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 ( Session, LoadHowMuch(..), Target(..), TargetId(..),
25 Module, ModuleName, TyThing(..), Phase,
26 BreakIndex, SrcSpan, Resume, SingleStep )
36 import HscTypes ( implicitTyThings )
37 import qualified RdrName ( getGRE_NameQualifier_maybes ) -- should this come via GHC?
38 import Outputable hiding (printForUser, printForUserPartWay)
39 import Module -- for ModuleEnv
43 -- Other random utilities
46 import BasicTypes hiding (isTopLevel)
47 import Panic hiding (showException)
53 import Maybes ( orElse )
57 #ifndef mingw32_HOST_OS
58 import System.Posix hiding (getEnv)
60 import GHC.ConsoleHandler ( flushConsole )
61 import qualified System.Win32
65 import Control.Concurrent ( yield ) -- Used in readline loop
66 import System.Console.Editline.Readline as Readline
72 -- import Control.Concurrent
74 import System.FilePath
75 import qualified Data.ByteString.Char8 as BS
79 import System.Environment
80 import System.Exit ( exitWith, ExitCode(..) )
81 import System.Directory
83 import System.IO.Error as IO
87 import Control.Monad as Monad
91 import GHC.Exts ( unsafeCoerce# )
92 import GHC.IOBase ( IOErrorType(InvalidArgument) )
95 import Data.IORef ( IORef, readIORef, writeIORef )
98 import System.Posix.Internals ( setNonBlockingFD )
101 -----------------------------------------------------------------------------
103 ghciWelcomeMsg :: String
104 ghciWelcomeMsg = "GHCi, version " ++ cProjectVersion ++
105 ": http://www.haskell.org/ghc/ :? for help"
107 cmdName :: Command -> String
108 cmdName (n,_,_,_) = n
110 GLOBAL_VAR(macros_ref, [], [Command])
112 builtin_commands :: [Command]
114 -- Hugs users are accustomed to :e, so make sure it doesn't overlap
115 ("?", keepGoing help, Nothing, completeNone),
116 ("add", keepGoingPaths addModule, Just filenameWordBreakChars, completeFilename),
117 ("abandon", keepGoing abandonCmd, Nothing, completeNone),
118 ("break", keepGoing breakCmd, Nothing, completeIdentifier),
119 ("back", keepGoing backCmd, Nothing, completeNone),
120 ("browse", keepGoing (browseCmd False), Nothing, completeModule),
121 ("browse!", keepGoing (browseCmd True), Nothing, completeModule),
122 ("cd", keepGoing changeDirectory, Just filenameWordBreakChars, completeFilename),
123 ("check", keepGoing checkModule, Nothing, completeHomeModule),
124 ("continue", keepGoing continueCmd, Nothing, completeNone),
125 ("cmd", keepGoing cmdCmd, Nothing, completeIdentifier),
126 ("ctags", keepGoing createCTagsFileCmd, Just filenameWordBreakChars, completeFilename),
127 ("def", keepGoing (defineMacro False), Nothing, completeIdentifier),
128 ("def!", keepGoing (defineMacro True), Nothing, completeIdentifier),
129 ("delete", keepGoing deleteCmd, Nothing, completeNone),
130 ("e", keepGoing editFile, Just filenameWordBreakChars, completeFilename),
131 ("edit", keepGoing editFile, Just filenameWordBreakChars, completeFilename),
132 ("etags", keepGoing createETagsFileCmd, Just filenameWordBreakChars, completeFilename),
133 ("force", keepGoing forceCmd, Nothing, completeIdentifier),
134 ("forward", keepGoing forwardCmd, Nothing, completeNone),
135 ("help", keepGoing help, Nothing, completeNone),
136 ("history", keepGoing historyCmd, Nothing, completeNone),
137 ("info", keepGoing info, Nothing, completeIdentifier),
138 ("kind", keepGoing kindOfType, Nothing, completeIdentifier),
139 ("load", keepGoingPaths loadModule_, Just filenameWordBreakChars, completeHomeModuleOrFile),
140 ("list", keepGoing listCmd, Nothing, completeNone),
141 ("module", keepGoing setContext, Nothing, completeModule),
142 ("main", keepGoing runMain, Nothing, completeIdentifier),
143 ("print", keepGoing printCmd, Nothing, completeIdentifier),
144 ("quit", quit, Nothing, completeNone),
145 ("reload", keepGoing reloadModule, Nothing, completeNone),
146 ("run", keepGoing runRun, Nothing, completeIdentifier),
147 ("set", keepGoing setCmd, Just flagWordBreakChars, completeSetOptions),
148 ("show", keepGoing showCmd, Nothing, completeNone),
149 ("sprint", keepGoing sprintCmd, Nothing, completeIdentifier),
150 ("step", keepGoing stepCmd, Nothing, completeIdentifier),
151 ("steplocal", keepGoing stepLocalCmd, Nothing, completeIdentifier),
152 ("stepmodule",keepGoing stepModuleCmd, Nothing, completeIdentifier),
153 ("type", keepGoing typeOfExpr, Nothing, completeIdentifier),
154 ("trace", keepGoing traceCmd, Nothing, completeIdentifier),
155 ("undef", keepGoing undefineMacro, Nothing, completeMacro),
156 ("unset", keepGoing unsetOptions, Just flagWordBreakChars, completeSetOptions)
160 -- We initialize readline (in the interactiveUI function) to use
161 -- word_break_chars as the default set of completion word break characters.
162 -- This can be overridden for a particular command (for example, filename
163 -- expansion shouldn't consider '/' to be a word break) by setting the third
164 -- entry in the Command tuple above.
166 -- NOTE: in order for us to override the default correctly, any custom entry
167 -- must be a SUBSET of word_break_chars.
169 word_break_chars :: String
170 word_break_chars = let symbols = "!#$%&*+/<=>?@\\^|-~"
171 specials = "(),;[]`{}"
173 in spaces ++ specials ++ symbols
176 flagWordBreakChars, filenameWordBreakChars :: String
177 flagWordBreakChars = " \t\n"
178 filenameWordBreakChars = " \t\n\\`@$><=;|&{(" -- bash defaults
181 keepGoing :: (String -> GHCi ()) -> (String -> GHCi Bool)
182 keepGoing a str = a str >> return False
184 keepGoingPaths :: ([FilePath] -> GHCi ()) -> (String -> GHCi Bool)
186 = do case toArgs str of
187 Left err -> io (hPutStrLn stderr err)
191 shortHelpText :: String
192 shortHelpText = "use :? for help.\n"
196 " Commands available from the prompt:\n" ++
198 " <statement> evaluate/run <statement>\n" ++
199 " : repeat last command\n" ++
200 " :{\\n ..lines.. \\n:}\\n multiline command\n" ++
201 " :add <filename> ... add module(s) to the current target set\n" ++
202 " :browse[!] [[*]<mod>] display the names defined by module <mod>\n" ++
203 " (!: more details; *: all top-level names)\n" ++
204 " :cd <dir> change directory to <dir>\n" ++
205 " :cmd <expr> run the commands returned by <expr>::IO String\n" ++
206 " :ctags [<file>] create tags file for Vi (default: \"tags\")\n" ++
207 " :def <cmd> <expr> define a command :<cmd>\n" ++
208 " :edit <file> edit file\n" ++
209 " :edit edit last module\n" ++
210 " :etags [<file>] create tags file for Emacs (default: \"TAGS\")\n" ++
211 " :help, :? display this list of commands\n" ++
212 " :info [<name> ...] display information about the given names\n" ++
213 " :kind <type> show the kind of <type>\n" ++
214 " :load <filename> ... load module(s) and their dependents\n" ++
215 " :main [<arguments> ...] run the main function with the given arguments\n" ++
216 " :module [+/-] [*]<mod> ... set the context for expression evaluation\n" ++
217 " :quit exit GHCi\n" ++
218 " :reload reload the current module set\n" ++
219 " :run function [<arguments> ...] run the function with the given arguments\n" ++
220 " :type <expr> show the type of <expr>\n" ++
221 " :undef <cmd> undefine user-defined command :<cmd>\n" ++
222 " :!<command> run the shell command <command>\n" ++
224 " -- Commands for debugging:\n" ++
226 " :abandon at a breakpoint, abandon current computation\n" ++
227 " :back go back in the history (after :trace)\n" ++
228 " :break [<mod>] <l> [<col>] set a breakpoint at the specified location\n" ++
229 " :break <name> set a breakpoint on the specified function\n" ++
230 " :continue resume after a breakpoint\n" ++
231 " :delete <number> delete the specified breakpoint\n" ++
232 " :delete * delete all breakpoints\n" ++
233 " :force <expr> print <expr>, forcing unevaluated parts\n" ++
234 " :forward go forward in the history (after :back)\n" ++
235 " :history [<n>] after :trace, show the execution history\n" ++
236 " :list show the source code around current breakpoint\n" ++
237 " :list identifier show the source code for <identifier>\n" ++
238 " :list [<module>] <line> show the source code around line number <line>\n" ++
239 " :print [<name> ...] prints a value without forcing its computation\n" ++
240 " :sprint [<name> ...] simplifed version of :print\n" ++
241 " :step single-step after stopping at a breakpoint\n"++
242 " :step <expr> single-step into <expr>\n"++
243 " :steplocal single-step within the current top-level binding\n"++
244 " :stepmodule single-step restricted to the current module\n"++
245 " :trace trace after stopping at a breakpoint\n"++
246 " :trace <expr> evaluate <expr> with tracing on (see :history)\n"++
249 " -- Commands for changing settings:\n" ++
251 " :set <option> ... set options\n" ++
252 " :set args <arg> ... set the arguments returned by System.getArgs\n" ++
253 " :set prog <progname> set the value returned by System.getProgName\n" ++
254 " :set prompt <prompt> set the prompt used in GHCi\n" ++
255 " :set editor <cmd> set the command used for :edit\n" ++
256 " :set stop <cmd> set the command to run when a breakpoint is hit\n" ++
257 " :unset <option> ... unset options\n" ++
259 " Options for ':set' and ':unset':\n" ++
261 " +r revert top-level expressions after each evaluation\n" ++
262 " +s print timing/memory stats after each evaluation\n" ++
263 " +t print type after evaluation\n" ++
264 " -<flags> most GHC command line flags can also be set here\n" ++
265 " (eg. -v2, -fglasgow-exts, etc.)\n" ++
266 " for GHCi-specific flags, see User's Guide,\n"++
267 " Flag reference, Interactive-mode options\n" ++
269 " -- Commands for displaying information:\n" ++
271 " :show bindings show the current bindings made at the prompt\n" ++
272 " :show breaks show the active breakpoints\n" ++
273 " :show context show the breakpoint context\n" ++
274 " :show modules show the currently loaded modules\n" ++
275 " :show packages show the currently active package flags\n" ++
276 " :show languages show the currently active language flags\n" ++
277 " :show <setting> show value of <setting>, which is one of\n" ++
278 " [args, prog, prompt, editor, stop]\n" ++
281 findEditor :: IO String
286 win <- System.Win32.getWindowsDirectory
287 return (win </> "notepad.exe")
292 interactiveUI :: Session -> [(FilePath, Maybe Phase)] -> Maybe [String]
294 interactiveUI session srcs maybe_exprs = do
295 -- HACK! If we happen to get into an infinite loop (eg the user
296 -- types 'let x=x in x' at the prompt), then the thread will block
297 -- on a blackhole, and become unreachable during GC. The GC will
298 -- detect that it is unreachable and send it the NonTermination
299 -- exception. However, since the thread is unreachable, everything
300 -- it refers to might be finalized, including the standard Handles.
