From 476a02b6358cc125c0ba31a7db55aa605fea3bdc Mon Sep 17 00:00:00 2001
From: Helmut Merz <helmutm@cy55.de>
Date: Thu, 22 Aug 2013 09:20:57 +0200
Subject: [PATCH] avoid error if section has no parent book

---
 compound/book/view_macros.pt | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/compound/book/view_macros.pt b/compound/book/view_macros.pt
index 43be71b..c5b1562 100644
--- a/compound/book/view_macros.pt
+++ b/compound/book/view_macros.pt
@@ -30,12 +30,13 @@
          tal:attributes="href pred/targetUrl;
                          title pred/title">
         <img src="/@@/cybertools.icons/arrow_left.png" /></a>
-      <a tal:attributes="href parent/targetUrl;
-                          title parent/title">
+      <a tal:condition="nocall:parent"
+         tal:attributes="href parent/targetUrl;
+                         title parent/title">
         <img src="/@@/cybertools.icons/arrow_up.png" /></a>
-      <a  tal:condition="nocall:succ"
-          tal:attributes="href succ/targetUrl;
-                          title succ/title">
+      <a tal:condition="nocall:succ"
+         tal:attributes="href succ/targetUrl;
+                         title succ/title">
         <img src="/@@/cybertools.icons/arrow_right.png" /></a>
     </div>
   </metal:navigation>