fier">system</span><span class="special">::</span><span class="identifier">error_code</span> <span class="special">&amp;</span><span class="special">)</span><span class="special">;</span>
  <span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> T<span class="special">&gt;</span> <span class="identifier">T</span> <span class="special">&amp;</span> <a class="link" href="smart_library.html#idp28625904-bb"><span class="identifier">get_variable</span></a><span