--- loncom/xml/lonxml.pm	2002/01/07 18:11:57	1.146
+++ loncom/xml/lonxml.pm	2002/06/14 19:56:57	1.177
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # XML Parser Module 
 #
-# $Id: lonxml.pm,v 1.146 2002/01/07 18:11:57 albertel Exp $
+# $Id: lonxml.pm,v 1.177 2002/06/14 19:56:57 www Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -60,15 +60,16 @@
 
 package Apache::lonxml; 
 use vars 
-qw(@pwd @outputstack $redirection $import @extlinks $metamode $evaluate %insertlist @namespace);
+qw(@pwd @outputstack $redirection $import @extlinks $metamode $evaluate %insertlist @namespace $prevent_entity_encode);
 use strict;
-use HTML::TokeParser;
-use HTML::TreeBuilder;
-use Safe;
-use Safe::Hole;
-use Math::Cephes qw(:trigs :hypers :bessels erf erfc);
-use Math::Random qw(:all);
-use Opcode;
+use HTML::LCParser();
+use HTML::TreeBuilder();
+use HTML::Entities();
+use Safe();
+use Safe::Hole();
+use Math::Cephes();
+use Math::Random();
+use Opcode();
 
 sub register {
   my ($space,@taglist) = @_;
@@ -89,15 +90,15 @@ sub deregister {
 }
 
 use Apache::Constants qw(:common);
-use Apache::lontexconvert;
-use Apache::style;
-use Apache::run;
-use Apache::londefdef;
-use Apache::scripttag;
-use Apache::edit;
-use Apache::lonnet;
-use Apache::File;
-use Apache::loncommon;
+use Apache::lontexconvert();
+use Apache::style();
+use Apache::run();
+use Apache::londefdef();
+use Apache::scripttag();
+use Apache::edit();
+use Apache::lonnet();
+use Apache::File();
+use Apache::loncommon();
 
 #==================================================   Main subroutine: xmlparse  
 #debugging control, to turn on debugging modify the correct handler
@@ -128,9 +129,15 @@ $evaluate = 1;
 # stores the list of active tag namespaces
 @namespace=();
 
+# if 0 all high ASCII characters will be encoded into HTML Entities
+$prevent_entity_encode=0;
+
 # has the dynamic menu been updated to know about this resource
 $Apache::lonxml::registered=0;
 
+# a pointer the the Apache request object
+$Apache::lonxml::request='';
+
 sub xmlbegin {
   my $output='';
   if ($ENV{'browser.mathml'}) {
@@ -175,10 +182,12 @@ sub xmlend {
                   }
                   my $sender='Anonymous';
                   if ((!$contrib{$idx.':anonymous'}) || ($seeid)) {
-                      $sender=$contrib{$idx.':sendername'}.' at '.
-		      $contrib{$idx.':senderdomain'};
+                      $sender=$contrib{$idx.':plainname'}.' ('.
+                              $contrib{$idx.':sendername'}.' at '.
+		      $contrib{$idx.':senderdomain'}.')';
                       if ($contrib{$idx.':anonymous'}) {
-			  $sender.=' (anonymous)';
+			  $sender.=' [anonymous] '.
+                                     $contrib{$idx.':screenname'};
                       }
                       if ($seeid) {
 			  if ($hidden) {
@@ -189,6 +198,10 @@ sub xmlend {
 				 $symb.':::'.$idx.'">Hide</a>';
 			  }
                       }                   
+                  } else {
+                      if ($contrib{$idx.':screenname'}) {
+			  $sender='<i>'.$contrib{$idx.':screenname'}.'</i>';
+                      }
                   }
 		  $discussion.='<p><b>'.$sender.'</b> ('.
                       localtime($contrib{$idx.':timestamp'}).
@@ -316,46 +329,49 @@ sub fontsettings() {
 
