.</p>
<p>Of course, the library can still be used without requiring global function
objects for those who prefer to avoid them will still find the library useful.</p>
</div>
<div class="section" id="projections">
<h2>Projections<a class="headerlink" href="#projections" title="Permalink to this headline">¶</a></h2>
<p>Instead of writing the projection multiple times in algorithms:</p>
<div class="highlight-cpp"><div class="highlight"><pre><span></span><span class="n">std</span><span class="o">::</span><span