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 , handleFlagWarnings )
39 import qualified RdrName ( getGRE_NameQualifier_maybes ) -- should this come via GHC?
40 import Outputable hiding (printForUser, printForUserPartWay)
41 import Module -- for ModuleEnv
45 -- 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, completeShowOptions),
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 startGHCi (runGHCi srcs maybe_exprs)
344 GHCiState{ progname = "<interactive>",
348 editor = default_editor,
349 -- session = session,
354 tickarrays = emptyModuleEnv,
355 last_command = Nothing,
358 ghc_e = isJust maybe_exprs
363 Readline.stifleHistory 100
364 withGhcAppData (\dir -> Readline.writeHistory (dir </> "ghci_history"))
366 Readline.resetTerminal Nothing
371 withGhcAppData :: (FilePath -> IO a) -> IO a -> IO a
372 withGhcAppData right left = do
373 either_dir <- IO.try (getAppUserDataDirectory "ghc")
375 Right dir -> right dir
378 -- libedit doesn't always restore the terminal settings correctly (as of at
379 -- least 07/12/2008); see trac #2691. Work around this by manually resetting
380 -- the terminal outselves.
381 withTerminalReset :: Ghc () -> Ghc ()
382 #ifdef mingw32_HOST_OS
383 withTerminalReset = id
385 withTerminalReset f = do
386 isTTY <- liftIO $ hIsTerminalDevice stdout
389 else gbracket (liftIO $ getTerminalAttributes stdOutput)
390 (\attrs -> liftIO $ setTerminalAttributes stdOutput attrs Immediately)
394 runGHCi :: [(FilePath, Maybe Phase)] -> Maybe [String] -> GHCi ()
395 runGHCi paths maybe_exprs = do
397 read_dot_files = not opt_IgnoreDotGhci
399 current_dir = return (Just ".ghci")
401 app_user_dir = io $ withGhcAppData
402 (\dir -> return (Just (dir </> "ghci.conf")))
406 either_dir <- io $ IO.try (getEnv "HOME")
408 Right home -> return (Just (home </> ".ghci"))
411 sourceConfigFile :: FilePath -> GHCi ()
412 sourceConfigFile file = do
413 exists <- io $ doesFileExist file
415 dir_ok <- io $ checkPerms (getDirectory file)
416 file_ok <- io $ checkPerms file
417 when (dir_ok && file_ok) $ do
418 either_hdl <- io $ IO.try (openFile file ReadMode)
421 Right hdl -> runCommands (fileLoop hdl False False)
423 getDirectory f = case takeDirectory f of "" -> "."; d -> d
425 when (read_dot_files) $ do
426 cfgs0 <- sequence [ current_dir, app_user_dir, home_dir ]
427 cfgs <- io $ mapM canonicalizePath (catMaybes cfgs0)
428 mapM_ sourceConfigFile (nub cfgs)
429 -- nub, because we don't want to read .ghci twice if the
432 -- Perform a :load for files given on the GHCi command line
433 -- When in -e mode, if the load fails then we want to stop
434 -- immediately rather than going on to evaluate the expression.
435 when (not (null paths)) $ do
436 ok <- ghciHandle (\e -> do showException e; return Failed) $
438 when (isJust maybe_exprs && failed ok) $
439 io (exitWith (ExitFailure 1))
441 -- if verbosity is greater than 0, or we are connected to a
442 -- terminal, display the prompt in the interactive loop.
443 is_tty <- io (hIsTerminalDevice stdin)
444 dflags <- getDynFlags
445 let show_prompt = verbosity dflags > 0 || is_tty
450 #if defined(mingw32_HOST_OS)
451 -- The win32 Console API mutates the first character of
452 -- type-ahead when reading from it in a non-buffered manner. Work
453 -- around this by flushing the input buffer of type-ahead characters,
454 -- but only if stdin is available.
455 flushed <- io (IO.try (GHC.ConsoleHandler.flushConsole stdin))
457 Left err | isDoesNotExistError err -> return ()
458 | otherwise -> io (ioError err)
459 Right () -> return ()
461 -- enter the interactive loop
462 interactiveLoop is_tty show_prompt
464 -- just evaluate the expression we were given
465 enqueueCommands exprs
466 let handle e = do st <- getGHCiState
467 -- Jump through some hoops to get the
468 -- current progname in the exception text:
469 -- <progname>: <exception>
470 io $ withProgName (progname st)
471 -- this used to be topHandlerFastExit, see #2228
473 runCommands' handle (return Nothing)
476 io $ do when (verbosity dflags > 0) $ putStrLn "Leaving GHCi."
478 interactiveLoop :: Bool -> Bool -> GHCi ()
479 interactiveLoop is_tty show_prompt =
480 -- Ignore ^C exceptions caught here
481 ghciHandleGhcException (\e -> case e of
483 #if defined(mingw32_HOST_OS)
486 interactiveLoop is_tty show_prompt
487 _other -> return ()) $
489 ghciUnblock $ do -- unblock necessary if we recursed from the
490 -- exception handler above.
492 -- read commands from stdin
495 then runCommands readlineLoop
496 else runCommands (fileLoop stdin show_prompt is_tty)
498 runCommands (fileLoop stdin show_prompt is_tty)
502 -- NOTE: We only read .ghci files if they are owned by the current user,
503 -- and aren't world writable. Otherwise, we could be accidentally
504 -- running code planted by a malicious third party.
506 -- Furthermore, We only read ./.ghci if . is owned by the current user
507 -- and isn't writable by anyone else. I think this is sufficient: we
508 -- don't need to check .. and ../.. etc. because "." always refers to
509 -- the same directory while a process is running.
511 checkPerms :: String -> IO Bool
512 #ifdef mingw32_HOST_OS
517 handleIO (\_ -> return False) $ do
518 st <- getFileStatus name
520 if fileOwner st /= me then do
521 putStrLn $ "WARNING: " ++ name ++ " is owned by someone else, IGNORING!"
524 let mode = fileMode st
525 if (groupWriteMode == (mode `intersectFileModes` groupWriteMode))
526 || (otherWriteMode == (mode `intersectFileModes` otherWriteMode))
528 putStrLn $ "*** WARNING: " ++ name ++
529 " is writable by someone else, IGNORING!"
534 fileLoop :: Handle -> Bool -> Bool -> GHCi (Maybe String)
535 fileLoop hdl show_prompt is_tty = do
536 when show_prompt $ do
539 l <- io (IO.try (hGetLine hdl))
541 Left e | isEOFError e -> return Nothing
542 | InvalidArgument <- etype -> return Nothing
543 | otherwise -> io (ioError e)
544 where etype = ioeGetErrorType e
545 -- treat InvalidArgument in the same way as EOF:
546 -- this can happen if the user closed stdin, or
547 -- perhaps did getContents which closes stdin at
550 str <- io $ consoleInputToUnicode is_tty l
553 #ifdef mingw32_HOST_OS
554 -- Convert the console input into Unicode according to the current code page.
555 -- The Windows console stores Unicode characters directly, so this is a
556 -- rather roundabout way of doing things... oh well.
557 -- See #782, #1483, #1649
558 consoleInputToUnicode :: Bool -> String -> IO String
559 consoleInputToUnicode is_tty str
561 cp <- System.Win32.getConsoleCP
562 System.Win32.stringToUnicode cp str
564 decodeStringAsUTF8 str
566 -- for Unix, assume the input is in UTF-8 and decode it to a Unicode String.
568 consoleInputToUnicode :: Bool -> String -> IO String
569 consoleInputToUnicode _is_tty str = decodeStringAsUTF8 str
572 decodeStringAsUTF8 :: String -> IO String
573 decodeStringAsUTF8 str =
574 withCStringLen str $ \(cstr,len) ->
575 utf8DecodeString (castPtr cstr :: Ptr Word8) len
577 mkPrompt :: GHCi String
579 (toplevs,exports) <- GHC.getContext
580 resumes <- GHC.getResumeContext
581 -- st <- getGHCiState
587 let ix = GHC.resumeHistoryIx r
589 then return (brackets (ppr (GHC.resumeSpan r)) <> space)
591 let hist = GHC.resumeHistory r !! (ix-1)
592 span <- GHC.getHistorySpan hist
593 return (brackets (ppr (negate ix) <> char ':'
594 <+> ppr span) <> space)
596 dots | _:rs <- resumes, not (null rs) = text "... "
603 -- let (btoplevs, bexports) = fromMaybe ([],[]) (remembered_ctx st) in
604 -- hsep (map (\m -> text "!*" <> ppr (GHC.moduleName m)) btoplevs) <+>
605 -- hsep (map (\m -> char '!' <> ppr (GHC.moduleName m)) bexports) <+>
606 hsep (map (\m -> char '*' <> ppr (GHC.moduleName m)) toplevs) <+>
607 hsep (map (ppr . GHC.moduleName) exports)
609 deflt_prompt = dots <> context_bit <> modules_bit
611 f ('%':'s':xs) = deflt_prompt <> f xs
612 f ('%':'%':xs) = char '%' <> f xs
613 f (x:xs) = char x <> f xs
617 return (showSDoc (f (prompt st)))
621 readlineLoop :: GHCi (Maybe String)
624 saveSession -- for use by completion
626 l <- io $ withReadline (readline prompt)
629 Nothing -> return Nothing
630 Just "" -> return (Just "") -- Don't put empty lines in the history
633 str <- io $ consoleInputToUnicode True l
636 withReadline :: IO a -> IO a
637 withReadline = bracket_ stopTimer startTimer
638 -- editline doesn't handle some of its system calls returning
639 -- EINTR, so our timer signal confuses it, hence we turn off
640 -- the timer signal when making calls to editline. (#2277)
641 -- If editline is ever fixed, we can remove this.
