -- The user didn't specify a file so we pick one for them.
974 -- Our strategy is to pick the first module that failed to load,
975 -- or otherwise the first target.
977 -- XXX: Can we figure out what happened if the depndecy analysis fails
978 -- (e.g., because the porgrammeer mistyped the name of a module)?
979 -- XXX: Can we figure out the location of an error to pass to the editor?
980 -- XXX: if we could figure out the list of errors that occured during the
981 -- last load/reaload, then we could start the editor focused on the first
983 chooseEditFile :: GHCi String
985 do let hasFailed x = fmap not $ GHC.isLoaded $ GHC.ms_mod_name x
987 graph <- GHC.getModuleGraph
988 failed_graph <- filterM hasFailed graph
989 let order g = flattenSCCs $ GHC.topSortModuleGraph True g Nothing
991 x : _ -> GHC.ml_hs_file (GHC.ms_location x)
994 case pick (order failed_graph) of
995 Just file -> return file
997 do targets <- GHC.getTargets
998 case msum (map fromTarget targets) of
999 Just file -> return file
1000 Nothing -> ghcError (CmdLineError "No files to edit.")
1002 where fromTarget (GHC.Target (GHC.TargetFile f _) _ _) = Just f
1003 fromTarget _ = Nothing -- when would we get a module target?
1005 defineMacro :: Bool{-overwrite-} -> String -> GHCi ()
1006 defineMacro overwrite s = do
1007 let (macro_name, definition) = break isSpace s
1008 macros <- io (readIORef macros_ref)
1009 let defined = map cmdName macros
1010 if (null macro_name)
1011 then if null defined
1012 then io $ putStrLn "no macros defined"
1013 else io $ putStr ("the following macros are defined:\n" ++
1016 if (not overwrite && macro_name `elem` defined)
1017 then ghcError (CmdLineError
1018 ("macro '" ++ macro_name ++ "' is already defined"))
1021 let filtered = [ cmd | cmd <- macros, cmdName cmd /= macro_name ]
1023 -- give the expression a type signature, so we can be sure we're getting
1024 -- something of the right type.
1025 let new_expr = '(' : definition ++ ") :: String -> IO String"
1027 -- compile the expression
1028 handleSourceError (\e -> GHC.printExceptionAndWarnings e) $ do
1029 hv <- GHC.compileExpr new_expr
1030 io (writeIORef macros_ref --
1031 (filtered ++ [(macro_name, runMacro hv, Nothing, completeNone)]))
1033 runMacro :: GHC.HValue{-String -> IO String-} -> String -> GHCi Bool
1035 str <- io ((unsafeCoerce# fun :: String -> IO String) s)
1036 enqueueCommands (lines str)
1039 undefineMacro :: String -> GHCi ()
1040 undefineMacro str = mapM_ undef (words str)
1041 where undef macro_name = do
1042 cmds <- io (readIORef macros_ref)
1043 if (macro_name `notElem` map cmdName cmds)
1044 then ghcError (CmdLineError
1045 ("macro '" ++ macro_name ++ "' is not defined"))
1047 io (writeIORef macros_ref (filter ((/= macro_name) . cmdName) cmds))
1049 cmdCmd :: String -> GHCi ()
1051 let expr = '(' : str ++ ") :: IO String"
1052 handleSourceError (\e -> GHC.printExceptionAndWarnings e) $ do
1053 hv <- GHC.compileExpr expr
1054 cmds <- io $ (unsafeCoerce# hv :: IO String)
1055 enqueueCommands (lines cmds)
1058 loadModule :: [(FilePath, Maybe Phase)] -> GHCi SuccessFlag
1059 loadModule fs = timeIt (loadModule' fs)
1061 loadModule_ :: [FilePath] -> GHCi ()
1062 loadModule_ fs = do loadModule (zip fs (repeat Nothing)); return ()
1064 loadModule' :: [(FilePath, Maybe Phase)] -> GHCi SuccessFlag
1065 loadModule' files = do
1066 prev_context <- GHC.getContext
1070 discardActiveBreakPoints
1072 GHC.load LoadAllTargets
1075 let (filenames, phases) = unzip files
1076 exp_filenames <- mapM expandPath filenames
1077 let files' = zip exp_filenames phases
1078 targets <- mapM (uncurry GHC.guessTarget) files'
1080 -- NOTE: we used to do the dependency anal first, so that if it
1081 -- fails we didn't throw away the current set of modules. This would
1082 -- require some re-working of the GHC interface, so we'll leave it
1083 -- as a ToDo for now.
1085 GHC.setTargets targets
1086 doLoad False prev_context LoadAllTargets
1088 checkModule :: String -> GHCi ()
1090 let modl = GHC.mkModuleName m
1091 prev_context <- GHC.getContext
1092 ok <- handleSourceError (\e -> GHC.printExceptionAndWarnings e >> return False) $ do
1093 r <- GHC.typecheckModule =<< GHC.parseModule =<< GHC.getModSummary modl
1094 io $ putStrLn (showSDoc (
1095 case GHC.moduleInfo r of
1096 cm | Just scope <- GHC.modInfoTopLevelScope cm ->
1098 (local,global) = ASSERT( all isExternalName scope )
1099 partition ((== modl) . GHC.moduleName . GHC.nameModule) scope
1101 (text "global names: " <+> ppr global) $$
1102 (text "local names: " <+> ppr local)
1105 afterLoad (successIf ok) False prev_context
1107 reloadModule :: String -> GHCi ()
1109 prev_context <- GHC.getContext
1110 doLoad True prev_context $
1111 if null m then LoadAllTargets
1112 else LoadUpTo (GHC.mkModuleName m)
1115 doLoad :: Bool -> ([Module],[Module]) -> LoadHowMuch -> GHCi SuccessFlag
1116 doLoad retain_context prev_context howmuch = do
1117 -- turn off breakpoints before we load: we can't turn them off later, because
1118 -- the ModBreaks will have gone away.
1119 discardActiveBreakPoints
1120 ok <- trySuccess $ GHC.load howmuch
1121 afterLoad ok retain_context prev_context
1124 afterLoad :: SuccessFlag -> Bool -> ([Module],[Module]) -> GHCi ()
1125 afterLoad ok retain_context prev_context = do
1126 revertCAFs -- always revert CAFs on load.
1128 loaded_mod_summaries <- getLoadedModules
1129 let loaded_mods = map GHC.ms_mod loaded_mod_summaries
1130 loaded_mod_names = map GHC.moduleName loaded_mods
1131 modulesLoadedMsg ok loaded_mod_names
1133 setContextAfterLoad prev_context retain_context loaded_mod_summaries
1136 setContextAfterLoad :: ([Module],[Module]) -> Bool -> [GHC.ModSummary] -> GHCi ()
1137 setContextAfterLoad prev keep_ctxt [] = do
1138 prel_mod <- getPrelude
1139 setContextKeepingPackageModules prev keep_ctxt ([], [prel_mod])
1140 setContextAfterLoad prev keep_ctxt ms = do
1141 -- load a target if one is available, otherwise load the topmost module.
