span class="keyword">int</span><span class="special">,</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span><span class="special">&gt;</span>
<span class="special">&gt;</span> <span class="identifier">token_type</span><span class="special">;</span>
</pre>
<p>
          </p>
<p>
            To avoid the token to have a token value at all, the special tag <code class="computeroutput"><span class="identifier">omit</span></code> can be used: <code class=