-<%perl>
-my $url_base_base= 'http://yarrg.chiark.net/download/jpctb';
-my $download_version= 'test';
-my $url_base= "$url_base_base/$download_version";
-</%perl>
+<%shared>
+my $url_base_base= 'http://yarrg.chiark.net/download/jarrg';
+</%shared>
+<%def downloadurl><%args>
+$leaf
+$test => 0
+# ^ change this to change the default version
+</%args><%perl>
+my $download_version= $test ? '/test' : '';
+my $url_base= "$url_base_base$download_version";
+my $url= $url_base.'/'.$leaf;
+</%perl><a href="<% $url %>"><%
+ $m->has_content ? $m->content : $url
+%></a></%def>