643 -- These come from the RTS
644 foreign import ccall unsafe startTimer :: IO ()
645 foreign import ccall unsafe stopTimer :: IO ()
648 queryQueue :: GHCi (Maybe String)
653 c:cs -> do setGHCiState st{ cmdqueue = cs }
656 runCommands :: GHCi (Maybe String) -> GHCi ()
657 runCommands = runCommands' handler
659 runCommands' :: (SomeException -> GHCi Bool) -- Exception handler
660 -> GHCi (Maybe String) -> GHCi ()
661 runCommands' eh getCmd = do
662 mb_cmd <- noSpace queryQueue
663 mb_cmd <- maybe (noSpace getCmd) (return . Just) mb_cmd
668 handleSourceError printErrorAndKeepGoing
670 if b then return () else runCommands' eh getCmd
672 printErrorAndKeepGoing err = do
673 GHC.printExceptionAndWarnings err
676 noSpace q = q >>= maybe (return Nothing)
677 (\c->case removeSpaces c of
679 ":{" -> multiLineCmd q
680 c -> return (Just c) )
684 setGHCiState st{ prompt = "%s| " }
685 mb_cmd <- collectCommand q ""
686 getGHCiState >>= \st->setGHCiState st{ prompt = p }
688 -- we can't use removeSpaces for the sublines here, so
689 -- multiline commands are somewhat more brittle against
690 -- fileformat errors (such as \r in dos input on unix),
691 -- we get rid of any extra spaces for the ":}" test;
692 -- we also avoid silent failure if ":}" is not found;
693 -- and since there is no (?) valid occurrence of \r (as
694 -- opposed to its String representation, "\r") inside a
695 -- ghci command, we replace any such with ' ' (argh:-(
696 collectCommand q c = q >>=
697 maybe (io (ioError collectError))
698 (\l->if removeSpaces l == ":}"
699 then return (Just $ removeSpaces c)
700 else collectCommand q (c++map normSpace l))
701 where normSpace '\r' = ' '
703 -- QUESTION: is userError the one to use here?
704 collectError = userError "unterminated multiline command :{ .. :}"
705 doCommand (':' : cmd) = specialCommand cmd
706 doCommand stmt = do timeIt $ runStmt stmt GHC.RunToCompletion
709 enqueueCommands :: [String] -> GHCi ()
710 enqueueCommands cmds = do
712 setGHCiState st{ cmdqueue = cmds ++ cmdqueue st }
715 runStmt :: String -> SingleStep -> GHCi Bool
717 | null (filter (not.isSpace) stmt) = return False
718 | ["import", mod] <- words stmt = keepGoing setContext ('+':mod)
720 = do result <- GhciMonad.runStmt stmt step
721 afterRunStmt (const True) result
723 --afterRunStmt :: GHC.RunResult -> GHCi Bool
724 -- False <=> the statement failed to compile
725 afterRunStmt :: (SrcSpan -> Bool) -> GHC.RunResult -> GHCi Bool
726 afterRunStmt _ (GHC.RunException e) = throw e
727 afterRunStmt step_here run_result = do
728 resumes <- GHC.getResumeContext
730 GHC.RunOk names -> do
731 show_types <- isOptionSet ShowType
732 when show_types $ printTypeOfNames names
733 GHC.RunBreak _ names mb_info
734 | isNothing mb_info ||
735 step_here (GHC.resumeSpan $ head resumes) -> do
736 printForUser $ ptext (sLit "Stopped at") <+>
737 ppr (GHC.resumeSpan $ head resumes)
738 -- printTypeOfNames session names
739 let namesSorted = sortBy compareNames names
740 tythings <- catMaybes `liftM`
741 mapM GHC.lookupName namesSorted
742 docs <- pprTypeAndContents [id | AnId id <- tythings]
743 printForUserPartWay docs
744 maybe (return ()) runBreakCmd mb_info
745 -- run the command set with ":set stop <cmd>"
747 enqueueCommands [stop st]
749 | otherwise -> resume GHC.SingleStep >>=
750 afterRunStmt step_here >> return ()
754 io installSignalHandlers
755 b <- isOptionSet RevertCAFs
758 return (case run_result of GHC.RunOk _ -> True; _ -> False)
760 runBreakCmd :: GHC.BreakInfo -> GHCi ()
761 runBreakCmd info = do
762 let mod = GHC.breakInfo_module info
763 nm = GHC.breakInfo_number info
765 case [ loc | (_,loc) <- breaks st,
766 breakModule loc == mod, breakTick loc == nm ] of
768 loc:_ | null cmd -> return ()
769 | otherwise -> do enqueueCommands [cmd]; return ()
770 where cmd = onBreakCmd loc
772 printTypeOfNames :: [Name] -> GHCi ()
773 printTypeOfNames names
774 = mapM_ (printTypeOfName ) $ sortBy compareNames names
776 compareNames :: Name -> Name -> Ordering
777 n1 `compareNames` n2 = compareWith n1 `compare` compareWith n2
778 where compareWith n = (getOccString n, getSrcSpan n)
780 printTypeOfName :: Name -> GHCi ()
782 = do maybe_tything <- GHC.lookupName n
783 case maybe_tything of
785 Just thing -> printTyThing thing
788 data MaybeCommand = GotCommand Command | BadCommand | NoLastCommand
790 specialCommand :: String -> GHCi Bool
791 specialCommand ('!':str) = shellEscape (dropWhile isSpace str)
792 specialCommand str = do
793 let (cmd,rest) = break isSpace str
794 maybe_cmd <- lookupCommand cmd
796 GotCommand (_,f,_,_) -> f (dropWhile isSpace rest)
798 do io $ hPutStr stdout ("unknown command ':" ++ cmd ++ "'\n"
802 do io $ hPutStr stdout ("there is no last command to perform\n"
806 lookupCommand :: String -> GHCi (MaybeCommand)
807 lookupCommand "" = do
809 case last_command st of
810 Just c -> return $ GotCommand c
811 Nothing -> return NoLastCommand
812 lookupCommand str = do
813 mc <- io $ lookupCommand' str
815 setGHCiState st{ last_command = mc }
817 Just c -> GotCommand c
818 Nothing -> BadCommand
820 lookupCommand' :: String -> IO (Maybe Command)
821 lookupCommand' str = do
822 macros <- readIORef macros_ref
823 let cmds = builtin_commands ++ macros
824 -- look for exact match first, then the first prefix match
825 return $ case [ c | c <- cmds, str == cmdName c ] of
827 [] -> case [ c | c@(s,_,_,_) <- cmds, str `isPrefixOf` s ] of
831 getCurrentBreakSpan :: GHCi (Maybe SrcSpan)
832 getCurrentBreakSpan = do
833 resumes <- GHC.getResumeContext
837 let ix = GHC.resumeHistoryIx r
839 then return (Just (GHC.resumeSpan r))
841 let hist = GHC.resumeHistory r !! (ix-1)
842 span <- GHC.getHistorySpan hist
845 getCurrentBreakModule :: GHCi (Maybe Module)
846 getCurrentBreakModule = do
847 resumes <- GHC.getResumeContext
851 let ix = GHC.resumeHistoryIx r
853 then return (GHC.breakInfo_module `liftM` GHC.resumeBreakInfo r)
855 let hist = GHC.resumeHistory r !! (ix-1)
856 return $ Just $ GHC.getHistoryModule hist
858 -----------------------------------------------------------------------------
861 noArgs :: GHCi () -> String -> GHCi ()
863 noArgs _ _ = io $ putStrLn "This command takes no arguments"
865 help :: String -> GHCi ()
866 help _ = io (putStr helpText)
868 info :: String -> GHCi ()
869 info "" = ghcError (CmdLineError "syntax: ':i <thing-you-want-info-about>'")
870 info s = handleSourceError GHC.printExceptionAndWarnings $ do
871 { let names = words s
872 ; dflags <- getDynFlags
873 ; let pefas = dopt Opt_PrintExplicitForalls dflags
874 ; mapM_ (infoThing pefas) names }
876 infoThing pefas str = do
877 names <- GHC.parseName str
878 mb_stuffs <- mapM GHC.getInfo names
879 let filtered = filterOutChildren (\(t,_f,_i) -> t) (catMaybes mb_stuffs)
880 unqual <- GHC.getPrintUnqual
882 putStrLn (showSDocForUser unqual $
883 vcat (intersperse (text "") $
884 map (pprInfo pefas) filtered))
886 -- Filter out names whose parent is also there Good
887 -- example is '[]', which is both a type and data
888 -- constructor in the same type
889 filterOutChildren :: (a -> TyThing) -> [a] -> [a]
890 filterOutChildren get_thing xs
891 = [x | x <- xs, not (getName (get_thing x) `elemNameSet` implicits)]
893 implicits = mkNameSet [getName t | x <- xs, t <- implicitTyThings (get_thing x)]
895 pprInfo :: PrintExplicitForalls -> (TyThing, Fixity, [GHC.Instance]) -> SDoc
896 pprInfo pefas (thing, fixity, insts)
897 = pprTyThingInContextLoc pefas thing
898 $$ show_fixity fixity
899 $$ vcat (map GHC.pprInstance insts)
902 | fix == GHC.defaultFixity = empty
903 | otherwise = ppr fix <+> ppr (GHC.getName thing)
905 runMain :: String -> GHCi ()
906 runMain s = case toArgs s of
907 Left err -> io (hPutStrLn stderr err)
909 do dflags <- getDynFlags
910 case mainFunIs dflags of
911 Nothing -> doWithArgs args "main"
912 Just f -> doWithArgs args f
914 runRun :: String -> GHCi ()
915 runRun s = case toCmdArgs s of
916 Left err -> io (hPutStrLn stderr err)
917 Right (cmd, args) -> doWithArgs args cmd
919 doWithArgs :: [String] -> String -> GHCi ()
920 doWithArgs args cmd = enqueueCommands ["System.Environment.withArgs " ++
921 show args ++ " (" ++ cmd ++ ")"]
923 addModule :: [FilePath] -> GHCi ()
925 revertCAFs -- always revert CAFs on load/add.
