rkdown">
      <p>Constructs a regular expression.</p>
<p>Throws a <a href="../../dart-core/FormatException-class.html">FormatException</a> if <code>source</code> is not valid regular
expression syntax.</p>
<p>If <code>multiLine</code> is enabled, then <code>^</code> and <code>$</code> will match the beginning and
end of a <em>line</em>, in addition to matching beginning and end of input,
respectively.</p>
<p>If <code>caseSensitive</code> is disabled, then case is ignored.</p>
<p>If <code>unicode</code> is 