span class="identifier">spirit</span><span class="special">::</span><span class="identifier">qi</span><span class="special">::</span><span class="identifier">rule</span><span class="special">&lt;</span><span class="identifier">Iterator</span><span class="special">,</span> <span class="identifier">Skipper</span><span class="special">&gt;</span> <span class="identifier">file</span><span class="special">,</span> <span class="identifier">line</span><span class="special">,</span> <span class="identifier">command