926 files <- mapM expandPath files
927 targets <- mapM (\m -> GHC.guessTarget m Nothing) files
928 -- remove old targets with the same id; e.g. for :add *M
929 mapM_ GHC.removeTarget [ tid | Target tid _ _ <- targets ]
930 mapM_ GHC.addTarget targets
931 prev_context <- GHC.getContext
932 ok <- trySuccess $ GHC.load LoadAllTargets
933 afterLoad ok False prev_context
935 changeDirectory :: String -> GHCi ()
936 changeDirectory "" = do
937 -- :cd on its own changes to the user's home directory
938 either_dir <- io (IO.try getHomeDirectory)
941 Right dir -> changeDirectory dir
942 changeDirectory dir = do
943 graph <- GHC.getModuleGraph
944 when (not (null graph)) $
945 io $ putStr "Warning: changing directory causes all loaded modules to be unloaded,\nbecause the search path has changed.\n"
946 prev_context <- GHC.getContext
948 GHC.load LoadAllTargets
949 setContextAfterLoad prev_context False []
950 GHC.workingDirectoryChanged
951 dir <- expandPath dir
952 io (setCurrentDirectory dir)
954 trySuccess :: GHC.GhcMonad m => m SuccessFlag -> m SuccessFlag
956 handleSourceError (\e -> do GHC.printExceptionAndWarnings e
960 editFile :: String -> GHCi ()
962 do file <- if null str then chooseEditFile else return str
966 $ ghcError (CmdLineError "editor not set, use :set editor")
967 io $ system (cmd ++ ' ':file)
970 -- The user didn't specify a file so we pick one for them.
971 -- Our strategy is to pick the first module that failed to load,
972 -- or otherwise the first target.
974 -- XXX: Can we figure out what happened if the depndecy analysis fails
975 -- (e.g., because the porgrammeer mistyped the name of a module)?
976 -- XXX: Can we figure out the location of an error to pass to the editor?
977 -- XXX: if we could figure out the list of errors that occured during the
978 -- last load/reaload, then we could start the editor focused on the first
980 chooseEditFile :: GHCi String
982 do let hasFailed x = fmap not $ GHC.isLoaded $ GHC.ms_mod_name x
984 graph <- GHC.getModuleGraph
985 failed_graph <- filterM hasFailed graph
986 let order g = flattenSCCs $ GHC.topSortModuleGraph True g Nothing
988 x : _ -> GHC.ml_hs_file (GHC.ms_location x)
991 case pick (order failed_graph) of
992 Just file -> return file
994 do targets <- GHC.getTargets
995 case msum (map fromTarget targets) of
996 Just file -> return file
997 Nothing -> ghcError (CmdLineError "No files to edit.")
999 where fromTarget (GHC.Target (GHC.TargetFile f _) _ _) = Just f
1000 fromTarget _ = Nothing -- when would we get a module target?
1002 defineMacro :: Bool{-overwrite-} -> String -> GHCi ()
1003 defineMacro overwrite s = do
1004 let (macro_name, definition) = break isSpace s
1005 macros <- io (readIORef macros_ref)
1006 let defined = map cmdName macros
1007 if (null macro_name)
1008 then if null defined
1009 then io $ putStrLn "no macros defined"
1010 else io $ putStr ("the following macros are defined:\n" ++
1013 if (not overwrite && macro_name `elem` defined)
1014 then ghcError (CmdLineError
1015 ("macro '" ++ macro_name ++ "' is already defined"))
1018 let filtered = [ cmd | cmd <- macros, cmdName cmd /= macro_name ]
1020 -- give the expression a type signature, so we can be sure we're getting
1021 -- something of the right type.
1022 let new_expr = '(' : definition ++ ") :: String -> IO String"
1024 -- compile the expression
1025 handleSourceError (\e -> GHC.printExceptionAndWarnings e) $ do
1026 hv <- GHC.compileExpr new_expr
1027 io (writeIORef macros_ref --
1028 (filtered ++ [(macro_name, runMacro hv, Nothing, completeNone)]))
1030 runMacro :: GHC.HValue{-String -> IO String-} -> String -> GHCi Bool
1032 str <- io ((unsafeCoerce# fun :: String -> IO String) s)
1033 enqueueCommands (lines str)
1036 undefineMacro :: String -> GHCi ()
1037 undefineMacro str = mapM_ undef (words str)
1038 where undef macro_name = do
1039 cmds <- io (readIORef macros_ref)
1040 if (macro_name `notElem` map cmdName cmds)
1041 then ghcError (CmdLineError
1042 ("macro '" ++ macro_name ++ "' is not defined"))
1044 io (writeIORef macros_ref (filter ((/= macro_name) . cmdName) cmds))
1046 cmdCmd :: String -> GHCi ()
1048 let expr = '(' : str ++ ") :: IO String"
1049 handleSourceError (\e -> GHC.printExceptionAndWarnings e) $ do
1050 hv <- GHC.compileExpr expr
1051 cmds <- io $ (unsafeCoerce# hv :: IO String)
1052 enqueueCommands (lines cmds)
1055 loadModule :: [(FilePath, Maybe Phase)] -> GHCi SuccessFlag
1056 loadModule fs = timeIt (loadModule' fs)
1058 loadModule_ :: [FilePath] -> GHCi ()
1059 loadModule_ fs = do loadModule (zip fs (repeat Nothing)); return ()
1061 loadModule' :: [(FilePath, Maybe Phase)] -> GHCi SuccessFlag
1062 loadModule' files = do
1063 prev_context <- GHC.getContext
1067 discardActiveBreakPoints
1069 GHC.load LoadAllTargets
1072 let (filenames, phases) = unzip files
1073 exp_filenames <- mapM expandPath filenames
1074 let files' = zip exp_filenames phases
1075 targets <- mapM (uncurry GHC.guessTarget) files'
1077 -- NOTE: we used to do the dependency anal first, so that if it
1078 -- fails we didn't throw away the current set of modules. This would
1079 -- require some re-working of the GHC interface, so we'll leave it
1080 -- as a ToDo for now.
1082 GHC.setTargets targets
1083 doLoad False prev_context LoadAllTargets
1085 checkModule :: String -> GHCi ()
1087 let modl = GHC.mkModuleName m
1088 prev_context <- GHC.getContext
1089 ok <- handleSourceError (\e -> GHC.printExceptionAndWarnings e >> return False) $ do
1090 r <- GHC.typecheckModule =<< GHC.parseModule =<< GHC.getModSummary modl
1091 io $ putStrLn (showSDoc (
1092 case GHC.moduleInfo r of
1093 cm | Just scope <- GHC.modInfoTopLevelScope cm ->
1095 (local,global) = ASSERT( all isExternalName scope )
1096 partition ((== modl) . GHC.moduleName . GHC.nameModule) scope
1098 (text "global names: " <+> ppr global) $$
1099 (text "local names: " <+> ppr local)
1102 afterLoad (successIf ok) False prev_context
1104 reloadModule :: String -> GHCi ()
1106 prev_context <- GHC.getContext
1107 doLoad True prev_context $
1108 if null m then LoadAllTargets
1109 else LoadUpTo (GHC.mkModuleName m)
1112 doLoad :: Bool -> ([Module],[Module]) -> LoadHowMuch -> GHCi SuccessFlag
1113 doLoad retain_context prev_context howmuch = do
1114 -- turn off breakpoints before we load: we can't turn them off later, because
1115 -- the ModBreaks will have gone away.
1116 discardActiveBreakPoints
1117 ok <- trySuccess $ GHC.load howmuch
1118 afterLoad ok retain_context prev_context
1121 afterLoad :: SuccessFlag -> Bool -> ([Module],[Module]) -> GHCi ()
1122 afterLoad ok retain_context prev_context = do
1123 revertCAFs -- always revert CAFs on load.
1125 loaded_mod_summaries <- getLoadedModules
1126 let loaded_mods = map GHC.ms_mod loaded_mod_summaries
1127 loaded_mod_names = map GHC.moduleName loaded_mods
1128 modulesLoadedMsg ok loaded_mod_names
1130 setContextAfterLoad prev_context retain_context loaded_mod_summaries
1133 setContextAfterLoad :: ([Module],[Module]) -> Bool -> [GHC.ModSummary] -> GHCi ()
1134 setContextAfterLoad prev keep_ctxt [] = do
1135 prel_mod <- getPrelude
1136 setContextKeepingPackageModules prev keep_ctxt ([], [prel_mod])
1137 setContextAfterLoad prev keep_ctxt ms = do
1138 -- load a target if one is available, otherwise load the topmost module.
