diff --git a/src/proto/typval.pro b/src/proto/typval.pro
index 102821d..ad20f8c 100644
--- a/src/proto/typval.pro
+++ b/src/proto/typval.pro
@@ -9,8 +9,8 @@
 varnumber_T tv_get_bool(typval_T *varp);
 varnumber_T tv_get_bool_chk(typval_T *varp, int *denote);
 float_T tv_get_float(typval_T *varp);
-int check_for_string(typval_T *tv, int arg);
-int check_for_nonempty_string(typval_T *tv, int arg);
+int check_for_string_arg(typval_T *args, int idx);
+int check_for_nonempty_string_arg(typval_T *args, int idx);
 char_u *tv_get_string(typval_T *varp);
 char_u *tv_get_string_strict(typval_T *varp);
 char_u *tv_get_string_buf(typval_T *varp, char_u *buf);