301 -- This sounds like a bug, but we don't have a good solution right
307 -- Initialise buffering for the *interpreted* I/O system
308 initInterpBuffering session
310 when (isNothing maybe_exprs) $ do
311 -- Only for GHCi (not runghc and ghc -e):
313 -- Turn buffering off for the compiled program's stdout/stderr
315 -- Turn buffering off for GHCi's stdout
317 hSetBuffering stdout NoBuffering
318 -- We don't want the cmd line to buffer any input that might be
319 -- intended for the program, so unbuffer stdin.
320 hSetBuffering stdin NoBuffering
323 is_tty <- hIsTerminalDevice stdin
324 when is_tty $ withReadline $ do
328 (\dir -> Readline.readHistory (dir </> "ghci_history"))
331 Readline.setAttemptedCompletionFunction (Just completeWord)
332 --Readline.parseAndBind "set show-all-if-ambiguous 1"
334 Readline.setBasicWordBreakCharacters word_break_chars
335 Readline.setCompleterWordBreakCharacters word_break_chars
336 Readline.setCompletionAppendCharacter Nothing
339 -- initial context is just the Prelude
340 prel_mod <- GHC.findModule session (GHC.mkModuleName "Prelude")
342 GHC.setContext session [] [prel_mod]
344 default_editor <- findEditor
346 cwd <- getCurrentDirectory
348 startGHCi (runGHCi srcs maybe_exprs)
349 GHCiState{ progname = "<interactive>",
353 editor = default_editor,
359 tickarrays = emptyModuleEnv,
360 last_command = Nothing,
364 ghc_e = isJust maybe_exprs
368 Readline.stifleHistory 100
369 withGhcAppData (\dir -> Readline.writeHistory (dir </> "ghci_history"))
371 Readline.resetTerminal Nothing
376 withGhcAppData :: (FilePath -> IO a) -> IO a -> IO a
377 withGhcAppData right left = do
378 either_dir <- IO.try (getAppUserDataDirectory "ghc")
380 Right dir -> right dir
384 runGHCi :: [(FilePath, Maybe Phase)] -> Maybe [String] -> GHCi ()
385 runGHCi paths maybe_exprs = do
387 read_dot_files = not opt_IgnoreDotGhci
389 current_dir = return (Just ".ghci")
391 app_user_dir = io $ withGhcAppData
392 (\dir -> return (Just (dir </> "ghci.conf")))
396 either_dir <- io $ IO.try (getEnv "HOME")
398 Right home -> return (Just (home </> ".ghci"))
401 sourceConfigFile :: FilePath -> GHCi ()
402 sourceConfigFile file = do
403 exists <- io $ doesFileExist file
405 dir_ok <- io $ checkPerms (getDirectory file)
406 file_ok <- io $ checkPerms file
407 when (dir_ok && file_ok) $ do
408 either_hdl <- io $ IO.try (openFile file ReadMode)
411 Right hdl -> runCommands (fileLoop hdl False False)
413 getDirectory f = case takeDirectory f of "" -> "."; d -> d
415 when (read_dot_files) $ do
416 cfgs0 <- sequence [ current_dir, app_user_dir, home_dir ]
417 cfgs <- io $ mapM canonicalizePath (catMaybes cfgs0)
418 mapM_ sourceConfigFile (nub cfgs)
419 -- nub, because we don't want to read .ghci twice if the
422 -- Perform a :load for files given on the GHCi command line
423 -- When in -e mode, if the load fails then we want to stop
424 -- immediately rather than going on to evaluate the expression.
425 when (not (null paths)) $ do
426 ok <- ghciHandle (\e -> do showException e; return Failed) $
428 when (isJust maybe_exprs && failed ok) $
429 io (exitWith (ExitFailure 1))
431 -- if verbosity is greater than 0, or we are connected to a
432 -- terminal, display the prompt in the interactive loop.
433 is_tty <- io (hIsTerminalDevice stdin)
434 dflags <- getDynFlags
435 let show_prompt = verbosity dflags > 0 || is_tty
440 #if defined(mingw32_HOST_OS)
441 -- The win32 Console API mutates the first character of
442 -- type-ahead when reading from it in a non-buffered manner. Work
443 -- around this by flushing the input buffer of type-ahead characters,
444 -- but only if stdin is available.
445 flushed <- io (IO.try (GHC.ConsoleHandler.flushConsole stdin))
447 Left err | isDoesNotExistError err -> return ()
448 | otherwise -> io (ioError err)
449 Right () -> return ()
451 -- enter the interactive loop
452 interactiveLoop is_tty show_prompt
454 -- just evaluate the expression we were given
455 enqueueCommands exprs
456 let handle e = do st <- getGHCiState
457 -- Jump through some hoops to get the
458 -- current progname in the exception text:
459 -- <progname>: <exception>
460 io $ withProgName (progname st)
461 -- this used to be topHandlerFastExit, see #2228
463 runCommands' handle (return Nothing)
466 io $ do when (verbosity dflags > 0) $ putStrLn "Leaving GHCi."
468 interactiveLoop :: Bool -> Bool -> GHCi ()
469 interactiveLoop is_tty show_prompt =
470 -- Ignore ^C exceptions caught here
471 ghciHandleGhcException (\e -> case e of
473 #if defined(mingw32_HOST_OS)
476 interactiveLoop is_tty show_prompt
477 _other -> return ()) $
479 ghciUnblock $ do -- unblock necessary if we recursed from the
480 -- exception handler above.
482 -- read commands from stdin
485 then runCommands readlineLoop
486 else runCommands (fileLoop stdin show_prompt is_tty)
488 runCommands (fileLoop stdin show_prompt is_tty)
492 -- NOTE: We only read .ghci files if they are owned by the current user,
493 -- and aren't world writable. Otherwise, we could be accidentally
494 -- running code planted by a malicious third party.
496 -- Furthermore, We only read ./.ghci if . is owned by the current user
497 -- and isn't writable by anyone else. I think this is sufficient: we
498 -- don't need to check .. and ../.. etc. because "." always refers to
499 -- the same directory while a process is running.
501 checkPerms :: String -> IO Bool
502 #ifdef mingw32_HOST_OS
507 handleIO (\_ -> return False) $ do
508 st <- getFileStatus name
510 if fileOwner st /= me then do
511 putStrLn $ "WARNING: " ++ name ++ " is owned by someone else, IGNORING!"
514 let mode = fileMode st
515 if (groupWriteMode == (mode `intersectFileModes` groupWriteMode))
516 || (otherWriteMode == (mode `intersectFileModes` otherWriteMode))
518 putStrLn $ "*** WARNING: " ++ name ++
519 " is writable by someone else, IGNORING!"
524 fileLoop :: Handle -> Bool -> Bool -> GHCi (Maybe String)
525 fileLoop hdl show_prompt is_tty = do
526 when show_prompt $ do
529 l <- io (IO.try (hGetLine hdl))
531 Left e | isEOFError e -> return Nothing
532 | InvalidArgument <- etype -> return Nothing
533 | otherwise -> io (ioError e)
534 where etype = ioeGetErrorType e
535 -- treat InvalidArgument in the same way as EOF:
536 -- this can happen if the user closed stdin, or
537 -- perhaps did getContents which closes stdin at
540 str <- io $ consoleInputToUnicode is_tty l
543 #ifdef mingw32_HOST_OS
544 -- Convert the console input into Unicode according to the current code page.
545 -- The Windows console stores Unicode characters directly, so this is a
546 -- rather roundabout way of doing things... oh well.
547 -- See #782, #1483, #1649
548 consoleInputToUnicode :: Bool -> String -> IO String
549 consoleInputToUnicode is_tty str
551 cp <- System.Win32.getConsoleCP
552 System.Win32.stringToUnicode cp str
554 decodeStringAsUTF8 str
556 -- for Unix, assume the input is in UTF-8 and decode it to a Unicode String.
558 consoleInputToUnicode :: Bool -> String -> IO String
559 consoleInputToUnicode _is_tty str = decodeStringAsUTF8 str
562 decodeStringAsUTF8 :: String -> IO String
563 decodeStringAsUTF8 str =
564 withCStringLen str $ \(cstr,len) ->
565 utf8DecodeString (castPtr cstr :: Ptr Word8) len
567 mkPrompt :: GHCi String
569 session <- getSession
570 (toplevs,exports) <- io (GHC.getContext session)
571 resumes <- io $ GHC.getResumeContext session
572 -- st <- getGHCiState
578 let ix = GHC.resumeHistoryIx r
580 then return (brackets (ppr (GHC.resumeSpan r)) <> space)
582 let hist = GHC.resumeHistory r !! (ix-1)
583 span <- io$ GHC.getHistorySpan session hist
584 return (brackets (ppr (negate ix) <> char ':'
585 <+> ppr span) <> space)
587 dots | _:rs <- resumes, not (null rs) = text "... "
594 -- let (btoplevs, bexports) = fromMaybe ([],[]) (remembered_ctx st) in
595 -- hsep (map (\m -> text "!*" <> ppr (GHC.moduleName m)) btoplevs) <+>
596 -- hsep (map (\m -> char '!' <> ppr (GHC.moduleName m)) bexports) <+>
597 hsep (map (\m -> char '*' <> ppr (GHC.moduleName m)) toplevs) <+>
598 hsep (map (ppr . GHC.moduleName) exports)
600 deflt_prompt = dots <> context_bit <> modules_bit
602 f ('%':'s':xs) = deflt_prompt <> f xs
603 f ('%':'%':xs) = char '%' <> f xs
604 f (x:xs) = char x <> f xs
608 return (showSDoc (f (prompt st)))
612 readlineLoop :: GHCi (Maybe String)
615 saveSession -- for use by completion
617 l <- io $ withReadline (readline prompt)
620 Nothing -> return Nothing
621 Just "" -> return (Just "") -- Don't put empty lines in the history
624 str <- io $ consoleInputToUnicode True l
627 withReadline :: IO a -> IO a
628 withReadline = bracket_ stopTimer (do startTimer; setNonBlockingFD 0)
629 -- Two problems are being worked around here:
630 -- 1. readline sometimes puts stdin into blocking mode,
631 -- so we need to put it back for the IO library
632 -- 2. editline doesn't handle some of its system calls returning
633 -- EINTR, so our timer signal confuses it, hence we turn off
634 -- the timer signal when making calls to editline. (#2277)
635 -- If editline is ever fixed, we can remove this.
