How to skip initial reactivity for a variable within svelte components?

I have a simple custom component in Svelte, where I use reactivity to execute some code.

<script lang="ts">
    export let liked: boolean
    $: {
         //..code that should be executed when liked is toggled ...//
    }
</script>

My problem is that when the component first mounts liked is toggled and the code is executed which is not what I want, I want to execute the code only when the user initiate the toggle.

That is why I added this initial variable here, which is making my code work as expected, but was wondering if there is a more idiomatic/clean way to do this?

<script lang="ts">
    export let liked: boolean
    let initial = true
    $: {
        if (!initial) {
            //..code that should be executed when liked is toggled ...//
        } else {
            initial = false
        }
    }
</script>