--- loncom/homework/matchresponse.pm	2004/02/10 17:01:20	1.36
+++ loncom/homework/matchresponse.pm	2004/03/08 23:23:04	1.37
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # Full matching style response
 #
-# $Id: matchresponse.pm,v 1.36 2004/02/10 17:01:20 albertel Exp $
+# $Id: matchresponse.pm,v 1.37 2004/03/08 23:23:04 albertel Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -30,7 +30,8 @@ package Apache::matchresponse;
 use strict;
 use HTML::Entities();
 use Math::Random();
-use Apache::optionresponse;
+use Apache::optionresponse();
+use Apache::lonlocal;
 
 BEGIN {
     &Apache::lonxml::register('Apache::matchresponse',('matchresponse'));
@@ -46,6 +47,7 @@ sub start_matchresponse {
     push (@Apache::lonxml::namespace,'matchresponse');
     my $id = &Apache::response::start_response($parstack,$safeeval);
     %Apache::hint::match=();
+    undef(%Apache::response::foilnames);
     if ($target eq 'meta') {
 	$result=&Apache::response::meta_package_write('matchresponse');
     } elsif ($target eq 'edit' ) {
@@ -80,6 +82,7 @@ sub end_matchresponse {
     pop @Apache::lonxml::namespace;
     &Apache::lonxml::deregister('Apache::matchresponse',
 				('foilgroup','foil','conceptgroup'));
+    undef(%Apache::response::foilnames);
     return $result;
 }
 
@@ -592,10 +595,14 @@ sub end_foil {
 	my $value = &Apache::lonxml::get_param('value',$parstack,$safeeval);
 	if ($value ne 'unused') {
 	    my $name = &Apache::lonxml::get_param('name',$parstack,$safeeval);
-	    my $location =&Apache::lonxml::get_param('location',$parstack,$safeeval);
 	    &Apache::lonxml::debug("Got a name of :$name:");
 	    if (!$name) { $name=$Apache::lonxml::curdepth; }
 	    &Apache::lonxml::debug("Using a name of :$name:");
+	    if (defined($Apache::response::foilnames{$name})) {
+		&Apache::lonxml::error(&mt("Foil name <b><tt>[_1]</tt></b> appears more than once. Foil names need to be unique.",$name));
+	    }
+	    my $location =&Apache::lonxml::get_param('location',$parstack,
+						     $safeeval);
 	    if ( $Apache::matchresponse::conceptgroup
 		 && !&Apache::response::showallfoils() ) {
 		push @{ $Apache::response::conceptgroup{'names'} }, $name;