<set> and <append>

["Ray Denenberg, Library of Congress" <rden@loc.gov>]

My first question on the description document is the difference between <set> and <append>.

 

<set name=”items”>
 <xpath select=”//mods”/>
 </set>
"Should the response document have contained ten MODS records, then after after the response has been parsed the “items” variable will contain ten values, each value being a single MODS record."

 

This is essentially telling the client that it can extract mods records from a response via the supplied xpath. 

 

 

What does this tell the client:

 

<append name=”items”>
 <xpath select=”//mods”/>
 </set>

 

Thanks.

 

--Ray