Add --ghc-version option

src/Haddock/Options.hs

@@ -84,6 +84,7 @@ data Flag
   | Flag_UsePackage String
   | Flag_OptGhc String
   | Flag_GhcLibDir String
+  | Flag_GhcVersion
   deriving (Eq)
 
 
@@ -152,5 +153,7 @@ options backwardsCompat =
     Option [] ["use-package"] (ReqArg Flag_UsePackage "PACKAGE")
 	"the modules being processed depend on PACKAGE",
     Option [] ["optghc"] (ReqArg Flag_OptGhc "OPTION")
- 	"Forward option to GHC"
+ 	"Forward option to GHC",
+    Option []  ["ghc-version"]  (NoArg Flag_GhcVersion)
+	"output GHC version in numeric format"
    ]

src/Main.hs

@@ -249,8 +249,9 @@ dumpInterfaceFile modules homeLinks flags =
 handleEasyFlags flags fileArgs = do
   usage <- getUsage
 
-  when (Flag_Help    `elem` flags) (bye usage)
-  when (Flag_Version `elem` flags) byeVersion
+  when (Flag_Help       `elem` flags) (bye usage)
+  when (Flag_Version    `elem` flags) byeVersion
+  when (Flag_GhcVersion `elem` flags) byeGhcVersion
   when (null fileArgs) (bye usage)
 
   let ghcLibDir = case [ dir | Flag_GhcLibDir dir <- flags ] of
@@ -267,6 +268,9 @@ handleEasyFlags flags fileArgs = do
       "Haddock version " ++ projectVersion ++ 
       ", (c) Simon Marlow 2003; ported to the GHC-API by David Waern 2006\n"
 
+    byeGhcVersion = bye $ 
+      (fromJust $ lookup "Project version" $ compilerInfo) ++ "\n"
+
 
 updateHTMLXRefs :: [(InterfaceFile, FilePath)] -> IO ()
 updateHTMLXRefs packages = do