X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Fghci%2FInteractiveUI.hs;h=cce48271df44cabb9a5db9dc9606863b5ea04e60;hb=8c99af6a535d6d09b60a5d172980f8364b1c380c;hp=a420ff6472cfe331ac2607e171d54672279f9f20;hpb=13896d87b75817b068f80d873f828b64403e8023;p=ghc-hetmet.git

diff --git a/ghc/compiler/ghci/InteractiveUI.hs b/ghc/compiler/ghci/InteractiveUI.hs
index a420ff6..cce4827 100644
--- a/ghc/compiler/ghci/InteractiveUI.hs
+++ b/ghc/compiler/ghci/InteractiveUI.hs
@@ -1,5 +1,5 @@
 -----------------------------------------------------------------------------
--- $Id: InteractiveUI.hs,v 1.36 2001/02/09 10:08:09 simonmar Exp $
+-- $Id: InteractiveUI.hs,v 1.60 2001/03/28 16:51:03 simonmar Exp $
 --
 -- GHC Interactive User Interface
 --
@@ -7,7 +7,8 @@
 --
 -----------------------------------------------------------------------------
 
-module InteractiveUI (interactiveUI) where
+{-# OPTIONS -#include "Linker.h" #-}
+module InteractiveUI ( interactiveUI, ghciWelcomeMsg ) where
 
 #include "HsVersions.h"
 
@@ -17,14 +18,13 @@ import ByteCodeLink
 import DriverFlags
 import DriverState
 import DriverUtil
-import Type
 import Linker
-import Finder
-import Module
-import Outputable
 import Util
-import PprType		{- instance Outputable Type; do not delete -}
+import Name		( Name )
+import Outputable
+import CmdLineOpts	( DynFlag(..), dopt_unset )
 import Panic		( GhcException(..) )
+import Config
 
 import Exception
 import Dynamic
@@ -40,23 +40,28 @@ import CPUTime
 import Directory
 import IO
 import Char
-import Monad ( when )
+import Monad 		( when )
 
+import PrelGHC 		( unsafeCoerce# )
+import Foreign		( nullPtr )
+import CString		( peekCString )
 
 -----------------------------------------------------------------------------
 
 ghciWelcomeMsg = "\ 
-\ _____  __   __  ____         _________________________________________________\n\ 
-\(|	 ||   || (|  |)        GHC Interactive, version 5.00   	                \n\ 
-\||  __  ||___|| ||     ()     For Haskell 98.                    		\n\ 
-\||   |) ||---|| ||     ||     http://www.haskell.org/ghc         		\n\ 
-\||   || ||   || ||     (|     Bug reports to: glasgow-haskell-bugs@haskell.org \n\ 
-\(|___|| ||   || (|__|) \\\\______________________________________________________\n"
-
-commands :: [(String, String -> GHCi Bool)]
-commands = [
+\   ___         ___ _\n\ 
+\  / _ \\ /\\  /\\/ __(_)\n\ 
+\ / /_\\// /_/ / /  | |      GHC Interactive, version " ++ cProjectVersion ++ ", For Haskell 98.\n\ 
+\/ /_\\\\/ __  / /___| |      http://www.haskell.org/ghc/\n\ 
+\\\____/\\/ /_/\\____/|_|      Type :? for help.\n"
+
+GLOBAL_VAR(commands, builtin_commands, [(String, String -> GHCi Bool)])
+
+builtin_commands :: [(String, String -> GHCi Bool)]
+builtin_commands = [
   ("add",	keepGoing addModule),
   ("cd",    	keepGoing changeDirectory),
+  ("def",	keepGoing defineMacro),
   ("help",	keepGoing help),
   ("?",		keepGoing help),
   ("load",	keepGoing loadModule),
@@ -65,6 +70,7 @@ commands = [
   ("set",	keepGoing setOptions),
   ("type",	keepGoing typeOfExpr),
   ("unset",	keepGoing unsetOptions),
+  ("undef",     keepGoing undefineMacro),
   ("quit",	quit)
   ]
 
