How to get the length of an array

[Red-Asuka]

In the old version of i18n, the t method can directly access array. I often use it like this:

          <p
            v-for="(item, index) in $t('index.banner.summary')"
            :key="index"
            :class="[{ 'mb-6': $t('index.banner.summary').length === index + 1 }]"
          >
            {{ item }}
          </p>

But after i18n v9, I need to use tm and rt to access arrays. When I need to access the length of a number, it needs to be written like this:

          <p
            v-for="(item, index) in $tm('index.banner.summary')"
            :key="index"
            :class="[{ 'mb-6': ($tm('index.banner.summary') as LocaleMessageValue<VueMessageType>).length === index + 1 }]"
          >
            {{ $rt(item) }}
          </p>

What is the best way to handle this kind of situation? Any help would be greatly appreciated.