Update fileStream.hs

fileStream.hs

@@ -1,7 +1,9 @@
 --  Copyright © 2025 Hashirama Senju
 {-
-    this is an extremely fast and memory-constant program that lists directories in recursive mode;
+    this is an extremely fast and memory-constant program that lists mdx files in directories in recursive mode;
     the output is utf8, so that it can display japanese characters.
+
+    notice that you can remove the filter and generalize this to search for any file that you want.
 -}
 
 {-# LANGUAGE OverloadedStrings #-}
@@ -12,11 +14,13 @@ import Pipes.Safe
 import System.IO (stdout, hSetEncoding, utf8)
 import qualified Data.Text as T
 import qualified Data.Text.IO as TIO
-import Filesystem.Path.CurrentOS (encodeString)
+import Filesystem.Path.CurrentOS (encodeString, extension)
+import Control.Monad (when)
 
 main :: IO ()
 main = do
     hSetEncoding stdout utf8
     runSafeT $ runEffect $
-        for (every (descendentOf "/mnt/Data/Japanese_Resources/")) $
-            liftIO . TIO.putStrLn . T.pack . encodeString
+        for (every (descendentOf "/mnt/Data/Japanese_Resources/")) $ \fp ->
+            when (extension fp == Just "mdx") $
+                liftIO $ TIO.putStrLn $ T.pack $ encodeString fp