1139 targets <- GHC.getTargets
1140 case [ m | Just m <- map (findTarget ms) targets ] of
1142 let graph' = flattenSCCs (GHC.topSortModuleGraph True ms Nothing) in
1143 load_this (last graph')
1148 = case filter (`matches` t) ms of
1152 summary `matches` Target (TargetModule m) _ _
1153 = GHC.ms_mod_name summary == m
1154 summary `matches` Target (TargetFile f _) _ _
1155 | Just f' <- GHC.ml_hs_file (GHC.ms_location summary) = f == f'
1159 load_this summary | m <- GHC.ms_mod summary = do
1160 b <- GHC.moduleIsInterpreted m
1161 if b then setContextKeepingPackageModules prev keep_ctxt ([m], [])
1163 prel_mod <- getPrelude
1164 setContextKeepingPackageModules prev keep_ctxt ([],[prel_mod,m])
1166 -- | Keep any package modules (except Prelude) when changing the context.
1167 setContextKeepingPackageModules
1168 :: ([Module],[Module]) -- previous context
1169 -> Bool -- re-execute :module commands
1170 -> ([Module],[Module]) -- new context
1172 setContextKeepingPackageModules prev_context keep_ctxt (as,bs) = do
1173 let (_,bs0) = prev_context
1174 prel_mod <- getPrelude
1175 let pkg_modules = filter (\p -> not (isHomeModule p) && p /= prel_mod) bs0
1176 let bs1 = if null as then nub (prel_mod : bs) else bs
1177 GHC.setContext as (nub (bs1 ++ pkg_modules))
1181 mapM_ (playCtxtCmd False) (remembered_ctx st)
1184 setGHCiState st{ remembered_ctx = [] }
1186 isHomeModule :: Module -> Bool
1187 isHomeModule mod = GHC.modulePackageId mod == mainPackageId
1189 modulesLoadedMsg :: SuccessFlag -> [ModuleName] -> GHCi ()
1190 modulesLoadedMsg ok mods = do
1191 dflags <- getDynFlags
1192 when (verbosity dflags > 0) $ do
1194 | null mods = text "none."
1195 | otherwise = hsep (
1196 punctuate comma (map ppr mods)) <> text "."
1199 io (putStrLn (showSDoc (text "Failed, modules loaded: " <> mod_commas)))
1201 io (putStrLn (showSDoc (text "Ok, modules loaded: " <> mod_commas)))
1204 typeOfExpr :: String -> GHCi ()
1206 = handleSourceError (\e -> GHC.printExceptionAndWarnings e) $ do
1207 ty <- GHC.exprType str
1208 dflags <- getDynFlags
1209 let pefas = dopt Opt_PrintExplicitForalls dflags
1210 printForUser $ sep [text str, nest 2 (dcolon <+> pprTypeForUser pefas ty)]
1212 kindOfType :: String -> GHCi ()
1214 = handleSourceError (\e -> GHC.printExceptionAndWarnings e) $ do
1215 ty <- GHC.typeKind str
1216 printForUser $ text str <+> dcolon <+> ppr ty
1218 quit :: String -> GHCi Bool
1219 quit _ = return True
1221 shellEscape :: String -> GHCi Bool
1222 shellEscape str = io (system str >> return False)
1224 -----------------------------------------------------------------------------
1225 -- Browsing a module's contents
1227 browseCmd :: Bool -> String -> GHCi ()
1230 ['*':s] | looksLikeModuleName s -> do
1231 m <- wantInterpretedModule s
1232 browseModule bang m False
1233 [s] | looksLikeModuleName s -> do
1235 browseModule bang m True
1237 (as,bs) <- GHC.getContext
1238 -- Guess which module the user wants to browse. Pick
1239 -- modules that are interpreted first. The most
1240 -- recently-added module occurs last, it seems.
1242 (as@(_:_), _) -> browseModule bang (last as) True
1243 ([], bs@(_:_)) -> browseModule bang (last bs) True
1244 ([], []) -> ghcError (CmdLineError ":browse: no current module")
1245 _ -> ghcError (CmdLineError "syntax: :browse <module>")
1247 -- without bang, show items in context of their parents and omit children
1248 -- with bang, show class methods and data constructors separately, and
1249 -- indicate import modules, to aid qualifying unqualified names
1250 -- with sorted, sort items alphabetically
1251 browseModule :: Bool -> Module -> Bool -> GHCi ()
1252 browseModule bang modl exports_only = do
1253 -- :browse! reports qualifiers wrt current context
1254 current_unqual <- GHC.getPrintUnqual
1255 -- Temporarily set the context to the module we're interested in,
1256 -- just so we can get an appropriate PrintUnqualified
1257 (as,bs) <- GHC.getContext
1258 prel_mod <- getPrelude
1259 if exports_only then GHC.setContext [] [prel_mod,modl]
1260 else GHC.setContext [modl] []
1261 target_unqual <- GHC.getPrintUnqual
1262 GHC.setContext as bs
1264 let unqual = if bang then current_unqual else target_unqual
1266 mb_mod_info <- GHC.getModuleInfo modl
1268 Nothing -> ghcError (CmdLineError ("unknown module: " ++
1269 GHC.moduleNameString (GHC.moduleName modl)))
1271 dflags <- getDynFlags
1273 | exports_only = GHC.modInfoExports mod_info
1274 | otherwise = GHC.modInfoTopLevelScope mod_info
1277 -- sort alphabetically name, but putting
1278 -- locally-defined identifiers first.
1279 -- We would like to improve this; see #1799.
1280 sorted_names = loc_sort local ++ occ_sort external
1282 (local,external) = ASSERT( all isExternalName names )
1283 partition ((==modl) . nameModule) names
1284 occ_sort = sortBy (compare `on` nameOccName)
1285 -- try to sort by src location. If the first name in
1286 -- our list has a good source location, then they all should.
1288 | n:_ <- names, isGoodSrcSpan (nameSrcSpan n)
1289 = sortBy (compare `on` nameSrcSpan) names
1293 mb_things <- mapM GHC.lookupName sorted_names
1294 let filtered_things = filterOutChildren (\t -> t) (catMaybes mb_things)
1296 rdr_env <- GHC.getGRE
1298 let pefas = dopt Opt_PrintExplicitForalls dflags
1299 things | bang = catMaybes mb_things
1300 | otherwise = filtered_things
1301 pretty | bang = pprTyThing
1302 | otherwise = pprTyThingInContext
1304 labels [] = text "-- not currently imported"
1305 labels l = text $ intercalate "\n" $ map qualifier l
1306 qualifier = maybe "-- defined locally"
1307 (("-- imported via "++) . intercalate ", "
1308 . map GHC.moduleNameString)
1309 importInfo = RdrName.getGRE_NameQualifier_maybes rdr_env
1310 modNames = map (importInfo . GHC.getName) things
1312 -- annotate groups of imports with their import modules
1313 -- the default ordering is somewhat arbitrary, so we group
1314 -- by header and sort groups; the names themselves should
1315 -- really come in order of source appearance.. (trac #1799)
1316 annotate mts = concatMap (\(m,ts)->labels m:ts)
1317 $ sortBy cmpQualifiers $ group mts
1318 where cmpQualifiers =
1319 compare `on` (map (fmap (map moduleNameFS)) . fst)
1321 group mts@((m,_):_) = (m,map snd g) : group ng
1322 where (g,ng) = partition ((==m).fst) mts
1324 let prettyThings = map (pretty pefas) things
1325 prettyThings' | bang = annotate $ zip modNames prettyThings
1326 | otherwise = prettyThings
1327 io (putStrLn $ showSDocForUser unqual (vcat prettyThings'))
1328 -- ToDo: modInfoInstances currently throws an exception for
1329 -- package modules. When it works, we can do this:
1330 -- $$ vcat (map GHC.pprInstance (GHC.modInfoInstances mod_info))
1332 -----------------------------------------------------------------------------
1333 -- Setting the module context
1335 setContext :: String -> GHCi ()
1337 | all sensible strs = do
1338 playCtxtCmd True (cmd, as, bs)
1340 setGHCiState st{ remembered_ctx = remembered_ctx st ++ [(cmd,as,bs)] }
1341 | otherwise = ghcError (CmdLineError "syntax: :module [+/-] [*]M1 ... [*]Mn")
1343 (cmd, strs, as, bs) =
1345 '+':stuff -> rest AddModules stuff
1346 '-':stuff -> rest RemModules stuff
1347 stuff -> rest SetContext stuff
1349 rest cmd stuff = (cmd, strs, as, bs)
1350 where strs = words stuff
1351 (as,bs) = partitionWith starred strs
1353 sensible ('*':m) = looksLikeModuleName m
1354 sensible m = looksLikeModuleName m
1356 starred ('*':m) = Left m
1359 playCtxtCmd :: Bool -> (CtxtCmd, [String], [String]) -> GHCi ()
1360 playCtxtCmd fail (cmd, as, bs)
1362 (as',bs') <- do_checks fail
1363 (prev_as,prev_bs) <- GHC.getContext
1367 prel_mod <- getPrelude
1368 let bs'' = if null as && prel_mod `notElem` bs' then prel_mod:bs'
1372 let as_to_add = as' \\ (prev_as ++ prev_bs)
1373 bs_to_add = bs' \\ (prev_as ++ prev_bs)
1374 return (prev_as ++ as_to_add, prev_bs ++ bs_to_add)
1376 let new_as = prev_as \\ (as' ++ bs')
1377 new_bs = prev_bs \\ (as' ++ bs')
1378 return (new_as, new_bs)
1379 GHC.setContext new_as new_bs
1382 as' <- mapM wantInterpretedModule as
1383 bs' <- mapM lookupModule bs
1385 do_checks False = do
1386 as' <- mapM (trymaybe . wantInterpretedModule) as
1387 bs' <- mapM (trymaybe . lookupModule) bs
1388 return (catMaybes as', catMaybes bs')
1393 Left _ -> return Nothing
1394 Right a -> return (Just a)
1396 ----------------------------------------------------------------------------
1399 -- set options in the interpreter. Syntax is exactly the same as the
1400 -- ghc command line, except that certain options aren't available (-C,
1403 -- This is pretty fragile: most options won't work as expected. ToDo:
1404 -- figure out which ones & disallow them.
