I'm creating a widget with items (enable items). Each item has 1 links to  a post.  I'd like to print the post-ID of that post. How can you achieve that in twig?

Can anybody give me some direction how to achieve this?

No I'm using a link. Can't use a post  list because I need some extra attributes on it. (like the hotspot x and y coordinates).

(https://unlimited-elements.helpscoutdocs.com/article/81-php-integration-get-data-from-php)

I just figured out from the documentation that you can call any PHP function with

{{ do_action('some_action','param1','param2','param3') }}

So now I'm  doing this..

{{ do_action( 'url_to_postid', 'item.link' ) }}

This wordpress function should return the postid from the slug. But no luck :( Any idea what's going wrong)?

Ok.. what I learned and what works is this:

I added a custom filter in my function.php

add_filter( 'getID', 'get_my_id' );
function get_my_id( $myslug ) { 
    $postid = url_to_postid( $myslug );
    return $postid;
}

In the html field (twig template) I'm doing this:

{% set itemID = apply_filters('getID', item.link|raw ) %}
{{ itemID }}

This way I get the ID of the linked post. :)