Svelte execute function when any of group of variables changes

In Svelte RealWord App there is something like this:

$: query && getData();

This calls REST API when page size or other query parameters change.

I have similar situation for listing entities and do:

 $: activePage && sort && pageSize && getData();

This all works well (although the && is a strange construct to say I want to execute getData() when activePage, sort or pageSize changes.

With this approach problem arises when you want to also include variable which is evaluates to Falsy.

Example, add searchQuery text:

let searchQuery = "";$: searchQuery && activePage && sort && pageSize && getData();

Now reactivity does not work since searchQuery evaluates to false.

We can do this:

$: activePage && sort && pageSize && getData();$: searchQuery, getData();

But with this getData() gets called 2 times.

Does anybody know of better approach for this?