1406 setCmd :: String -> GHCi ()
1408 = do st <- getGHCiState
1409 let opts = options st
1410 io $ putStrLn (showSDoc (
1411 text "options currently set: " <>
1414 else hsep (map (\o -> char '+' <> text (optToStr o)) opts)
1416 dflags <- getDynFlags
1417 io $ putStrLn (showSDoc (
1418 vcat (text "GHCi-specific dynamic flag settings:"
1419 :map (flagSetting dflags) ghciFlags)
1421 io $ putStrLn (showSDoc (
1422 vcat (text "other dynamic, non-language, flag settings:"
1423 :map (flagSetting dflags) nonLanguageDynFlags)
1425 where flagSetting dflags (str, f, _)
1426 | dopt f dflags = text " " <> text "-f" <> text str
1427 | otherwise = text " " <> text "-fno-" <> text str
1428 (ghciFlags,others) = partition (\(_, f, _) -> f `elem` flags)
1430 nonLanguageDynFlags = filterOut (\(_, f, _) -> f `elem` languageOptions)
1432 flags = [Opt_PrintExplicitForalls
1433 ,Opt_PrintBindResult
1434 ,Opt_BreakOnException
1436 ,Opt_PrintEvldWithShow
1439 = case getCmd str of
1440 Right ("args", rest) ->
1442 Left err -> io (hPutStrLn stderr err)
1443 Right args -> setArgs args
1444 Right ("prog", rest) ->
1446 Right [prog] -> setProg prog
1447 _ -> io (hPutStrLn stderr "syntax: :set prog <progname>")
1448 Right ("prompt", rest) -> setPrompt $ dropWhile isSpace rest
1449 Right ("editor", rest) -> setEditor $ dropWhile isSpace rest
1450 Right ("stop", rest) -> setStop $ dropWhile isSpace rest
1451 _ -> case toArgs str of
1452 Left err -> io (hPutStrLn stderr err)
1453 Right wds -> setOptions wds
1455 setArgs, setOptions :: [String] -> GHCi ()
1456 setProg, setEditor, setStop, setPrompt :: String -> GHCi ()
1460 setGHCiState st{ args = args }
1464 setGHCiState st{ progname = prog }
1468 setGHCiState st{ editor = cmd }
1470 setStop str@(c:_) | isDigit c
1471 = do let (nm_str,rest) = break (not.isDigit) str
1474 let old_breaks = breaks st
1475 if all ((/= nm) . fst) old_breaks
1476 then printForUser (text "Breakpoint" <+> ppr nm <+>
1477 text "does not exist")
1479 let new_breaks = map fn old_breaks
1480 fn (i,loc) | i == nm = (i,loc { onBreakCmd = dropWhile isSpace rest })
1481 | otherwise = (i,loc)
1482 setGHCiState st{ breaks = new_breaks }
1485 setGHCiState st{ stop = cmd }
1487 setPrompt value = do
1490 then io $ hPutStrLn stderr $ "syntax: :set prompt <prompt>, currently \"" ++ prompt st ++ "\""
1492 '\"' : _ -> case reads value of
1493 [(value', xs)] | all isSpace xs ->
1494 setGHCiState (st { prompt = value' })
1496 io $ hPutStrLn stderr "Can't parse prompt string. Use Haskell syntax."
1497 _ -> setGHCiState (st { prompt = value })
1500 do -- first, deal with the GHCi opts (+s, +t, etc.)
1501 let (plus_opts, minus_opts) = partitionWith isPlus wds
1502 mapM_ setOpt plus_opts
1503 -- then, dynamic flags
1504 newDynFlags minus_opts
1506 newDynFlags :: [String] -> GHCi ()
1507 newDynFlags minus_opts = do
1508 dflags <- getDynFlags
1509 let pkg_flags = packageFlags dflags
1510 (dflags', leftovers, warns) <- io $ GHC.parseDynamicFlags dflags $ map noLoc minus_opts
1511 handleFlagWarnings dflags' warns
1513 if (not (null leftovers))
1514 then ghcError $ errorsToGhcException leftovers
1517 new_pkgs <- setDynFlags dflags'
1519 -- if the package flags changed, we should reset the context
1520 -- and link the new packages.
1521 dflags <- getDynFlags
1522 when (packageFlags dflags /= pkg_flags) $ do
1523 io $ hPutStrLn stderr "package flags have changed, resetting and loading new packages..."
1525 GHC.load LoadAllTargets
1526 io (linkPackages dflags new_pkgs)
1527 -- package flags changed, we can't re-use any of the old context
1528 setContextAfterLoad ([],[]) False []
1532 unsetOptions :: String -> GHCi ()
1534 = do -- first, deal with the GHCi opts (+s, +t, etc.)
1535 let opts = words str
1536 (minus_opts, rest1) = partition isMinus opts
1537 (plus_opts, rest2) = partitionWith isPlus rest1
1539 if (not (null rest2))
1540 then io (putStrLn ("unknown option: '" ++ head rest2 ++ "'"))
1543 mapM_ unsetOpt plus_opts
1545 let no_flag ('-':'f':rest) = return ("-fno-" ++ rest)
1546 no_flag f = ghcError (ProgramError ("don't know how to reverse " ++ f))
1548 no_flags <- mapM no_flag minus_opts
1549 newDynFlags no_flags
1551 isMinus :: String -> Bool
1552 isMinus ('-':_) = True
1555 isPlus :: String -> Either String String
1556 isPlus ('+':opt) = Left opt
1557 isPlus other = Right other
1559 setOpt, unsetOpt :: String -> GHCi ()
1562 = case strToGHCiOpt str of
1563 Nothing -> io (putStrLn ("unknown option: '" ++ str ++ "'"))
1564 Just o -> setOption o
1567 = case strToGHCiOpt str of
1568 Nothing -> io (putStrLn ("unknown option: '" ++ str ++ "'"))
1569 Just o -> unsetOption o
1571 strToGHCiOpt :: String -> (Maybe GHCiOption)
1572 strToGHCiOpt "s" = Just ShowTiming
1573 strToGHCiOpt "t" = Just ShowType
1574 strToGHCiOpt "r" = Just RevertCAFs
1575 strToGHCiOpt _ = Nothing
1577 optToStr :: GHCiOption -> String
1578 optToStr ShowTiming = "s"
1579 optToStr ShowType = "t"
1580 optToStr RevertCAFs = "r"
1582 -- ---------------------------------------------------------------------------
1585 showCmd :: String -> GHCi ()
1589 ["args"] -> io $ putStrLn (show (args st))
1590 ["prog"] -> io $ putStrLn (show (progname st))
1591 ["prompt"] -> io $ putStrLn (show (prompt st))
1592 ["editor"] -> io $ putStrLn (show (editor st))
1593 ["stop"] -> io $ putStrLn (show (stop st))
1594 ["modules" ] -> showModules
1595 ["bindings"] -> showBindings
1596 ["linker"] -> io showLinkerState
1597 ["breaks"] -> showBkptTable
1598 ["context"] -> showContext
1599 ["packages"] -> showPackages
1600 ["languages"] -> showLanguages
1601 _ -> ghcError (CmdLineError ("syntax: :show [ args | prog | prompt | editor | stop | modules | bindings\n"++
1602 " | breaks | context | packages | languages ]"))
1604 showModules :: GHCi ()
1606 loaded_mods <- getLoadedModules
1607 -- we want *loaded* modules only, see #1734
1608 let show_one ms = do m <- GHC.showModule ms; io (putStrLn m)
1609 mapM_ show_one loaded_mods
1611 getLoadedModules :: GHCi [GHC.ModSummary]
1612 getLoadedModules = do
1613 graph <- GHC.getModuleGraph
1614 filterM (GHC.isLoaded . GHC.ms_mod_name) graph
1616 showBindings :: GHCi ()
1618 bindings <- GHC.getBindings
1619 docs <- pprTypeAndContents
1620 [ id | AnId id <- sortBy compareTyThings bindings]
1621 printForUserPartWay docs
1623 compareTyThings :: TyThing -> TyThing -> Ordering
1624 t1 `compareTyThings` t2 = getName t1 `compareNames` getName t2
1626 printTyThing :: TyThing -> GHCi ()
1627 printTyThing tyth = do dflags <- getDynFlags
1628 let pefas = dopt Opt_PrintExplicitForalls dflags
1629 printForUser (pprTyThing pefas tyth)
1631 showBkptTable :: GHCi ()
1634 printForUser $ prettyLocations (breaks st)
1636 showContext :: GHCi ()
1638 resumes <- GHC.getResumeContext
1639 printForUser $ vcat (map pp_resume (reverse resumes))
1642 ptext (sLit "--> ") <> text (GHC.resumeStmt resume)
1643 $$ nest 2 (ptext (sLit "Stopped at") <+> ppr (GHC.resumeSpan resume))
1645 showPackages :: GHCi ()
1647 pkg_flags <- fmap packageFlags getDynFlags
1648 io $ putStrLn $ showSDoc $ vcat $
1649 text ("active package flags:"++if null pkg_flags then " none" else "")
1650 : map showFlag pkg_flags
1651 pkg_ids <- fmap (preloadPackages . pkgState) getDynFlags
1652 io $ putStrLn $ showSDoc $ vcat $
1653 text "packages currently loaded:"
1654 : map (nest 2 . text . packageIdString)
1655 (sortBy (compare `on` packageIdFS) pkg_ids)
1656 where showFlag (ExposePackage p) = text $ " -package " ++ p
1657 showFlag (HidePackage p) = text $ " -hide-package " ++ p
1658 showFlag (IgnorePackage p) = text $ " -ignore-package " ++ p
1660 showLanguages :: GHCi ()
1662 dflags <- getDynFlags
1663 io $ putStrLn $ showSDoc $ vcat $
1664 text "active language flags:" :
1665 [text (" -X" ++ str) | (str, f, _) <- DynFlags.xFlags, dopt f dflags]
1667 -- -----------------------------------------------------------------------------
1670 completeNone :: String -> IO [String]
1671 completeNone _w = return []
1673 completeMacro, completeIdentifier, completeModule,
1674 completeHomeModule, completeSetOptions, completeShowOptions,
1675 completeFilename, completeHomeModuleOrFile
1676 :: String -> IO [String]
1679 completeWord :: String -> Int -> Int -> IO (Maybe (String, [String]))
1680 completeWord w start end = do
1681 line <- Readline.getLineBuffer
1682 let line_words = words (dropWhile isSpace line)
1684 ':':_ | all isSpace (take (start-1) line) -> wrapCompleter completeCmd w
1686 | ((':':c) : _) <- line_words -> do
1687 completionVars <- lookupCompletionVars c
1688 case completionVars of
1689 (Nothing,complete) -> wrapCompleter complete w
1690 (Just breakChars,complete)
1691 -> let (n,w') = selectWord
1692 (words' (`elem` breakChars) 0 line)
1693 complete' w = do rets <- complete w
1694 return (map (drop n) rets)
1695 in wrapCompleter complete' w'
1696 | ("import" : _) <- line_words ->
1697 wrapCompleter completeModule w
1699 --printf "complete %s, start = %d, end = %d\n" w start end
1700 wrapCompleter completeIdentifier w
1701 where words' _ _ [] = []
1702 words' isBreak n str = let (w,r) = break isBreak str
1703 (s,r') = span isBreak r
1704 in (n,w):words' isBreak (n+length w+length s) r'
1705 -- In a Haskell expression we want to parse 'a-b' as three words
1706 -- where a compiler flag (e.g. -ddump-simpl) should
1707 -- only be a single word.
