class="identifier">double_</span> <span class="special">&gt;&gt;</span> <span class="identifier">double_</span>
</pre>
<p>
        is compatible with any fusion sequence holding two types, where both types
        have to be compatible with <code class="computeroutput"><span class="keyword">double</span></code>.
        The first element of the fusion sequence has to be compatible with the attribute
        of the first <code class="computeroutput"><span class="identifier">double_</span></code>, and
       