637 -- These come from the RTS
638 foreign import ccall unsafe startTimer :: IO ()
639 foreign import ccall unsafe stopTimer :: IO ()
642 queryQueue :: GHCi (Maybe String)
647 c:cs -> do setGHCiState st{ cmdqueue = cs }
650 runCommands :: GHCi (Maybe String) -> GHCi ()
651 runCommands = runCommands' handler
653 runCommands' :: (SomeException -> GHCi Bool) -- Exception handler
654 -> GHCi (Maybe String) -> GHCi ()
655 runCommands' eh getCmd = do
656 mb_cmd <- noSpace queryQueue
657 mb_cmd <- maybe (noSpace getCmd) (return . Just) mb_cmd
661 b <- ghciHandle eh (doCommand c)
662 if b then return () else runCommands' eh getCmd
664 noSpace q = q >>= maybe (return Nothing)
665 (\c->case removeSpaces c of
667 ":{" -> multiLineCmd q
668 c -> return (Just c) )
672 setGHCiState st{ prompt = "%s| " }
673 mb_cmd <- collectCommand q ""
674 getGHCiState >>= \st->setGHCiState st{ prompt = p }
676 -- we can't use removeSpaces for the sublines here, so
677 -- multiline commands are somewhat more brittle against
678 -- fileformat errors (such as \r in dos input on unix),
679 -- we get rid of any extra spaces for the ":}" test;
680 -- we also avoid silent failure if ":}" is not found;
681 -- and since there is no (?) valid occurrence of \r (as
682 -- opposed to its String representation, "\r") inside a
683 -- ghci command, we replace any such with ' ' (argh:-(
684 collectCommand q c = q >>=
685 maybe (io (ioError collectError))
686 (\l->if removeSpaces l == ":}"
687 then return (Just $ removeSpaces c)
688 else collectCommand q (c++map normSpace l))
689 where normSpace '\r' = ' '
691 -- QUESTION: is userError the one to use here?
692 collectError = userError "unterminated multiline command :{ .. :}"
693 doCommand (':' : cmd) = specialCommand cmd
694 doCommand stmt = do timeIt $ runStmt stmt GHC.RunToCompletion
697 enqueueCommands :: [String] -> GHCi ()
698 enqueueCommands cmds = do
700 setGHCiState st{ cmdqueue = cmds ++ cmdqueue st }
703 runStmt :: String -> SingleStep -> GHCi Bool
705 | null (filter (not.isSpace) stmt) = return False
706 | ["import", mod] <- words stmt = keepGoing setContext ('+':mod)
708 = do result <- GhciMonad.runStmt stmt step
709 afterRunStmt (const True) result
711 --afterRunStmt :: GHC.RunResult -> GHCi Bool
712 -- False <=> the statement failed to compile
713 afterRunStmt :: (SrcSpan -> Bool) -> GHC.RunResult -> GHCi Bool
714 afterRunStmt _ (GHC.RunException e) = throw e
715 afterRunStmt step_here run_result = do
716 session <- getSession
717 resumes <- io $ GHC.getResumeContext session
719 GHC.RunOk names -> do
720 show_types <- isOptionSet ShowType
721 when show_types $ printTypeOfNames session names
722 GHC.RunBreak _ names mb_info
723 | isNothing mb_info ||
724 step_here (GHC.resumeSpan $ head resumes) -> do
725 printForUser $ ptext (sLit "Stopped at") <+>
726 ppr (GHC.resumeSpan $ head resumes)
727 -- printTypeOfNames session names
728 let namesSorted = sortBy compareNames names
729 tythings <- catMaybes `liftM`
730 io (mapM (GHC.lookupName session) namesSorted)
731 docs <- io$ pprTypeAndContents session [id | AnId id <- tythings]
732 printForUserPartWay docs
733 maybe (return ()) runBreakCmd mb_info
734 -- run the command set with ":set stop <cmd>"
736 enqueueCommands [stop st]
738 | otherwise -> resume GHC.SingleStep >>=
739 afterRunStmt step_here >> return ()
743 io installSignalHandlers
744 b <- isOptionSet RevertCAFs
747 return (case run_result of GHC.RunOk _ -> True; _ -> False)
749 runBreakCmd :: GHC.BreakInfo -> GHCi ()
750 runBreakCmd info = do
751 let mod = GHC.breakInfo_module info
752 nm = GHC.breakInfo_number info
754 case [ loc | (_,loc) <- breaks st,
755 breakModule loc == mod, breakTick loc == nm ] of
757 loc:_ | null cmd -> return ()
758 | otherwise -> do enqueueCommands [cmd]; return ()
759 where cmd = onBreakCmd loc
761 printTypeOfNames :: Session -> [Name] -> GHCi ()
762 printTypeOfNames session names
763 = mapM_ (printTypeOfName session) $ sortBy compareNames names
765 compareNames :: Name -> Name -> Ordering
766 n1 `compareNames` n2 = compareWith n1 `compare` compareWith n2
767 where compareWith n = (getOccString n, getSrcSpan n)
769 printTypeOfName :: Session -> Name -> GHCi ()
770 printTypeOfName session n
771 = do maybe_tything <- io (GHC.lookupName session n)
772 case maybe_tything of
774 Just thing -> printTyThing thing
777 data MaybeCommand = GotCommand Command | BadCommand | NoLastCommand
779 specialCommand :: String -> GHCi Bool
780 specialCommand ('!':str) = shellEscape (dropWhile isSpace str)
781 specialCommand str = do
782 let (cmd,rest) = break isSpace str
783 maybe_cmd <- lookupCommand cmd
785 GotCommand (_,f,_,_) -> f (dropWhile isSpace rest)
787 do io $ hPutStr stdout ("unknown command ':" ++ cmd ++ "'\n"
791 do io $ hPutStr stdout ("there is no last command to perform\n"
795 lookupCommand :: String -> GHCi (MaybeCommand)
796 lookupCommand "" = do
798 case last_command st of
799 Just c -> return $ GotCommand c
800 Nothing -> return NoLastCommand
801 lookupCommand str = do
802 mc <- io $ lookupCommand' str
804 setGHCiState st{ last_command = mc }
806 Just c -> GotCommand c
807 Nothing -> BadCommand
809 lookupCommand' :: String -> IO (Maybe Command)
810 lookupCommand' str = do
811 macros <- readIORef macros_ref
812 let cmds = builtin_commands ++ macros
813 -- look for exact match first, then the first prefix match
814 return $ case [ c | c <- cmds, str == cmdName c ] of
816 [] -> case [ c | c@(s,_,_,_) <- cmds, str `isPrefixOf` s ] of
820 getCurrentBreakSpan :: GHCi (Maybe SrcSpan)
821 getCurrentBreakSpan = do
822 session <- getSession
823 resumes <- io $ GHC.getResumeContext session
827 let ix = GHC.resumeHistoryIx r
829 then return (Just (GHC.resumeSpan r))
831 let hist = GHC.resumeHistory r !! (ix-1)
832 span <- io $ GHC.getHistorySpan session hist
835 getCurrentBreakModule :: GHCi (Maybe Module)
836 getCurrentBreakModule = do
837 session <- getSession
838 resumes <- io $ GHC.getResumeContext session
842 let ix = GHC.resumeHistoryIx r
844 then return (GHC.breakInfo_module `liftM` GHC.resumeBreakInfo r)
846 let hist = GHC.resumeHistory r !! (ix-1)
847 return $ Just $ GHC.getHistoryModule hist
849 -----------------------------------------------------------------------------
852 noArgs :: GHCi () -> String -> GHCi ()
854 noArgs _ _ = io $ putStrLn "This command takes no arguments"
856 help :: String -> GHCi ()
857 help _ = io (putStr helpText)
859 info :: String -> GHCi ()
860 info "" = ghcError (CmdLineError "syntax: ':i <thing-you-want-info-about>'")
861 info s = do { let names = words s
862 ; session <- getSession
863 ; dflags <- getDynFlags
864 ; let pefas = dopt Opt_PrintExplicitForalls dflags
865 ; mapM_ (infoThing pefas session) names }
867 infoThing pefas session str = io $ do
868 names <- GHC.parseName session str
869 mb_stuffs <- mapM (GHC.getInfo session) names
870 let filtered = filterOutChildren (\(t,_f,_i) -> t) (catMaybes mb_stuffs)
871 unqual <- GHC.getPrintUnqual session
872 putStrLn (showSDocForUser unqual $
873 vcat (intersperse (text "") $
874 map (pprInfo pefas) filtered))
876 -- Filter out names whose parent is also there Good
877 -- example is '[]', which is both a type and data
878 -- constructor in the same type
879 filterOutChildren :: (a -> TyThing) -> [a] -> [a]
880 filterOutChildren get_thing xs
881 = [x | x <- xs, not (getName (get_thing x) `elemNameSet` implicits)]
883 implicits = mkNameSet [getName t | x <- xs, t <- implicitTyThings (get_thing x)]
885 pprInfo :: PrintExplicitForalls -> (TyThing, Fixity, [GHC.Instance]) -> SDoc
886 pprInfo pefas (thing, fixity, insts)
887 = pprTyThingInContextLoc pefas thing
888 $$ show_fixity fixity
889 $$ vcat (map GHC.pprInstance insts)
892 | fix == GHC.defaultFixity = empty
893 | otherwise = ppr fix <+> ppr (GHC.getName thing)
895 runMain :: String -> GHCi ()
896 runMain s = case toArgs s of
897 Left err -> io (hPutStrLn stderr err)
899 do dflags <- getDynFlags
900 case mainFunIs dflags of
901 Nothing -> doWithArgs args "main"
902 Just f -> doWithArgs args f
904 runRun :: String -> GHCi ()
905 runRun s = case toCmdArgs s of
906 Left err -> io (hPutStrLn stderr err)
907 Right (cmd, args) -> doWithArgs args cmd
909 doWithArgs :: [String] -> String -> GHCi ()
910 doWithArgs args cmd = enqueueCommands ["System.Environment.withArgs " ++
911 show args ++ " (" ++ cmd ++ ")"]
913 addModule :: [FilePath] -> GHCi ()
915 revertCAFs -- always revert CAFs on load/add.
916 files <- mapM expandPath files
917 targets <- mapM (\m -> io (GHC.guessTarget m Nothing)) files
918 session <- getSession
919 io (mapM_ (GHC.addTarget session) targets)
920 prev_context <- io $ GHC.getContext session
921 ok <- io (GHC.load session LoadAllTargets)
922 afterLoad ok session False prev_context
924 changeDirectory :: String -> GHCi ()
925 changeDirectory "" = do
926 -- :cd on its own changes to the user's home directory
927 either_dir <- io (IO.try getHomeDirectory)
930 Right dir -> changeDirectory dir
931 changeDirectory dir = do
932 session <- getSession
933 graph <- io (GHC.getModuleGraph session)
934 when (not (null graph)) $
935 io $ putStr "Warning: changing directory causes all loaded modules to be unloaded,\nbecause the search path has changed.\n"
936 prev_context <- io $ GHC.getContext session
937 io (GHC.setTargets session [])
938 io (GHC.load session LoadAllTargets)
939 setContextAfterLoad session prev_context False []
940 io (GHC.workingDirectoryChanged session)
941 dir <- expandPath dir
942 io (setCurrentDirectory dir)
944 editFile :: String -> GHCi ()
946 do file <- if null str then chooseEditFile else return str
950 $ ghcError (CmdLineError "editor not set, use :set editor")
951 io $ system (cmd ++ ' ':file)
954 -- The user didn't specify a file so we pick one for them.
