r our <code class="computeroutput"><span class="identifier">annotate_position</span></code>
        on_success handler to have access to:
      </p>
<pre class="programlisting"><span class="keyword">auto</span> <span class="keyword">const</span> <span class="identifier">parser</span> <span class="special">=</span>
    <span class="comment">// we pass our position_cache to the parser so we can access</span>
    <span class="comment">// it later in our on_sucess handlers</span>
    <span class="identifier">wi