I wonder if there is any method as simple as if(x==y && i>j) in spry region.
I can't find any information in spry docs (labs.adobe.com/technologies/spry/)

Here is my dirty solution
HTML Code:
<div spry:region="ds1" spry:repeatchildren="ds1">
<b spry:if=" '{title}'!='' ">
<!-- this is the first if --> 
<a href="#"  spry:if=" '{author}'!='' ">{author}
<!-- this is the second if -->
</a>
 </b> </div>