1142 targets <- GHC.getTargets
1143 case [ m | Just m <- map (findTarget ms) targets ] of
1145 let graph' = flattenSCCs (GHC.topSortModuleGraph True ms Nothing) in
1146 load_this (last graph')
1151 = case filter (`matches` t) ms of
1155 summary `matches` Target (TargetModule m) _ _
1156 = GHC.ms_mod_name summary == m
1157 summary `matches` Target (TargetFile f _) _ _
1158 | Just f' <- GHC.ml_hs_file (GHC.ms_location summary) = f == f'
1162 load_this summary | m <- GHC.ms_mod summary = do
1163 b <- GHC.moduleIsInterpreted m
1164 if b then setContextKeepingPackageModules prev keep_ctxt ([m], [])
1166 prel_mod <- getPrelude
1167 setContextKeepingPackageModules prev keep_ctxt ([],[prel_mod,m])
1169 -- | Keep any package modules (except Prelude) when changing the context.
1170 setContextKeepingPackageModules
1171 :: ([Module],[Module]) -- previous context
1172 -> Bool -- re-execute :module commands
1173 -> ([Module],[Module]) -- new context
1175 setContextKeepingPackageModules prev_context keep_ctxt (as,bs) = do
1176 let (_,bs0) = prev_context
1177 prel_mod <- getPrelude
1178 let pkg_modules = filter (\p -> not (isHomeModule p) && p /= prel_mod) bs0
1179 let bs1 = if null as then nub (prel_mod : bs) else bs
1180 GHC.setContext as (nub (bs1 ++ pkg_modules))
1184 mapM_ (playCtxtCmd False) (remembered_ctx st)
1187 setGHCiState st{ remembered_ctx = [] }
1189 isHomeModule :: Module -> Bool
1190 isHomeModule mod = GHC.modulePackageId mod == mainPackageId
1192 modulesLoadedMsg :: SuccessFlag -> [ModuleName] -> GHCi ()
1193 modulesLoadedMsg ok mods = do
1194 dflags <- getDynFlags
1195 when (verbosity dflags > 0) $ do
1197 | null mods = text "none."
1198 | otherwise = hsep (
1199 punctuate comma (map ppr mods)) <> text "."
1202 io (putStrLn (showSDoc (text "Failed, modules loaded: " <> mod_commas)))
1204 io (putStrLn (showSDoc (text "Ok, modules loaded: " <> mod_commas)))
1207 typeOfExpr :: String -> GHCi ()
1209 = handleSourceError (\e -> GHC.printExceptionAndWarnings e) $ do
1210 ty <- GHC.exprType str
1211 dflags <- getDynFlags
1212 let pefas = dopt Opt_PrintExplicitForalls dflags
1213 printForUser $ text str <+> dcolon
1214 <+> pprTypeForUser pefas ty
1216 kindOfType :: String -> GHCi ()
1218 = handleSourceError (\e -> GHC.printExceptionAndWarnings e) $ do
1219 ty <- GHC.typeKind str
1220 printForUser $ text str <+> dcolon <+> ppr ty
1222 quit :: String -> GHCi Bool
1223 quit _ = return True
1225 shellEscape :: String -> GHCi Bool
1226 shellEscape str = io (system str >> return False)
1228 -----------------------------------------------------------------------------
1229 -- Browsing a module's contents
1231 browseCmd :: Bool -> String -> GHCi ()
1234 ['*':s] | looksLikeModuleName s -> do
1235 m <- wantInterpretedModule s
1236 browseModule bang m False
1237 [s] | looksLikeModuleName s -> do
1239 browseModule bang m True
1241 (as,bs) <- GHC.getContext
1242 -- Guess which module the user wants to browse. Pick
1243 -- modules that are interpreted first. The most
1244 -- recently-added module occurs last, it seems.
1246 (as@(_:_), _) -> browseModule bang (last as) True
1247 ([], bs@(_:_)) -> browseModule bang (last bs) True
1248 ([], []) -> ghcError (CmdLineError ":browse: no current module")
1249 _ -> ghcError (CmdLineError "syntax: :browse <module>")
1251 -- without bang, show items in context of their parents and omit children
1252 -- with bang, show class methods and data constructors separately, and
1253 -- indicate import modules, to aid qualifying unqualified names
1254 -- with sorted, sort items alphabetically
1255 browseModule :: Bool -> Module -> Bool -> GHCi ()
1256 browseModule bang modl exports_only = do
1257 -- :browse! reports qualifiers wrt current context
1258 current_unqual <- GHC.getPrintUnqual
1259 -- Temporarily set the context to the module we're interested in,
1260 -- just so we can get an appropriate PrintUnqualified
1261 (as,bs) <- GHC.getContext
1262 prel_mod <- getPrelude
1263 if exports_only then GHC.setContext [] [prel_mod,modl]
1264 else GHC.setContext [modl] []
1265 target_unqual <- GHC.getPrintUnqual
1266 GHC.setContext as bs
1268 let unqual = if bang then current_unqual else target_unqual
1270 mb_mod_info <- GHC.getModuleInfo modl
1272 Nothing -> ghcError (CmdLineError ("unknown module: " ++
1273 GHC.moduleNameString (GHC.moduleName modl)))
1275 dflags <- getDynFlags
1277 | exports_only = GHC.modInfoExports mod_info
1278 | otherwise = GHC.modInfoTopLevelScope mod_info
1281 -- sort alphabetically name, but putting
1282 -- locally-defined identifiers first.
1283 -- We would like to improve this; see #1799.
1284 sorted_names = loc_sort local ++ occ_sort external
1286 (local,external) = ASSERT( all isExternalName names )
1287 partition ((==modl) . nameModule) names
1288 occ_sort = sortBy (compare `on` nameOccName)
1289 -- try to sort by src location. If the first name in
1290 -- our list has a good source location, then they all should.
