--- loncom/xml/lontexconvert.pm	2006/05/30 12:47:53	1.75
+++ loncom/xml/lontexconvert.pm	2006/10/23 18:49:47	1.79
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # TeX Conversion Module
 #
-# $Id: lontexconvert.pm,v 1.75 2006/05/30 12:47:53 www Exp $
+# $Id: lontexconvert.pm,v 1.79 2006/10/23 18:49:47 albertel Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -176,28 +176,33 @@ sub jsMath_converted {
 }
 
 {
-    my $jsMath_sent_header;
+    my @jsMath_sent_header;
     sub jsMath_reset {
-	$jsMath_sent_header=0;
+	undef(@jsMath_sent_header);
+    }
+    sub jsMath_push {
+	push(@jsMath_sent_header,0);
     }
     sub jsMath_header {
-	return '' if $jsMath_sent_header;
-	$jsMath_sent_header=1;
+	return '' if $jsMath_sent_header[-1];
+	$jsMath_sent_header[-1]=1;
 	return
             '<script type="text/javascript">
                      function NoFontMessage () {}
+                     jsMath = {Parser: {prototype: {environments: {\'eqnarray*\' :[\'Array\',null,null,\'rcl\',[5/18,5/18],3,\'D\']}}}};
                    </script>'."\n".
 	    '<script type="text/javascript" src="/adm/jsMath/jsMath.js"></script>'."\n";
     }
     sub jsMath_process {
-	return '' if !$jsMath_sent_header;
+	my $state = pop(@jsMath_sent_header);
+	return '' if !$state;
 	return '<script type="text/javascript">jsMath.Process()</script>';
     }
 }
 
 sub init_math_support {
     &init_tth();
-    &Apache::lontexconvert::jsMath_reset();
+    &Apache::lontexconvert::jsMath_push();
     if ($env{'environment.texengine'} eq 'jsMath' ||
 	$env{'form.texengine'}        eq 'jsMath' ) {
 	return &Apache::lontexconvert::jsMath_header();
@@ -262,8 +267,8 @@ sub smiley {
 		 '\:\-(X|\#)' => 'lipsrsealed',
 		 '\:\-S' => 'huh');
     my $iconpath=$Apache::lonnet::perlvar{'lonIconsURL'};
-    foreach (keys %smileys) {
-	$expression=~s/$_/\<img src="$iconpath\/$smileys{$_}.gif" \/\>/gs; 
+    foreach my $smiley (keys(%smileys)) {
+	$expression=~s/$smiley/\<img src="$iconpath\/$smileys{$smiley}.gif" \/\>/gs; 
     }
     return $expression;
 }
@@ -274,27 +279,34 @@ sub msgtexconverted {
     &init_tth();
     my $outmessage='';
     my $tex=0;
-    foreach (split(/(?:\&lt\;|\<)\/*m\s*(?:\&gt\;|\>)/i,$message)) {
+    foreach my $fragment (split(/(?:\&lt\;|\<)\/*m\s*(?:\&gt\;|\>)/i,$message)) {
 	if ($tex) {
 	    if ($email) {
-		$outmessage.='</pre><tt>'.&to_convert($_).'</tt><pre>'; $tex=0;
+		$outmessage.='</pre><tt>'.&to_convert($fragment).'</tt><pre>';
+		$tex=0;
 	    } else {
-		$outmessage.=&to_convert($_); $tex=0;
+		$outmessage.=&to_convert($fragment);
+		$tex=0;
 	    }
 	} else {
-            $outmessage.=&smiley($_); $tex=1;
+            $outmessage.=&smiley($fragment);
+	    $tex=1;
 	}
     }
     $message=$outmessage; $outmessage=''; $tex=0;
-    foreach (split(/(?:\&lt\;|\<)\/*algebra\s*(?:\&gt\;|\>)/i,$message)) {
+    foreach my $fragment (split(/(?:\&lt\;|\<)\/*algebra\s*(?:\&gt\;|\>)/i,
+				$message)) {
 	if ($tex) {
 	    if ($email) {
-		$outmessage.='</pre><tt>'.&algebra($_,'web').'</tt><pre>'; $tex=0;
+		$outmessage.='</pre><tt>'.&algebra($fragment,'web').'</tt><pre>';
+		$tex=0;
 	    } else {
-		$outmessage.=&algebra($_,'web'); $tex=0;
+		$outmessage.=&algebra($fragment,'web');
+		$tex=0;
 	    }
 	} else {
-            $outmessage.=$_; $tex=1;
+            $outmessage.=$fragment;
+	    $tex=1;
 	}
     }
     if (wantarray) {
@@ -348,9 +360,6 @@ sub postprocess_algebra {
     # moodle had these and I don't know why, ignoring them for now
     # $string =~s/\\fun/ /g;
 
-    # remove the extra () in the denominator of a \frac
-    $string =~s/\\frac{(.+?)}{\\left\((.+?)\\right\)}/\\frac{$1}{$2}/gs;
-    
     # sqrt(3,4) means the 4 root of 3
     $string =~s/\\sqrt{([^,]+),([^\}]+)}/\\sqrt[$2]{$1}/gs;