From 9e181ddc6536db9aba3370a32558e8c8cacdf0cd Mon Sep 17 00:00:00 2001
From: Milan <mc@radiopiloten.de>
Date: Mon, 28 Dec 2020 14:23:14 +0100
Subject: [PATCH] series.cgi: remove undef warnings

---
 website/agenda/planung/series.cgi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/website/agenda/planung/series.cgi b/website/agenda/planung/series.cgi
index ba7ae71..e5c23f2 100755
--- a/website/agenda/planung/series.cgi
+++ b/website/agenda/planung/series.cgi
@@ -1075,7 +1075,7 @@ sub show_series {
     my $serie = $series->[0];
 
     uac::print_error( 'Predecessor must be different from series id.' ) 
-        if $serie->{predecessor_id} eq $serie->{series_id};
+        if $serie->{predecessor_id}//'' eq $serie->{series_id};
 
     #get all users currently assigned to the user
     my $user_studios =