@@ -76,37 +82,39 @@ shortHelpText = "use :? for help.\n"
 helpText = "\ 
 \ Commands available from the prompt:\n\ 
 \\  
-\   <expr>		evaluate <expr>\n\ 
-\   :add <filename>     add a module to the current set\n\ 
+\   <stmt>		evaluate/run <stmt>\n\ 
 \   :cd <dir>		change directory to <dir>\n\ 
+\   :def <cmd> <expr>   define a command :<cmd>\n\ 
 \   :help, :?		display this list of commands\n\ 
 \   :load <filename>    load a module (and it dependents)\n\ 
 \   :module <mod>	set the context for expression evaluation to <mod>\n\ 
 \   :reload		reload the current module set\n\ 
 \   :set <option> ...	set options\n\ 
-\   :unset <option> ...	unset options\n\ 
+\   :undef <name> 	undefine user-defined command :<name>\n\ 
 \   :type <expr>	show the type of <expr>\n\ 
+\   :unset <option> ...	unset options\n\ 
 \   :quit		exit GHCi\n\ 
 \   :!<command>		run the shell command <command>\n\ 
 \\ 
 \ Options for `:set' and `:unset':\n\ 
 \\ 
+\    +r			revert top-level expressions after each evaluation\n\ 
 \    +s                 print timing/memory stats after each evaluation\n\ 
 \    +t			print type after evaluation\n\ 
-\    +r			revert top-level expressions after each evaluation\n\ 
 \    -<flags>		most GHC command line flags can also be set here\n\ 
 \                         (eg. -v2, -fglasgow-exts, etc.)\n\ 
 \"
+ --ToDo   :add <filename>     add a module to the current set\n\ 
 
-interactiveUI :: CmState -> Maybe FilePath -> IO ()
-interactiveUI cmstate mod = do
-   hPutStrLn stdout ghciWelcomeMsg
+interactiveUI :: CmState -> Maybe FilePath -> [LibrarySpec] -> IO ()
+interactiveUI cmstate mod cmdline_libs = do
    hFlush stdout
    hSetBuffering stdout NoBuffering
 
    -- link in the available packages
    pkgs <- getPackageInfo
-   linkPackages (reverse pkgs)
+   initLinker
+   linkPackages cmdline_libs (reverse pkgs)
 
    (cmstate, ok, mods) <-
    	case mod of
@@ -117,33 +125,23 @@ interactiveUI cmstate mod = do
    Readline.initialize
 #endif
 
-   prel <- moduleNameToModule defaultCurrentModuleName
-   writeIORef defaultCurrentModule prel
-
    dflags <- getDynFlags
 
-   (cmstate, maybe_stuff) <- cmGetExpr cmstate dflags False prel 
-		  		"PrelHandle.hFlush PrelHandle.stdout"
-   case maybe_stuff of
-	Nothing -> return ()
-	Just (hv,_,_) -> writeIORef flush_stdout hv
-   
-   (cmstate, maybe_stuff) <- cmGetExpr cmstate dflags False prel 
-		  		"PrelHandle.hFlush PrelHandle.stdout"
-   case maybe_stuff of
-	Nothing -> return ()
-	Just (hv,_,_) -> writeIORef flush_stderr hv
-   
-   let this_mod = case mods of 
-	  	      []   -> prel
-  	  	      m:ms -> m
-
-   (unGHCi runGHCi) GHCiState{ modules = mods,
-			      current_module = this_mod,
-	  	              target = mod,
-			      cmstate = cmstate,
-			      options = [ShowTiming],
-                              last_expr = Nothing}
+   (cmstate, maybe_hval) 
+	<- cmCompileExpr cmstate dflags "IO.hFlush PrelHandle.stderr"
+   case maybe_hval of
+	Just hval -> writeIORef flush_stderr (unsafeCoerce# hval :: IO ())
+	_ -> panic "interactiveUI:stderr"
+
+   (cmstate, maybe_hval) 
+	<- cmCompileExpr cmstate dflags "IO.hFlush PrelHandle.stdout"
+   case maybe_hval of
+	Just hval -> writeIORef flush_stdout (unsafeCoerce# hval :: IO ())
+	_ -> panic "interactiveUI:stdout"
+
+   (unGHCi runGHCi) GHCiState{ target = mod,
+			       cmstate = cmstate,
+			       options = [ShowTiming] }
    return ()
 