1708 selectWord [] = (0,w)
1709 selectWord ((offset,x):xs)
1710 | offset+length x >= start = (start-offset,take (end-offset) x)
1711 | otherwise = selectWord xs
1713 lookupCompletionVars ('!':_) = return (Just filenameWordBreakChars,
1715 lookupCompletionVars c = do
1716 maybe_cmd <- lookupCommand' c
1718 Just (_,_,ws,f) -> return (ws,f)
1719 Nothing -> return (Just filenameWordBreakChars,
1723 completeCmd :: String -> IO [String]
1725 cmds <- readIORef macros_ref
1726 return (filter (w `isPrefixOf`) (map (':':)
1727 (map cmdName (builtin_commands ++ cmds))))
1729 completeMacro w = do
1730 cmds <- readIORef macros_ref
1731 return (filter (w `isPrefixOf`) (map cmdName cmds))
1733 completeIdentifier w = do
1734 rdrs <- withRestoredSession GHC.getRdrNamesInScope
1735 return (filter (w `isPrefixOf`) (map (showSDoc.ppr) rdrs))
1737 completeModule w = do
1738 dflags <- withRestoredSession GHC.getSessionDynFlags
1739 let pkg_mods = allExposedModules dflags
1740 return (filter (w `isPrefixOf`) (map (showSDoc.ppr) pkg_mods))
1742 completeHomeModule w = do
1743 g <- withRestoredSession GHC.getModuleGraph
1744 let home_mods = map GHC.ms_mod_name g
1745 return (filter (w `isPrefixOf`) (map (showSDoc.ppr) home_mods))
1747 completeSetOptions w = do
1748 return (filter (w `isPrefixOf`) options)
1749 where options = "args":"prog":"prompt":"editor":"stop":flagList
1750 flagList = map head $ group $ sort allFlags
1752 completeShowOptions w = do
1753 return (filter (w `isPrefixOf`) options)
1754 where options = ["args", "prog", "prompt", "editor", "stop",
1755 "modules", "bindings", "linker", "breaks",
1756 "context", "packages", "languages"]
1758 completeFilename w = do
1759 ws <- Readline.filenameCompletionFunction w
1761 -- If we only found one result, and it's a directory,
1762 -- add a trailing slash.
1764 isDir <- expandPathIO file >>= doesDirectoryExist
1765 if isDir && last file /= '/'
1766 then return [file ++ "/"]
1771 completeHomeModuleOrFile = unionComplete completeHomeModule completeFilename
1773 unionComplete :: (String -> IO [String]) -> (String -> IO [String]) -> String -> IO [String]
1774 unionComplete f1 f2 w = do
1779 wrapCompleter :: (String -> IO [String]) -> String -> IO (Maybe (String,[String]))
1780 wrapCompleter fun w = do
1783 [] -> Readline.setAttemptedCompletionOver True >> return Nothing
1784 [x] -> -- Add a trailing space, unless it already has an appended slash.
1785 let appended = if last x == '/' then x else x ++ " "
1786 in return (Just (appended,[]))
1787 xs -> case getCommonPrefix xs of
1788 "" -> return (Just ("",xs))
1789 pref -> return (Just (pref,xs))
1791 getCommonPrefix :: [String] -> String
1792 getCommonPrefix [] = ""
1793 getCommonPrefix (s:ss) = foldl common s ss
1794 where common _s "" = ""
1796 common (c:cs) (d:ds)
1797 | c == d = c : common cs ds
1800 allExposedModules :: DynFlags -> [ModuleName]
1801 allExposedModules dflags
1802 = concat (map exposedModules (filter exposed (eltsUFM pkg_db)))
1804 pkg_db = pkgIdMap (pkgState dflags)
1806 completeMacro = completeNone
1807 completeIdentifier = completeNone
1808 completeModule = completeNone
1809 completeHomeModule = completeNone
1810 completeSetOptions = completeNone
1811 completeShowOptions = completeNone
1812 completeFilename = completeNone
1813 completeHomeModuleOrFile=completeNone
1816 -- ---------------------------------------------------------------------------
1817 -- User code exception handling
1819 -- This is the exception handler for exceptions generated by the
1820 -- user's code and exceptions coming from children sessions;
1821 -- it normally just prints out the exception. The
1822 -- handler must be recursive, in case showing the exception causes
1823 -- more exceptions to be raised.
1825 -- Bugfix: if the user closed stdout or stderr, the flushing will fail,
1826 -- raising another exception. We therefore don't put the recursive
1827 -- handler arond the flushing operation, so if stderr is closed
1828 -- GHCi will just die gracefully rather than going into an infinite loop.
1829 handler :: SomeException -> GHCi Bool
1831 handler exception = do
1833 io installSignalHandlers
1834 ghciHandle handler (showException exception >> return False)
1836 showException :: SomeException -> GHCi ()
1838 io $ case fromException se of
1839 Just Interrupted -> putStrLn "Interrupted."
1840 -- omit the location for CmdLineError:
1841 Just (CmdLineError s) -> putStrLn s
1843 Just ph@(PhaseFailed {}) -> putStrLn (showGhcException ph "")
1844 Just other_ghc_ex -> print other_ghc_ex
1845 Nothing -> putStrLn ("*** Exception: " ++ show se)
1847 -----------------------------------------------------------------------------
1848 -- recursive exception handlers
1850 -- Don't forget to unblock async exceptions in the handler, or if we're
1851 -- in an exception loop (eg. let a = error a in a) the ^C exception
1852 -- may never be delivered. Thanks to Marcin for pointing out the bug.