 sub registerurl {
     my $forcereg=shift;
-    if ($ENV{'request.publicaccess'}) {
+    my $target = shift;
+    my $result = '';
+    if ((($ENV{'request.publicaccess'}) || 
+         (!&Apache::lonnet::is_on_map($ENV{'REQUEST_URI'}))) &&
+        (!$forcereg)) {
 	return 
          '<script>function LONCAPAreg(){} function LONCAPAstale(){}</script>';
     }
     if ($Apache::lonxml::registered && !$forcereg) { return ''; }
     $Apache::lonxml::registered=1;
+    my $nothing='';
+    if ($ENV{'browser.type'} eq 'explorer') { $nothing='javascript:void(0);'; }
+    my $timesync='menu.clock.setTime(1000*'.time.');';
     if (($ENV{'REQUEST_URI'}!~/^\/(res\/)*adm\//) || ($forcereg)) {
         my $hwkadd='';
-        if ($ENV{'REQUEST_URI'}=~/\.(problem|exam|quiz|assess|survey|form)$/) {
+        if ($ENV{'request.filename'}=~/\.(problem|exam|quiz|assess|survey|form)$/) {
 	    if (&Apache::lonnet::allowed('vgr',$ENV{'request.course.id'})) {
 		$hwkadd.=(<<ENDSUBM);
-                     menu.switchbutton
-           (7,1,'subm.gif','view sub','missions',
-                'gocmd("/adm/grades","submission")');
+                     menu.switchbutton(7,1,'subm.gif','view sub','missions','gocmd("/adm/grades","submission")');
 ENDSUBM
             }
 	    if (&Apache::lonnet::allowed('mgr',$ENV{'request.course.id'})) {
 		$hwkadd.=(<<ENDGRDS);
-                     menu.switchbutton
-           (7,2,'pgrd.gif','problem','grades',
-                'gocmd("/adm/grades","viewgrades")');
+                     menu.switchbutton(7,2,'pgrd.gif','problem','grades','gocmd("/adm/grades","gradingmenu")');
 ENDGRDS
             }
 	    if (&Apache::lonnet::allowed('opa',$ENV{'request.course.id'})) {
 		$hwkadd.=(<<ENDPARM);
-                     menu.switchbutton
-           (7,3,'pparm.gif','problem','parms',
-                'gocmd("/adm/parmset","set")');
+                     menu.switchbutton(7,3,'pparm.gif','problem','parms','gocmd("/adm/parmset","set")');
 ENDPARM
             }
 	}
-	return (<<ENDREGTHIS);
+	$result = (<<ENDREGTHIS);
      
 <script language="JavaScript">
 // BEGIN LON-CAPA Internal
 
     function LONCAPAreg() {
-	  menu=window.open("","LONCAPAmenu");
+	  menu=window.open("$nothing","LONCAPAmenu","",false);
           menu.clearTimeout(menu.menucltim);
+          $timesync
 	  menu.currentURL=window.location.pathname;
+          menu.reloadURL=window.location.pathname;
           menu.currentStale=0;
           menu.clearbut(3,1);
           menu.switchbutton
@@ -380,10 +396,12 @@ ENDPARM
     }
 
     function LONCAPAstale() {
-	  menu=window.open("","LONCAPAmenu");
+	  menu=window.open("$nothing","LONCAPAmenu","",false);
           menu.currentStale=1;
-          menu.switchbutton
-             (3,1,'reload.gif','return','location','go(currentURL)');
+          if (menu.reloadURL!='' && menu.reloadURL!= null) { 
+             menu.switchbutton
+             (3,1,'reload.gif','return','location','go(reloadURL)');
+	  }
           menu.clearbut(7,1);
           menu.clearbut(7,2);
           menu.clearbut(7,3);
@@ -399,13 +417,14 @@ ENDPARM
 ENDREGTHIS
 
     } else {
-        return (<<ENDDONOTREGTHIS);
+        $result = (<<ENDDONOTREGTHIS);
 