1292 | n:_ <- names, isGoodSrcSpan (nameSrcSpan n)
1293 = sortBy (compare `on` nameSrcSpan) names
1297 mb_things <- mapM GHC.lookupName sorted_names
1298 let filtered_things = filterOutChildren (\t -> t) (catMaybes mb_things)
1300 rdr_env <- GHC.getGRE
1302 let pefas = dopt Opt_PrintExplicitForalls dflags
1303 things | bang = catMaybes mb_things
1304 | otherwise = filtered_things
1305 pretty | bang = pprTyThing
1306 | otherwise = pprTyThingInContext
1308 labels [] = text "-- not currently imported"
1309 labels l = text $ intercalate "\n" $ map qualifier l
1310 qualifier = maybe "-- defined locally"
1311 (("-- imported via "++) . intercalate ", "
1312 . map GHC.moduleNameString)
1313 importInfo = RdrName.getGRE_NameQualifier_maybes rdr_env
1314 modNames = map (importInfo . GHC.getName) things
1316 -- annotate groups of imports with their import modules
1317 -- the default ordering is somewhat arbitrary, so we group
1318 -- by header and sort groups; the names themselves should
1319 -- really come in order of source appearance.. (trac #1799)
1320 annotate mts = concatMap (\(m,ts)->labels m:ts)
1321 $ sortBy cmpQualifiers $ group mts
1322 where cmpQualifiers =
1323 compare `on` (map (fmap (map moduleNameFS)) . fst)
1325 group mts@((m,_):_) = (m,map snd g) : group ng
1326 where (g,ng) = partition ((==m).fst) mts
1328 let prettyThings = map (pretty pefas) things
1329 prettyThings' | bang = annotate $ zip modNames prettyThings
1330 | otherwise = prettyThings
1331 io (putStrLn $ showSDocForUser unqual (vcat prettyThings'))
1332 -- ToDo: modInfoInstances currently throws an exception for
1333 -- package modules. When it works, we can do this:
1334 -- $$ vcat (map GHC.pprInstance (GHC.modInfoInstances mod_info))
1336 -----------------------------------------------------------------------------
1337 -- Setting the module context
1339 setContext :: String -> GHCi ()
1341 | all sensible strs = do
1342 playCtxtCmd True (cmd, as, bs)
1344 setGHCiState st{ remembered_ctx = remembered_ctx st ++ [(cmd,as,bs)] }
1345 | otherwise = ghcError (CmdLineError "syntax: :module [+/-] [*]M1 ... [*]Mn")
1347 (cmd, strs, as, bs) =
1349 '+':stuff -> rest AddModules stuff
1350 '-':stuff -> rest RemModules stuff
1351 stuff -> rest SetContext stuff
1353 rest cmd stuff = (cmd, strs, as, bs)
1354 where strs = words stuff
1355 (as,bs) = partitionWith starred strs
1357 sensible ('*':m) = looksLikeModuleName m
1358 sensible m = looksLikeModuleName m
1360 starred ('*':m) = Left m
1363 playCtxtCmd :: Bool -> (CtxtCmd, [String], [String]) -> GHCi ()
1364 playCtxtCmd fail (cmd, as, bs)
1366 (as',bs') <- do_checks fail
1367 (prev_as,prev_bs) <- GHC.getContext
1371 prel_mod <- getPrelude
1372 let bs'' = if null as && prel_mod `notElem` bs' then prel_mod:bs'
1376 let as_to_add = as' \\ (prev_as ++ prev_bs)
1377 bs_to_add = bs' \\ (prev_as ++ prev_bs)
1378 return (prev_as ++ as_to_add, prev_bs ++ bs_to_add)
1380 let new_as = prev_as \\ (as' ++ bs')
1381 new_bs = prev_bs \\ (as' ++ bs')
1382 return (new_as, new_bs)
1383 GHC.setContext new_as new_bs
1386 as' <- mapM wantInterpretedModule as
1387 bs' <- mapM lookupModule bs
1389 do_checks False = do
1390 as' <- mapM (trymaybe . wantInterpretedModule) as
1391 bs' <- mapM (trymaybe . lookupModule) bs
1392 return (catMaybes as', catMaybes bs')
1397 Left _ -> return Nothing
1398 Right a -> return (Just a)
1400 ----------------------------------------------------------------------------
1403 -- set options in the interpreter. Syntax is exactly the same as the
1404 -- ghc command line, except that certain options aren't available (-C,
1407 -- This is pretty fragile: most options won't work as expected. ToDo:
1408 -- figure out which ones & disallow them.
1410 setCmd :: String -> GHCi ()
1412 = do st <- getGHCiState
1413 let opts = options st
1414 io $ putStrLn (showSDoc (
1415 text "options currently set: " <>
1418 else hsep (map (\o -> char '+' <> text (optToStr o)) opts)
1420 dflags <- getDynFlags
1421 io $ putStrLn (showSDoc (
1422 vcat (text "GHCi-specific dynamic flag settings:"
1423 :map (flagSetting dflags) ghciFlags)
1425 io $ putStrLn (showSDoc (
1426 vcat (text "other dynamic, non-language, flag settings:"
1427 :map (flagSetting dflags) nonLanguageDynFlags)
1429 where flagSetting dflags (str, f, _)
1430 | dopt f dflags = text " " <> text "-f" <> text str
1431 | otherwise = text " " <> text "-fno-" <> text str
1432 (ghciFlags,others) = partition (\(_, f, _) -> f `elem` flags)
1434 nonLanguageDynFlags = filterOut (\(_, f, _) -> f `elem` languageOptions)
1436 flags = [Opt_PrintExplicitForalls
1437 ,Opt_PrintBindResult
1438 ,Opt_BreakOnException
1440 ,Opt_PrintEvldWithShow
1443 = case getCmd str of
1444 Right ("args", rest) ->
1446 Left err -> io (hPutStrLn stderr err)
1447 Right args -> setArgs args
1448 Right ("prog", rest) ->
1450 Right [prog] -> setProg prog
1451 _ -> io (hPutStrLn stderr "syntax: :set prog <progname>")
1452 Right ("prompt", rest) -> setPrompt $ dropWhile isSpace rest
1453 Right ("editor", rest) -> setEditor $ dropWhile isSpace rest
1454 Right ("stop", rest) -> setStop $ dropWhile isSpace rest
1455 _ -> case toArgs str of
1456 Left err -> io (hPutStrLn stderr err)
1457 Right wds -> setOptions wds
1459 setArgs, setOptions :: [String] -> GHCi ()
1460 setProg, setEditor, setStop, setPrompt :: String -> GHCi ()
1464 setGHCiState st{ args = args }
1468 setGHCiState st{ progname = prog }
1472 setGHCiState st{ editor = cmd }
1474 setStop str@(c:_) | isDigit c
1475 = do let (nm_str,rest) = break (not.isDigit) str
1478 let old_breaks = breaks st
1479 if all ((/= nm) . fst) old_breaks
1480 then printForUser (text "Breakpoint" <+> ppr nm <+>
1481 text "does not exist")
1483 let new_breaks = map fn old_breaks
1484 fn (i,loc) | i == nm = (i,loc { onBreakCmd = dropWhile isSpace rest })
1485 | otherwise = (i,loc)
1486 setGHCiState st{ breaks = new_breaks }
1489 setGHCiState st{ stop = cmd }
1491 setPrompt value = do
1494 then io $ hPutStrLn stderr $ "syntax: :set prompt <prompt>, currently \"" ++ prompt st ++ "\""
1496 '\"' : _ -> case reads value of
1497 [(value', xs)] | all isSpace xs ->
1498 setGHCiState (st { prompt = value' })
1500 io $ hPutStrLn stderr "Can't parse prompt string. Use Haskell syntax."
1501 _ -> setGHCiState (st { prompt = value })
1504 do -- first, deal with the GHCi opts (+s, +t, etc.)
