title: regex for only lowercase letters and underscore
body: <p>I'm trying to validate a field called &quot;role&quot; where the pattern's type is only names like this: super_user, computer_group. But not this: &quot;admin_area_&quot; or &quot;Admin_area??&quot;, &quot;ADMIN_&quot;.
  Only lowercase letters and underscore between those letters, never on final. This is what i tried until now:</p>
  <p><code>/^[a-z]+(_*[a-z]+)*$/</code> and <code>/^[a-z_]*$/</code></p>
  <p>But for some reason, when the user types &quot;??&quot; or any other character my validation is still allowing those characters.</p>
  <p><em><strong>NOTE:</strong></em> my inputs are from quasar framework where I validate that in <code>:rules</code></p>