 <script language="JavaScript">
 // BEGIN LON-CAPA Internal
 
     function LONCAPAreg() {
-	  menu=window.open("","LONCAPAmenu");
+	  menu=window.open("$nothing","LONCAPAmenu","",false);
+          $timesync
           menu.currentStale=1;
           menu.clearbut(2,1);
           menu.clearbut(2,3);
@@ -426,8 +445,63 @@ ENDREGTHIS
 // END LON-CAPA Internal
 </script>
 ENDDONOTREGTHIS
-
     }
+    if ($target eq 'edit') {
+	# Javascript routines for construction space:
+	# openbrowser and opensearcher will start the file browser
+	# (lonindexer) and searcher (lonsearchcat) respectively.
+	# Inputs are the name of the html form being used
+	# and the name of the element the selected URL should
+	# be placed in.
+        # openbrowser also takes arguments only and omit, which are
+        # comma deliminated lists of file extensions to (only) show 
+        # or omit.
+        # Here we also set currentURL=null.
+        $result .=<<"ENDBROWSERSCRIPT";
+<script>
+    menu.currentURL=null;
+    var editbrowser;
+    function openbrowser(formname,elementname,only,omit) {
+        var url = '/res/?';
+        if (editbrowser == null) {
+            url += 'launch=1&';
+        }
+        url += 'catalogmode=interactive&';
+        url += 'mode=edit&';
+        url += 'form=' + formname + '&';
+        if (only != null) {
+            url += 'only=' + only + '&';
+        } 
+        if (omit != null) {
+            url += 'omit=' + omit + '&';
+        }
+        url += 'element=' + elementname + '';
+        var title = 'Browser';
+        var options = 'scrollbars=1,resizable=1,menubar=0';
+        options += ',width=700,height=600';
+        editbrowser = open(url,title,options,'1');
+        editbrowser.focus();
+    }
+    var editsearcher;
+    function opensearcher(formname,elementname) {
+        var url = '/adm/searchcat?';
+        if (editsearcher == null) {
+            url += 'launch=1&';
+        }
+        url += 'catalogmode=interactive&';
+        url += 'mode=edit&';
+        url += 'form=' + formname + '&';
+        url += 'element=' + elementname + '';
+        var title = 'Search';
+        var options = 'scrollbars=1,resizable=1,menubar=0';
+        options += ',width=700,height=600';
+        editsearcher = open(url,title,options,'1');
+        editsearcher.focus();
+    }
+</script>
+ENDBROWSERSCRIPT
+    }
+    return $result;
 }
 
 sub loadevents() {
@@ -447,9 +521,9 @@ sub printalltags {
 }
 
 sub xmlparse {
- my ($target,$content_file_string,$safeinit,%style_for_target) = @_;
+ my ($request,$target,$content_file_string,$safeinit,%style_for_target) = @_;
 
- &setup_globals($target);
+ &setup_globals($request,$target);
  #&printalltags();
  my @pars = ();
  my $pwd=$ENV{'request.filename'};
@@ -463,7 +537,7 @@ sub xmlparse {
 
  ($target, my @tenta) = split('&&',$target);
 
- my @stack = (); 
+ my @stack = ();
  my @parstack = ();
  &initdepth;
 
@@ -485,7 +559,7 @@ sub htmlclean {
 
     my $output= $tree->as_HTML(undef,' ');
 
-    $output=~s/\<(br|hr|img|meta|allow)([^\>\/]*)\>/\<$1$2 \/\>/gis;
+    $output=~s/\<(br|hr|img|meta|allow)(.*?)\>/\<$1$2 \/\>/gis;
     $output=~s/\<\/(br|hr|img|meta|allow)\>//gis;
     unless ($full) {
        $output=~s/\<[\/]*(body|head|html)\>//gis;
@@ -533,8 +607,14 @@ sub inner_xmlparse {
       } elsif ($token->[0] eq 'E') {
 	#clear out any tags that didn't end
 	while ($token->[1] ne $$stack['-1'] && ($#$stack > -1)) {
-	  &Apache::lonxml::warning('Missing tag &lt;/'.$$stack['-1'].'&gt; in file');
-	  &end_tag($stack,$parstack,$token);
+	  my $lasttag=$$stack[-1];
+	  if ($token->[1] =~ /^$lasttag$/i) {
+	    &Apache::lonxml::warning('Using tag &lt;/'.$token->[1].'&gt; as end tag to &lt;'.$$stack[-1].'&gt;');
+	    last;
+	  } else {
+	    &Apache::lonxml::warning('Found tag &lt;/'.$token->[1].'&gt; when looking for &lt;/'.$$stack[-1].'&gt; in file');
+	    &end_tag($stack,$parstack,$token);
+	  }
 	}
 