 
@@ -160,10 +158,12 @@ runGHCi = do
   case home of
    Left e  -> return ()
    Right dir -> do
-  	dot_ghci <- io (IO.try (openFile (dir ++ "/.ghci") ReadMode))
-	case dot_ghci of
-	   Left e -> return ()
-	   Right hdl -> fileLoop hdl False
+	cwd <- io (getCurrentDirectory)
+	when (dir /= cwd) $ do
+  	  dot_ghci <- io (IO.try (openFile (dir ++ "/.ghci") ReadMode))
+  	  case dot_ghci of
+  	     Left e -> return ()
+  	     Right hdl -> fileLoop hdl False
 
   -- read commands from stdin
 #ifndef NO_READLINE
@@ -179,7 +179,8 @@ runGHCi = do
 fileLoop :: Handle -> Bool -> GHCi ()
 fileLoop hdl prompt = do
    st <- getGHCiState
-   when prompt (io (hPutStr hdl (moduleUserString (current_module st) ++ "> ")))
+   mod <- io (cmGetContext (cmstate st))
+   when prompt (io (hPutStr hdl (mod ++ "> ")))
    l <- io (IO.try (hGetLine hdl))
    case l of
 	Left e | isEOFError e -> return ()
@@ -190,11 +191,21 @@ fileLoop hdl prompt = do
 	    l  -> do quit <- runCommand l
           	     if quit then return () else fileLoop hdl prompt
 
+stringLoop :: [String] -> GHCi ()
+stringLoop [] = return ()
+stringLoop (s:ss) = do
+   st <- getGHCiState
+   case remove_spaces s of
+	"" -> stringLoop ss
+	l  -> do quit <- runCommand l
+                 if quit then return () else stringLoop ss
+
 #ifndef NO_READLINE
 readlineLoop :: GHCi ()
 readlineLoop = do
    st <- getGHCiState
-   l <- io (readline (moduleUserString (current_module st) ++ "> "))
+   mod <- io (cmGetContext (cmstate st))
+   l <- io (readline (mod ++ "> "))
    case l of
 	Nothing -> return ()
 	Just l  ->
@@ -221,6 +232,8 @@ runCommand c =
 			io ( putStrLn ("Phase " ++ phase ++ " failed (code "
 				        ++ show code ++ ")"))
 		    Interrupted -> io (putStrLn "Interrupted.")
+			-- omit the location for CmdLineError
+		    CmdLineError s -> io (putStrLn s)
 		    other -> io (putStrLn (show (ghc_ex :: GhcException)))
 
 	   other -> io (putStrLn ("*** Exception: " ++ show exception))
@@ -231,54 +244,57 @@ runCommand c =
    doCommand c
 
 doCommand (':' : command) = specialCommand command
-doCommand ('-':'-':_) = return False	-- comments, useful in scripts
-doCommand expr
-   = do expr_expanded <- expandExpr expr
-        -- io (putStrLn ( "Before: " ++ expr ++ "\nAfter:  " ++ expr_expanded))
-        expr_ok <- timeIt (do stuff <- evalExpr expr_expanded
-			      finishEvalExpr stuff)
-        when expr_ok (rememberExpr expr_expanded)
+doCommand stmt
+   = do timeIt (do stuff <- runStmt stmt; finishEvalExpr stuff)
         return False
 
