 assertion with TRUTH at other index TERM.<br /><code></code>If TRUTH is nil, all assertions are mapped.<br /><code></code>If GAFS-ONLY, then only gafs are mapped.<br />FUNCTION must satisfy FUNCTION-SPEC-P.<br />Single value returned satisfies NULL. <br /><br /><a name="FN-DEF-GATHER-INDEX" id="FN-DEF-GATHER-INDEX"></a>function <tt><strong>GATHER-INDEX</strong> : (term &amp;optional remove-duplicates?)</tt><br />Return a list of all mt-relevant assertions indexed via TERM.<br />If REMOVE-DUPLICATES? is 