1 files changed, 1 insertions, 1 deletions
diff --git a/src/class.c b/src/class.c
index 92b58c3ff..bdf74e718 100644
--- a/src/class.c
+++ b/src/class.c
@@ -840,7 +840,7 @@ mrb_get_arg1(mrb_state *mrb)
     array_argv = ARY_PTR(a);
   }
   if (argc != 1) {
-    mrb_raise(mrb, E_ARGUMENT_ERROR, "wrong number of arguments");
+    mrb_argnum_error(mrb, argc, 1, 1);
   }
   return array_argv[0];
 }