1854 ghciHandle :: (SomeException -> GHCi a) -> GHCi a -> GHCi a
1855 ghciHandle h (GHCi m) = GHCi $ \s ->
1857 (\e -> unGHCi (ghciUnblock (h e)) s)
1859 ghciUnblock :: GHCi a -> GHCi a
1860 ghciUnblock (GHCi a) =
1861 GHCi $ \s -> reifyGhc $ \gs ->
1862 Exception.unblock (reflectGhc (a s) gs)
1864 ghciTry :: GHCi a -> GHCi (Either SomeException a)
1865 ghciTry (GHCi m) = GHCi $ \s -> gtry (m s)
1867 -- ----------------------------------------------------------------------------
1870 expandPath :: String -> GHCi String
1871 expandPath path = io (expandPathIO path)
1873 expandPathIO :: String -> IO String
1875 case dropWhile isSpace path of
1877 tilde <- getHomeDirectory -- will fail if HOME not defined
1878 return (tilde ++ '/':d)
1882 wantInterpretedModule :: String -> GHCi Module
1883 wantInterpretedModule str = do
1884 modl <- lookupModule str
1885 dflags <- getDynFlags
1886 when (GHC.modulePackageId modl /= thisPackage dflags) $
1887 ghcError (CmdLineError ("module '" ++ str ++ "' is from another package;\nthis command requires an interpreted module"))
1888 is_interpreted <- GHC.moduleIsInterpreted modl
1889 when (not is_interpreted) $
1890 ghcError (CmdLineError ("module '" ++ str ++ "' is not interpreted; try \':add *" ++ str ++ "' first"))
1893 wantNameFromInterpretedModule :: (Name -> SDoc -> GHCi ()) -> String
1894 -> (Name -> GHCi ())
1896 wantNameFromInterpretedModule noCanDo str and_then =
1897 handleSourceError (GHC.printExceptionAndWarnings) $ do
1898 names <- GHC.parseName str
1902 let modl = ASSERT( isExternalName n ) GHC.nameModule n
1903 if not (GHC.isExternalName n)
1904 then noCanDo n $ ppr n <>
1905 text " is not defined in an interpreted module"
1907 is_interpreted <- GHC.moduleIsInterpreted modl
1908 if not is_interpreted
1909 then noCanDo n $ text "module " <> ppr modl <>
1910 text " is not interpreted"
1913 -- -----------------------------------------------------------------------------
1914 -- commands for debugger
1916 sprintCmd, printCmd, forceCmd :: String -> GHCi ()
1917 sprintCmd = pprintCommand False False
1918 printCmd = pprintCommand True False
1919 forceCmd = pprintCommand False True
1921 pprintCommand :: Bool -> Bool -> String -> GHCi ()
1922 pprintCommand bind force str = do
1923 pprintClosureCommand bind force str
1925 stepCmd :: String -> GHCi ()
1926 stepCmd [] = doContinue (const True) GHC.SingleStep
1927 stepCmd expression = do runStmt expression GHC.SingleStep; return ()
1929 stepLocalCmd :: String -> GHCi ()
1930 stepLocalCmd [] = do
1931 mb_span <- getCurrentBreakSpan
1933 Nothing -> stepCmd []
1935 Just mod <- getCurrentBreakModule
1936 current_toplevel_decl <- enclosingTickSpan mod loc
1937 doContinue (`isSubspanOf` current_toplevel_decl) GHC.SingleStep
1939 stepLocalCmd expression = stepCmd expression
1941 stepModuleCmd :: String -> GHCi ()
1942 stepModuleCmd [] = do
1943 mb_span <- getCurrentBreakSpan
1945 Nothing -> stepCmd []
1947 Just span <- getCurrentBreakSpan
1948 let f some_span = srcSpanFileName_maybe span == srcSpanFileName_maybe some_span
1949 doContinue f GHC.SingleStep
1951 stepModuleCmd expression = stepCmd expression
1953 -- | Returns the span of the largest tick containing the srcspan given
1954 enclosingTickSpan :: Module -> SrcSpan -> GHCi SrcSpan
1955 enclosingTickSpan mod src = do
1956 ticks <- getTickArray mod
1957 let line = srcSpanStartLine src
1958 ASSERT (inRange (bounds ticks) line) do
1959 let enclosing_spans = [ span | (_,span) <- ticks ! line
1960 , srcSpanEnd span >= srcSpanEnd src]
1961 return . head . sortBy leftmost_largest $ enclosing_spans
1963 traceCmd :: String -> GHCi ()
1964 traceCmd [] = doContinue (const True) GHC.RunAndLogSteps
1965 traceCmd expression = do runStmt expression GHC.RunAndLogSteps; return ()
1967 continueCmd :: String -> GHCi ()
1968 continueCmd = noArgs $ doContinue (const True) GHC.RunToCompletion
1970 -- doContinue :: SingleStep -> GHCi ()
1971 doContinue :: (SrcSpan -> Bool) -> SingleStep -> GHCi ()
1972 doContinue pred step = do
1973 runResult <- resume step
1974 afterRunStmt pred runResult
1977 abandonCmd :: String -> GHCi ()
1978 abandonCmd = noArgs $ do
1979 b <- GHC.abandon -- the prompt will change to indicate the new context
1980 when (not b) $ io $ putStrLn "There is no computation running."
1983 deleteCmd :: String -> GHCi ()
1984 deleteCmd argLine = do
1985 deleteSwitch $ words argLine
1987 deleteSwitch :: [String] -> GHCi ()
1989 io $ putStrLn "The delete command requires at least one argument."
1990 -- delete all break points
1991 deleteSwitch ("*":_rest) = discardActiveBreakPoints
1992 deleteSwitch idents = do
1993 mapM_ deleteOneBreak idents
1995 deleteOneBreak :: String -> GHCi ()
1997 | all isDigit str = deleteBreak (read str)
1998 | otherwise = return ()
2000 historyCmd :: String -> GHCi ()
2002 | null arg = history 20
2003 | all isDigit arg = history (read arg)
2004 | otherwise = io $ putStrLn "Syntax: :history [num]"
2007 resumes <- GHC.getResumeContext
2009 [] -> io $ putStrLn "Not stopped at a breakpoint"
2011 let hist = GHC.resumeHistory r
2012 (took,rest) = splitAt num hist
2014 [] -> io $ putStrLn $
2015 "Empty history. Perhaps you forgot to use :trace?"
2017 spans <- mapM GHC.getHistorySpan took
2018 let nums = map (printf "-%-3d:") [(1::Int)..]
2019 names = map GHC.historyEnclosingDecl took
2020 printForUser (vcat(zipWith3
2021 (\x y z -> x <+> y <+> z)
2023 (map (bold . ppr) names)
2024 (map (parens . ppr) spans)))
2025 io $ putStrLn $ if null rest then "<end of history>" else "..."
2027 bold :: SDoc -> SDoc
2028 bold c | do_bold = text start_bold <> c <> text end_bold
2031 backCmd :: String -> GHCi ()
2032 backCmd = noArgs $ do
2033 (names, _, span) <- GHC.back
2034 printForUser $ ptext (sLit "Logged breakpoint at") <+> ppr span
2035 printTypeOfNames names
2036 -- run the command set with ":set stop <cmd>"
2038 enqueueCommands [stop st]
2040 forwardCmd :: String -> GHCi ()
2041 forwardCmd = noArgs $ do
2042 (names, ix, span) <- GHC.forward
2043 printForUser $ (if (ix == 0)
2044 then ptext (sLit "Stopped at")
2045 else ptext (sLit "Logged breakpoint at")) <+> ppr span
2046 printTypeOfNames names
2047 -- run the command set with ":set stop <cmd>"
2049 enqueueCommands [stop st]
2051 -- handle the "break" command
2052 breakCmd :: String -> GHCi ()
2053 breakCmd argLine = do
2054 breakSwitch $ words argLine
2056 breakSwitch :: [String] -> GHCi ()
2058 io $ putStrLn "The break command requires at least one argument."
2059 breakSwitch (arg1:rest)
2060 | looksLikeModuleName arg1 && not (null rest) = do
2061 mod <- wantInterpretedModule arg1
2062 breakByModule mod rest
2063 | all isDigit arg1 = do
2064 (toplevel, _) <- GHC.getContext
2066 (mod : _) -> breakByModuleLine mod (read arg1) rest
2068 io $ putStrLn "Cannot find default module for breakpoint."
2069 io $ putStrLn "Perhaps no modules are loaded for debugging?"
2070 | otherwise = do -- try parsing it as an identifier
2071 wantNameFromInterpretedModule noCanDo arg1 $ \name -> do
2072 let loc = GHC.srcSpanStart (GHC.nameSrcSpan name)
2073 if GHC.isGoodSrcLoc loc
2074 then ASSERT( isExternalName name )
2075 findBreakAndSet (GHC.nameModule name) $
2076 findBreakByCoord (Just (GHC.srcLocFile loc))
2077 (GHC.srcLocLine loc,
2079 else noCanDo name $ text "can't find its location: " <> ppr loc
2081 noCanDo n why = printForUser $
2082 text "cannot set breakpoint on " <> ppr n <> text ": " <> why
2084 breakByModule :: Module -> [String] -> GHCi ()
2085 breakByModule mod (arg1:rest)
2086 | all isDigit arg1 = do -- looks like a line number
2087 breakByModuleLine mod (read arg1) rest
2091 breakByModuleLine :: Module -> Int -> [String] -> GHCi ()
2092 breakByModuleLine mod line args
2093 | [] <- args = findBreakAndSet mod $ findBreakByLine line
2094 | [col] <- args, all isDigit col =
2095 findBreakAndSet mod $ findBreakByCoord Nothing (line, read col)
2096 | otherwise = breakSyntax
2099 breakSyntax = ghcError (CmdLineError "Syntax: :break [<mod>] <line> [<column>]")
2101 findBreakAndSet :: Module -> (TickArray -> Maybe (Int, SrcSpan)) -> GHCi ()
2102 findBreakAndSet mod lookupTickTree = do
2103 tickArray <- getTickArray mod
2104 (breakArray, _) <- getModBreak mod
2105 case lookupTickTree tickArray of
2106 Nothing -> io $ putStrLn $ "No breakpoints found at that location."
2107 Just (tick, span) -> do
2108 success <- io $ setBreakFlag True breakArray tick
2112 recordBreak $ BreakLocation
2119 text "Breakpoint " <> ppr nm <>
2121 then text " was already set at " <> ppr span
2122 else text " activated at " <> ppr span
2124 printForUser $ text "Breakpoint could not be activated at"
2127 -- When a line number is specified, the current policy for choosing
2128 -- the best breakpoint is this:
2129 -- - the leftmost complete subexpression on the specified line, or
2130 -- - the leftmost subexpression starting on the specified line, or
2131 -- - the rightmost subexpression enclosing the specified line
2133 findBreakByLine :: Int -> TickArray -> Maybe (BreakIndex,SrcSpan)
2134 findBreakByLine line arr
2135 | not (inRange (bounds arr) line) = Nothing
2137 listToMaybe (sortBy (leftmost_largest `on` snd) complete) `mplus`
2138 listToMaybe (sortBy (leftmost_smallest `on` snd) incomplete) `mplus`
2139 listToMaybe (sortBy (rightmost `on` snd) ticks)
2143 starts_here = [ tick | tick@(_,span) <- ticks,
2144 GHC.srcSpanStartLine span == line ]
2146 (complete,incomplete) = partition ends_here starts_here
2147 where ends_here (_,span) = GHC.srcSpanEndLine span == line
2149 findBreakByCoord :: Maybe FastString -> (Int,Int) -> TickArray
2150 -> Maybe (BreakIndex,SrcSpan)
2151 findBreakByCoord mb_file (line, col) arr
2152 | not (inRange (bounds arr) line) = Nothing
2154 listToMaybe (sortBy (rightmost `on` snd) contains ++
2155 sortBy (leftmost_smallest `on` snd) after_here)
2159 -- the ticks that span this coordinate
2160 contains = [ tick | tick@(_,span) <- ticks, span `spans` (line,col),
2161 is_correct_file span ]
2163 is_correct_file span
2164 | Just f <- mb_file = GHC.srcSpanFile span == f
2167 after_here = [ tick | tick@(_,span) <- ticks,
2168 GHC.srcSpanStartLine span == line,
2169 GHC.srcSpanStartCol span >= col ]
2171 -- For now, use ANSI bold on terminals that we know support it.
