{{#each [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] as number}} 
	{{#if threshold >= number}}
		<div transition:foo>{{number}}</div>
	{{/if}}
{{/each}}

<script>
	export default {
		transitions: {
			foo: function ( node ) {
				return {
					duration: 100,
					tick: t => {
						node.foo = t;
					}
				};
			}
		}
	};
</script>