1505 let (plus_opts, minus_opts) = partitionWith isPlus wds
1506 mapM_ setOpt plus_opts
1507 -- then, dynamic flags
1508 newDynFlags minus_opts
1510 newDynFlags :: [String] -> GHCi ()
1511 newDynFlags minus_opts = do
1512 dflags <- getDynFlags
1513 let pkg_flags = packageFlags dflags
1514 (dflags', leftovers, warns) <- io $ GHC.parseDynamicFlags dflags $ map noLoc minus_opts
1515 io $ handleFlagWarnings dflags' warns
1517 if (not (null leftovers))
1518 then ghcError $ errorsToGhcException leftovers
1521 new_pkgs <- setDynFlags dflags'
1523 -- if the package flags changed, we should reset the context
1524 -- and link the new packages.
1525 dflags <- getDynFlags
1526 when (packageFlags dflags /= pkg_flags) $ do
1527 io $ hPutStrLn stderr "package flags have changed, resetting and loading new packages..."
1529 GHC.load LoadAllTargets
1530 io (linkPackages dflags new_pkgs)
1531 -- package flags changed, we can't re-use any of the old context
1532 setContextAfterLoad ([],[]) False []
1536 unsetOptions :: String -> GHCi ()
1538 = do -- first, deal with the GHCi opts (+s, +t, etc.)
1539 let opts = words str
1540 (minus_opts, rest1) = partition isMinus opts
1541 (plus_opts, rest2) = partitionWith isPlus rest1
1543 if (not (null rest2))
1544 then io (putStrLn ("unknown option: '" ++ head rest2 ++ "'"))
1547 mapM_ unsetOpt plus_opts
1549 let no_flag ('-':'f':rest) = return ("-fno-" ++ rest)
1550 no_flag f = ghcError (ProgramError ("don't know how to reverse " ++ f))
1552 no_flags <- mapM no_flag minus_opts
1553 newDynFlags no_flags
1555 isMinus :: String -> Bool
1556 isMinus ('-':_) = True
1559 isPlus :: String -> Either String String
1560 isPlus ('+':opt) = Left opt
1561 isPlus other = Right other
1563 setOpt, unsetOpt :: String -> GHCi ()
1566 = case strToGHCiOpt str of
1567 Nothing -> io (putStrLn ("unknown option: '" ++ str ++ "'"))
1568 Just o -> setOption o
1571 = case strToGHCiOpt str of
1572 Nothing -> io (putStrLn ("unknown option: '" ++ str ++ "'"))
1573 Just o -> unsetOption o
1575 strToGHCiOpt :: String -> (Maybe GHCiOption)
1576 strToGHCiOpt "s" = Just ShowTiming
1577 strToGHCiOpt "t" = Just ShowType
1578 strToGHCiOpt "r" = Just RevertCAFs
1579 strToGHCiOpt _ = Nothing
1581 optToStr :: GHCiOption -> String
1582 optToStr ShowTiming = "s"
1583 optToStr ShowType = "t"
1584 optToStr RevertCAFs = "r"
1586 -- ---------------------------------------------------------------------------
1589 showCmd :: String -> GHCi ()
1593 ["args"] -> io $ putStrLn (show (args st))
1594 ["prog"] -> io $ putStrLn (show (progname st))
1595 ["prompt"] -> io $ putStrLn (show (prompt st))
1596 ["editor"] -> io $ putStrLn (show (editor st))
1597 ["stop"] -> io $ putStrLn (show (stop st))
1598 ["modules" ] -> showModules
1599 ["bindings"] -> showBindings
1600 ["linker"] -> io showLinkerState
1601 ["breaks"] -> showBkptTable
1602 ["context"] -> showContext
1603 ["packages"] -> showPackages
1604 ["languages"] -> showLanguages
1605 _ -> ghcError (CmdLineError ("syntax: :show [ args | prog | prompt | editor | stop | modules | bindings\n"++
1606 " | breaks | context | packages | languages ]"))
1608 showModules :: GHCi ()
1610 loaded_mods <- getLoadedModules
1611 -- we want *loaded* modules only, see #1734
1612 let show_one ms = do m <- GHC.showModule ms; io (putStrLn m)
1613 mapM_ show_one loaded_mods
1615 getLoadedModules :: GHCi [GHC.ModSummary]
1616 getLoadedModules = do
1617 graph <- GHC.getModuleGraph
1618 filterM (GHC.isLoaded . GHC.ms_mod_name) graph
1620 showBindings :: GHCi ()
1622 bindings <- GHC.getBindings
1623 docs <- pprTypeAndContents
1624 [ id | AnId id <- sortBy compareTyThings bindings]
1625 printForUserPartWay docs
1627 compareTyThings :: TyThing -> TyThing -> Ordering
1628 t1 `compareTyThings` t2 = getName t1 `compareNames` getName t2
1630 printTyThing :: TyThing -> GHCi ()
1631 printTyThing tyth = do dflags <- getDynFlags
1632 let pefas = dopt Opt_PrintExplicitForalls dflags
1633 printForUser (pprTyThing pefas tyth)
1635 showBkptTable :: GHCi ()
1638 printForUser $ prettyLocations (breaks st)
1640 showContext :: GHCi ()
1642 resumes <- GHC.getResumeContext
1643 printForUser $ vcat (map pp_resume (reverse resumes))
1646 ptext (sLit "--> ") <> text (GHC.resumeStmt resume)
1647 $$ nest 2 (ptext (sLit "Stopped at") <+> ppr (GHC.resumeSpan resume))
1649 showPackages :: GHCi ()
1651 pkg_flags <- fmap packageFlags getDynFlags
1652 io $ putStrLn $ showSDoc $ vcat $
1653 text ("active package flags:"++if null pkg_flags then " none" else "")
1654 : map showFlag pkg_flags
1655 pkg_ids <- fmap (preloadPackages . pkgState) getDynFlags
1656 io $ putStrLn $ showSDoc $ vcat $
1657 text "packages currently loaded:"
1658 : map (nest 2 . text . packageIdString)
1659 (sortBy (compare `on` packageIdFS) pkg_ids)
1660 where showFlag (ExposePackage p) = text $ " -package " ++ p
1661 showFlag (HidePackage p) = text $ " -hide-package " ++ p
1662 showFlag (IgnorePackage p) = text $ " -ignore-package " ++ p
1664 showLanguages :: GHCi ()
1666 dflags <- getDynFlags
1667 io $ putStrLn $ showSDoc $ vcat $
1668 text "active language flags:" :
1669 [text (" -X" ++ str) | (str, f, _) <- DynFlags.xFlags, dopt f dflags]
1671 -- -----------------------------------------------------------------------------
1674 completeNone :: String -> IO [String]
1675 completeNone _w = return []
1677 completeMacro, completeIdentifier, completeModule,
1678 completeHomeModule, completeSetOptions, completeFilename,
1679 completeHomeModuleOrFile
1680 :: String -> IO [String]
1683 completeWord :: String -> Int -> Int -> IO (Maybe (String, [String]))
1684 completeWord w start end = do
1685 line <- Readline.getLineBuffer
1686 let line_words = words (dropWhile isSpace line)
1688 ':':_ | all isSpace (take (start-1) line) -> wrapCompleter completeCmd w
1690 | ((':':c) : _) <- line_words -> do
1691 completionVars <- lookupCompletionVars c
1692 case completionVars of
1693 (Nothing,complete) -> wrapCompleter complete w
1694 (Just breakChars,complete)
1695 -> let (n,w') = selectWord
1696 (words' (`elem` breakChars) 0 line)
1697 complete' w = do rets <- complete w
1698 return (map (drop n) rets)
1699 in wrapCompleter complete' w'
1700 | ("import" : _) <- line_words ->
1701 wrapCompleter completeModule w
1703 --printf "complete %s, start = %d, end = %d\n" w start end
1704 wrapCompleter completeIdentifier w
1705 where words' _ _ [] = []
1706 words' isBreak n str = let (w,r) = break isBreak str
1707 (s,r') = span isBreak r
1708 in (n,w):words' isBreak (n+length w+length s) r'
1709 -- In a Haskell expression we want to parse 'a-b' as three words
1710 -- where a compiler flag (e.g. -ddump-simpl) should
1711 -- only be a single word.
