-type Finder = ModuleName -> IO (Maybe (Module, ModuleLocation))
-
--- For a module in another package, the hs_file and obj_file
--- components of ModuleLocation are undefined.
-
--- The locations specified by a ModuleLocation may or may not
--- correspond to actual files yet: for example, even if the object
--- file doesn't exist, the ModuleLocation still contains the path to
--- where the object file will reside if/when it is created.
-
-data ModuleLocation
- = ModuleLocation {
- hs_file :: FilePath,
- hi_file :: FilePath,
- obj_file :: FilePath
- }
-
--- caches contents of package directories, never expunged
-GLOBAL_VAR(pkgDirCache, Nothing, Maybe (FiniteMap String (PackageName, FilePath)))
-
--- caches contents of home directories, expunged whenever we
--- create a new finder.
-GLOBAL_VAR(homeDirCache, emptyFM, FiniteMap String FilePath)
-
--- caches finder mapping, expunged whenever we create a new finder.
-GLOBAL_VAR(finderMapCache, emptyFM, FiniteMap ModuleName Module)
-
-
-newFinder :: PackageConfigInfo -> IO Finder
-newFinder (PackageConfigInfo pkgs) = do
- -- expunge our caches
- writeIORef homeDirCache emptyFM
- writeIORef finderMapCache emptyFM
-
- -- populate the home dir cache, using the import path (the import path
- -- is changed by -i flags on the command line, and defaults to ["."]).
- home_imports <- readIORef import_paths
- let extendFM fm path = do
- contents <- getDirectoryContents' path
- return (addListToFM fm (zip contents (repeat path)))
- home_map <- foldM extendFM emptyFM home_imports
- writeIORef homeDirCache home_map
-
- -- populate the package cache, if necessary
- pkg_cache <- readIORef pkgDirCache
- case pkg_cache of
- Nothing -> do
-
- let extendFM fm pkg = do
- let dirs = import_dirs pkg
- pkg_name = _PK_ (name pkg)
- let addDir fm dir = do
- contents <- getDirectoryContents' dir
- return (addListToFM fm (zip contents
- (repeat (pkg_name,dir))))
- foldM addDir fm dirs
-
- pkg_map <- foldM extendFM emptyFM pkgs
- writeIORef pkgDirCache (Just pkg_map)
-
- Just _ ->
- return ()
-
- -- and return the finder
- return finder
-
-
-finder :: ModuleName -> IO (Maybe (Module, ModuleLocation))
-finder name = do
- j <- maybeHomeModule name
- case j of
- Just home_module -> return (Just home_module)
- Nothing -> maybePackageModule name
+
+-- v_PkgDirCache caches contents of package directories, never expunged
+GLOBAL_VAR(v_PkgDirCache, panic "no pkg cache!",
+ FiniteMap String (PackageName, FilePath))
+
+-- v_HomeDirCache caches contents of home directories,
+-- expunged whenever we create a new finder.
+GLOBAL_VAR(v_HomeDirCache, Nothing, Maybe (FiniteMap String FilePath))
+
+
+initFinder :: PackageConfigInfo -> IO ()
+initFinder pkgs
+ = do { -- expunge our home cache
+ ; writeIORef v_HomeDirCache Nothing
+ -- lazilly fill in the package cache
+ ; writeIORef v_PkgDirCache (unsafePerformIO (newPkgCache pkgs))
+ }
+
+emptyHomeDirCache :: IO ()
+emptyHomeDirCache
+ = writeIORef v_HomeDirCache Nothing
+
+findModule :: ModuleName -> IO (Maybe (Module, ModuleLocation))
+findModule name
+ = do { j <- maybeHomeModule name
+ ; case j of
+ Just home_module -> return (Just home_module)
+ Nothing -> maybePackageModule name
+ }