+-- Returns True if the expr was successfully parsed, renamed and
+-- typechecked.
+runStmt :: String -> GHCi (Maybe [Name])
+runStmt stmt
+ | null (filter (not.isSpace) stmt)
+ = return Nothing
+ | otherwise
+ = do st <- getGHCiState
+      dflags <- io (getDynFlags)
+      let dflags' = dopt_unset dflags Opt_WarnUnusedBinds
+      (new_cmstate, names) <- io (cmRunStmt (cmstate st) dflags' stmt)
+      setGHCiState st{cmstate = new_cmstate}
+      return (Just names)
+
 -- possibly print the type and revert CAFs after evaluating an expression
 finishEvalExpr Nothing = return False
-finishEvalExpr (Just (unqual,ty))
+finishEvalExpr (Just names)
  = do b <- isOptionSet ShowType
-      io (when b (printForUser stdout unqual (text "::" <+> ppr ty)))
+      st <- getGHCiState
+      when b (mapM_ (showTypeOfName (cmstate st)) names)
+
       b <- isOptionSet RevertCAFs
       io (when b revertCAFs)
+      flushEverything
       return True
 
--- Returned Bool indicates whether or not the expr was successfully
--- parsed, renamed and typechecked.
-evalExpr :: String -> GHCi (Maybe (PrintUnqualified,Type))
-evalExpr expr
- | null (filter (not.isSpace) expr)
- = return Nothing
- | otherwise
- = do st <- getGHCiState
-      dflags <- io (getDynFlags)
-      (new_cmstate, maybe_stuff) <- 
-      	 io (cmGetExpr (cmstate st) dflags True (current_module st) expr)
-      setGHCiState st{cmstate = new_cmstate}
-      case maybe_stuff of
-      	 Nothing -> return Nothing
-      	 Just (hv, unqual, ty) -> do io (cmRunExpr hv)
-		 		     flushEverything
-		 		     return (Just (unqual,ty))
+showTypeOfName :: CmState -> Name -> GHCi ()
+showTypeOfName cmstate n
+   = do maybe_str <- io (cmTypeOfName cmstate n)
+	case maybe_str of
+	  Nothing  -> return ()
+	  Just str -> io (putStrLn (showSDoc (ppr n) ++ " :: " ++ str))
 
 flushEverything :: GHCi ()
 flushEverything
    = io $ do flush_so <- readIORef flush_stdout
-     	     cmRunExpr flush_so
+     	     flush_so
      	     flush_se <- readIORef flush_stdout
-     	     cmRunExpr flush_se
+     	     flush_se
+             return ()
 
 specialCommand :: String -> GHCi Bool
 specialCommand ('!':str) = shellEscape (dropWhile isSpace str)
 specialCommand str = do
   let (cmd,rest) = break isSpace str
-  case [ (s,f) | (s,f) <- commands, prefixMatch cmd s ] of
+  cmds <- io (readIORef commands)
+  case [ (s,f) | (s,f) <- cmds, prefixMatch cmd s ] of
      []      -> io (hPutStr stdout ("unknown command `:" ++ cmd ++ "'\n" 
 		                    ++ shortHelpText) >> return False)
      [(_,f)] -> f (dropWhile isSpace rest)
@@ -287,7 +303,7 @@ specialCommand str = do
 	         	     	       foldr1 (\a b -> a ++ ',':b) (map fst cs)
 					 ++ ")") >> return False)
 
-noArgs c = io (hPutStrLn stdout ("command `:" ++ c ++ "' takes no arguments"))
+noArgs c = throwDyn (CmdLineError ("command `" ++ c ++ "' takes no arguments"))
 