1712 selectWord [] = (0,w)
1713 selectWord ((offset,x):xs)
1714 | offset+length x >= start = (start-offset,take (end-offset) x)
1715 | otherwise = selectWord xs
1717 lookupCompletionVars ('!':_) = return (Just filenameWordBreakChars,
1719 lookupCompletionVars c = do
1720 maybe_cmd <- lookupCommand' c
1722 Just (_,_,ws,f) -> return (ws,f)
1723 Nothing -> return (Just filenameWordBreakChars,
1727 completeCmd :: String -> IO [String]
1729 cmds <- readIORef macros_ref
1730 return (filter (w `isPrefixOf`) (map (':':)
1731 (map cmdName (builtin_commands ++ cmds))))
1733 completeMacro w = do
1734 cmds <- readIORef macros_ref
1735 return (filter (w `isPrefixOf`) (map cmdName cmds))
1737 completeIdentifier w = do
1738 rdrs <- withRestoredSession GHC.getRdrNamesInScope
1739 return (filter (w `isPrefixOf`) (map (showSDoc.ppr) rdrs))
1741 completeModule w = do
1742 dflags <- withRestoredSession GHC.getSessionDynFlags
1743 let pkg_mods = allExposedModules dflags
1744 return (filter (w `isPrefixOf`) (map (showSDoc.ppr) pkg_mods))
1746 completeHomeModule w = do
1747 g <- withRestoredSession GHC.getModuleGraph
1748 let home_mods = map GHC.ms_mod_name g
1749 return (filter (w `isPrefixOf`) (map (showSDoc.ppr) home_mods))
1751 completeSetOptions w = do
1752 return (filter (w `isPrefixOf`) options)
1753 where options = "args":"prog":flagList
1754 flagList = map head $ group $ sort allFlags
1756 completeFilename w = do
1757 ws <- Readline.filenameCompletionFunction w
1759 -- If we only found one result, and it's a directory,
1760 -- add a trailing slash.
1762 isDir <- expandPathIO file >>= doesDirectoryExist
1763 if isDir && last file /= '/'
1764 then return [file ++ "/"]
1769 completeHomeModuleOrFile = unionComplete completeHomeModule completeFilename
1771 unionComplete :: (String -> IO [String]) -> (String -> IO [String]) -> String -> IO [String]
1772 unionComplete f1 f2 w = do
1777 wrapCompleter :: (String -> IO [String]) -> String -> IO (Maybe (String,[String]))
1778 wrapCompleter fun w = do
1781 [] -> Readline.setAttemptedCompletionOver True >> return Nothing
1782 [x] -> -- Add a trailing space, unless it already has an appended slash.
1783 let appended = if last x == '/' then x else x ++ " "
1784 in return (Just (appended,[]))
1785 xs -> case getCommonPrefix xs of
1786 "" -> return (Just ("",xs))
1787 pref -> return (Just (pref,xs))
1789 getCommonPrefix :: [String] -> String
1790 getCommonPrefix [] = ""
1791 getCommonPrefix (s:ss) = foldl common s ss
1792 where common _s "" = ""
1794 common (c:cs) (d:ds)
1795 | c == d = c : common cs ds
1798 allExposedModules :: DynFlags -> [ModuleName]
1799 allExposedModules dflags
1800 = concat (map exposedModules (filter exposed (eltsUFM pkg_db)))
1802 pkg_db = pkgIdMap (pkgState dflags)
1804 completeMacro = completeNone
1805 completeIdentifier = completeNone
1806 completeModule = completeNone
1807 completeHomeModule = completeNone
1808 completeSetOptions = completeNone
1809 completeFilename = completeNone
1810 completeHomeModuleOrFile=completeNone
1813 -- ---------------------------------------------------------------------------
1814 -- User code exception handling
1816 -- This is the exception handler for exceptions generated by the
1817 -- user's code and exceptions coming from children sessions;
1818 -- it normally just prints out the exception. The
1819 -- handler must be recursive, in case showing the exception causes
1820 -- more exceptions to be raised.
1822 -- Bugfix: if the user closed stdout or stderr, the flushing will fail,
1823 -- raising another exception. We therefore don't put the recursive
1824 -- handler arond the flushing operation, so if stderr is closed
1825 -- GHCi will just die gracefully rather than going into an infinite loop.
1826 handler :: SomeException -> GHCi Bool
1828 handler exception = do
1830 io installSignalHandlers
1831 ghciHandle handler (showException exception >> return False)
1833 showException :: SomeException -> GHCi ()
1835 io $ case fromException se of
1836 Just Interrupted -> putStrLn "Interrupted."
1837 -- omit the location for CmdLineError:
1838 Just (CmdLineError s) -> putStrLn s
1840 Just ph@(PhaseFailed {}) -> putStrLn (showGhcException ph "")
1841 Just other_ghc_ex -> print other_ghc_ex
1842 Nothing -> putStrLn ("*** Exception: " ++ show se)
1844 -----------------------------------------------------------------------------
1845 -- recursive exception handlers
1847 -- Don't forget to unblock async exceptions in the handler, or if we're
1848 -- in an exception loop (eg. let a = error a in a) the ^C exception
1849 -- may never be delivered. Thanks to Marcin for pointing out the bug.
