Function 1:

Depending on the blog-URL I define multiple variables (i.e. customer-group IDs).

Some of the varaibles are integers and some are arrays.

Function I – blog URL:

The variables change, depending on the blog URL. Function could look like this:

add_action( 'after_setup_theme', 'my_site_url' );
    function my_site_url(){
        $site_url = get_bloginfo('wpurl');
        
        $stage_url = 'https://los.examplos.mx';
        
        if ($site_url == $stage_url) {
            
            /* - customer group ids for use in functions */
            $wiederverkaeufer = 1234;
            
            /* Versteckte Kategorien */
            $hidecategory_wvk = [24, 863, 51, 87];

            $return_array = [$wiederverkaeufer, $hidecategory_wvk];
            
        } else {
            
            /* - customer group ids for use in functions */
            
            $wiederverkaeufer = 5678;
            
            /* Versteckte Kategorien */
            $hidecategory_wvk = [51, 48, 42];

            $return_array = [$wiederverkaeufer, $hidecategory_wvk];

        }
      return $return_array;
    }

Function II

Now I want to access those variables with some of the other functions within my functions.php. (This worked with constants before). For example

add_action( 'woocommerce_before_calculate_totals', 'cart_shipping_class_message', 20, 1 );
    function cart_items_shipping_class_message( $cart ){

    $my_ids = my_site_url();
    $my_ids[0] = $wiederverkaeufer;
        
    // Customer group current user 
    $group_id = BM_Conditionals::get_validated_customer_group();
    
    // if is group "wiederverkaeufer" return 
    if ( $wiederverkaeufer == $group_id )
        return;

    //Do something
}

Function III: Test function:

I built a little test-function to check if I can call multiple variables and arrays from one function.

 function my_shop_meldung(){
     
     $a = "Moin";
     $b = "Servus";
     $c = "Hallo";
     $d = ["22", "44", "55"];
     
    $return_array = [$a, $b, $c, $d];
     
     return $return_array; 
 }
 
 
 function add_custom_text() {
    ?>
    <div id="my_shopmeldung">
    <?php
        
        $my_results = my_shop_meldung();
        $a = $my_results[0];
        $b = $my_results[1]; 
        $c = $my_results[2];
        $d = $my_results[3][1];
        
        //echo $a . $b . $c . $d;
        echo $d;
        
    ?>
    </div>
    <?php
}
add_action('kt_beforeheader', 'add_custom_text', 10, 0);

I think this works as I could see the output “44” from the array.

Before I go on from here: is this a good method if I want to use multiple variables within different functions depending on my blog-URL? I don’t want to use globals and constants don’t seem to work anymore in PHP-8 like they did in 7.2.