code class="computeroutput"><span class="identifier">namespace0</span><span class="special">::</span><span class="identifier">namespace1</span><span class="special">::...</span>
        <span class="identifier">struct_name</span></code>. If an empty namespace
        sequence is given (that is a macro that expands to nothing), the struct is
        placed in the global namespace. The sequence of <code class="computeroutput"><span class="special">(</span><span class="identifier">member_typeN</span><span clas