lec 05 notes

lecture05/number_file_lines.ml

@@ -0,0 +1,16 @@
+let rec number acc ic =
+  try
+    Printf.printf "%5d| %s\n" acc @@ input_line ic;
+    number (acc + 1) ic
+  with
+  | _ -> if ic <> stdin then close_in ic else ()
+
+let () =
+  if Array.length Sys.argv = 1 then
+    number 1 stdin
+  else
+    try
+      number 1 @@ open_in Sys.argv.(1)
+    with
+    | Sys_error s -> Printf.eprintf "%s\n" s;;
+