, exitWith -- :: ExitCode -> IO a
, exitFailure -- :: IO a
) where
+\end{code}
-#ifdef __HUGS__
-import PreludeBuiltin
-
-indexAddrOffAddr = primIndexAddrOffAddr
-
-unpackCString = unsafeUnpackCString
-#else
+#ifndef __HUGS__
+\begin{code}
import Prelude
import PrelAddr
import PrelIOBase ( IOError(..), IOErrorType(..), constructErrorAndFailWithInfo, stToIO )
import PrelPack ( unpackCString, unpackCStringST, packString )
-import PrelArr ( ByteArray )
+import PrelByteArr ( ByteArray )
type PrimByteArray = ByteArray Int
primPackString :: String -> PrimByteArray
primPackString s = packString s
-#endif
\end{code}
de_slash _acc ('/':xs) = de_slash [] xs
de_slash acc (x:xs) = de_slash (x:acc) xs
\end{code}
+
+#else
+
+\begin{code}
+-----------------------------------------------------------------------------
+-- Standard Library: System operations
+--
+-- Warning: the implementation of these functions in Hugs 98 is very weak.
+-- The functions themselves are best suited to uses in compiled programs,
+-- and not to use in an interpreter-based environment like Hugs.
+--
+-- Suitable for use with Hugs 98
+-----------------------------------------------------------------------------
+import PrelPrim ( primGetRawArgs
+ , primGetEnv
+ , prelCleanupAfterRunAction
+ , copy_String_to_cstring
+ , readIORef
+ , nh_stderr
+ , nh_stdout
+ , nh_stdin
+ , nh_exitwith
+ , nh_flush
+ , nh_close
+ , nh_system
+ , nh_free
+ , nh_getPID
+ )
+
+
+data ExitCode = ExitSuccess | ExitFailure Int
+ deriving (Eq, Ord, Read, Show)
+
+getArgs :: IO [String]
+getArgs = primGetRawArgs >>= \rawargs ->
+ return (tail rawargs)
+
+getProgName :: IO String
+getProgName = primGetRawArgs >>= \rawargs ->
+ return (head rawargs)
+
+getEnv :: String -> IO String
+getEnv = primGetEnv
+
+exitFailure :: IO a
+exitFailure = exitWith (ExitFailure 1)
+
+toExitCode :: Int -> ExitCode
+toExitCode 0 = ExitSuccess
+toExitCode n = ExitFailure n
+
+fromExitCode :: ExitCode -> Int
+fromExitCode ExitSuccess = 0
+fromExitCode (ExitFailure n) = n
+
+-- see comment in Prelude.hs near primRunIO_hugs_toplevel
+exitWith :: ExitCode -> IO a
+exitWith c
+ = do cleanup_action <- readIORef prelCleanupAfterRunAction
+ case cleanup_action of
+ Just xx -> xx
+ Nothing -> return ()
+ nh_stderr >>= nh_flush
+ nh_stdout >>= nh_flush
+ nh_stdin >>= nh_close
+ nh_exitwith (fromExitCode c)
+ (ioError.IOError) "System.exitWith: should not return"
+
+system :: String -> IO ExitCode
+system cmd
+ | null cmd
+ = (ioError.IOError) "System.system: null command"
+ | otherwise
+ = do str <- copy_String_to_cstring cmd
+ status <- nh_system str
+ nh_free str
+ case status of
+ 0 -> return ExitSuccess
+ n -> return (ExitFailure n)
+
+getPID :: IO Int
+getPID
+ = nh_getPID
+
+-----------------------------------------------------------------------------
+\end{code}
+#endif