--- loncom/homework/grades.pm	2010/12/04 15:02:26	1.639
+++ loncom/homework/grades.pm	2011/05/27 14:39:50	1.648
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # The LON-CAPA Grading handler
 #
-# $Id: grades.pm,v 1.639 2010/12/04 15:02:26 www Exp $
+# $Id: grades.pm,v 1.648 2011/05/27 14:39:50 bisitz Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -40,7 +40,7 @@ use Apache::lonhomework;
 use Apache::lonpickcode;
 use Apache::loncoursedata;
 use Apache::lonmsg();
-use Apache::Constants qw(:common);
+use Apache::Constants qw(:common :http);
 use Apache::lonlocal;
 use Apache::lonenc;
 use Apache::lonstathelpers;
@@ -213,8 +213,13 @@ sub reset_caches {
     }
 
     sub get_analyze {
-	my ($symb,$uname,$udom,$no_increment,$add_to_hash)=@_;
+	my ($symb,$uname,$udom,$no_increment,$add_to_hash,$type,$trial,$rndseed)=@_;
 	my $key = "$symb\0$uname\0$udom";
+        if ($type eq 'randomizetry') {
+            if ($trial ne '') {
+                $key .= "\0".$trial;
+            }
+        }
 	if (exists($analyze_cache{$key})) {
             my $getupdate = 0;
             if (ref($add_to_hash) eq 'HASH') {
@@ -242,9 +247,15 @@ sub reset_caches {
                     'grade_courseid'    =>  $env{'request.course.id'},
                     'grade_username'    => $uname,
                     'grade_noincrement' => $no_increment);
+        if ($type eq 'randomizetry') {
+            $form{'grade_questiontype'} = $type;
+            if ($rndseed ne '') {
+                $form{'grade_rndseed'} = $rndseed;
+            }
+        }
         if (ref($add_to_hash)) {
             %form = (%form,%{$add_to_hash});
-        } 
+        }
 	my $subresult=&ssi_with_retries($url, $ssi_retries,%form);
 	(undef,$subresult)=split(/_HASH_REF__/,$subresult,2);
 	my %analyze=&Apache::lonnet::str2hash($subresult);
@@ -257,15 +268,15 @@ sub reset_caches {
     }
 
     sub get_order {
-	my ($partid,$respid,$symb,$uname,$udom,$no_increment)=@_;
-	my $analyze = &get_analyze($symb,$uname,$udom,$no_increment);
+	my ($partid,$respid,$symb,$uname,$udom,$no_increment,$type,$trial,$rndseed)=@_;
+	my $analyze = &get_analyze($symb,$uname,$udom,$no_increment,undef,$type,$trial,$rndseed);
 	return $analyze->{"$partid.$respid.shown"};
     }
 
     sub get_radiobutton_correct_foil {
-	my ($partid,$respid,$symb,$uname,$udom)=@_;
-	my $analyze = &get_analyze($symb,$uname,$udom);
-        my $foils = &get_order($partid,$respid,$symb,$uname,$udom);
+	my ($partid,$respid,$symb,$uname,$udom,$type,$trial,$rndseed)=@_;
+	my $analyze = &get_analyze($symb,$uname,$udom,undef,undef,$type,$trial,$rndseed);
+        my $foils = &get_order($partid,$respid,$symb,$uname,$udom,undef,$type,$trial,$rndseed);
         if (ref($foils) eq 'ARRAY') {
 	    foreach my $foil (@{$foils}) {
 	        if ($analyze->{"$partid.$respid.foil.value.$foil"} eq 'true') {
@@ -307,7 +318,7 @@ sub reset_caches {
 #        response types only.
 sub cleanRecord {
     my ($answer,$response,$symb,$partid,$respid,$record,$order,$version,
-	$uname,$udom) = @_;
+	$uname,$udom,$type,$trial,$rndseed) = @_;
     my $grayFont = '<span class="LC_internal_info">';
     if ($response =~ /^(option|rank)$/) {
 	my %answer=&Apache::lonnet::str2hash($answer);
@@ -351,7 +362,7 @@ sub cleanRecord {
 	my %answer=&Apache::lonnet::str2hash($answer);
 	my ($toprow,$bottomrow);
 	my $correct = 
-	    &get_radiobutton_correct_foil($partid,$respid,$symb,$uname,$udom);
+	    &get_radiobutton_correct_foil($partid,$respid,$symb,$uname,$udom,$type,$trial,$rndseed);
 	foreach my $foil (@$order) {
 	    if (exists($answer{$foil})) {
 		if ($foil eq $correct) {
@@ -1501,7 +1512,7 @@ INNERJS
     var ypos = (screen.height-height)/2-30;
     ypos = (ypos < 0) ? '0' : ypos;
 
