keyword">typename</span> Combiner<span class="special">&gt;</span> 
    <a class="link" href="map.html" title="Class template map">map</a><span class="special">&lt;</span> <span class="identifier">DomainT</span><span class="special">,</span> <span class="identifier">CodomainT</span><span class="special">,</span> <span class="identifier">Traits</span><span class="special">,</span> <span class="identifier">Compare</span><span class="special">,</span> <span class="identifier">Combine</span><span class="special