--- loncom/interface/spreadsheet/Spreadsheet.pm	2003/10/11 14:04:54	1.28
+++ loncom/interface/spreadsheet/Spreadsheet.pm	2003/11/17 19:55:41	1.30
@@ -1,5 +1,5 @@
 #
-# $Id: Spreadsheet.pm,v 1.28 2003/10/11 14:04:54 www Exp $
+# $Id: Spreadsheet.pm,v 1.30 2003/11/17 19:55:41 matthew Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -678,7 +678,7 @@ sub calc {
             return $lastcalc.': Maximum calculation depth exceeded';
         }
     }
-    return '';
+    return 'okay';
 }
 
 # ------------------------------------------- End of "Inside of the safe space"
@@ -1139,9 +1139,49 @@ sub calcsheet {
 #    $self->logthis($self->get_errorlog());
     %{$self->{'values'}} = %{$self->{'safe'}->varglob('sheet_values')};
 #    $self->logthis($self->get_errorlog());
+    if ($result ne 'okay') {
+        $self->set_calcerror($result);
+    }
     return $result;
 }
 
+sub set_badcalc {
+    my $self = shift();
+    $self->{'badcalc'} =1;
+    return;
+}
+
+sub badcalc {
+    my $self = shift;
+    if (exists($self->{'badcalc'}) && $self->{'badcalc'}) {
+        return 1;
+    } else {
+        return 0;
+    }
+}
+
+sub set_calcerror {
+    my $self = shift;
+    if (@_) {
+        $self->set_badcalc();
+        if (exists($self->{'calcerror'})) {
+            $self->{'calcerror'}.="\n".$_[0];
+        } else {
+            $self->{'calcerror'}.=$_[0];
+        }
+    }
+}
+
+sub calcerror {
+    my $self = shift;
+    if ($self->badcalc()) {
+        if (exists($self->{'calcerror'})) {
+            return $self->{'calcerror'};
+        }
+    }
+    return;
+}
+
 ###########################################################
 ##
 ## Output Helpers
@@ -1169,6 +1209,18 @@ sub display {
 ############################################
 ##         HTML output routines           ##
 ############################################
+sub html_report_error {
+    my $self = shift();
+    my $Str = '';
+    if ($self->badcalc()) {
+        $Str = '<h3 style="color:red">'.
+            &mt('An error occurred while calculating this spreadsheet').
+            "</h3>\n".
+            '<pre>'.$self->calcerror()."</pre>\n";
+    }
+    return $Str;
+}
+
 sub html_export_row {
     my $self = shift();
     my ($color) = @_;
@@ -1283,7 +1335,7 @@ sub html_header {
     my $self = shift;
     return '' if (! $ENV{'request.role.adv'});
     return "<table>\n".
-        '<tr><th align="center">'.&mt('Output Format').'</th><tr>'."\n".
+        '<tr><th align="center">'.&mt('Output Format').'</th></tr>'."\n".
         '<tr><td>'.&output_selector()."</td></tr>\n".
         "</table>\n";
 }
@@ -1618,6 +1670,9 @@ sub set_row_numbers {
 ##
 sub exportrow {
     my $self = shift;
+    if (exists($self->{'badcalc'}) && $self->{'badcalc'}) {
+        return ();
+    }
     my @exportarray;
     foreach my $column (@UC_Columns) {
         push(@exportarray,$self->value($column.'0'));