-    pWin = window.open('', 'MessageCenter', 'resizable=yes,toolbar=no,location=no,scrollbars='+scrollbar+',screenx='+xpos+',screeny='+ypos+',width=600,height='+height);
+    pWin = window.open('', 'MessageCenter', 'resizable=yes,toolbar=no,location=no,scrollbars='+scrollbar+',screenx='+xpos+',screeny='+ypos+',width=700,height='+height);
     pWin.focus();
     pDoc = pWin.document;
     pDoc.$docopen;
@@ -2133,6 +2144,12 @@ KEYWORDS
 		    my ($ressub,$hide,$subval) = split(/:/,$submission,3);
 		    # Similarity check
 		    my $similar='';
+                    my ($type,$trial,$rndseed);
+                    if ($hide eq 'rand') {
+                        $type = 'randomizetry';
+                        $trial = $record{"resource.$partid.tries"};
+                        $rndseed = $record{"resource.$partid.rndseed"};
+                    }
 		    if($env{'form.checkPlag'}){
 			my ($oname,$odom,$ocrsid,$oessay,$osim)=
 			    &most_similar($uname,$udom,$subval,\%old_essays);
@@ -2142,7 +2159,7 @@ KEYWORDS
 				&Apache::lonnet::coursedescription($ocrsid,
 								   {'one_time' => 1});
 
-                            if ($hide) {
+                            if ($hide eq 'anon') {
                                 $similar='<hr /><span class="LC_warning">'.&mt("Essay was found to be similar to another essay submitted for this assignment.").'<br />'.
                                          &mt('As the current submission is for an anonymous survey, no other details are available.').'</span><hr />';
                             } else {
@@ -2159,7 +2176,8 @@ KEYWORDS
                             }
 			}
 		    }
-		    my $order=&get_order($partid,$respid,$symb,$uname,$udom);
+		    my $order=&get_order($partid,$respid,$symb,$uname,$udom,
+                                         undef,$type,$trial,$rndseed);
 		    if ($env{'form.lastSub'} eq 'lastonly' || 
 			($env{'form.lastSub'} eq 'hdgrade' && 
 			 $$handgrade{$$part[0].'_'.$$part[1]} eq 'yes')) {
@@ -2171,7 +2189,7 @@ KEYWORDS
                             '</span>&nbsp; &nbsp;';
 			my $files=&get_submitted_files($udom,$uname,$partid,$respid,\%record);
 			if (@$files) {
-                            if ($hide) {
+                            if ($hide eq 'anon') {
                                 $lastsubonly.='<br />'.&mt('[quant,_1,file] uploaded to this anonymous survey',scalar(@{$files}));
                             } else {
                                 $lastsubonly.='<br /><span class="LC_warning">'.&mt('Like all files provided by users, this file may contain viruses').'</span><br />';
@@ -2182,12 +2200,12 @@ KEYWORDS
                             }
 			    $lastsubonly.='<br />';
 			}
-                        if ($hide) {
+                        if ($hide eq 'anon') {
                             $lastsubonly.='<b>'.&mt('Anonymous Survey').'</b>'; 
                         } else {
 			    $lastsubonly.='<b>'.&mt('Submitted Answer:').' </b>'.
 			        &cleanRecord($subval,$responsetype,$symb,$partid,
-					     $respid,\%record,$order,undef,$uname,$udom);
+					     $respid,\%record,$order,undef,$uname,$udom,$type,$trial,$rndseed);
                         }
 			if ($similar) {$lastsubonly.="<br /><br />$similar\n";}
 			$lastsubonly.='</div>';
@@ -2386,35 +2404,51 @@ sub get_last_submission {
 		    &Apache::lonlocal::locallocaltime($$returnhash{$version.':timestamp'});
 	    }
 	}
-        my %typeparts;
+        my (%typeparts,%randombytry);
         my $showsurv = 
             &Apache::lonnet::allowed('vas',$env{'request.course.id'});
         foreach my $key (sort(keys(%lasthash))) {
             if ($key =~ /\.type$/) {
                 if (($lasthash{$key} eq 'anonsurvey') || 
-                    ($lasthash{$key} eq 'anonsurveycred')) {
+                    ($lasthash{$key} eq 'anonsurveycred') ||
+                    ($lasthash{$key} eq 'randomizetry')) {
                     my ($ign,@parts) = split(/\./,$key);
                     pop(@parts);
-                    unless ($showsurv) {
-                        my $id = join(',',@parts);
-                        $typeparts{$ign.'.'.$id} = $lasthash{$key};
+                    my $id = join('.',@parts);
+                    if ($lasthash{$key} eq 'randomizetry') {
+                        $randombytry{$ign.'.'.$id} = $lasthash{$key};
+                    } else {
+                        unless ($showsurv) {
+                            $typeparts{$ign.'.'.$id} = $lasthash{$key};
+                        }
                     }
                     delete($lasthash{$key});
                 }
             }
         }
         my @hidden = keys(%typeparts);
+        my @randomize = keys(%randombytry);
 	foreach my $key (keys(%lasthash)) {
 	    next if ($key !~ /\.submission$/);
             my $hide;
             if (@hidden) {
                 foreach my $id (@hidden) {
                     if ($key =~ /^\Q$id\E/) {
-                        $hide = 1;
+                        $hide = 'anon';
                         last;
                     }
                 }
             }
+            unless ($hide) {
+                if (@randomize) {
+                    foreach my $id (@hidden) {
+                        if ($key =~ /^\Q$id\E/) {
+                            $hide = 'rand';
+                            last;
+                        }
+                    }
+                }
+            }
 	    my ($partid,$foo) = split(/submission$/,$key);
 	    my $draft  = $lasthash{$partid.'awarddetail'} eq 'DRAFT' ?
 		'<span class="LC_warning">Draft Copy</span> ' : '';
@@ -4366,8 +4400,8 @@ sub displayPage {
 		&Apache::loncommon::start_data_table_row().
 		'<td align="center" valign="top" >'.$prob.
 		(scalar(@{$parts}) == 1 ? '' 
-		                        : '<br />('.&mt('[_1]&nbsp;parts)',
-							scalar(@{$parts}))
+		                        : '<br />('.&mt('[_1]parts)',
+							scalar(@{$parts}).'&nbsp;')
 		 ).
 		 '</td>';
 	    $studentTable.='<td valign="top">';
@@ -4461,6 +4495,7 @@ sub displaySubByDates {
 
