head><tr>
<th align="left">Symbol</th>
<th align="left">Description</th>
</tr></thead>
<tbody>
<tr>
<td align="left"><code class="computeroutput">no_action</code></td>
<td align="left">successful operation - no action action required</td>
</tr>
<tr>
<td align="left"><code class="computeroutput">uninitialized_value</code></td>
<td align="left">report attempt to use an uninitialized value - not
            currently used</td>
</tr>
<tr>
<td align="left"><code class="computeroutput">arithmetic_error</code></td