[7489] check for existence of string

[gavinsmith0123]

Revision: 7489
          http://svn.sv.gnu.org/viewvc/?view=rev&root=texinfo&revision=7489
Author:   gavin
Date:     2016-11-01 11:50:17 +0000 (Tue, 01 Nov 2016)
Log Message:
-----------
check for existence of string

Modified Paths:
--------------
    trunk/ChangeLog
    trunk/tp/Texinfo/Convert/HTML.pm

Modified: trunk/ChangeLog
===================================================================
--- trunk/ChangeLog     2016-11-01 11:20:36 UTC (rev 7488)
+++ trunk/ChangeLog     2016-11-01 11:50:17 UTC (rev 7489)
@@ -1,5 +1,10 @@
 2016-11-01  Gavin Smith  <address@hidden>
 
+       * tp/Texinfo/Convert/HTML.pm (output): Check for existence of a 
+       string before testing equality.
+
+2016-11-01  Gavin Smith  <address@hidden>
+
        Experimental change to reduce use of normalized labels.
 
        * tp/Texinfo/Parser.pm (_register_label): For @float's only,

Modified: trunk/tp/Texinfo/Convert/HTML.pm
===================================================================
--- trunk/tp/Texinfo/Convert/HTML.pm    2016-11-01 11:20:36 UTC (rev 7488)
+++ trunk/tp/Texinfo/Convert/HTML.pm    2016-11-01 11:50:17 UTC (rev 7489)
@@ -7077,7 +7077,8 @@
       # NOTE 'node_filename' is not used for Top, so the other manual
       # must use the same convention to get it right.  We avoid doing
       # also 'node_filename' to avoid unneeded redirection files.
-      if ($node->{'extra'}->{'normalized'} eq 'Top' 
+      if ($node->{'extra'} and $node->{'extra'}->{'normalized'}
+          and $node->{'extra'}->{'normalized'} eq 'Top' 
           and defined($self->get_conf('TOP_NODE_FILE_TARGET'))) {
         my $extension = '';
         $extension = "." . $self->get_conf('NODE_FILE_EXTENSION')