diff --git a/day4.ml b/day4.ml
index 99aecaf..33b885b 100644
--- a/day4.ml
+++ b/day4.ml
@@ -105,9 +105,8 @@ module Validators = struct
 
   let year_range lo hi x =
     x =~? {|^\d{4}$|} &&
-    match int_of_string x with
-    | exception Invalid_argument _ -> false
-    | x -> x >= lo && x <= hi
+    let x = int_of_string x in
+    x >= lo && x <= hi
 
   let%test _ = year_range 1900 2000 "1950"
   let%test _ = year_range 1900 2000 "1900"