 	if (exists($$style_for_target{'/'."$token->[1]"})) {
@@ -557,18 +637,22 @@ sub inner_xmlparse {
       #evaluate variable refs in result
       if ($result ne "") {
 	if ( $#$parstack > -1 ) {
-	  if ($Apache::lonxml::redirection) {
-	    $Apache::lonxml::outputstack['-1'] .= 
-	      &Apache::run::evaluate($result,$safeeval,$$parstack['-1']);
-	  } else {
-	    $finaloutput .= &Apache::run::evaluate($result,$safeeval,
-						   $$parstack['-1']);
-	  }
+	  $result=&Apache::run::evaluate($result,$safeeval,$$parstack[-1]);
 	} else {
-	  $finaloutput .= &Apache::run::evaluate($result,$safeeval,'');
+	  $result= &Apache::run::evaluate($result,$safeeval,'');
 	}
-	$result = '';
-      } 
+      }
+      # Encode any high ASCII characters
+      if (!$Apache::lonxml::prevent_entity_encode) {
+	$result=&HTML::Entities::encode($result,"\200-\377");
+      }
+      if ($Apache::lonxml::redirection) {
+	$Apache::lonxml::outputstack['-1'] .= $result;
+      } else {
+	$finaloutput.=$result;
+      }
+      $result = '';
+
       if ($token->[0] eq 'E') { 
 	&end_tag($stack,$parstack,$token);
       }
@@ -581,6 +665,7 @@ sub inner_xmlparse {
   #   $finaloutput.=&endredirection;
   # }
 
+
   if (($ENV{'QUERY_STRING'}) && ($target eq 'web')) {
     $finaloutput=&afterburn($finaloutput);
   }
@@ -613,10 +698,16 @@ sub recurse {
 			       $safeeval, $style_for_target);
       } elsif ($tokenpat->[0] eq 'E') {
 	#clear out any tags that didn't end
-	while ($tokenpat->[1] ne $innerstack[$#innerstack] 
+	while ($tokenpat->[1] ne $innerstack[$#innerstack]
 	       && ($#innerstack > -1)) {
-	  &Apache::lonxml::warning('Missing tag &lt;/'.$innerstack['-1'].'&gt; in style');
-	  &end_tag(\@innerstack,\@innerparstack,$tokenpat);
+	  my $lasttag=$innerstack[-1];
+	  if ($tokenpat->[1] =~ /^$lasttag$/i) {
+	    &Apache::lonxml::warning('Using tag &lt;/'.$tokenpat->[1].'&gt; as end tag to &lt;'.$innerstack[-1].'&gt;');
+	    last;
+	  } else {
+	    &Apache::lonxml::warning('Found tag &lt;/'.$tokenpat->[1].'&gt; when looking for &lt;/'.$innerstack[-1].'&gt; in file');
+	    &end_tag(\@innerstack,\@innerparstack,$tokenpat);
+	  }
 	}
 	$partstring = &callsub("end_$tokenpat->[1]", $target, $tokenpat,
 			       \@innerstack, \@innerparstack, \@pat,
@@ -677,13 +768,13 @@ sub callsub {
     }
     if (!$deleted) {
       if ($space) {
-	#&Apache::lonxml::debug("Calling sub $sub in $space $metamode<br />\n");
+	#&Apache::lonxml::debug("Calling sub $sub in $space $metamode");
 	$sub1="$space\:\:$sub";
 	($currentstring,$nodefault) = &$sub1($target,$token,$tagstack,
 					     $parstack,$parser,$safeeval,
 					     $style);
       } else {
-	#&Apache::lonxml::debug("NOT Calling sub $sub in $space $metamode<br />\n");
+	#&Apache::lonxml::debug("NOT Calling sub $sub in $space $metamode");
 	if ($metamode <1) {
 	  if (defined($token->[4]) && ($metamode < 1)) {
 	    $currentstring = $token->[4];
@@ -717,7 +808,8 @@ sub callsub {
 }
 
 sub setup_globals {
-  my ($target)=@_;
+  my ($request,$target)=@_;
+  $Apache::lonxml::request=$request;
   $Apache::lonxml::registered = 0;
   @Apache::lonxml::pwd=();
   @Apache::lonxml::extlinks=();
@@ -746,6 +838,11 @@ sub setup_globals {
     $Apache::lonxml::metamode = 0;
     $Apache::lonxml::evaluate = 0;
     $Apache::lonxml::import = 0;
+  } elsif ($target eq 'analyze') {
+    $Apache::lonxml::redirection = 0;
+    $Apache::lonxml::metamode = 0;
+    $Apache::lonxml::evaluate = 1;
+    $Apache::lonxml::import = 1;
   } else {
     $Apache::lonxml::redirection = 0;
     $Apache::lonxml::metamode = 0;
@@ -885,10 +982,10 @@ sub get_all_text {
      } elsif ($token->[0] eq 'PI') {
        $result.=$token->[2];
      } elsif ($token->[0] eq 'S') {
-       if ($token->[1] eq $tag) { $depth++; }
+       if ($token->[1] =~ /^$tag$/i) { $depth++; }
        $result.=$token->[4];
      } elsif ($token->[0] eq 'E')  {
-       if ( $token->[1] eq $tag) { $depth--; }
+       if ( $token->[1] =~ /^$tag$/i) { $depth--; }
        #skip sending back the last end tag
        if ($depth > -1) { $result.=$token->[2]; } else {
 	 $pars->unget_token($token);
@@ -903,7 +1000,7 @@ sub get_all_text {
      } elsif ($token->[0] eq 'PI') {
        $result.=$token->[2];
      } elsif ($token->[0] eq 'S') {
-       if ( $token->[1] eq $tag) { 
+       if ( $token->[1] =~ /^$tag$/i) {
 	 $pars->unget_token($token); last;
        } else {
 	 $result.=$token->[4];
@@ -919,7 +1016,7 @@ sub get_all_text {
 
