"special">,</span> <span class="identifier">SI</span><span class="special">::</span><span class="identifier">length</span><span class="special">,</span> <span class="keyword">double</span><span class="special">,</span> <span class="number">0.3048</span><span class="special">);</span>
</pre>
<p>
        Since the SI unit of length is the meter, these two definitions are equivalent.
        If these conversions have been defined, then converting between scaled forms
        of these units will also automatica