 -----------------------------------------------------------------------------
 -- Commands
@@ -296,32 +312,68 @@ help :: String -> GHCi ()
 help _ = io (putStr helpText)
 
 addModule :: String -> GHCi ()
-addModule _ = throwDyn (OtherError ":add not implemented")
+addModule _ = throwDyn (InstallationError ":add not implemented")
 
 setContext :: String -> GHCi ()
 setContext ""
-  = throwDyn (OtherError "syntax: `:m <module>'")
+  = throwDyn (CmdLineError "syntax: `:m <module>'")
 setContext m | not (isUpper (head m)) || not (all isAlphaNum (tail m))
-  = throwDyn (OtherError ("strange looking module name: `" ++ m ++ "'"))
-setContext mn
-  = do m <- io (moduleNameToModule (mkModuleName mn))
-       st <- getGHCiState
-       if (isHomeModule m && m `notElem` modules st)
-	  then throwDyn (OtherError (showSDoc (quotes (ppr (moduleName m))
-				<+> text "is not currently loaded, use :load")))
-	  else setGHCiState st{current_module = m}
-
-moduleNameToModule :: ModuleName -> IO Module
-moduleNameToModule mn
- = do maybe_stuff <- findModule mn
-      case maybe_stuff of
-	 Nothing -> throwDyn (OtherError ("can't find module `"
-					    ++ moduleNameUserString mn ++ "'"))
-   	 Just (m,_) -> return m
+  = throwDyn (CmdLineError ("strange looking module name: `" ++ m ++ "'"))
+setContext str
+  = do st <- getGHCiState
+       new_cmstate <- io (cmSetContext (cmstate st) str)
+       setGHCiState st{cmstate=new_cmstate}
 
 changeDirectory :: String -> GHCi ()
+changeDirectory ('~':d) = do
+   tilde <- io (getEnv "HOME")	-- will fail if HOME not defined
+   io (setCurrentDirectory (tilde ++ '/':d))
 changeDirectory d = io (setCurrentDirectory d)
 
+defineMacro :: String -> GHCi ()
+defineMacro s = do
+  let (macro_name, definition) = break isSpace s
+  cmds <- io (readIORef commands)
+  if (null macro_name) 
+	then throwDyn (CmdLineError "invalid macro name") 
+	else do
+  if (macro_name `elem` map fst cmds) 
+	then throwDyn (CmdLineError 
+		("command `" ++ macro_name ++ "' is already defined"))
+	else do
+
+  -- give the expression a type signature, so we can be sure we're getting
+  -- something of the right type.
+  let new_expr = '(' : definition ++ ") :: String -> IO String"
+
+  -- compile the expression
+  st <- getGHCiState
+  dflags <- io (getDynFlags)
+  (new_cmstate, maybe_hv) <- io (cmCompileExpr (cmstate st) dflags new_expr)
+  setGHCiState st{cmstate = new_cmstate}
+  case maybe_hv of
+     Nothing -> return ()
+     Just hv -> io (writeIORef commands --
+		    ((macro_name, keepGoing (runMacro hv)) : cmds))
+
+runMacro :: HValue{-String -> IO String-} -> String -> GHCi ()
+runMacro fun s = do
+  str <- io ((unsafeCoerce# fun :: String -> IO String) s)
+  stringLoop (lines str)
+
+undefineMacro :: String -> GHCi ()
+undefineMacro macro_name = do
+  cmds <- io (readIORef commands)
+  if (macro_name `elem` map fst builtin_commands) 
+	then throwDyn (CmdLineError
+		("command `" ++ macro_name ++ "' cannot be undefined"))
+	else do
+  if (macro_name `notElem` map fst cmds) 
+	then throwDyn (CmdLineError 
+		("command `" ++ macro_name ++ "' not defined"))
+	else do
+  io (writeIORef commands (filter ((/= macro_name) . fst) cmds))
+
 loadModule :: String -> GHCi ()
 loadModule path = timeIt (loadModule' path)
 
