002/104: dirname

README.md

@@ -4,6 +4,8 @@
   <img src="https://www.maizure.org/projects/decoded-gnu-coreutils/GNU.png" />
   <br />
   <img src="https://www.haskell.org/img/haskell-logo.svg" />
+  <br />
+  <br />
 </div>
 
 # Description

src/dirname.hs

@@ -0,0 +1,19 @@
+{-# LANGUAGE NoImplicitPrelude #-}
+{-# LANGUAGE OverloadedStrings #-}
+
+import Prelude            (IO, String, (.), (==), mapM_, putStrLn)
+import Control.Monad      ((>>=))
+import System.Environment (getArgs)
+import Data.Text          (Text, breakOnEnd, dropWhileEnd, pack, unpack)
+
+dropFilename :: (Text, Text) -> Text
+dropFilename ("", "")     = "."
+dropFilename ("", file)   = file
+dropFilename (dir, _file) = dropWhileEnd (== '/') dir
+
+dirname :: String -> String
+dirname = unpack . dropFilename . breakOnEnd "/" . pack
+
+main :: IO ()
+main = getArgs >>= mapM_ (putStrLn . dirname)
+