955 -- Our strategy is to pick the first module that failed to load,
956 -- or otherwise the first target.
958 -- XXX: Can we figure out what happened if the depndecy analysis fails
959 -- (e.g., because the porgrammeer mistyped the name of a module)?
960 -- XXX: Can we figure out the location of an error to pass to the editor?
961 -- XXX: if we could figure out the list of errors that occured during the
962 -- last load/reaload, then we could start the editor focused on the first
964 chooseEditFile :: GHCi String
966 do session <- getSession
967 let hasFailed x = io $ fmap not $ GHC.isLoaded session $ GHC.ms_mod_name x
969 graph <- io (GHC.getModuleGraph session)
970 failed_graph <- filterM hasFailed graph
971 let order g = flattenSCCs $ GHC.topSortModuleGraph True g Nothing
973 x : _ -> GHC.ml_hs_file (GHC.ms_location x)
976 case pick (order failed_graph) of
977 Just file -> return file
979 do targets <- io (GHC.getTargets session)
980 case msum (map fromTarget targets) of
981 Just file -> return file
982 Nothing -> ghcError (CmdLineError "No files to edit.")
984 where fromTarget (GHC.Target (GHC.TargetFile f _) _) = Just f
985 fromTarget _ = Nothing -- when would we get a module target?
987 defineMacro :: Bool{-overwrite-} -> String -> GHCi ()
988 defineMacro overwrite s = do
989 let (macro_name, definition) = break isSpace s
990 macros <- io (readIORef macros_ref)
991 let defined = map cmdName macros
994 then io $ putStrLn "no macros defined"
995 else io $ putStr ("the following macros are defined:\n" ++
998 if (not overwrite && macro_name `elem` defined)
999 then ghcError (CmdLineError
1000 ("macro '" ++ macro_name ++ "' is already defined"))
1003 let filtered = [ cmd | cmd <- macros, cmdName cmd /= macro_name ]
1005 -- give the expression a type signature, so we can be sure we're getting
1006 -- something of the right type.
1007 let new_expr = '(' : definition ++ ") :: String -> IO String"
1009 -- compile the expression
1011 maybe_hv <- io (GHC.compileExpr cms new_expr)
1013 Nothing -> return ()
1014 Just hv -> io (writeIORef macros_ref --
1015 (filtered ++ [(macro_name, runMacro hv, Nothing, completeNone)]))
1017 runMacro :: GHC.HValue{-String -> IO String-} -> String -> GHCi Bool
1019 str <- io ((unsafeCoerce# fun :: String -> IO String) s)
1020 enqueueCommands (lines str)
1023 undefineMacro :: String -> GHCi ()
1024 undefineMacro str = mapM_ undef (words str)
1025 where undef macro_name = do
1026 cmds <- io (readIORef macros_ref)
1027 if (macro_name `notElem` map cmdName cmds)
1028 then ghcError (CmdLineError
1029 ("macro '" ++ macro_name ++ "' is not defined"))
1031 io (writeIORef macros_ref (filter ((/= macro_name) . cmdName) cmds))
1033 cmdCmd :: String -> GHCi ()
1035 let expr = '(' : str ++ ") :: IO String"
1036 session <- getSession
1037 maybe_hv <- io (GHC.compileExpr session expr)
1039 Nothing -> return ()
1041 cmds <- io $ (unsafeCoerce# hv :: IO String)
1042 enqueueCommands (lines cmds)
1045 loadModule :: [(FilePath, Maybe Phase)] -> GHCi SuccessFlag
1046 loadModule fs = timeIt (loadModule' fs)
1048 loadModule_ :: [FilePath] -> GHCi ()
1049 loadModule_ fs = do loadModule (zip fs (repeat Nothing)); return ()
1051 loadModule' :: [(FilePath, Maybe Phase)] -> GHCi SuccessFlag
1052 loadModule' files = do
1053 session <- getSession
1054 prev_context <- io $ GHC.getContext session
1057 discardActiveBreakPoints
1058 io (GHC.setTargets session [])
1059 io (GHC.load session LoadAllTargets)
1062 let (filenames, phases) = unzip files
1063 exp_filenames <- mapM expandPath filenames
1064 let files' = zip exp_filenames phases
1065 targets <- io (mapM (uncurry GHC.guessTarget) files')
1067 -- NOTE: we used to do the dependency anal first, so that if it
1068 -- fails we didn't throw away the current set of modules. This would
1069 -- require some re-working of the GHC interface, so we'll leave it
1070 -- as a ToDo for now.
1072 io (GHC.setTargets session targets)
1073 doLoad session False prev_context LoadAllTargets
1075 checkModule :: String -> GHCi ()
1077 let modl = GHC.mkModuleName m
1078 session <- getSession
1079 prev_context <- io $ GHC.getContext session
1080 result <- io (GHC.checkModule session modl False)
1082 Nothing -> io $ putStrLn "Nothing"
1083 Just r -> io $ putStrLn (showSDoc (
1084 case GHC.checkedModuleInfo r of
1085 Just cm | Just scope <- GHC.modInfoTopLevelScope cm ->
1087 (local,global) = partition ((== modl) . GHC.moduleName . GHC.nameModule) scope
1089 (text "global names: " <+> ppr global) $$
1090 (text "local names: " <+> ppr local)
1092 afterLoad (successIf (isJust result)) session False prev_context
1094 reloadModule :: String -> GHCi ()
1096 session <- getSession
1097 prev_context <- io $ GHC.getContext session
1098 doLoad session True prev_context $
1099 if null m then LoadAllTargets
1100 else LoadUpTo (GHC.mkModuleName m)
1103 doLoad :: Session -> Bool -> ([Module],[Module]) -> LoadHowMuch -> GHCi SuccessFlag
1104 doLoad session retain_context prev_context howmuch = do
1105 -- turn off breakpoints before we load: we can't turn them off later, because
1106 -- the ModBreaks will have gone away.
1107 discardActiveBreakPoints
1108 ok <- io (GHC.load session howmuch)
1109 afterLoad ok session retain_context prev_context
1112 afterLoad :: SuccessFlag -> Session -> Bool -> ([Module],[Module]) -> GHCi ()
1113 afterLoad ok session retain_context prev_context = do
1114 revertCAFs -- always revert CAFs on load.
1116 loaded_mod_summaries <- getLoadedModules session
1117 let loaded_mods = map GHC.ms_mod loaded_mod_summaries
1118 loaded_mod_names = map GHC.moduleName loaded_mods
1119 modulesLoadedMsg ok loaded_mod_names
1121 setContextAfterLoad session prev_context retain_context loaded_mod_summaries
1124 setContextAfterLoad :: Session -> ([Module],[Module]) -> Bool -> [GHC.ModSummary] -> GHCi ()
1125 setContextAfterLoad session prev keep_ctxt [] = do
1126 prel_mod <- getPrelude
1127 setContextKeepingPackageModules session prev keep_ctxt ([], [prel_mod])
1128 setContextAfterLoad session prev keep_ctxt ms = do
1129 -- load a target if one is available, otherwise load the topmost module.
1130 targets <- io (GHC.getTargets session)
1131 case [ m | Just m <- map (findTarget ms) targets ] of
1133 let graph' = flattenSCCs (GHC.topSortModuleGraph True ms Nothing) in
1134 load_this (last graph')
1139 = case filter (`matches` t) ms of
1143 summary `matches` Target (TargetModule m) _
1144 = GHC.ms_mod_name summary == m
1145 summary `matches` Target (TargetFile f _) _
1146 | Just f' <- GHC.ml_hs_file (GHC.ms_location summary) = f == f'
1150 load_this summary | m <- GHC.ms_mod summary = do
1151 b <- io (GHC.moduleIsInterpreted session m)
1152 if b then setContextKeepingPackageModules session prev keep_ctxt ([m], [])
1154 prel_mod <- getPrelude
1155 setContextKeepingPackageModules session prev keep_ctxt ([],[prel_mod,m])
1157 -- | Keep any package modules (except Prelude) when changing the context.
1158 setContextKeepingPackageModules
1160 -> ([Module],[Module]) -- previous context
1161 -> Bool -- re-execute :module commands
1162 -> ([Module],[Module]) -- new context
1164 setContextKeepingPackageModules session prev_context keep_ctxt (as,bs) = do
1165 let (_,bs0) = prev_context
1166 prel_mod <- getPrelude
1167 let pkg_modules = filter (\p -> not (isHomeModule p) && p /= prel_mod) bs0
1168 let bs1 = if null as then nub (prel_mod : bs) else bs
1169 io $ GHC.setContext session as (nub (bs1 ++ pkg_modules))
1173 mapM_ (playCtxtCmd False) (remembered_ctx st)
1176 setGHCiState st{ remembered_ctx = [] }
1178 isHomeModule :: Module -> Bool
1179 isHomeModule mod = GHC.modulePackageId mod == mainPackageId
1181 modulesLoadedMsg :: SuccessFlag -> [ModuleName] -> GHCi ()
1182 modulesLoadedMsg ok mods = do
1183 dflags <- getDynFlags
1184 when (verbosity dflags > 0) $ do
1186 | null mods = text "none."
1187 | otherwise = hsep (
1188 punctuate comma (map ppr mods)) <> text "."
1191 io (putStrLn (showSDoc (text "Failed, modules loaded: " <> mod_commas)))
1193 io (putStrLn (showSDoc (text "Ok, modules loaded: " <> mod_commas)))
1196 typeOfExpr :: String -> GHCi ()
1198 = do cms <- getSession
1199 maybe_ty <- io (GHC.exprType cms str)
1201 Nothing -> return ()
1202 Just ty -> do dflags <- getDynFlags
1203 let pefas = dopt Opt_PrintExplicitForalls dflags
1204 printForUser $ text str <+> dcolon
1205 <+> pprTypeForUser pefas ty
1207 kindOfType :: String -> GHCi ()
1209 = do cms <- getSession
1210 maybe_ty <- io (GHC.typeKind cms str)
1212 Nothing -> return ()
1213 Just ty -> printForUser $ text str <+> dcolon <+> ppr ty
1215 quit :: String -> GHCi Bool
1216 quit _ = return True
1218 shellEscape :: String -> GHCi Bool
1219 shellEscape str = io (system str >> return False)
1221 -----------------------------------------------------------------------------
1222 -- Browsing a module's contents
1224 browseCmd :: Bool -> String -> GHCi ()
1227 ['*':s] | looksLikeModuleName s -> do
1228 m <- wantInterpretedModule s
1229 browseModule bang m False
1230 [s] | looksLikeModuleName s -> do
1232 browseModule bang m True
1235 (as,bs) <- io $ GHC.getContext s
1236 -- Guess which module the user wants to browse. Pick
1237 -- modules that are interpreted first. The most
1238 -- recently-added module occurs last, it seems.