     my $interaction;
     my $no_increment = 1;
+    my %lastrndseed;
     for ($version=1;$version<=$$record{'version'};$version++) {
 	my $timestamp = 
 	    &Apache::lonlocal::locallocaltime($$record{$version.':timestamp'});
@@ -4478,9 +4513,9 @@ sub displaySubByDates {
 	my @versionKeys = split(/\:/,$$record{$version.':keys'});
 	my @displaySub = ();
 	foreach my $partid (@{$parts}) {
-            my $hidden;
-            if (($$record{$version.':resource.'.$partid.'.type'} eq 'anonsurvey') ||
-                ($$record{$version.':resource.'.$partid.'.type'} eq 'anonsurveycred')) {
+            my ($hidden,$type);
+            $type = $$record{$version.':resource.'.$partid.'.type'};
+            if (($type eq 'anonsurvey') || ($type eq 'anonsurveycred')) {
                 $hidden = 1;
             }
 	    my @matchKey = ($isTask ? sort(grep /^resource\.\d+\.\Q$partid\E\.award$/,@versionKeys)
@@ -4503,23 +4538,34 @@ sub displaySubByDates {
                     if ($hidden) {
                         $displaySub[0].= &mt('Anonymous Survey').'</b>';
                     } else {
+                        my ($trial,$rndseed,$newvariation);
+                        if ($type eq 'randomizetry') {
+                            $trial = $$record{"$where.$partid.tries"};
+                            $rndseed = $$record{"$where.$partid.rndseed"};
+                        }
 		        if ($$record{"$where.$partid.tries"} eq '') {
 			    $displaySub[0].=&mt('Trial not counted');
 		        } else {
 			    $displaySub[0].=&mt('Trial: [_1]',
 					    $$record{"$where.$partid.tries"});
+                            if ($rndseed || $lastrndseed{$partid}) {
+                                if ($rndseed ne $lastrndseed{$partid}) {
+                                    $newvariation = '&nbsp;('.&mt('New variation this try').')';
+                                }
+                            }
+                            $lastrndseed{$partid} = $rndseed;
 		        }
 		        my $responseType=($isTask ? 'Task'
                                               : $responseType->{$partid}->{$responseId});
 		        if (!exists($orders{$partid})) { $orders{$partid}={}; }
-		        if (!exists($orders{$partid}->{$responseId})) {
+		        if ((!exists($orders{$partid}->{$responseId})) || ($trial)) {
 			    $orders{$partid}->{$responseId}=
 			        &get_order($partid,$responseId,$symb,$uname,$udom,
-                                           $no_increment);
+                                           $no_increment,$type,$trial,$rndseed);
 		        }
-		        $displaySub[0].='</b></span>'; # /nobreak
+		        $displaySub[0].='</b>'.$newvariation.'</span>'; # /nobreak
 		        $displaySub[0].='&nbsp; '.
-			    &cleanRecord($$record{$version.':'.$matchKey},$responseType,$symb,$partid,$responseId,$record,$orders{$partid}->{$responseId},"$version:",$uname,$udom).'<br />';
+			    &cleanRecord($$record{$version.':'.$matchKey},$responseType,$symb,$partid,$responseId,$record,$orders{$partid}->{$responseId},"$version:",$uname,$udom,$type,$trial,$rndseed).'<br />';
                     }
 		}
 	    }
@@ -4618,7 +4664,7 @@ sub updateGradeByPage {
 		&Apache::loncommon::start_data_table_row().
 		'<td align="center" valign="top" >'.$prob.
 		(scalar(@{$parts}) == 1 ? '' 
-                                        : '<br />('.&mt('[quant,_1,&nbsp;part]',scalar(@{$parts}))
+                                        : '<br />('.&mt('[quant,_1,part]',scalar(@{$parts}))
 		.')').'</td>';
 	    $studentTable.='<td valign="top">&nbsp;<b>'.$title.'</b>&nbsp;</td>';
 