@@ -330,28 +382,11 @@ loadModule' path = do
   cmstate1 <- io (cmUnload (cmstate state))
   io (revertCAFs)			-- always revert CAFs on load.
   (cmstate2, ok, mods) <- io (cmLoadModule cmstate1 path)
-
-  def_mod <- io (readIORef defaultCurrentModule)
-
-  let new_state = state{
-  			cmstate = cmstate2,
-			modules = mods,
-			current_module = case mods of 
-					   [] -> def_mod
-					   xs -> head xs,
-			target = Just path
-		   }
+  let new_state = state{ cmstate = cmstate2,
+			 target = Just path
+		       }
   setGHCiState new_state
-
-  let mod_commas 
-	| null mods = text "none."
-	| otherwise = hsep (
-	    punctuate comma (map (text.moduleUserString) mods)) <> text "."
-  case ok of
-    False -> 
-       io (putStrLn (showSDoc (text "Failed, modules loaded: " <> mod_commas)))
-    True  -> 
-       io (putStrLn (showSDoc (text "Ok, modules loaded: " <> mod_commas)))
+  modulesLoadedMsg ok mods
 
 reloadModule :: String -> GHCi ()
 reloadModule "" = do
@@ -361,27 +396,33 @@ reloadModule "" = do
    Just path
       -> do io (revertCAFs)		-- always revert CAFs on reload.
 	    (new_cmstate, ok, mods) <- io (cmLoadModule (cmstate state) path)
-	    def_mod <- io (readIORef defaultCurrentModule)
-            setGHCiState 
-               state{cmstate=new_cmstate,
-                     modules = mods,
-                     current_module = case mods of 
-                                         [] -> def_mod
-                                         xs -> head xs
-                    }
+            setGHCiState state{ cmstate=new_cmstate }
+	    modulesLoadedMsg ok mods
 
 reloadModule _ = noArgs ":reload"
 
+
+modulesLoadedMsg ok mods = do
+  let mod_commas 
+	| null mods = text "none."
+	| otherwise = hsep (
+	    punctuate comma (map text mods)) <> text "."
+  case ok of
+    False -> 
+       io (putStrLn (showSDoc (text "Failed, modules loaded: " <> mod_commas)))
+    True  -> 
+       io (putStrLn (showSDoc (text "Ok, modules loaded: " <> mod_commas)))
+
+
 typeOfExpr :: String -> GHCi ()
 typeOfExpr str 
   = do st <- getGHCiState
        dflags <- io (getDynFlags)
-       (new_cmstate, maybe_ty) <- io (cmGetExpr (cmstate st) dflags False
-					 (current_module st) str)
+       (new_cmstate, maybe_tystr) <- io (cmTypeOfExpr (cmstate st) dflags str)
        setGHCiState st{cmstate = new_cmstate}
-       case maybe_ty of
-	 Nothing -> return ()
-	 Just (_, unqual, ty) -> io (printForUser stdout unqual (ppr ty)) 
+       case maybe_tystr of
+	  Nothing    -> return ()
+	  Just tystr -> io (putStrLn tystr)
 
 quit :: String -> GHCi Bool
 quit _ = return True
@@ -433,7 +474,7 @@ setOptions str
 	      writeIORef v_InitDynFlags dyn_flags
 
               if (not (null leftovers))
-		 then throwDyn (OtherError ("unrecognised flags: " ++ 
+		 then throwDyn (CmdLineError ("unrecognised flags: " ++ 
 						unwords leftovers))
 		 else return ()
          )
@@ -453,7 +494,7 @@ unsetOptions str
  
        -- can't do GHC flags for now
        if (not (null minus_opts))
-	  then throwDyn (OtherError "can't unset GHC command-line flags")
+	  then throwDyn (CmdLineError "can't unset GHC command-line flags")
 	  else return ()
 
 isMinus ('-':s) = True
@@ -484,54 +525,13 @@ optToStr ShowType   = "t"
 optToStr RevertCAFs = "r"
 
