to be in any special form; they just have to be compile-time <code>Comparable</code>. For example, it is common to provide "names" that are <code><a class="el" href="structboost_1_1hana_1_1string.html" title="Compile-time string. ">hana::string</a></code>s representing the actual names of the members, but one could provide <code><a class="el" href="structboost_1_1hana_1_1integral__constant.html" title="Compile-time value of an integral type. ">hana::integral_constant</a></code>s just as well. The values mus