title: Multiple Or Conditions in Regex
body: <p>Lets say I have messy data pattern:</p>
  <ul>
  <li>TRND-0LL2134.SV</li>
  <li>TRN_RTXDFT.SV</li>
  <li>TRND_ZRSFTFF.SV</li>
  <li>DR3345.SV</li>
  </ul>
  <p>I am trying to use regex to filter on prefixes with &quot;-&quot; or &quot;_&quot;, and those without.</p>
  <p>Desired output</p>
  <pre><code>column1     column2     column3
  =========== =========== ===========
  TRND        -           0LL2134.SV
  TRN         _           RTXDFT.SV
  TRND        _           ZRSFTFF.SV
  &lt;blank&gt;     &lt;blank&gt;     DR3345.SV
  </code></pre>
  <p>So far I used</p>
  <pre><code>\-|\_
  </code></pre>
  <p>to filter on prefixes with &quot;-&quot; or &quot;<em>&quot; but have a challenge filtering on strings that do not have a prefix with either &quot;-&quot; or &quot;</em>&quot;</p>