1240 (as@(_:_), _) -> browseModule bang (last as) True
1241 ([], bs@(_:_)) -> browseModule bang (last bs) True
1242 ([], []) -> ghcError (CmdLineError ":browse: no current module")
1243 _ -> ghcError (CmdLineError "syntax: :browse <module>")
1245 -- without bang, show items in context of their parents and omit children
1246 -- with bang, show class methods and data constructors separately, and
1247 -- indicate import modules, to aid qualifying unqualified names
1248 -- with sorted, sort items alphabetically
1249 browseModule :: Bool -> Module -> Bool -> GHCi ()
1250 browseModule bang modl exports_only = do
1252 -- :browse! reports qualifiers wrt current context
1253 current_unqual <- io (GHC.getPrintUnqual s)
1254 -- Temporarily set the context to the module we're interested in,
1255 -- just so we can get an appropriate PrintUnqualified
1256 (as,bs) <- io (GHC.getContext s)
1257 prel_mod <- getPrelude
1258 io (if exports_only then GHC.setContext s [] [prel_mod,modl]
1259 else GHC.setContext s [modl] [])
1260 target_unqual <- io (GHC.getPrintUnqual s)
1261 io (GHC.setContext s as bs)
1263 let unqual = if bang then current_unqual else target_unqual
1265 mb_mod_info <- io $ GHC.getModuleInfo s modl
1267 Nothing -> ghcError (CmdLineError ("unknown module: " ++
1268 GHC.moduleNameString (GHC.moduleName modl)))
1270 dflags <- getDynFlags
1272 | exports_only = GHC.modInfoExports mod_info
1273 | otherwise = GHC.modInfoTopLevelScope mod_info
1276 -- sort alphabetically name, but putting
1277 -- locally-defined identifiers first.
1278 -- We would like to improve this; see #1799.
1279 sorted_names = loc_sort local ++ occ_sort external
1281 (local,external) = partition ((==modl) . nameModule) names
1282 occ_sort = sortBy (compare `on` nameOccName)
1283 -- try to sort by src location. If the first name in
1284 -- our list has a good source location, then they all should.
1286 | n:_ <- names, isGoodSrcSpan (nameSrcSpan n)
1287 = sortBy (compare `on` nameSrcSpan) names
1291 mb_things <- io $ mapM (GHC.lookupName s) sorted_names
1292 let filtered_things = filterOutChildren (\t -> t) (catMaybes mb_things)
1294 rdr_env <- io $ GHC.getGRE s
1296 let pefas = dopt Opt_PrintExplicitForalls dflags
1297 things | bang = catMaybes mb_things
1298 | otherwise = filtered_things
1299 pretty | bang = pprTyThing
1300 | otherwise = pprTyThingInContext
1302 labels [] = text "-- not currently imported"
1303 labels l = text $ intercalate "\n" $ map qualifier l
1304 qualifier = maybe "-- defined locally"
1305 (("-- imported via "++) . intercalate ", "
1306 . map GHC.moduleNameString)
1307 importInfo = RdrName.getGRE_NameQualifier_maybes rdr_env
1308 modNames = map (importInfo . GHC.getName) things
1310 -- annotate groups of imports with their import modules
1311 -- the default ordering is somewhat arbitrary, so we group
1312 -- by header and sort groups; the names themselves should
1313 -- really come in order of source appearance.. (trac #1799)
1314 annotate mts = concatMap (\(m,ts)->labels m:ts)
1315 $ sortBy cmpQualifiers $ group mts
1316 where cmpQualifiers =
1317 compare `on` (map (fmap (map moduleNameFS)) . fst)
1319 group mts@((m,_):_) = (m,map snd g) : group ng
1320 where (g,ng) = partition ((==m).fst) mts
1322 let prettyThings = map (pretty pefas) things
1323 prettyThings' | bang = annotate $ zip modNames prettyThings
1324 | otherwise = prettyThings
1325 io (putStrLn $ showSDocForUser unqual (vcat prettyThings'))
1326 -- ToDo: modInfoInstances currently throws an exception for
1327 -- package modules. When it works, we can do this:
1328 -- $$ vcat (map GHC.pprInstance (GHC.modInfoInstances mod_info))
1330 -----------------------------------------------------------------------------
1331 -- Setting the module context
1333 setContext :: String -> GHCi ()
1335 | all sensible strs = do
1336 playCtxtCmd True (cmd, as, bs)
1338 setGHCiState st{ remembered_ctx = remembered_ctx st ++ [(cmd,as,bs)] }
1339 | otherwise = ghcError (CmdLineError "syntax: :module [+/-] [*]M1 ... [*]Mn")
1341 (cmd, strs, as, bs) =
1343 '+':stuff -> rest AddModules stuff
1344 '-':stuff -> rest RemModules stuff
1345 stuff -> rest SetContext stuff
1347 rest cmd stuff = (cmd, strs, as, bs)
1348 where strs = words stuff
1349 (as,bs) = partitionWith starred strs
1351 sensible ('*':m) = looksLikeModuleName m
1352 sensible m = looksLikeModuleName m
1354 starred ('*':m) = Left m
1357 playCtxtCmd :: Bool -> (CtxtCmd, [String], [String]) -> GHCi ()
1358 playCtxtCmd fail (cmd, as, bs)
1361 (as',bs') <- do_checks fail
1362 (prev_as,prev_bs) <- io $ GHC.getContext s
1366 prel_mod <- getPrelude
1367 let bs'' = if null as && prel_mod `notElem` bs' then prel_mod:bs'
1371 let as_to_add = as' \\ (prev_as ++ prev_bs)
1372 bs_to_add = bs' \\ (prev_as ++ prev_bs)
1373 return (prev_as ++ as_to_add, prev_bs ++ bs_to_add)
1375 let new_as = prev_as \\ (as' ++ bs')
1376 new_bs = prev_bs \\ (as' ++ bs')
1377 return (new_as, new_bs)
1378 io $ GHC.setContext s new_as new_bs
1381 as' <- mapM wantInterpretedModule as
1382 bs' <- mapM lookupModule bs
1384 do_checks False = do
1385 as' <- mapM (trymaybe . wantInterpretedModule) as
1386 bs' <- mapM (trymaybe . lookupModule) bs
1387 return (catMaybes as', catMaybes bs')
1392 Left _ -> return Nothing
1393 Right a -> return (Just a)
1395 ----------------------------------------------------------------------------
1398 -- set options in the interpreter. Syntax is exactly the same as the
1399 -- ghc command line, except that certain options aren't available (-C,
1402 -- This is pretty fragile: most options won't work as expected. ToDo:
1403 -- figure out which ones & disallow them.
1405 setCmd :: String -> GHCi ()
1407 = do st <- getGHCiState
1408 let opts = options st
1409 io $ putStrLn (showSDoc (
1410 text "options currently set: " <>
1413 else hsep (map (\o -> char '+' <> text (optToStr o)) opts)
1415 dflags <- getDynFlags
1416 io $ putStrLn (showSDoc (
1417 vcat (text "GHCi-specific dynamic flag settings:"
1418 :map (flagSetting dflags) ghciFlags)
1420 io $ putStrLn (showSDoc (
1421 vcat (text "other dynamic, non-language, flag settings:"
1422 :map (flagSetting dflags) nonLanguageDynFlags)
1424 where flagSetting dflags (str, f, _)
1425 | dopt f dflags = text " " <> text "-f" <> text str
1426 | otherwise = text " " <> text "-fno-" <> text str
1427 (ghciFlags,others) = partition (\(_, f, _) -> f `elem` flags)
1429 nonLanguageDynFlags = filterOut (\(_, f, _) -> f `elem` languageOptions)
1431 flags = [Opt_PrintExplicitForalls
1432 ,Opt_PrintBindResult
1433 ,Opt_BreakOnException
1435 ,Opt_PrintEvldWithShow
1438 = case getCmd str of
1439 Right ("args", rest) ->
1441 Left err -> io (hPutStrLn stderr err)
1442 Right args -> setArgs args
1443 Right ("prog", rest) ->
1445 Right [prog] -> setProg prog
1446 _ -> io (hPutStrLn stderr "syntax: :set prog <progname>")
1447 Right ("prompt", rest) -> setPrompt $ dropWhile isSpace rest
1448 Right ("editor", rest) -> setEditor $ dropWhile isSpace rest
1449 Right ("stop", rest) -> setStop $ dropWhile isSpace rest
1450 _ -> case toArgs str of
1451 Left err -> io (hPutStrLn stderr err)
1452 Right wds -> setOptions wds
1454 setArgs, setOptions :: [String] -> GHCi ()
1455 setProg, setEditor, setStop, setPrompt :: String -> GHCi ()
1459 setGHCiState st{ args = args }
1463 setGHCiState st{ progname = prog }
1467 setGHCiState st{ editor = cmd }
1469 setStop str@(c:_) | isDigit c
1470 = do let (nm_str,rest) = break (not.isDigit) str
1473 let old_breaks = breaks st
1474 if all ((/= nm) . fst) old_breaks
1475 then printForUser (text "Breakpoint" <+> ppr nm <+>
1476 text "does not exist")
1478 let new_breaks = map fn old_breaks
1479 fn (i,loc) | i == nm = (i,loc { onBreakCmd = dropWhile isSpace rest })
1480 | otherwise = (i,loc)
1481 setGHCiState st{ breaks = new_breaks }
1484 setGHCiState st{ stop = cmd }
1486 setPrompt value = do
1489 then io $ hPutStrLn stderr $ "syntax: :set prompt <prompt>, currently \"" ++ prompt st ++ "\""
1490 else setGHCiState st{ prompt = remQuotes value }
1492 remQuotes ('\"':xs) | not (null xs) && last xs == '\"' = init xs
1496 do -- first, deal with the GHCi opts (+s, +t, etc.)
1497 let (plus_opts, minus_opts) = partitionWith isPlus wds
1498 mapM_ setOpt plus_opts
1499 -- then, dynamic flags
1500 newDynFlags minus_opts
1502 newDynFlags :: [String] -> GHCi ()
1503 newDynFlags minus_opts = do
1504 dflags <- getDynFlags
1505 let pkg_flags = packageFlags dflags
1506 (dflags', leftovers, warns) <- io $ GHC.parseDynamicFlags dflags minus_opts
1507 io $ handleFlagWarnings dflags' warns
1509 if (not (null leftovers))
1510 then ghcError (CmdLineError ("unrecognised flags: " ++
1514 new_pkgs <- setDynFlags dflags'
1516 -- if the package flags changed, we should reset the context
1517 -- and link the new packages.
1518 dflags <- getDynFlags
1519 when (packageFlags dflags /= pkg_flags) $ do
1520 io $ hPutStrLn stderr "package flags have changed, ressetting and loading new packages..."
