ExpressionEngine Stash match/against example

gistfile1.html

{!-- get a list of people with last names starting A-F --}
{exp:channel:entries channel="people" sort="asc" orderby="person_lname"}    
    {exp:stash:append name="people_a_f" match="#^[A-F]#" against="{person_lname}"}
        <li><a href="/people/{entry_url}" title="view profile">{title}</a></li>
    {/exp:stash:append}
{/exp:channel:entries}