 -----------------------------------------------------------------------------
--- Code to do last-expression-entered stuff.  (a.k.a the $$ facility)
-
--- Take a string and replace $$s in it with the last expr, if any.
-expandExpr :: String -> GHCi String
-expandExpr str
-   = do mle <- getLastExpr
-        return (outside mle str)
-     where
-        outside mle ('$':'$':cs)
-           = case mle of
-                Just le -> " (" ++ le ++ ") " ++ outside mle cs
-                Nothing -> outside mle cs
-
-        outside mle []           = []
-        outside mle ('"':str)    = '"' : inside2 mle str   -- "
-        outside mle ('\'':str)   = '\'' : inside1 mle str   -- '
-        outside mle (c:cs)       = c : outside mle cs
-
-        inside2 mle ('"':cs)  = '"' : outside mle cs   -- "
-        inside2 mle (c:cs)    = c : inside2 mle cs
-        inside2 mle []        = []
-
-        inside1 mle ('\'':cs) = '\'': outside mle cs
-        inside1 mle (c:cs)    = c : inside1 mle cs
-        inside1 mle []        = []
-
-
-rememberExpr :: String -> GHCi ()
-rememberExpr str
-   = do let cleaned = (clean . reverse . clean . reverse) str
-        let forget_me_not | null cleaned = Nothing
-                          | otherwise    = Just cleaned
-        setLastExpr forget_me_not
-     where
-        clean = dropWhile isSpace
-
-
------------------------------------------------------------------------------
 -- GHCi monad
 
 data GHCiState = GHCiState
      { 
-	modules	       :: [Module],
-	current_module :: Module,
 	target         :: Maybe FilePath,
 	cmstate        :: CmState,
-	options        :: [GHCiOption],
-        last_expr      :: Maybe String
+	options        :: [GHCiOption]
      }
 
 data GHCiOption 
@@ -540,11 +540,8 @@ data GHCiOption
 	| RevertCAFs		-- revert CAFs after every evaluation
 	deriving Eq
 
-defaultCurrentModuleName = mkModuleName "Prelude"
-GLOBAL_VAR(defaultCurrentModule, error "no defaultCurrentModule", Module)
-
-GLOBAL_VAR(flush_stdout, error "no flush_stdout", HValue)
-GLOBAL_VAR(flush_stderr, error "no flush_stdout", HValue)
+GLOBAL_VAR(flush_stdout, error "no flush_stdout", IO ())
+GLOBAL_VAR(flush_stderr, error "no flush_stdout", IO ())
 
 newtype GHCi a = GHCi { unGHCi :: GHCiState -> IO (GHCiState, a) }
 
@@ -570,14 +567,6 @@ unsetOption opt
  = do st <- getGHCiState
       setGHCiState (st{ options = filter (/= opt) (options st) })
 
-getLastExpr :: GHCi (Maybe String)
-getLastExpr
- = do st <- getGHCiState ; return (last_expr st)
-
-setLastExpr :: Maybe String -> GHCi ()
-setLastExpr last_expr
- = do st <- getGHCiState ; setGHCiState (st{last_expr = last_expr})
-
 io m = GHCi $ \s -> m >>= \a -> return (s,a)
 
 -----------------------------------------------------------------------------
@@ -598,30 +587,84 @@ ghciUnblock (GHCi a) = GHCi $ \s -> Exception.unblock (a s)
 -----------------------------------------------------------------------------
 -- package loader
 