1851 ghciHandle :: (SomeException -> GHCi a) -> GHCi a -> GHCi a
1852 ghciHandle h (GHCi m) = GHCi $ \s ->
1854 (\e -> unGHCi (ghciUnblock (h e)) s)
1856 ghciUnblock :: GHCi a -> GHCi a
1857 ghciUnblock (GHCi a) =
1858 GHCi $ \s -> reifyGhc $ \gs ->
1859 Exception.unblock (reflectGhc (a s) gs)
1861 ghciTry :: GHCi a -> GHCi (Either SomeException a)
1862 ghciTry (GHCi m) = GHCi $ \s -> gtry (m s)
1864 -- ----------------------------------------------------------------------------
1867 expandPath :: String -> GHCi String
1868 expandPath path = io (expandPathIO path)
1870 expandPathIO :: String -> IO String
1872 case dropWhile isSpace path of
1874 tilde <- getHomeDirectory -- will fail if HOME not defined
1875 return (tilde ++ '/':d)
1879 wantInterpretedModule :: String -> GHCi Module
1880 wantInterpretedModule str = do
1881 modl <- lookupModule str
1882 dflags <- getDynFlags
1883 when (GHC.modulePackageId modl /= thisPackage dflags) $
1884 ghcError (CmdLineError ("module '" ++ str ++ "' is from another package;\nthis command requires an interpreted module"))
1885 is_interpreted <- GHC.moduleIsInterpreted modl
1886 when (not is_interpreted) $
1887 ghcError (CmdLineError ("module '" ++ str ++ "' is not interpreted; try \':add *" ++ str ++ "' first"))
1890 wantNameFromInterpretedModule :: (Name -> SDoc -> GHCi ()) -> String
1891 -> (Name -> GHCi ())
1893 wantNameFromInterpretedModule noCanDo str and_then =
1894 handleSourceError (GHC.printExceptionAndWarnings) $ do
1895 names <- GHC.parseName str
1899 let modl = ASSERT( isExternalName n ) GHC.nameModule n
1900 if not (GHC.isExternalName n)
1901 then noCanDo n $ ppr n <>
1902 text " is not defined in an interpreted module"
1904 is_interpreted <- GHC.moduleIsInterpreted modl
1905 if not is_interpreted
1906 then noCanDo n $ text "module " <> ppr modl <>
1907 text " is not interpreted"
1910 -- -----------------------------------------------------------------------------
1911 -- commands for debugger
1913 sprintCmd, printCmd, forceCmd :: String -> GHCi ()
1914 sprintCmd = pprintCommand False False
1915 printCmd = pprintCommand True False
1916 forceCmd = pprintCommand False True
1918 pprintCommand :: Bool -> Bool -> String -> GHCi ()
1919 pprintCommand bind force str = do
1920 pprintClosureCommand bind force str
1922 stepCmd :: String -> GHCi ()
1923 stepCmd [] = doContinue (const True) GHC.SingleStep
1924 stepCmd expression = do runStmt expression GHC.SingleStep; return ()
1926 stepLocalCmd :: String -> GHCi ()
1927 stepLocalCmd [] = do
1928 mb_span <- getCurrentBreakSpan
1930 Nothing -> stepCmd []
1932 Just mod <- getCurrentBreakModule
1933 current_toplevel_decl <- enclosingTickSpan mod loc
1934 doContinue (`isSubspanOf` current_toplevel_decl) GHC.SingleStep
1936 stepLocalCmd expression = stepCmd expression
1938 stepModuleCmd :: String -> GHCi ()
1939 stepModuleCmd [] = do
1940 mb_span <- getCurrentBreakSpan
1942 Nothing -> stepCmd []
1944 Just span <- getCurrentBreakSpan
1945 let f some_span = srcSpanFileName_maybe span == srcSpanFileName_maybe some_span
1946 doContinue f GHC.SingleStep
1948 stepModuleCmd expression = stepCmd expression
1950 -- | Returns the span of the largest tick containing the srcspan given
1951 enclosingTickSpan :: Module -> SrcSpan -> GHCi SrcSpan
1952 enclosingTickSpan mod src = do
1953 ticks <- getTickArray mod
1954 let line = srcSpanStartLine src
1955 ASSERT (inRange (bounds ticks) line) do
1956 let enclosing_spans = [ span | (_,span) <- ticks ! line
1957 , srcSpanEnd span >= srcSpanEnd src]
1958 return . head . sortBy leftmost_largest $ enclosing_spans
1960 traceCmd :: String -> GHCi ()
1961 traceCmd [] = doContinue (const True) GHC.RunAndLogSteps
1962 traceCmd expression = do runStmt expression GHC.RunAndLogSteps; return ()
1964 continueCmd :: String -> GHCi ()
1965 continueCmd = noArgs $ doContinue (const True) GHC.RunToCompletion
1967 -- doContinue :: SingleStep -> GHCi ()
1968 doContinue :: (SrcSpan -> Bool) -> SingleStep -> GHCi ()
1969 doContinue pred step = do
1970 runResult <- resume step
1971 afterRunStmt pred runResult
1974 abandonCmd :: String -> GHCi ()
1975 abandonCmd = noArgs $ do
1976 b <- GHC.abandon -- the prompt will change to indicate the new context
1977 when (not b) $ io $ putStrLn "There is no computation running."
1980 deleteCmd :: String -> GHCi ()
1981 deleteCmd argLine = do
1982 deleteSwitch $ words argLine
1984 deleteSwitch :: [String] -> GHCi ()
1986 io $ putStrLn "The delete command requires at least one argument."
1987 -- delete all break points
1988 deleteSwitch ("*":_rest) = discardActiveBreakPoints
1989 deleteSwitch idents = do
1990 mapM_ deleteOneBreak idents
1992 deleteOneBreak :: String -> GHCi ()
1994 | all isDigit str = deleteBreak (read str)
1995 | otherwise = return ()
1997 historyCmd :: String -> GHCi ()
1999 | null arg = history 20
2000 | all isDigit arg = history (read arg)
2001 | otherwise = io $ putStrLn "Syntax: :history [num]"
2004 resumes <- GHC.getResumeContext
2006 [] -> io $ putStrLn "Not stopped at a breakpoint"
2008 let hist = GHC.resumeHistory r
2009 (took,rest) = splitAt num hist
2011 [] -> io $ putStrLn $
2012 "Empty history. Perhaps you forgot to use :trace?"
2014 spans <- mapM GHC.getHistorySpan took
2015 let nums = map (printf "-%-3d:") [(1::Int)..]
2016 names = map GHC.historyEnclosingDecl took
2017 printForUser (vcat(zipWith3
2018 (\x y z -> x <+> y <+> z)
2020 (map (bold . ppr) names)
2021 (map (parens . ppr) spans)))
2022 io $ putStrLn $ if null rest then "<end of history>" else "..."