@@ -6153,15 +6199,15 @@ sub scantron_do_warning {
     if ( $env{'form.selectpage'} eq '' ||
 	 $env{'form.scantron_selectfile'} eq '' ||
 	 $env{'form.scantron_format'} eq '' ) {
-	$r->print("<p>".&mt('You have forgetten to specify some information. Please go Back and try again.')."</p>");
+	$r->print("<p>".&mt('You have forgotten to specify some information. Please go Back and try again.')."</p>");
 	if ( $env{'form.selectpage'} eq '') {
 	    $r->print('<p><span class="LC_error">'.&mt('You have not selected a Sequence to grade').'</span></p>');
 	} 
 	if ( $env{'form.scantron_selectfile'} eq '') {
-	    $r->print('<p><span class="LC_error">'.&mt('You have not selected a file that contains the student\'s response data.').'</span></p>');
+	    $r->print('<p><span class="LC_error">'.&mt("You have not selected a file that contains the student's response data.").'</span></p>');
 	} 
 	if ( $env{'form.scantron_format'} eq '') {
-	    $r->print('<p><span class="LC_error">'.&mt('You have not selected a the format of the student\'s response data.').'</span></p>');
+	    $r->print('<p><span class="LC_error">'.&mt("You have not selected the format of the student's response data.").'</span></p>');
 	} 
     } else {
 	my $warning=&scantron_warning_screen('Grading: Validate Records');
@@ -7838,7 +7884,7 @@ sub scantron_upload_scantron_data {
 
 '));
     $r->print('
-<h3>'.&mt('Send scanned bubblesheet data to a course').'</h3>
+<h3>'.&mt('Send bubblesheet data to a course').'</h3>
 