-linkPackages :: [Package] -> IO ()
-linkPackages pkgs = mapM_ linkPackage pkgs
-
-linkPackage :: Package -> IO ()
+-- Left: full path name of a .o file, including trailing .o
+-- Right: "unadorned" name of a .DLL/.so
+--        e.g.    On unix     "qt"  denotes "libqt.so"
+--                On WinDoze  "burble"  denotes "burble.DLL"
+--        addDLL is platform-specific and adds the lib/.so/.DLL
+--        prefixes plaform-dependently; we don't do that here.
+type LibrarySpec
+   = Either FilePath String
+
+showLS (Left nm)  = "(static) " ++ nm
+showLS (Right nm) = "(dynamic) " ++ nm
+
+linkPackages :: [LibrarySpec] -> [PackageConfig] -> IO ()
+linkPackages cmdline_lib_specs pkgs
+   = do mapM_ linkPackage pkgs
+        mapM_ preloadLib cmdline_lib_specs
+     where
+        preloadLib lib_spec
+           = do putStr ("Loading object " ++ showLS lib_spec ++ " ... ")
+                case lib_spec of
+                   Left static_ish
+                      -> do b <- doesFileExist static_ish
+                            if    not b
+                             then do putStr "not found.\n"
+                                     croak
+                             else do loadObj static_ish
+                                     putStr "done.\n"
+                   Right dll_unadorned
+                      -> do maybe_errmsg <- addDLL dll_unadorned
+                            if    maybe_errmsg == nullPtr
+                             then putStr "done.\n"
+                             else do str <- peekCString maybe_errmsg
+                                     putStr ("failed (" ++ str ++ ")\n")
+                                     croak
+
+        croak = throwDyn (CmdLineError "user specified .o/.so/.DLL could not be loaded.")
+
+
+linkPackage :: PackageConfig -> IO ()
 -- ignore rts and gmp for now (ToDo; better?)
-linkPackage pkg | name pkg `elem` ["rts", "gmp"] = return ()
-linkPackage pkg = do
-  putStr ("Loading package " ++ name pkg ++ " ... ")
-  let dirs = library_dirs pkg
-  let objs = map (++".o") (hs_libraries pkg ++ extra_libraries pkg)
-  mapM (linkOneObj dirs) objs
-  putStr "resolving ... "
-  resolveObjs
-  putStrLn "done."
-
-linkOneObj dirs obj = do
-  filename <- findFile dirs obj
-  loadObj filename
-
-findFile [] obj = throwDyn (OtherError ("can't find " ++ obj))
-findFile (d:ds) obj = do
-  let path = d ++ '/':obj
-  b <- doesFileExist path
-  if b then return path else findFile ds obj
+linkPackage pkg 
+   | name pkg `elem` ["rts", "gmp"] 
+   = return ()
+   | otherwise
+   = do putStr ("Loading package " ++ name pkg ++ " ... ")
+        -- For each obj, try obj.o and if that fails, obj.so.
+        -- Complication: all the .so's must be loaded before any of the .o's.  
+        let dirs      =  library_dirs pkg
+        let objs      =  hs_libraries pkg ++ extra_libraries pkg
+        classifieds   <- mapM (locateOneObj dirs) objs
+        let sos_first = filter isRight classifieds 
+                        ++ filter (not.isRight) classifieds
+        mapM loadClassified sos_first
+        putStr "linking ... "
+        resolveObjs
+        putStrLn "done."
+     where
+        isRight (Right _) = True
+        isRight (Left _)  = False
+
+loadClassified :: LibrarySpec -> IO ()
+loadClassified (Left obj_absolute_filename)
+   = do loadObj obj_absolute_filename
+loadClassified (Right dll_unadorned)
+   = do maybe_errmsg <- addDLL dll_unadorned
+        if    maybe_errmsg == nullPtr
+         then return ()
+         else do str <- peekCString maybe_errmsg
+                 throwDyn (CmdLineError ("can't find .o or .so/.DLL for: " 
+                                       ++ dll_unadorned ++ " (" ++ str ++ ")" ))
+
+locateOneObj :: [FilePath] -> String -> IO LibrarySpec
+locateOneObj []     obj 
+   = return (Right obj) -- we assume
+locateOneObj (d:ds) obj 
+   = do let path = d ++ '/':obj ++ ".o"
+        b <- doesFileExist path
+        if b then return (Left path) else locateOneObj ds obj
 
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 -- timing & statistics