diff --git a/patch.sh b/patch.sh
index 907225b..2a7550a 100755
--- a/patch.sh
+++ b/patch.sh
@@ -79,7 +79,7 @@ fi
 
 echo "Detected nvidia driver version: $driver_version"
 
-if [[ ! -v "patch_list[$driver_version]" || ! -v "object_list[$driver_version]" ]]; then
+if [[ ! "${patch_list[$driver_version]+isset}" || ! "${object_list[$driver_version]+isset}" ]]; then
     echo "Patch for this ($driver_version) nvidia driver not found." 1>&2
     echo "Available patches for: " 1>&2
     for drv in "${!patch_list[@]}"; do