1521 session <- getSession
1522 io (GHC.setTargets session [])
1523 io (GHC.load session LoadAllTargets)
1524 io (linkPackages dflags new_pkgs)
1525 -- package flags changed, we can't re-use any of the old context
1526 setContextAfterLoad session ([],[]) False []
1530 unsetOptions :: String -> GHCi ()
1532 = do -- first, deal with the GHCi opts (+s, +t, etc.)
1533 let opts = words str
1534 (minus_opts, rest1) = partition isMinus opts
1535 (plus_opts, rest2) = partitionWith isPlus rest1
1537 if (not (null rest2))
1538 then io (putStrLn ("unknown option: '" ++ head rest2 ++ "'"))
1541 mapM_ unsetOpt plus_opts
1543 let no_flag ('-':'f':rest) = return ("-fno-" ++ rest)
1544 no_flag f = ghcError (ProgramError ("don't know how to reverse " ++ f))
1546 no_flags <- mapM no_flag minus_opts
1547 newDynFlags no_flags
1549 isMinus :: String -> Bool
1550 isMinus ('-':_) = True
1553 isPlus :: String -> Either String String
1554 isPlus ('+':opt) = Left opt
1555 isPlus other = Right other
1557 setOpt, unsetOpt :: String -> GHCi ()
1560 = case strToGHCiOpt str of
1561 Nothing -> io (putStrLn ("unknown option: '" ++ str ++ "'"))
1562 Just o -> setOption o
1565 = case strToGHCiOpt str of
1566 Nothing -> io (putStrLn ("unknown option: '" ++ str ++ "'"))
1567 Just o -> unsetOption o
1569 strToGHCiOpt :: String -> (Maybe GHCiOption)
1570 strToGHCiOpt "s" = Just ShowTiming
1571 strToGHCiOpt "t" = Just ShowType
1572 strToGHCiOpt "r" = Just RevertCAFs
1573 strToGHCiOpt _ = Nothing
1575 optToStr :: GHCiOption -> String
1576 optToStr ShowTiming = "s"
1577 optToStr ShowType = "t"
1578 optToStr RevertCAFs = "r"
1580 -- ---------------------------------------------------------------------------
1583 showCmd :: String -> GHCi ()
1587 ["args"] -> io $ putStrLn (show (args st))
1588 ["prog"] -> io $ putStrLn (show (progname st))
1589 ["prompt"] -> io $ putStrLn (show (prompt st))
1590 ["editor"] -> io $ putStrLn (show (editor st))
1591 ["stop"] -> io $ putStrLn (show (stop st))
1592 ["modules" ] -> showModules
1593 ["bindings"] -> showBindings
1594 ["linker"] -> io showLinkerState
1595 ["breaks"] -> showBkptTable
1596 ["context"] -> showContext
1597 ["packages"] -> showPackages
1598 ["languages"] -> showLanguages
1599 _ -> ghcError (CmdLineError ("syntax: :show [ args | prog | prompt | editor | stop | modules | bindings\n"++
1600 " | breaks | context | packages | languages ]"))
1602 showModules :: GHCi ()
1604 session <- getSession
1605 loaded_mods <- getLoadedModules session
1606 -- we want *loaded* modules only, see #1734
1607 let show_one ms = do m <- io (GHC.showModule session ms); io (putStrLn m)
1608 mapM_ show_one loaded_mods
1610 getLoadedModules :: GHC.Session -> GHCi [GHC.ModSummary]
1611 getLoadedModules session = do
1612 graph <- io (GHC.getModuleGraph session)
1613 filterM (io . GHC.isLoaded session . GHC.ms_mod_name) graph
1615 showBindings :: GHCi ()
1618 bindings <- io (GHC.getBindings s)
1619 docs <- io$ pprTypeAndContents s
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 session <- getSession
1639 resumes <- io $ GHC.getResumeContext session
1640 printForUser $ vcat (map pp_resume (reverse resumes))
1643 ptext (sLit "--> ") <> text (GHC.resumeStmt resume)
1644 $$ nest 2 (ptext (sLit "Stopped at") <+> ppr (GHC.resumeSpan resume))
1646 showPackages :: GHCi ()
1648 pkg_flags <- fmap packageFlags getDynFlags
1649 io $ putStrLn $ showSDoc $ vcat $
1650 text ("active package flags:"++if null pkg_flags then " none" else "")
1651 : map showFlag pkg_flags
1652 pkg_ids <- fmap (preloadPackages . pkgState) getDynFlags
1653 io $ putStrLn $ showSDoc $ vcat $
1654 text "packages currently loaded:"
1655 : map (nest 2 . text . packageIdString)
1656 (sortBy (compare `on` packageIdFS) pkg_ids)
1657 where showFlag (ExposePackage p) = text $ " -package " ++ p
1658 showFlag (HidePackage p) = text $ " -hide-package " ++ p
1659 showFlag (IgnorePackage p) = text $ " -ignore-package " ++ p
1661 showLanguages :: GHCi ()
1663 dflags <- getDynFlags
1664 io $ putStrLn $ showSDoc $ vcat $
1665 text "active language flags:" :
1666 [text (" -X" ++ str) | (str, f, _) <- DynFlags.xFlags, dopt f dflags]
1668 -- -----------------------------------------------------------------------------
1671 completeNone :: String -> IO [String]
1672 completeNone _w = return []
1674 completeMacro, completeIdentifier, completeModule,
1675 completeHomeModule, completeSetOptions, completeFilename,
1676 completeHomeModuleOrFile
1677 :: String -> IO [String]
1680 completeWord :: String -> Int -> Int -> IO (Maybe (String, [String]))
1681 completeWord w start end = do
1682 line <- Readline.getLineBuffer
1683 let line_words = words (dropWhile isSpace line)
1685 ':':_ | all isSpace (take (start-1) line) -> wrapCompleter completeCmd w
1687 | ((':':c) : _) <- line_words -> do
1688 completionVars <- lookupCompletionVars c
1689 case completionVars of
1690 (Nothing,complete) -> wrapCompleter complete w
1691 (Just breakChars,complete)
1692 -> let (n,w') = selectWord
1693 (words' (`elem` breakChars) 0 line)
1694 complete' w = do rets <- complete w
1695 return (map (drop n) rets)
1696 in wrapCompleter complete' w'
1697 | ("import" : _) <- line_words ->
1698 wrapCompleter completeModule w
1700 --printf "complete %s, start = %d, end = %d\n" w start end
1701 wrapCompleter completeIdentifier w
1702 where words' _ _ [] = []
1703 words' isBreak n str = let (w,r) = break isBreak str
1704 (s,r') = span isBreak r
1705 in (n,w):words' isBreak (n+length w+length s) r'
1706 -- In a Haskell expression we want to parse 'a-b' as three words
1707 -- where a compiler flag (e.g. -ddump-simpl) should
1708 -- only be a single word.
1709 selectWord [] = (0,w)
1710 selectWord ((offset,x):xs)
1711 | offset+length x >= start = (start-offset,take (end-offset) x)
1712 | otherwise = selectWord xs
1714 lookupCompletionVars ('!':_) = return (Just filenameWordBreakChars,
1716 lookupCompletionVars c = do
1717 maybe_cmd <- lookupCommand' c
1719 Just (_,_,ws,f) -> return (ws,f)
1720 Nothing -> return (Just filenameWordBreakChars,
1724 completeCmd :: String -> IO [String]
1726 cmds <- readIORef macros_ref
1727 return (filter (w `isPrefixOf`) (map (':':)
1728 (map cmdName (builtin_commands ++ cmds))))
1730 completeMacro w = do
1731 cmds <- readIORef macros_ref
1732 return (filter (w `isPrefixOf`) (map cmdName cmds))
1734 completeIdentifier w = do
1736 rdrs <- GHC.getRdrNamesInScope s
1737 return (filter (w `isPrefixOf`) (map (showSDoc.ppr) rdrs))
1739 completeModule w = do
1741 dflags <- GHC.getSessionDynFlags s
1742 let pkg_mods = allExposedModules dflags
1743 return (filter (w `isPrefixOf`) (map (showSDoc.ppr) pkg_mods))
1745 completeHomeModule w = do
1747 g <- GHC.getModuleGraph s
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":allFlags
1755 completeFilename w = do
1756 ws <- Readline.filenameCompletionFunction w
1758 -- If we only found one result, and it's a directory,
1759 -- add a trailing slash.
1761 isDir <- expandPathIO file >>= doesDirectoryExist
1762 if isDir && last file /= '/'
1763 then return [file ++ "/"]
1768 completeHomeModuleOrFile = unionComplete completeHomeModule completeFilename
1770 unionComplete :: (String -> IO [String]) -> (String -> IO [String]) -> String -> IO [String]
1771 unionComplete f1 f2 w = do
1776 wrapCompleter :: (String -> IO [String]) -> String -> IO (Maybe (String,[String]))
1777 wrapCompleter fun w = do
1780 [] -> Readline.setAttemptedCompletionOver True >> return Nothing
1781 [x] -> -- Add a trailing space, unless it already has an appended slash.
1782 let appended = if last x == '/' then x else x ++ " "
1783 in return (Just (appended,[]))
1784 xs -> case getCommonPrefix xs of
1785 "" -> return (Just ("",xs))
1786 pref -> return (Just (pref,xs))
1788 getCommonPrefix :: [String] -> String
1789 getCommonPrefix [] = ""
1790 getCommonPrefix (s:ss) = foldl common s ss
1791 where common _s "" = ""
1793 common (c:cs) (d:ds)
1794 | c == d = c : common cs ds
1797 allExposedModules :: DynFlags -> [ModuleName]
1798 allExposedModules dflags
1799 = concat (map exposedModules (filter exposed (eltsUFM pkg_db)))
1801 pkg_db = pkgIdMap (pkgState dflags)
1803 completeMacro = completeNone
1804 completeIdentifier = completeNone
1805 completeModule = completeNone
1806 completeHomeModule = completeNone
1807 completeSetOptions = completeNone
1808 completeFilename = completeNone
1809 completeHomeModuleOrFile=completeNone
1812 -- ---------------------------------------------------------------------------
1813 -- User code exception handling
1815 -- This is the exception handler for exceptions generated by the
1816 -- user's code and exceptions coming from children sessions;
1817 -- it normally just prints out the exception. The
1818 -- handler must be recursive, in case showing the exception causes
1819 -- more exceptions to be raised.
1821 -- Bugfix: if the user closed stdout or stderr, the flushing will fail,
1822 -- raising another exception. We therefore don't put the recursive
1823 -- handler arond the flushing operation, so if stderr is closed
1824 -- GHCi will just die gracefully rather than going into an infinite loop.