2024 bold :: SDoc -> SDoc
2025 bold c | do_bold = text start_bold <> c <> text end_bold
2028 backCmd :: String -> GHCi ()
2029 backCmd = noArgs $ do
2030 (names, _, span) <- GHC.back
2031 printForUser $ ptext (sLit "Logged breakpoint at") <+> ppr span
2032 printTypeOfNames names
2033 -- run the command set with ":set stop <cmd>"
2035 enqueueCommands [stop st]
2037 forwardCmd :: String -> GHCi ()
2038 forwardCmd = noArgs $ do
2039 (names, ix, span) <- GHC.forward
2040 printForUser $ (if (ix == 0)
2041 then ptext (sLit "Stopped at")
2042 else ptext (sLit "Logged breakpoint at")) <+> ppr span
2043 printTypeOfNames names
2044 -- run the command set with ":set stop <cmd>"
2046 enqueueCommands [stop st]
2048 -- handle the "break" command
2049 breakCmd :: String -> GHCi ()
2050 breakCmd argLine = do
2051 breakSwitch $ words argLine
2053 breakSwitch :: [String] -> GHCi ()
2055 io $ putStrLn "The break command requires at least one argument."
2056 breakSwitch (arg1:rest)
2057 | looksLikeModuleName arg1 && not (null rest) = do
2058 mod <- wantInterpretedModule arg1
2059 breakByModule mod rest
2060 | all isDigit arg1 = do
2061 (toplevel, _) <- GHC.getContext
2063 (mod : _) -> breakByModuleLine mod (read arg1) rest
2065 io $ putStrLn "Cannot find default module for breakpoint."
2066 io $ putStrLn "Perhaps no modules are loaded for debugging?"
2067 | otherwise = do -- try parsing it as an identifier
2068 wantNameFromInterpretedModule noCanDo arg1 $ \name -> do
2069 let loc = GHC.srcSpanStart (GHC.nameSrcSpan name)
2070 if GHC.isGoodSrcLoc loc
2071 then ASSERT( isExternalName name )
2072 findBreakAndSet (GHC.nameModule name) $
2073 findBreakByCoord (Just (GHC.srcLocFile loc))
2074 (GHC.srcLocLine loc,
2076 else noCanDo name $ text "can't find its location: " <> ppr loc
2078 noCanDo n why = printForUser $
2079 text "cannot set breakpoint on " <> ppr n <> text ": " <> why
2081 breakByModule :: Module -> [String] -> GHCi ()
2082 breakByModule mod (arg1:rest)
2083 | all isDigit arg1 = do -- looks like a line number
2084 breakByModuleLine mod (read arg1) rest
2088 breakByModuleLine :: Module -> Int -> [String] -> GHCi ()
2089 breakByModuleLine mod line args
2090 | [] <- args = findBreakAndSet mod $ findBreakByLine line
2091 | [col] <- args, all isDigit col =
2092 findBreakAndSet mod $ findBreakByCoord Nothing (line, read col)
2093 | otherwise = breakSyntax
2096 breakSyntax = ghcError (CmdLineError "Syntax: :break [<mod>] <line> [<column>]")
2098 findBreakAndSet :: Module -> (TickArray -> Maybe (Int, SrcSpan)) -> GHCi ()
2099 findBreakAndSet mod lookupTickTree = do
2100 tickArray <- getTickArray mod
2101 (breakArray, _) <- getModBreak mod
2102 case lookupTickTree tickArray of
2103 Nothing -> io $ putStrLn $ "No breakpoints found at that location."
2104 Just (tick, span) -> do
2105 success <- io $ setBreakFlag True breakArray tick
2109 recordBreak $ BreakLocation
2116 text "Breakpoint " <> ppr nm <>
2118 then text " was already set at " <> ppr span
2119 else text " activated at " <> ppr span
2121 printForUser $ text "Breakpoint could not be activated at"
2124 -- When a line number is specified, the current policy for choosing
2125 -- the best breakpoint is this:
2126 -- - the leftmost complete subexpression on the specified line, or
2127 -- - the leftmost subexpression starting on the specified line, or
2128 -- - the rightmost subexpression enclosing the specified line
2130 findBreakByLine :: Int -> TickArray -> Maybe (BreakIndex,SrcSpan)
2131 findBreakByLine line arr
2132 | not (inRange (bounds arr) line) = Nothing
2134 listToMaybe (sortBy (leftmost_largest `on` snd) complete) `mplus`
2135 listToMaybe (sortBy (leftmost_smallest `on` snd) incomplete) `mplus`
2136 listToMaybe (sortBy (rightmost `on` snd) ticks)
2140 starts_here = [ tick | tick@(_,span) <- ticks,
2141 GHC.srcSpanStartLine span == line ]
2143 (complete,incomplete) = partition ends_here starts_here
2144 where ends_here (_,span) = GHC.srcSpanEndLine span == line
2146 findBreakByCoord :: Maybe FastString -> (Int,Int) -> TickArray
2147 -> Maybe (BreakIndex,SrcSpan)
2148 findBreakByCoord mb_file (line, col) arr
2149 | not (inRange (bounds arr) line) = Nothing
2151 listToMaybe (sortBy (rightmost `on` snd) contains ++
2152 sortBy (leftmost_smallest `on` snd) after_here)
2156 -- the ticks that span this coordinate
2157 contains = [ tick | tick@(_,span) <- ticks, span `spans` (line,col),
2158 is_correct_file span ]
2160 is_correct_file span
2161 | Just f <- mb_file = GHC.srcSpanFile span == f
2164 after_here = [ tick | tick@(_,span) <- ticks,
2165 GHC.srcSpanStartLine span == line,
2166 GHC.srcSpanStartCol span >= col ]
2168 -- For now, use ANSI bold on terminals that we know support it.
2169 -- Otherwise, we add a line of carets under the active expression instead.
2170 -- In particular, on Windows and when running the testsuite (which sets
2171 -- TERM to vt100 for other reasons) we get carets.
2172 -- We really ought to use a proper termcap/terminfo library.
