span><span class="keyword">typename</span> Engine<span class="special">&gt;</span> 
    <span class="identifier">result_type</span> <a class="link" href="geometric_distribution.html#id-1_3_34_5_6_16_1_1_1_6_8-bb"><span class="keyword">operator</span><span class="special">(</span><span class="special">)</span></a><span class="special">(</span><span class="identifier">Engine</span> <span class="special">&amp;</span><span class="special">,</span> <span class="keyword">const</span> <a class="link" href="geometr