1825 handler :: SomeException -> GHCi Bool
1827 handler exception = do
1829 io installSignalHandlers
1830 ghciHandle handler (showException exception >> return False)
1832 showException :: SomeException -> GHCi ()
1833 #if __GLASGOW_HASKELL__ < 609
1834 showException (DynException dyn) =
1835 case fromDynamic dyn of
1836 Nothing -> io (putStrLn ("*** Exception: (unknown)"))
1837 Just Interrupted -> io (putStrLn "Interrupted.")
1838 Just (CmdLineError s) -> io (putStrLn s) -- omit the location for CmdLineError
1839 Just ph@PhaseFailed{} -> io (putStrLn (showGhcException ph "")) -- ditto
1840 Just other_ghc_ex -> io (print other_ghc_ex)
1842 showException other_exception
1843 = io (putStrLn ("*** Exception: " ++ show other_exception))
1845 showException (SomeException e) =
1847 Just Interrupted -> putStrLn "Interrupted."
1848 -- omit the location for CmdLineError:
1849 Just (CmdLineError s) -> putStrLn s
1851 Just ph@(PhaseFailed {}) -> putStrLn (showGhcException ph "")
1852 Just other_ghc_ex -> print other_ghc_ex
1853 Nothing -> putStrLn ("*** Exception: " ++ show e)
1856 -----------------------------------------------------------------------------
1857 -- recursive exception handlers
1859 -- Don't forget to unblock async exceptions in the handler, or if we're
1860 -- in an exception loop (eg. let a = error a in a) the ^C exception
1861 -- may never be delivered. Thanks to Marcin for pointing out the bug.
1863 ghciHandle :: (SomeException -> GHCi a) -> GHCi a -> GHCi a
1864 ghciHandle h (GHCi m) = GHCi $ \s ->
1865 Exception.catch (m s)
1866 (\e -> unGHCi (ghciUnblock (h e)) s)
1868 ghciUnblock :: GHCi a -> GHCi a
1869 ghciUnblock (GHCi a) = GHCi $ \s -> Exception.unblock (a s)
1871 ghciTry :: GHCi a -> GHCi (Either SomeException a)
1872 ghciTry (GHCi m) = GHCi $ \s -> Exception.try (m s)
1874 -- ----------------------------------------------------------------------------
1877 expandPath :: String -> GHCi String
1878 expandPath path = io (expandPathIO path)
1880 expandPathIO :: String -> IO String
1882 case dropWhile isSpace path of
1884 tilde <- getHomeDirectory -- will fail if HOME not defined
1885 return (tilde ++ '/':d)
1889 wantInterpretedModule :: String -> GHCi Module
1890 wantInterpretedModule str = do
1891 session <- getSession
1892 modl <- lookupModule str
1893 is_interpreted <- io (GHC.moduleIsInterpreted session modl)
1894 when (not is_interpreted) $
1895 ghcError (CmdLineError ("module '" ++ str ++ "' is not interpreted"))
1898 wantNameFromInterpretedModule :: (Name -> SDoc -> GHCi ()) -> String
1899 -> (Name -> GHCi ())
1901 wantNameFromInterpretedModule noCanDo str and_then = do
1902 session <- getSession
1903 names <- io $ GHC.parseName session str
1907 let modl = GHC.nameModule n
1908 if not (GHC.isExternalName n)
1909 then noCanDo n $ ppr n <>
1910 text " is not defined in an interpreted module"
1912 is_interpreted <- io (GHC.moduleIsInterpreted session modl)
1913 if not is_interpreted
1914 then noCanDo n $ text "module " <> ppr modl <>
1915 text " is not interpreted"
1918 -- -----------------------------------------------------------------------------
1919 -- commands for debugger
1921 sprintCmd, printCmd, forceCmd :: String -> GHCi ()
1922 sprintCmd = pprintCommand False False
1923 printCmd = pprintCommand True False
1924 forceCmd = pprintCommand False True
1926 pprintCommand :: Bool -> Bool -> String -> GHCi ()
1927 pprintCommand bind force str = do
1928 session <- getSession
1929 io $ pprintClosureCommand session bind force str
1931 stepCmd :: String -> GHCi ()
1932 stepCmd [] = doContinue (const True) GHC.SingleStep
1933 stepCmd expression = do runStmt expression GHC.SingleStep; return ()
1935 stepLocalCmd :: String -> GHCi ()
1936 stepLocalCmd [] = do
1937 mb_span <- getCurrentBreakSpan
1939 Nothing -> stepCmd []
1941 Just mod <- getCurrentBreakModule
1942 current_toplevel_decl <- enclosingTickSpan mod loc
1943 doContinue (`isSubspanOf` current_toplevel_decl) GHC.SingleStep
1945 stepLocalCmd expression = stepCmd expression
1947 stepModuleCmd :: String -> GHCi ()
1948 stepModuleCmd [] = do
1949 mb_span <- getCurrentBreakSpan
1951 Nothing -> stepCmd []
1953 Just span <- getCurrentBreakSpan
1954 let f some_span = srcSpanFileName_maybe span == srcSpanFileName_maybe some_span
1955 doContinue f GHC.SingleStep
1957 stepModuleCmd expression = stepCmd expression
1959 -- | Returns the span of the largest tick containing the srcspan given
1960 enclosingTickSpan :: Module -> SrcSpan -> GHCi SrcSpan
1961 enclosingTickSpan mod src = do
1962 ticks <- getTickArray mod
1963 let line = srcSpanStartLine src
1964 ASSERT (inRange (bounds ticks) line) do
1965 let enclosing_spans = [ span | (_,span) <- ticks ! line
1966 , srcSpanEnd span >= srcSpanEnd src]
1967 return . head . sortBy leftmost_largest $ enclosing_spans
1969 traceCmd :: String -> GHCi ()
1970 traceCmd [] = doContinue (const True) GHC.RunAndLogSteps
1971 traceCmd expression = do runStmt expression GHC.RunAndLogSteps; return ()
1973 continueCmd :: String -> GHCi ()
1974 continueCmd = noArgs $ doContinue (const True) GHC.RunToCompletion
1976 -- doContinue :: SingleStep -> GHCi ()
1977 doContinue :: (SrcSpan -> Bool) -> SingleStep -> GHCi ()
1978 doContinue pred step = do
1979 runResult <- resume step
1980 afterRunStmt pred runResult
1983 abandonCmd :: String -> GHCi ()
1984 abandonCmd = noArgs $ do
1986 b <- io $ GHC.abandon s -- the prompt will change to indicate the new context
1987 when (not b) $ io $ putStrLn "There is no computation running."
1990 deleteCmd :: String -> GHCi ()
1991 deleteCmd argLine = do
1992 deleteSwitch $ words argLine
1994 deleteSwitch :: [String] -> GHCi ()
1996 io $ putStrLn "The delete command requires at least one argument."
1997 -- delete all break points
1998 deleteSwitch ("*":_rest) = discardActiveBreakPoints
1999 deleteSwitch idents = do
2000 mapM_ deleteOneBreak idents
2002 deleteOneBreak :: String -> GHCi ()
2004 | all isDigit str = deleteBreak (read str)
2005 | otherwise = return ()
2007 historyCmd :: String -> GHCi ()
2009 | null arg = history 20
2010 | all isDigit arg = history (read arg)
2011 | otherwise = io $ putStrLn "Syntax: :history [num]"
2015 resumes <- io $ GHC.getResumeContext s
2017 [] -> io $ putStrLn "Not stopped at a breakpoint"
2019 let hist = GHC.resumeHistory r
2020 (took,rest) = splitAt num hist
2022 [] -> io $ putStrLn $
2023 "Empty history. Perhaps you forgot to use :trace?"
2025 spans <- mapM (io . GHC.getHistorySpan s) took
2026 let nums = map (printf "-%-3d:") [(1::Int)..]
2027 names = map GHC.historyEnclosingDecl took
2028 printForUser (vcat(zipWith3
2029 (\x y z -> x <+> y <+> z)
2031 (map (bold . ppr) names)
2032 (map (parens . ppr) spans)))
2033 io $ putStrLn $ if null rest then "<end of history>" else "..."
2035 bold :: SDoc -> SDoc
2036 bold c | do_bold = text start_bold <> c <> text end_bold
2039 backCmd :: String -> GHCi ()
2040 backCmd = noArgs $ do
2042 (names, _, span) <- io $ GHC.back s
2043 printForUser $ ptext (sLit "Logged breakpoint at") <+> ppr span
2044 printTypeOfNames s names
2045 -- run the command set with ":set stop <cmd>"
2047 enqueueCommands [stop st]
2049 forwardCmd :: String -> GHCi ()
2050 forwardCmd = noArgs $ do
2052 (names, ix, span) <- io $ GHC.forward s
2053 printForUser $ (if (ix == 0)
2054 then ptext (sLit "Stopped at")
2055 else ptext (sLit "Logged breakpoint at")) <+> ppr span
2056 printTypeOfNames s names
2057 -- run the command set with ":set stop <cmd>"
2059 enqueueCommands [stop st]
2061 -- handle the "break" command
2062 breakCmd :: String -> GHCi ()
2063 breakCmd argLine = do
2064 session <- getSession
2065 breakSwitch session $ words argLine
2067 breakSwitch :: Session -> [String] -> GHCi ()
2068 breakSwitch _session [] = do
2069 io $ putStrLn "The break command requires at least one argument."
2070 breakSwitch session (arg1:rest)
2071 | looksLikeModuleName arg1 && not (null rest) = do
2072 mod <- wantInterpretedModule arg1
2073 breakByModule mod rest
2074 | all isDigit arg1 = do
2075 (toplevel, _) <- io $ GHC.getContext session
2077 (mod : _) -> breakByModuleLine mod (read arg1) rest
2079 io $ putStrLn "Cannot find default module for breakpoint."
2080 io $ putStrLn "Perhaps no modules are loaded for debugging?"
