Safe Haskell	Safe
Language	Haskell2010

System.Directory.Extra

Description

Extra directory functions. Most of these functions provide cleaned up and generalised versions of getDirectoryContents, see listContents for the differences.

Synopsis

Documentation

module System.Directory

withCurrentDirectory :: FilePath -> IO a -> IO a Source

Set the current directory, perform an operation, then change back. Remember that the current directory is a global variable, so calling this function multithreaded is almost certain to go wrong. Avoid changing the current directory if you can.

withTempDir $ \dir -> do writeFile (dir </> "foo.txt") ""; withCurrentDirectory dir $ doesFileExist "foo.txt"

createDirectoryPrivate :: String -> IO () Source

Create a directory with permissions so that only the current user can view it. On Windows this function is equivalent to createDirectory.

listContents :: FilePath -> IO [FilePath] Source

List the files and directories directly within a directory. Each result will be prefixed by the query directory, and the special directories . and .. will be ignored. Intended as a cleaned up version of getDirectoryContents.

withTempDir $ \dir -> do writeFile (dir </> "test.txt") ""; (== [dir </> "test.txt"]) <$> listContents dir
let touch = mapM_ $ \x -> createDirectoryIfMissing True (takeDirectory x) >> writeFile x ""
let listTest op as bs = withTempDir $ \dir -> do touch $ map (dir </>) as; res <- op dir; return $ map (drop (length dir + 1)) res == bs
listTest listContents ["bar.txt","foo/baz.txt","zoo"] ["bar.txt","foo","zoo"]

listFiles :: FilePath -> IO [FilePath] Source

Like listContents, but only returns the files in a directory, not other directories. Each file will be prefixed by the query directory.

listTest listFiles ["bar.txt","foo/baz.txt","zoo"] ["bar.txt","zoo"]

listFilesInside :: (FilePath -> IO Bool) -> FilePath -> IO [FilePath] Source

Like listFilesRecursive, but with a predicate to decide where to recurse into. Typically directories starting with . would be ignored. The initial argument directory will have the test applied to it.

listTest (listFilesInside $ return . not . isPrefixOf "." . takeFileName)
    ["bar.txt","foo" </> "baz.txt",".foo" </> "baz2.txt", "zoo"] ["bar.txt","zoo","foo" </> "baz.txt"]
listTest (listFilesInside $ const $ return False) ["bar.txt"] []

listFilesRecursive :: FilePath -> IO [FilePath] Source

Like listFiles, but goes recursively through all subdirectories. This function will follow symlinks, and if they form a loop, this function will not terminate.

listTest listFilesRecursive ["bar.txt","zoo","foo" </> "baz.txt"] ["bar.txt","zoo","foo" </> "baz.txt"]