 sub newparser {
   my ($parser,$contentref,$dir) = @_;
-  push (@$parser,HTML::TokeParser->new($contentref));
+  push (@$parser,HTML::LCParser->new($contentref));
   $$parser['-1']->xml_mode('1');
   if ( $dir eq '' ) {
     push (@Apache::lonxml::pwd, $Apache::lonxml::pwd[$#Apache::lonxml::pwd]);
@@ -936,7 +1033,7 @@ sub parstring {
   foreach (@{$token->[3]}) {
     unless ($_=~/\W/) {
       my $val=$token->[2]->{$_};
-      $val =~ s/([\%\@\\])/\\$1/g;
+      $val =~ s/([\%\@\\\"])/\\$1/g;
       #if ($val =~ m/^[\%\@]/) { $val="\\".$val; }
       $temp .= "my \$$_=\"$val\";"
     }
@@ -966,16 +1063,8 @@ sub writeallows {
 #
 sub afterburn {
     my $result=shift;
-    foreach (split(/&/,$ENV{'QUERY_STRING'})) {
-       my ($name, $value) = split(/=/,$_);
-       $value =~ tr/+/ /;
-       $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C",hex($1))/eg;
-       if (($name eq 'highlight')||($name eq 'anchor')||($name eq 'link')) {
-           unless ($ENV{'form.'.$name}) {
-              $ENV{'form.'.$name}=$value;
-	   }
-       }
-    }
+    &Apache::loncommon::get_unprocessed_cgi($ENV{'QUERY_STRING'},
+					    ['highlight','anchor','link']);
     if ($ENV{'form.highlight'}) {
        foreach (split(/\,/,$ENV{'form.highlight'})) {
            my $anchorname=$_;
@@ -1011,13 +1100,13 @@ sub storefile {
     if (my $fh=Apache::File->new('>'.$file)) {
 	print $fh $contents;
         $fh->close();
+    } else {
+      &warning("Unable to save file $file");
     }
 }
 
-sub inserteditinfo {
-      my ($result,$filecontents)=@_;
-      unless ($filecontents) {
-	  $filecontents=(<<SIMPLECONTENT);
+sub createnewhtml {
+  my $filecontents=(<<SIMPLECONTENT);
 <html>
 <head>
 <title>
@@ -1031,28 +1120,67 @@ sub inserteditinfo {
 </body>
 </html>
 SIMPLECONTENT
-      }
-      my $editheader='<a href="#editsection">Edit below</a><hr />';
+  return $filecontents;
+}
+
+
+sub inserteditinfo {
+      my ($result,$filecontents)=@_;
+      $filecontents = &HTML::Entities::encode($filecontents);
+#      my $editheader='<a href="#editsection">Edit below</a><hr />';
+      my $buttons=(<<BUTTONS);
+<input type="submit" name="attemptclean" 
+       value="Save and then attempt to clean HTML" />
+<input type="submit" name="savethisfile" value="Save this" />
+<input type="submit" name="viewmode" value="View" />
+BUTTONS
       my $editfooter=(<<ENDFOOTER);
 <hr />
 <a name="editsection" />
 <form method="post">
+<input type="hidden" name="editmode" value="Edit" />
+$buttons<br />
 <textarea cols="80" rows="40" name="filecont">$filecontents</textarea>
+<br />$buttons
 <br />
-<input type="submit" name="attemptclean" 
-       value="Save and then attempt to clean HTML" />
-<input type="submit" name="savethisfile" value="Save this" />
 </form>
 ENDFOOTER
-      $result=~s/(\<body[^\>]*\>)/$1$editheader/is;
+#      $result=~s/(\<body[^\>]*\>)/$1$editheader/is;
       $result=~s/(\<\/body\>)/$editfooter/is;
       return $result;
 }
 