2081 | otherwise = do -- try parsing it as an identifier
2082 wantNameFromInterpretedModule noCanDo arg1 $ \name -> do
2083 let loc = GHC.srcSpanStart (GHC.nameSrcSpan name)
2084 if GHC.isGoodSrcLoc loc
2085 then findBreakAndSet (GHC.nameModule name) $
2086 findBreakByCoord (Just (GHC.srcLocFile loc))
2087 (GHC.srcLocLine loc,
2089 else noCanDo name $ text "can't find its location: " <> ppr loc
2091 noCanDo n why = printForUser $
2092 text "cannot set breakpoint on " <> ppr n <> text ": " <> why
2094 breakByModule :: Module -> [String] -> GHCi ()
2095 breakByModule mod (arg1:rest)
2096 | all isDigit arg1 = do -- looks like a line number
2097 breakByModuleLine mod (read arg1) rest
2101 breakByModuleLine :: Module -> Int -> [String] -> GHCi ()
2102 breakByModuleLine mod line args
2103 | [] <- args = findBreakAndSet mod $ findBreakByLine line
2104 | [col] <- args, all isDigit col =
2105 findBreakAndSet mod $ findBreakByCoord Nothing (line, read col)
2106 | otherwise = breakSyntax
2109 breakSyntax = ghcError (CmdLineError "Syntax: :break [<mod>] <line> [<column>]")
2111 findBreakAndSet :: Module -> (TickArray -> Maybe (Int, SrcSpan)) -> GHCi ()
2112 findBreakAndSet mod lookupTickTree = do
2113 tickArray <- getTickArray mod
2114 (breakArray, _) <- getModBreak mod
2115 case lookupTickTree tickArray of
2116 Nothing -> io $ putStrLn $ "No breakpoints found at that location."
2117 Just (tick, span) -> do
2118 success <- io $ setBreakFlag True breakArray tick
2122 recordBreak $ BreakLocation
2129 text "Breakpoint " <> ppr nm <>
2131 then text " was already set at " <> ppr span
2132 else text " activated at " <> ppr span
2134 printForUser $ text "Breakpoint could not be activated at"
2137 -- When a line number is specified, the current policy for choosing
2138 -- the best breakpoint is this:
2139 -- - the leftmost complete subexpression on the specified line, or
2140 -- - the leftmost subexpression starting on the specified line, or
2141 -- - the rightmost subexpression enclosing the specified line
2143 findBreakByLine :: Int -> TickArray -> Maybe (BreakIndex,SrcSpan)
2144 findBreakByLine line arr
2145 | not (inRange (bounds arr) line) = Nothing
2147 listToMaybe (sortBy (leftmost_largest `on` snd) complete) `mplus`
2148 listToMaybe (sortBy (leftmost_smallest `on` snd) incomplete) `mplus`
2149 listToMaybe (sortBy (rightmost `on` snd) ticks)
2153 starts_here = [ tick | tick@(_,span) <- ticks,
2154 GHC.srcSpanStartLine span == line ]
2156 (complete,incomplete) = partition ends_here starts_here
2157 where ends_here (_,span) = GHC.srcSpanEndLine span == line
2159 findBreakByCoord :: Maybe FastString -> (Int,Int) -> TickArray
2160 -> Maybe (BreakIndex,SrcSpan)
2161 findBreakByCoord mb_file (line, col) arr
2162 | not (inRange (bounds arr) line) = Nothing
2164 listToMaybe (sortBy (rightmost `on` snd) contains ++
2165 sortBy (leftmost_smallest `on` snd) after_here)
2169 -- the ticks that span this coordinate
2170 contains = [ tick | tick@(_,span) <- ticks, span `spans` (line,col),
2171 is_correct_file span ]
2173 is_correct_file span
2174 | Just f <- mb_file = GHC.srcSpanFile span == f
2177 after_here = [ tick | tick@(_,span) <- ticks,
2178 GHC.srcSpanStartLine span == line,
2179 GHC.srcSpanStartCol span >= col ]
2181 -- For now, use ANSI bold on terminals that we know support it.
2182 -- Otherwise, we add a line of carets under the active expression instead.
2183 -- In particular, on Windows and when running the testsuite (which sets
2184 -- TERM to vt100 for other reasons) we get carets.
2185 -- We really ought to use a proper termcap/terminfo library.
2187 do_bold = (`isPrefixOf` unsafePerformIO mTerm) `any` ["xterm", "linux"]
2188 where mTerm = System.Environment.getEnv "TERM"
2189 `catchIO` \_ -> return "TERM not set"
2191 start_bold :: String
2192 start_bold = "\ESC[1m"
2194 end_bold = "\ESC[0m"
2196 listCmd :: String -> GHCi ()
2198 mb_span <- getCurrentBreakSpan
2201 printForUser $ text "Not stopped at a breakpoint; nothing to list"
2203 | GHC.isGoodSrcSpan span -> io $ listAround span True
2206 resumes <- io $ GHC.getResumeContext s
2208 [] -> panic "No resumes"
2210 do let traceIt = case GHC.resumeHistory r of
2211 [] -> text "rerunning with :trace,"
2213 doWhat = traceIt <+> text ":back then :list"
2214 printForUser (text "Unable to list source for" <+>
2216 $$ text "Try" <+> doWhat)
2217 listCmd str = list2 (words str)
2219 list2 :: [String] -> GHCi ()
2220 list2 [arg] | all isDigit arg = do
2221 session <- getSession
2222 (toplevel, _) <- io $ GHC.getContext session
2224 [] -> io $ putStrLn "No module to list"
2225 (mod : _) -> listModuleLine mod (read arg)
2226 list2 [arg1,arg2] | looksLikeModuleName arg1, all isDigit arg2 = do
2227 mod <- wantInterpretedModule arg1
2228 listModuleLine mod (read arg2)
2230 wantNameFromInterpretedModule noCanDo arg $ \name -> do
2231 let loc = GHC.srcSpanStart (GHC.nameSrcSpan name)
2232 if GHC.isGoodSrcLoc loc
2234 tickArray <- getTickArray (GHC.nameModule name)
2235 let mb_span = findBreakByCoord (Just (GHC.srcLocFile loc))
2236 (GHC.srcLocLine loc, GHC.srcLocCol loc)
2239 Nothing -> io $ listAround (GHC.srcLocSpan loc) False
2240 Just (_,span) -> io $ listAround span False
2242 noCanDo name $ text "can't find its location: " <>
2245 noCanDo n why = printForUser $
2246 text "cannot list source code for " <> ppr n <> text ": " <> why
2248 io $ putStrLn "syntax: :list [<line> | <module> <line> | <identifier>]"
2250 listModuleLine :: Module -> Int -> GHCi ()
2251 listModuleLine modl line = do
2252 session <- getSession
2253 graph <- io (GHC.getModuleGraph session)
2254 let this = filter ((== modl) . GHC.ms_mod) graph
2256 [] -> panic "listModuleLine"
2258 let filename = fromJust (ml_hs_file (GHC.ms_location summ))
2259 loc = GHC.mkSrcLoc (mkFastString (filename)) line 0
2260 io $ listAround (GHC.srcLocSpan loc) False
2262 -- | list a section of a source file around a particular SrcSpan.
2263 -- If the highlight flag is True, also highlight the span using
2264 -- start_bold\/end_bold.
2265 listAround :: SrcSpan -> Bool -> IO ()
2266 listAround span do_highlight = do
2267 contents <- BS.readFile (unpackFS file)
2269 lines = BS.split '\n' contents
2270 these_lines = take (line2 - line1 + 1 + pad_before + pad_after) $
2271 drop (line1 - 1 - pad_before) $ lines
2272 fst_line = max 1 (line1 - pad_before)
2273 line_nos = [ fst_line .. ]
2275 highlighted | do_highlight = zipWith highlight line_nos these_lines
2276 | otherwise = [\p -> BS.concat[p,l] | l <- these_lines]
2278 bs_line_nos = [ BS.pack (show l ++ " ") | l <- line_nos ]
2279 prefixed = zipWith ($) highlighted bs_line_nos
2281 BS.putStrLn (BS.intercalate (BS.pack "\n") prefixed)
2283 file = GHC.srcSpanFile span
2284 line1 = GHC.srcSpanStartLine span
2285 col1 = GHC.srcSpanStartCol span
2286 line2 = GHC.srcSpanEndLine span
2287 col2 = GHC.srcSpanEndCol span
2289 pad_before | line1 == 1 = 0
2293 highlight | do_bold = highlight_bold
2294 | otherwise = highlight_carets
2296 highlight_bold no line prefix
2297 | no == line1 && no == line2
2298 = let (a,r) = BS.splitAt col1 line
2299 (b,c) = BS.splitAt (col2-col1) r
2301 BS.concat [prefix, a,BS.pack start_bold,b,BS.pack end_bold,c]
2303 = let (a,b) = BS.splitAt col1 line in
2304 BS.concat [prefix, a, BS.pack start_bold, b]
2306 = let (a,b) = BS.splitAt col2 line in
2307 BS.concat [prefix, a, BS.pack end_bold, b]
2308 | otherwise = BS.concat [prefix, line]
2310 highlight_carets no line prefix
2311 | no == line1 && no == line2
2312 = BS.concat [prefix, line, nl, indent, BS.replicate col1 ' ',
2313 BS.replicate (col2-col1) '^']
2315 = BS.concat [indent, BS.replicate (col1 - 2) ' ', BS.pack "vv", nl,
2318 = BS.concat [prefix, line, nl, indent, BS.replicate col2 ' ',
2320 | otherwise = BS.concat [prefix, line]
2322 indent = BS.pack (" " ++ replicate (length (show no)) ' ')
2323 nl = BS.singleton '\n'
2325 -- --------------------------------------------------------------------------
2328 getTickArray :: Module -> GHCi TickArray
2329 getTickArray modl = do
2331 let arrmap = tickarrays st
2332 case lookupModuleEnv arrmap modl of
2333 Just arr -> return arr
2335 (_breakArray, ticks) <- getModBreak modl
2336 let arr = mkTickArray (assocs ticks)
2337 setGHCiState st{tickarrays = extendModuleEnv arrmap modl arr}
2340 discardTickArrays :: GHCi ()
2341 discardTickArrays = do
2343 setGHCiState st{tickarrays = emptyModuleEnv}
2345 mkTickArray :: [(BreakIndex,SrcSpan)] -> TickArray
2347 = accumArray (flip (:)) [] (1, max_line)
2348 [ (line, (nm,span)) | (nm,span) <- ticks,
2349 line <- srcSpanLines span ]
2351 max_line = foldr max 0 (map GHC.srcSpanEndLine (map snd ticks))
2352 srcSpanLines span = [ GHC.srcSpanStartLine span ..
2353 GHC.srcSpanEndLine span ]
2355 lookupModule :: String -> GHCi Module
2356 lookupModule modName
2357 = do session <- getSession
2358 io (GHC.findModule session (GHC.mkModuleName modName) Nothing)
2360 -- don't reset the counter back to zero?
2361 discardActiveBreakPoints :: GHCi ()
2362 discardActiveBreakPoints = do
2364 mapM (turnOffBreak.snd) (breaks st)
2365 setGHCiState $ st { breaks = [] }
2367 deleteBreak :: Int -> GHCi ()
2368 deleteBreak identity = do
2370 let oldLocations = breaks st
2371 (this,rest) = partition (\loc -> fst loc == identity) oldLocations
2373 then printForUser (text "Breakpoint" <+> ppr identity <+>
2374 text "does not exist")
2376 mapM (turnOffBreak.snd) this
2377 setGHCiState $ st { breaks = rest }
2379 turnOffBreak :: BreakLocation -> GHCi Bool
2380 turnOffBreak loc = do
2381 (arr, _) <- getModBreak (breakModule loc)
2382 io $ setBreakFlag False arr (breakTick loc)
2384 getModBreak :: Module -> GHCi (GHC.BreakArray, Array Int SrcSpan)
2385 getModBreak mod = do
2386 session <- getSession
2387 Just mod_info <- io $ GHC.getModuleInfo session mod
2388 let modBreaks = GHC.modInfoModBreaks mod_info
2389 let array = GHC.modBreaks_flags modBreaks
2390 let ticks = GHC.modBreaks_locs modBreaks
2391 return (array, ticks)
2393 setBreakFlag :: Bool -> GHC.BreakArray -> Int -> IO Bool
2394 setBreakFlag toggle array index
2395 | toggle = GHC.setBreakOn array index
2396 | otherwise = GHC.setBreakOff array index