creating src/Boot.hs.

src/Boot.hs

@@ -0,0 +1,42 @@
+module Boot where
+
+import Language.Haskell.GhcMod
+import Control.Applicative ((<$>))
+
+boot :: Options -> Cradle -> IO String
+boot opt cradle = do
+    mods  <- listModules opt cradle
+    langs <- listLanguages opt
+    flags <- listFlags opt
+    let opt' = addPackages opt
+    pre   <- concat <$> mapM (browseModule opt' cradle) preBrowsedModules
+    return $ mods ++ langs ++ flags ++ pre
+
+preBrowsedModules :: [String]
+preBrowsedModules = [
+    "Prelude"
+  , "Control.Applicative"
+  , "Control.Exception"
+  , "Control.Monad"
+  , "Data.ByteString"
+  , "Data.Char"
+  , "Data.List"
+  , "Data.Maybe"
+  , "System.Directory"
+  , "System.FilePath"
+  , "System.IO"
+  ]
+
+preBrowsePackages :: [String]
+preBrowsePackages = [
+    "bytestring"
+  , "directory"
+  , "filepath"
+  ]
+
+addPackages :: Options -> Options
+addPackages opt = opt { ghcOpts = pkgs ++ ghcOpts opt}
+  where
+    pkgs = map ("-package " ++) preBrowsePackages
+
+