+sub get_target {
+  my $viewgrades=&Apache::lonnet::allowed('vgr',$ENV{'request.course.id'});
+  if ( $ENV{'request.state'} eq 'published') {
+    if ( defined($ENV{'form.grade_target'})
+	 && ($viewgrades == 'F' )) {
+      return ($ENV{'form.grade_target'});
+    } elsif (defined($ENV{'form.grade_target'})) {
+      if (($ENV{'form.grade_target'} eq 'web') ||
+	  ($ENV{'form.grade_target'} eq 'tex') ) {
+	return $ENV{'form.grade_target'}
+      } else {
+	return 'web';
+      }
+    } else {
+      return 'web';
+    }
+  } elsif ($ENV{'request.state'} eq 'construct') {
+    if ( defined($ENV{'form.grade_target'})) {
+      return ($ENV{'form.grade_target'});
+    } else {
+      return 'web';
+    }
+  } else {
+    return 'web';
+  }
+}
+
 sub handler {
   my $request=shift;
 
-  my $target='web';
+  my $target=&get_target();
 
   $Apache::lonxml::debug=0;
 
@@ -1077,7 +1205,7 @@ sub handler {
       }
   }
   my %mystyle;
-  my $result = ''; 
+  my $result = '';
   my $filecontents=&Apache::lonnet::getfile($file);
   if ($filecontents == -1) {
     $result=(<<ENDNOTFOUND);
@@ -1091,29 +1219,42 @@ sub handler {
 </html>
 ENDNOTFOUND
     $filecontents='';
+    if ($ENV{'request.state'} ne 'published') {
+      $filecontents=&createnewhtml();
+      $ENV{'form.editmode'}='Edit'; #force edit mode
+    }
   } else {
-      unless ($ENV{'request.state'} eq 'published') {
-         if ($ENV{'form.attemptclean'}) {
-	    $filecontents=&htmlclean($filecontents,1);
-         }
+    unless ($ENV{'request.state'} eq 'published') {
+      if ($ENV{'form.attemptclean'}) {
+	$filecontents=&htmlclean($filecontents,1);
       }
-    $result = &Apache::lonxml::xmlparse($target,$filecontents,'',%mystyle);
+    }
+    if (!$ENV{'form.editmode'} || $ENV{'form.viewmode'}) {
+      $result = &Apache::lonxml::xmlparse($request,$target,$filecontents,
+					  '',%mystyle);
+    }
   }
 
 #
 # Edit action? Insert editing commands
 #
   unless ($ENV{'request.state'} eq 'published') {
+    if ($ENV{'form.editmode'} && (!($ENV{'form.viewmode'}))) {
+	my $displayfile=$request->uri;
+        $displayfile=~s/^\/[^\/]*//;
+      $result='<html><body bgcolor="#FFFFFF"><h3>'.$displayfile.
+              '</h3></body></html>';
       $result=&inserteditinfo($result,$filecontents);
+    }
   }
-  
+
   writeallows($request->uri);
 
   $request->print($result);
 
   return OK;
 }
- 
+
 sub debug {
   if ($Apache::lonxml::debug eq 1) {
     $|=1;
@@ -1123,7 +1264,8 @@ sub debug {
 
 sub error {
   if (($Apache::lonxml::debug eq 1) || ($ENV{'request.state'} eq 'construct') ) {
-    print "<b>ERROR:</b>".join('<br />',@_)."<br />\n";
+    # If printing in construction space, put the error inside <pre></pre>
+    print "<b>ERROR:</b>".join("\n",@_)."\n";
   } else {
     print "<b>An Error occured while processing this resource. The instructor has been notified.</b> <br />";
     #notify author
@@ -1156,6 +1298,7 @@ sub get_param {
   if ( ! $context ) { $context = -1; }
   my $args ='';
   if ( $#$parstack > (-2-$context) ) { $args=$$parstack[$context]; }
+  if ( ! $args ) { return undef; }
   if ( $args =~ /my \$$param=\"/ ) {
     return &Apache::run::run("{$args;".'return $'.$param.'}',$safeeval); #'
   } else {