al><b>&gt;</b></span>
    <span class=special>&gt;,</span>
    <span class=comment>// unique index on phone number</span>
    <span class=identifier>ordered_unique</span><span class=special>&lt;</span><span class=identifier>key</span><span class=special>&lt;&amp;</span><span class=identifier>phonebook_entry</span><span class=special>::</span><span class=identifier>phone_number</span><span class=special>&gt;&gt;</span>
  <span class=special>&gt;</span>
<span class=special>&gt;</span> <span class=identifier>p