2172 -- Otherwise, we add a line of carets under the active expression instead.
2173 -- In particular, on Windows and when running the testsuite (which sets
2174 -- TERM to vt100 for other reasons) we get carets.
2175 -- We really ought to use a proper termcap/terminfo library.
2177 do_bold = (`isPrefixOf` unsafePerformIO mTerm) `any` ["xterm", "linux"]
2178 where mTerm = System.Environment.getEnv "TERM"
2179 `catchIO` \_ -> return "TERM not set"
2181 start_bold :: String
2182 start_bold = "\ESC[1m"
2184 end_bold = "\ESC[0m"
2186 listCmd :: String -> GHCi ()
2188 mb_span <- getCurrentBreakSpan
2191 printForUser $ text "Not stopped at a breakpoint; nothing to list"
2193 | GHC.isGoodSrcSpan span -> io $ listAround span True
2195 do resumes <- GHC.getResumeContext
2197 [] -> panic "No resumes"
2199 do let traceIt = case GHC.resumeHistory r of
2200 [] -> text "rerunning with :trace,"
2202 doWhat = traceIt <+> text ":back then :list"
2203 printForUser (text "Unable to list source for" <+>
2205 $$ text "Try" <+> doWhat)
2206 listCmd str = list2 (words str)
2208 list2 :: [String] -> GHCi ()
2209 list2 [arg] | all isDigit arg = do
2210 (toplevel, _) <- GHC.getContext
2212 [] -> io $ putStrLn "No module to list"
2213 (mod : _) -> listModuleLine mod (read arg)
2214 list2 [arg1,arg2] | looksLikeModuleName arg1, all isDigit arg2 = do
2215 mod <- wantInterpretedModule arg1
2216 listModuleLine mod (read arg2)
2218 wantNameFromInterpretedModule noCanDo arg $ \name -> do
2219 let loc = GHC.srcSpanStart (GHC.nameSrcSpan name)
2220 if GHC.isGoodSrcLoc loc
2222 tickArray <- ASSERT( isExternalName name )
2223 getTickArray (GHC.nameModule name)
2224 let mb_span = findBreakByCoord (Just (GHC.srcLocFile loc))
2225 (GHC.srcLocLine loc, GHC.srcLocCol loc)
2228 Nothing -> io $ listAround (GHC.srcLocSpan loc) False
2229 Just (_,span) -> io $ listAround span False
2231 noCanDo name $ text "can't find its location: " <>
2234 noCanDo n why = printForUser $
2235 text "cannot list source code for " <> ppr n <> text ": " <> why
2237 io $ putStrLn "syntax: :list [<line> | <module> <line> | <identifier>]"
2239 listModuleLine :: Module -> Int -> GHCi ()
2240 listModuleLine modl line = do
2241 graph <- GHC.getModuleGraph
2242 let this = filter ((== modl) . GHC.ms_mod) graph
2244 [] -> panic "listModuleLine"
2246 let filename = expectJust "listModuleLine" (ml_hs_file (GHC.ms_location summ))
2247 loc = GHC.mkSrcLoc (mkFastString (filename)) line 0
2248 io $ listAround (GHC.srcLocSpan loc) False
2250 -- | list a section of a source file around a particular SrcSpan.
2251 -- If the highlight flag is True, also highlight the span using
2252 -- start_bold\/end_bold.
2253 listAround :: SrcSpan -> Bool -> IO ()
2254 listAround span do_highlight = do
2255 contents <- BS.readFile (unpackFS file)
2257 lines = BS.split '\n' contents
2258 these_lines = take (line2 - line1 + 1 + pad_before + pad_after) $
2259 drop (line1 - 1 - pad_before) $ lines
2260 fst_line = max 1 (line1 - pad_before)
2261 line_nos = [ fst_line .. ]
2263 highlighted | do_highlight = zipWith highlight line_nos these_lines
2264 | otherwise = [\p -> BS.concat[p,l] | l <- these_lines]
2266 bs_line_nos = [ BS.pack (show l ++ " ") | l <- line_nos ]
2267 prefixed = zipWith ($) highlighted bs_line_nos
2269 BS.putStrLn (BS.intercalate (BS.pack "\n") prefixed)
2271 file = GHC.srcSpanFile span
2272 line1 = GHC.srcSpanStartLine span
2273 col1 = GHC.srcSpanStartCol span
2274 line2 = GHC.srcSpanEndLine span
2275 col2 = GHC.srcSpanEndCol span
2277 pad_before | line1 == 1 = 0
2281 highlight | do_bold = highlight_bold
2282 | otherwise = highlight_carets
2284 highlight_bold no line prefix
2285 | no == line1 && no == line2
2286 = let (a,r) = BS.splitAt col1 line
2287 (b,c) = BS.splitAt (col2-col1) r
2289 BS.concat [prefix, a,BS.pack start_bold,b,BS.pack end_bold,c]
2291 = let (a,b) = BS.splitAt col1 line in
2292 BS.concat [prefix, a, BS.pack start_bold, b]
2294 = let (a,b) = BS.splitAt col2 line in
2295 BS.concat [prefix, a, BS.pack end_bold, b]
2296 | otherwise = BS.concat [prefix, line]
2298 highlight_carets no line prefix
2299 | no == line1 && no == line2
2300 = BS.concat [prefix, line, nl, indent, BS.replicate col1 ' ',
2301 BS.replicate (col2-col1) '^']
2303 = BS.concat [indent, BS.replicate (col1 - 2) ' ', BS.pack "vv", nl,
2306 = BS.concat [prefix, line, nl, indent, BS.replicate col2 ' ',
2308 | otherwise = BS.concat [prefix, line]
2310 indent = BS.pack (" " ++ replicate (length (show no)) ' ')
2311 nl = BS.singleton '\n'
2313 -- --------------------------------------------------------------------------
2316 getTickArray :: Module -> GHCi TickArray
2317 getTickArray modl = do
2319 let arrmap = tickarrays st
2320 case lookupModuleEnv arrmap modl of
2321 Just arr -> return arr
2323 (_breakArray, ticks) <- getModBreak modl
2324 let arr = mkTickArray (assocs ticks)
2325 setGHCiState st{tickarrays = extendModuleEnv arrmap modl arr}
2328 discardTickArrays :: GHCi ()
2329 discardTickArrays = do
2331 setGHCiState st{tickarrays = emptyModuleEnv}
2333 mkTickArray :: [(BreakIndex,SrcSpan)] -> TickArray
2335 = accumArray (flip (:)) [] (1, max_line)
2336 [ (line, (nm,span)) | (nm,span) <- ticks,
2337 line <- srcSpanLines span ]
2339 max_line = foldr max 0 (map GHC.srcSpanEndLine (map snd ticks))
2340 srcSpanLines span = [ GHC.srcSpanStartLine span ..
2341 GHC.srcSpanEndLine span ]
2343 lookupModule :: String -> GHCi Module
2344 lookupModule modName
2345 = GHC.findModule (GHC.mkModuleName modName) Nothing
2347 -- don't reset the counter back to zero?
2348 discardActiveBreakPoints :: GHCi ()
2349 discardActiveBreakPoints = do
2351 mapM (turnOffBreak.snd) (breaks st)
2352 setGHCiState $ st { breaks = [] }
2354 deleteBreak :: Int -> GHCi ()
2355 deleteBreak identity = do
2357 let oldLocations = breaks st
2358 (this,rest) = partition (\loc -> fst loc == identity) oldLocations
2360 then printForUser (text "Breakpoint" <+> ppr identity <+>
2361 text "does not exist")
2363 mapM (turnOffBreak.snd) this
2364 setGHCiState $ st { breaks = rest }
2366 turnOffBreak :: BreakLocation -> GHCi Bool
2367 turnOffBreak loc = do
2368 (arr, _) <- getModBreak (breakModule loc)
2369 io $ setBreakFlag False arr (breakTick loc)
2371 getModBreak :: Module -> GHCi (GHC.BreakArray, Array Int SrcSpan)
2372 getModBreak mod = do
2373 Just mod_info <- GHC.getModuleInfo mod
2374 let modBreaks = GHC.modInfoModBreaks mod_info
2375 let array = GHC.modBreaks_flags modBreaks
2376 let ticks = GHC.modBreaks_locs modBreaks
2377 return (array, ticks)
2379 setBreakFlag :: Bool -> GHC.BreakArray -> Int -> IO Bool
2380 setBreakFlag toggle array index
2381 | toggle = GHC.setBreakOn array index
2382 | otherwise = GHC.setBreakOff array index