current match, in addition
        there will be one extra string enumerated when no more matches can be found:
        from the end of the last match found, to the end of the underlying sequence.
      </p>
<p>
        <span class="bold"><strong>Throws</strong></span>: <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">runtime_error</span></code>
        if the complexity of matching the expression against an N character string
        be