Modulo is a Radiant extension that adds tags for conditional rendering of child pages based on their ordinal values. For example, it can render different markup for odd or even children:
<r:children:each>
<r:if_odd>
<div class="left">
</r:if_odd>
<r:if_even>
<div class="right">
</r:if_even>
<r:content part="body" />
</div>
</r:children:each>
Modulo introduces the following new Radius tags:
<r:if_even><r:unless_even><r:if_odd><r:unless_odd>