Describe the problem

<script>
export let bar;

function foo(node, bar) {
	bar = 123;

	return {
		update(bar) {},
		destroy() {},
	};
}
</script>

<div use:foo={bar}>
	{bar}
</div>

Currently this prints undefined. This makes recreating bind:group much harder.

Describe the proposed solution

Allow svelte/actions to update passed variables.

Alternatives considered

The passed object could be a reference.

Importance

would make my life easier