;</span> <span class="identifier">Dim</span><span class="special">,</span> <span class="identifier">System</span> <span class="special">&gt;</span><span class="special">,</span> <span class="identifier">Y</span><span class="special">&gt;</span> <span class="special">{</span>
  <span class="comment">// types</span>
  <span class="keyword">typedef</span> <a class="link" href="../units/multiply_typeof_helper.html" title="Struct template multiply_typeof_helper">boost::units::multiply_typeof_helper</a><span clas