2174 do_bold = (`isPrefixOf` unsafePerformIO mTerm) `any` ["xterm", "linux"]
2175 where mTerm = System.Environment.getEnv "TERM"
2176 `catchIO` \_ -> return "TERM not set"
2178 start_bold :: String
2179 start_bold = "\ESC[1m"
2181 end_bold = "\ESC[0m"
2183 listCmd :: String -> GHCi ()
2185 mb_span <- getCurrentBreakSpan
2188 printForUser $ text "Not stopped at a breakpoint; nothing to list"
2190 | GHC.isGoodSrcSpan span -> io $ listAround span True
2192 do resumes <- GHC.getResumeContext
2194 [] -> panic "No resumes"
2196 do let traceIt = case GHC.resumeHistory r of
2197 [] -> text "rerunning with :trace,"
2199 doWhat = traceIt <+> text ":back then :list"
2200 printForUser (text "Unable to list source for" <+>
2202 $$ text "Try" <+> doWhat)
2203 listCmd str = list2 (words str)
2205 list2 :: [String] -> GHCi ()
2206 list2 [arg] | all isDigit arg = do
2207 (toplevel, _) <- GHC.getContext
2209 [] -> io $ putStrLn "No module to list"
2210 (mod : _) -> listModuleLine mod (read arg)
2211 list2 [arg1,arg2] | looksLikeModuleName arg1, all isDigit arg2 = do
2212 mod <- wantInterpretedModule arg1
2213 listModuleLine mod (read arg2)
2215 wantNameFromInterpretedModule noCanDo arg $ \name -> do
2216 let loc = GHC.srcSpanStart (GHC.nameSrcSpan name)
2217 if GHC.isGoodSrcLoc loc
2219 tickArray <- ASSERT( isExternalName name )
2220 getTickArray (GHC.nameModule name)
2221 let mb_span = findBreakByCoord (Just (GHC.srcLocFile loc))
2222 (GHC.srcLocLine loc, GHC.srcLocCol loc)
2225 Nothing -> io $ listAround (GHC.srcLocSpan loc) False
2226 Just (_,span) -> io $ listAround span False
2228 noCanDo name $ text "can't find its location: " <>
2231 noCanDo n why = printForUser $
2232 text "cannot list source code for " <> ppr n <> text ": " <> why
2234 io $ putStrLn "syntax: :list [<line> | <module> <line> | <identifier>]"
2236 listModuleLine :: Module -> Int -> GHCi ()
2237 listModuleLine modl line = do
2238 graph <- GHC.getModuleGraph
2239 let this = filter ((== modl) . GHC.ms_mod) graph
2241 [] -> panic "listModuleLine"
2243 let filename = expectJust "listModuleLine" (ml_hs_file (GHC.ms_location summ))
2244 loc = GHC.mkSrcLoc (mkFastString (filename)) line 0
2245 io $ listAround (GHC.srcLocSpan loc) False
2247 -- | list a section of a source file around a particular SrcSpan.
2248 -- If the highlight flag is True, also highlight the span using
2249 -- start_bold\/end_bold.
2250 listAround :: SrcSpan -> Bool -> IO ()
2251 listAround span do_highlight = do
2252 contents <- BS.readFile (unpackFS file)
2254 lines = BS.split '\n' contents
2255 these_lines = take (line2 - line1 + 1 + pad_before + pad_after) $
2256 drop (line1 - 1 - pad_before) $ lines
2257 fst_line = max 1 (line1 - pad_before)
2258 line_nos = [ fst_line .. ]
2260 highlighted | do_highlight = zipWith highlight line_nos these_lines
2261 | otherwise = [\p -> BS.concat[p,l] | l <- these_lines]
2263 bs_line_nos = [ BS.pack (show l ++ " ") | l <- line_nos ]
2264 prefixed = zipWith ($) highlighted bs_line_nos
2266 BS.putStrLn (BS.intercalate (BS.pack "\n") prefixed)
2268 file = GHC.srcSpanFile span
2269 line1 = GHC.srcSpanStartLine span
2270 col1 = GHC.srcSpanStartCol span
2271 line2 = GHC.srcSpanEndLine span
2272 col2 = GHC.srcSpanEndCol span
2274 pad_before | line1 == 1 = 0
2278 highlight | do_bold = highlight_bold
2279 | otherwise = highlight_carets
2281 highlight_bold no line prefix
2282 | no == line1 && no == line2
2283 = let (a,r) = BS.splitAt col1 line
2284 (b,c) = BS.splitAt (col2-col1) r
2286 BS.concat [prefix, a,BS.pack start_bold,b,BS.pack end_bold,c]
2288 = let (a,b) = BS.splitAt col1 line in
2289 BS.concat [prefix, a, BS.pack start_bold, b]
2291 = let (a,b) = BS.splitAt col2 line in
2292 BS.concat [prefix, a, BS.pack end_bold, b]
2293 | otherwise = BS.concat [prefix, line]
2295 highlight_carets no line prefix
2296 | no == line1 && no == line2
2297 = BS.concat [prefix, line, nl, indent, BS.replicate col1 ' ',
2298 BS.replicate (col2-col1) '^']
2300 = BS.concat [indent, BS.replicate (col1 - 2) ' ', BS.pack "vv", nl,
2303 = BS.concat [prefix, line, nl, indent, BS.replicate col2 ' ',
2305 | otherwise = BS.concat [prefix, line]
2307 indent = BS.pack (" " ++ replicate (length (show no)) ' ')
2308 nl = BS.singleton '\n'
2310 -- --------------------------------------------------------------------------
2313 getTickArray :: Module -> GHCi TickArray
2314 getTickArray modl = do
2316 let arrmap = tickarrays st
2317 case lookupModuleEnv arrmap modl of
2318 Just arr -> return arr
2320 (_breakArray, ticks) <- getModBreak modl
2321 let arr = mkTickArray (assocs ticks)
2322 setGHCiState st{tickarrays = extendModuleEnv arrmap modl arr}
2325 discardTickArrays :: GHCi ()
2326 discardTickArrays = do
2328 setGHCiState st{tickarrays = emptyModuleEnv}
2330 mkTickArray :: [(BreakIndex,SrcSpan)] -> TickArray
2332 = accumArray (flip (:)) [] (1, max_line)
2333 [ (line, (nm,span)) | (nm,span) <- ticks,
2334 line <- srcSpanLines span ]
2336 max_line = foldr max 0 (map GHC.srcSpanEndLine (map snd ticks))
2337 srcSpanLines span = [ GHC.srcSpanStartLine span ..
2338 GHC.srcSpanEndLine span ]
2340 lookupModule :: String -> GHCi Module
2341 lookupModule modName
2342 = GHC.findModule (GHC.mkModuleName modName) Nothing
2344 -- don't reset the counter back to zero?
2345 discardActiveBreakPoints :: GHCi ()
2346 discardActiveBreakPoints = do
2348 mapM (turnOffBreak.snd) (breaks st)
2349 setGHCiState $ st { breaks = [] }
2351 deleteBreak :: Int -> GHCi ()
2352 deleteBreak identity = do
2354 let oldLocations = breaks st
2355 (this,rest) = partition (\loc -> fst loc == identity) oldLocations
2357 then printForUser (text "Breakpoint" <+> ppr identity <+>
2358 text "does not exist")
2360 mapM (turnOffBreak.snd) this
2361 setGHCiState $ st { breaks = rest }
2363 turnOffBreak :: BreakLocation -> GHCi Bool
2364 turnOffBreak loc = do
2365 (arr, _) <- getModBreak (breakModule loc)
2366 io $ setBreakFlag False arr (breakTick loc)
2368 getModBreak :: Module -> GHCi (GHC.BreakArray, Array Int SrcSpan)
2369 getModBreak mod = do
2370 Just mod_info <- GHC.getModuleInfo mod
2371 let modBreaks = GHC.modInfoModBreaks mod_info
2372 let array = GHC.modBreaks_flags modBreaks
2373 let ticks = GHC.modBreaks_locs modBreaks
2374 return (array, ticks)
2376 setBreakFlag :: Bool -> GHC.BreakArray -> Int -> IO Bool
2377 setBreakFlag toggle array index
2378 | toggle = GHC.setBreakOn array index
2379 | otherwise = GHC.setBreakOff array index