function toggleAnonymous(cb) { toggleComments(cb, "p.authorAnonymous"); }
function toggleAttributed(cb) { toggleComments(cb, "p.authorAttributed"); }
function togglePriority(cb) { toggleComments(cb, "p.authorPriority"); }

function toggleComments(cb, clazz) {
  $$(clazz).each( function(c) { if (cb.checked) c.show(); else c.hide(); } );
}