X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=utils%2Frunghc%2Frunghc.hs;h=707dc62be13d767986ba16f40c741fe5f481655b;hb=a6e4ca6e55cfc3f3fd3253df69e803c8a999729a;hp=83163bd401fd706ae162582950d5ca2f09f92ed7;hpb=373b03fe979abe898a387e02ca22007b768e343e;p=ghc-hetmet.git

diff --git a/utils/runghc/runghc.hs b/utils/runghc/runghc.hs
index 83163bd..707dc62 100644
--- a/utils/runghc/runghc.hs
+++ b/utils/runghc/runghc.hs
@@ -11,16 +11,16 @@
 -- runghc program, for invoking from a #! line in a script.  For example:
 --
 --   script.lhs:
---	#! /usr/bin/runghc
---	> main = putStrLn "hello!"
+--      #! /usr/bin/runghc
+--      > main = putStrLn "hello!"
 --
 -- runghc accepts one flag:
 --
---	-f <path>    specify the path
+--      -f <path>    specify the path
 --
 -- -----------------------------------------------------------------------------
 
-module Main where
+module Main (main) where
 
 import System.Environment
 import System.IO
@@ -36,42 +36,68 @@ import System.Cmd       ( rawSystem )
 import System.Directory ( findExecutable )
 #endif
 
-main = do 
-  args <- getArgs
-  case args of
-    ('-':'f' : ghc) : args -> do
-	doIt (dropWhile isSpace ghc) args
-    args -> do
-	mb_ghc <- findExecutable "ghc"
-	case mb_ghc of
-	  Nothing  -> dieProg ("cannot find ghc")
-	  Just ghc -> doIt ghc args
+main :: IO ()
+main = do
+    args <- getArgs
+    case getGhcLoc args of
+        (Just ghc, args') -> doIt ghc args'
+        (Nothing, args') -> do
+            mb_ghc <- findExecutable "ghc"
+            case mb_ghc of
+                Nothing  -> dieProg ("cannot find ghc")
+                Just ghc -> doIt ghc args'
 
+getGhcLoc :: [String] -> (Maybe FilePath, [String])
+getGhcLoc ("-f" : ghc : args) = (Just ghc, args)
+getGhcLoc (('-' : 'f' : ghc) : args) = (Just ghc, args)
+-- If you need the first GHC flag to be a -f flag then you can pass --
+-- first
+getGhcLoc ("--" : args) = (Nothing, args)
+getGhcLoc args = (Nothing, args)
+
+doIt :: String -> [String] -> IO ()
 doIt ghc args = do
-  let
-    (ghc_args, rest) = break notArg args
-  --
-  case rest of
-     [] -> dieProg "syntax: runghc [-f GHCPATH] [GHC-ARGS] FILE ARG..."
-     filename : prog_args -> do
-	  res <- rawSystem ghc (
-			"-ignore-dot-ghci" : ghc_args ++ 
-			[ "-e","System.Environment.withProgName "++show filename++" (System.Environment.withArgs ["
-			  ++ concat (intersperse "," (map show prog_args))
-			  ++ "] (GHC.TopHandler.runIOFastExit Main.main))", filename])
+    let (ghc_args, rest) = getGhcArgs args
+    case rest of
+        [] -> dieProg usage
+        filename : prog_args -> do
+            let expr = "System.Environment.withProgName " ++ show filename ++
+                       " (System.Environment.withArgs " ++ show prog_args ++
+                       " (GHC.TopHandler.runIOFastExit" ++
+                       " (Main.main Prelude.>> Prelude.return ())))"
+            res <- rawSystem ghc (["-ignore-dot-ghci"] ++ ghc_args ++
+                                  [ "-e", expr, filename])
                -- runIOFastExit: makes exceptions raised by Main.main
                -- behave in the same way as for a compiled program.
                -- The "fast exit" part just calls exit() directly
                -- instead of doing an orderly runtime shutdown,
                -- otherwise the main GHCi thread will complain about
                -- being interrupted.
-  	  exitWith res
+               --
+               -- Why (main >> return ()) rather than just main?  Because
+               -- otherwise GHCi by default tries to evaluate the result
+               -- of the IO in order to show it (see #1200).
+            exitWith res
+
+getGhcArgs :: [String] -> ([String], [String])
+getGhcArgs args = case break pastArgs args of
+                      (xs, "--":ys) -> (xs, ys)
+                      (xs, ys)      -> (xs, ys)
 
-notArg ('-':_) = False
-notArg _       = True
+pastArgs :: String -> Bool
+-- You can use -- to mark the end of the flags, in caes you need to use
+-- a file called -foo.hs for some reason. You almost certainly shouldn't,
+-- though.
+pastArgs "--" = True
+pastArgs ('-':_) = False
+pastArgs _       = True
 
 dieProg :: String -> IO a
 dieProg msg = do
-  p <- getProgName
-  hPutStrLn stderr (p ++ ": " ++ msg)
-  exitWith (ExitFailure 1)
+    p <- getProgName
+    hPutStrLn stderr (p ++ ": " ++ msg)
+    exitWith (ExitFailure 1)
+
+usage :: String
+usage = "syntax: runghc [-f GHC-PATH | --] [GHC-ARGS] [--] FILE ARG..."
+