Make code snippet into a foreach loop

I have a piece of code which is used to replace double dashes for commas in a wordpress taxonomy called “authors” before displaying values to the end user.

This is working great, but now I need to apply it to several different taxonomies, no just “authors” but also “printers”, “translators”, etc.

My idea was to build an array of taxonomies instead of a single variable and then use a foreach loop to apply the find and replace to each of them, but no matter how I try it I can’t seem to make it work…

Any idea how to make the following code into a foreach loop if $custom_taxonomy_type was an array?

This is the code that is currently working for a single taxonomy.

if(!is_admin()){ // make sure the filters are only called in the frontend

$custom_taxonomy_type = 'authors';  // here goes your taxonomy type

function comma_taxonomy_filter($tag_arr){
    global $custom_taxonomy_type;
    $tag_arr_new = $tag_arr;
    if($tag_arr->taxonomy == $custom_taxonomy_type && strpos($tag_arr->name, '--')){
        $tag_arr_new->name = str_replace('--',', ',$tag_arr->name);
    }
    return $tag_arr_new;    
}
add_filter('get_authors', comma_taxonomy_filter);

function comma_taxonomies_filter($tags_arr){
    $tags_arr_new = array();
    foreach($tags_arr as $tag_arr){
        $tags_arr_new[] = comma_taxonomy_filter($tag_arr);
    }
    return $tags_arr_new;
}
add_filter('get_the_taxonomies',    comma_taxonomies_filter);
add_filter('get_terms',             comma_taxonomies_filter);
add_filter('get_the_terms',         comma_taxonomies_filter);

}

As requested by @Epodax here are the two things I've tried so far. Both result in a blank page:

if(!is_admin()){ // make sure the filters are only called in the frontend

    $custom_taxonomy_type_array = array('authors', 'printer');  // here goes your taxonomy type

    foreach ($custom_taxonomy_type_array as $custom_taxonomy_type) {
        function comma_taxonomy_filter($tag_arr){
            global $custom_taxonomy_type;
            $tag_arr_new = $tag_arr;
            if($tag_arr->taxonomy == $custom_taxonomy_type && strpos($tag_arr->name, '--')){
                $tag_arr_new->name = str_replace('--',', ',$tag_arr->name);
            }
            return $tag_arr_new;    
        }
        add_filter('get_'.$custom_taxonomy_type, comma_taxonomy_filter);

        function comma_taxonomies_filter($tags_arr){
            $tags_arr_new = array();
            foreach($tags_arr as $tag_arr){
                $tags_arr_new[] = comma_taxonomy_filter($tag_arr);
            }
            return $tags_arr_new;
        }
        add_filter('get_the_taxonomies',    comma_taxonomies_filter);
        add_filter('get_terms',             comma_taxonomies_filter);
        add_filter('get_the_terms',         comma_taxonomies_filter);
    }


}

and

if(!is_admin()){ // make sure the filters are only called in the frontend

    $custom_taxonomy_type_array = array('authors', 'printer');  // here goes your taxonomy type

    function comma_taxonomy_filter($tag_arr){
        foreach ($custom_taxonomy_type_array as $custom_taxonomy_type) {
            global $custom_taxonomy_type;
            $tag_arr_new = $tag_arr;
            if($tag_arr->taxonomy == $custom_taxonomy_type && strpos($tag_arr->name, '--')){
                $tag_arr_new->name = str_replace('--',', ',$tag_arr->name);
            }
            return $tag_arr_new;    
        }
    }
    foreach ($custom_taxonomy_type_array as $custom_taxonomy_type) {
        add_filter('get_'.$custom_taxonomy_type, comma_taxonomy_filter);
    }

    function comma_taxonomies_filter($tags_arr){
        foreach ($custom_taxonomy_type_array as $custom_taxonomy_type) {
            $tags_arr_new = array();
            foreach($tags_arr as $tag_arr){
                $tags_arr_new[] = comma_taxonomy_filter($tag_arr);
            }
            return $tags_arr_new;
        }
    }
    foreach ($custom_taxonomy_type_array as $custom_taxonomy_type) {
        add_filter('get_the_taxonomies',    comma_taxonomies_filter);
        add_filter('get_terms',             comma_taxonomies_filter);
        add_filter('get_the_terms',         comma_taxonomies_filter);
    }

}

via Chebli Mohamed