svelte/test/runtime/samples/binding-indirect-computed/main.html

<select bind:value="selected.letter">
	{#each uppercase as letter}
		<option value="{letter}">{letter}</option>
	{/each}
</select>

{selected.letter}

<script>
	export default {
		data() {
			return {
				letters: [
					'a',
					'b',
					'c'
				],
				selected: {
					letter: ''
				}
			}
		},
		computed:{
			uppercase: ({ letters }) => letters.map(x => x.toUpperCase())
		}
	};
</script>