Fixing a harmless warning in debug mode.

diff --git a/mod/lesson/lib.php b/mod/lesson/lib.php
index 7f9259139594cc20b2bb4c5c8fa7e99a28a22d14..208fc8d54a9e56abd95bf2cce7712e9acaf71468 100644 (file)
--- a/mod/lesson/lib.php
+++ b/mod/lesson/lib.php
@@ -321,7 +321,7 @@ function lesson_grades($lessonid) {
        if (!$lesson = get_record("lesson", "id", $lessonid)) {
                error("Lesson record not found");
        }
-    if ($lesson->usemaxgrade) {
+    if (!empty($lesson->usemaxgrade)) {
         $grades = get_records_sql_menu("SELECT userid,MAX(grade) FROM {$CFG->prefix}lesson_grades WHERE
                 lessonid = $lessonid GROUP BY userid");
     } else {