ay only choose a single
            type: field name, field values, and the body container will all use the
            same string type. This limits utility of the customization point. The
            library's use of the string trait is limited to selecting between <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span></code> and <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><spa