 <form enctype="multipart/form-data" action="/adm/grades" name="rules" method="post">
 '.$default_form_data.
@@ -8176,7 +8222,15 @@ sub checkscantron_results {
             }
         }
     }
-    $r->print('<p>'.&mt('Comparison of bubblesheet data (including corrections) with corresponding submission records (most recent submission) for <b>[quant,_1,student]</b>  ([_2] scantron lines/student).',$numstudents,$env{'form.scantron_maxbubble'}).'</p>');
+    $r->print(
+        '<p>'
+       .&mt('Comparison of bubblesheet data (including corrections) with corresponding submission records (most recent submission) for [_1][quant,_2,student][_3] ([quant,_4,bubblesheet line] per student).',
+            '<b>',
+            $numstudents,
+            '</b>',
+            $env{'form.scantron_maxbubble'})
+       .'</p>'
+    );
     $r->print('<p>'.&mt('Exact matches for <b>[quant,_1,student]</b>.',$passed).'<br />'.&mt('Discrepancies detected for <b>[quant,_1,student]</b>.',$failed).'</p>');
     if ($passed) {
         $r->print(&mt('Students with exact correspondence between bubblesheet data and submissions are as follows:').'<br /><br />');
@@ -8431,7 +8485,7 @@ sub grading_menu {
                     		url => $url4,
                     		permission => 'F',
                     		icon => 'bubblesheet.png',
-                    		linktitle => 'Grade scantron exams, upload/download scantron data files, and review previously graded scantron exams.'
+                    		linktitle => 'Grade bubblesheet exams, upload/download bubblesheet data files, and review previously graded bubblesheet exams.'
                 	    },
                             {   linktext => 'Verify Receipt Number',
                                 url => $url5,
@@ -8795,7 +8849,7 @@ sub process_clicker_file {
     if ($env{'form.gradingmechanism'} eq 'given') {
         $env{'form.givenanswer'}=~s/^\s*//gs;
         $env{'form.givenanswer'}=~s/\s*$//gs;
-        $env{'form.givenanswer'}=~s/[^a-zA-Z0-9\.\*\-]+/\,/g;
+        $env{'form.givenanswer'}=~s/[^a-zA-Z0-9\.\*\-\+]+/\,/g;
         $env{'form.givenanswer'}=uc($env{'form.givenanswer'});
         my @answers=split(/\,/,$env{'form.givenanswer'});
         $foundgiven=$#answers+1;
@@ -8927,7 +8981,7 @@ ENDHEADER
                    "\n".&mt("Username").": <input type='text' name='uname".$id."' />&nbsp;".
                    "\n".&mt("Domain").": ".
                    &Apache::loncommon::select_dom_form($env{'course.'.$env{'request.course.id'}.'.domain'},'udom'.$id).'&nbsp;'.
-                   &Apache::loncommon::selectstudent_link('clickeranalysis','uname'.$id,'udom'.$id);
+                   &Apache::loncommon::selectstudent_link('clickeranalysis','uname'.$id,'udom'.$id,0,$id);
           $unknown_count++;
        }
     }
@@ -8973,6 +9027,7 @@ sub iclicker_eval {
 	    $id=~s/^[\#0]+//;
 	    for (my $i=0;$i<$number;$i++) {
 		my $idx=3+$i*6;
+                $entries[$idx]=~s/[^a-zA-Z0-9\.\*\-\+]+//g;
 		push(@idresponses,$entries[$idx]);
 	    }
 	    $$responses{$id}=join(',',@idresponses);
@@ -9044,20 +9099,20 @@ sub assign_clicker_grades {
                     $result.='<br /><span class="LC_warning">'.
                              &mt('More than one correct result given for question "[_1]": [_2] versus [_3].',
                                  $env{'form.question:'.$i},$correct[$i],$input[$i]).'</span>';
-                 } elsif ($input[$i]) {
+                 } elsif (($input[$i]) || ($input[$i] eq '0')) {
                     $correct[$i]=$input[$i];
                  }
              }
           }
        }
        for (my $i=0;$i<$number;$i++) {
-          if (!$correct[$i]) {
+          if ((!$correct[$i]) && ($correct[$i] ne '0')) {
              $result.='<br /><span class="LC_error">'.
                       &mt('No correct result given for question "[_1]"!',
                           $env{'form.question:'.$i}).'</span>';
           }
        }
-       $result.='<br />'.&mt("Correct answer: [_1]",join(', ',map { ($_?$_:'-') } @correct));
+       $result.='<br />'.&mt("Correct answer: [_1]",join(', ',map { ((($_) || ($_ eq '0'))?$_:'-') } @correct));
     }
 # Start grading
     my $pcorrect=$env{'form.pcorrect'};
@@ -9090,17 +9145,29 @@ sub assign_clicker_grades {
           for (my $i=0;$i<$number;$i++) {
              if  ($correct[$i] eq '-') {
                 $realnumber--;
-             } elsif ($answer[$i]) {
+             } elsif (($answer[$i]) || ($answer[$i]=~/^[0\.]+$/))  {
                 if ($gradingmechanism eq 'attendance') {
                    $sum+=$pcorrect;
                 } elsif ($correct[$i] eq '*') {
                    $sum+=$pcorrect;
                 } else {
-                   if ($answer[$i] eq $correct[$i]) {
-                      $sum+=$pcorrect;
-                   } else {
-                      $sum+=$pincorrect;
+# We actually grade if correct or not
+                   my $increment=$pincorrect;
+# Special case: numerical answer "0"
+                   if ($correct[$i] eq '0') {
+                      if ($answer[$i]=~/^[0\.]+$/) {
+                         $increment=$pcorrect;
+                      }
+# General numerical answer, both evaluate to something non-zero
+                   } elsif ((1.0*$correct[$i]!=0) && (1.0*$answer[$i]!=0)) {
+                      if (1.0*$correct[$i]==1.0*$answer[$i]) {
+                         $increment=$pcorrect;
+                      }
+# Must be just alphanumeric
+                   } elsif ($answer[$i] eq $correct[$i]) {
+                      $increment=$pcorrect;
                    }
+                   $sum+=$increment;
                 }
              }
           }
@@ -9141,7 +9208,7 @@ sub startpage {
     unshift(@$crumbs,{href=>&href_symb_cmd($symb,'gradingmenu'),text=>"Grading"});
     $r->print(&Apache::loncommon::start_page('Grading',undef,
                                           {'bread_crumbs' => $crumbs}));
-    &Apache::lonquickgrades::startGradeScreen($r,'grading');
+    &Apache::lonquickgrades::startGradeScreen($r,($env{'form.symb'}?'probgrading':'grading'));
     unless ($nodisplayflag) {
        $r->print(&Apache::lonhtmlcommon::resource_info_box($symb,$onlyfolderflag));
     }
@@ -9158,15 +9225,25 @@ sub select_problem {
 sub handler {
     my $request=$_[0];
     &reset_caches();
-    if ($env{'browser.mathml'}) {
-	&Apache::loncommon::content_type($request,'text/xml');
-    } else {
-	&Apache::loncommon::content_type($request,'text/html');
+    if ($request->header_only) {
+        &Apache::loncommon::content_type($request,'text/html');
+        $request->send_http_header;
+        return OK;
     }
-    $request->send_http_header;
-    return '' if $request->header_only;
     &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'});
 
