Rename Directory to Directory_tree

[dups.git] / dups.ml

diff --git a/dups.ml b/dups.ml
index 0bcc83a..84c0707 100644 (file)
--- a/dups.ml
+++ b/dups.ml
@@ -35,13 +35,12 @@ end = struct
     )
 end
 
-module Directory : sig
+module Directory_tree : sig
   val find_files : string -> string Stream.t
 end = struct
   let find_files root =
     let dirs  = Queue.create () in
     let files = Queue.create () in
-    Queue.add root dirs;
     let explore parent =
       Array.iter (Sys.readdir parent) ~f:(fun child ->
         let path = Filename.concat parent child in
@@ -59,24 +58,16 @@ end = struct
             ()
       )
     in
-    let next_dir () =
-      match Queue.take dirs with
-      | exception Queue.Empty ->
-          ()
-      | dir ->
-          explore dir
+    explore root;
+    let rec next () =
+      match Queue.is_empty files, Queue.is_empty dirs with
+      | false, _     -> Some (Queue.take files)
+      | true , true  -> None
+      | true , false ->
+          explore (Queue.take dirs);
+          next ()
     in
-    let next_file () =
-      match Queue.take files with
-      | exception Queue.Empty ->
-          None
-      | file_path ->
-          Some file_path
-    in
-    Stream.create (fun () ->
-      next_dir ();
-      next_file ()
-    )
+    Stream.create next
 end
 
 type input =
@@ -87,7 +78,7 @@ let main input =
   let paths =
     match input with
     | Paths_on_stdin -> In_channel.lines stdin
-    | Root_path root -> Directory.find_files root
+    | Root_path root -> Directory_tree.find_files root
   in
   let paths_by_digest = Hashtbl.create 1_000_000 in
   let path_count = ref 0 in
@@ -121,5 +112,14 @@ let main input =
 
 let () =
   let input = ref Paths_on_stdin in
-  Arg.parse [] (fun path -> input := Root_path path) "";
+  Arg.parse
+    []
+    (function
+    | path when Sys.file_exists path ->
+        input := Root_path path
+    | path ->
+        eprintf "File does not exist: %S\n%!" path;
+        exit 1
+    )
+    "";
   main !input