Question about Svelte's reactive statements with typescript

I got the TS2695 error in this code.

<script lang="ts">  let count = 0;  $: count, (() => {    console.log(`TEST: ${count}`);  })();</script>

The error was the below.

Left side of comma operator is unused and has no side effects. ts(2695)

I thought the left side of the comma operator is the count variable, and it is used by console.log().

So, I didn't know how to handle this error. However, the code works well.

Please help me how to fix this error.