+    &init_perm();
+    if (!$env{'request.course.id'}) {
+        # Not in a course.
+        $env{'user.error.msg'}="/adm/grades::vgr:0:0:Cannot display grades page outside course context";
+        return HTTP_NOT_ACCEPTABLE;
+    } elsif (!%perm) {
+        $request->internal_redirect('/adm/quickgrades');
+    }
+    &Apache::loncommon::content_type($request,'text/html');
+    $request->send_http_header;
+
+
 # see what command we need to execute
 
     my @commands=&Apache::loncommon::get_env_multiple('form.command');
@@ -9183,7 +9260,7 @@ sub handler {
        (my $url=$env{'form.url'}) =~ s-^https*://($ENV{'SERVER_NAME'}|$ENV{'HTTP_HOST'})--;
        $symb=&Apache::lonnet::symbread($url);
     }
-    &Apache::lonenc::check_decrypt(\$symb);                             
+    &Apache::lonenc::check_decrypt(\$symb);
 
     $ssi_error = 0;
     if (($symb eq '' || $command eq '') && ($env{'request.course.id'})) {
@@ -9193,7 +9270,6 @@ sub handler {
         &startpage($request,undef,[],1,1);
         &select_problem($request);
     } else {
-	&init_perm();
 	if ($command eq 'submission' && $perm{'vgr'}) {
             &startpage($request,$symb,[{href=>"", text=>"Student Submissions"}]);
 	    ($env{'form.student'} eq '' ? &listStudents($request,$symb) : &submission($request,0,0,$symb));
@@ -9337,7 +9413,7 @@ sub handler {
     &Apache::lonquickgrades::endGradeScreen($request);
     $request->print(&Apache::loncommon::end_page());
     &reset_caches();
-    return '';
+    return OK;
 }
 
 1;