Template variables are not expanded inside filters.
:javascript
$("\##{id}").hide();
translated to
<script type="text/javascript">
//<![CDATA[
$(function() {
$("\##{id}").hide();
});
//]]>
</script>
Workaround for JavaScript filter is using script tag instead:
script(type="text/javascript")
$("\##{id}").hide();