using-items.php

<?php

$list = new MyListContainingClass();

$list->add("stuff", "more", "yeah", "woo");

$list->remove("more", "yeah");

variadic.php

<?php

class MyListContainingClass {
    /** @var string[] */
    private $list = [];
    
    //other stuff...
    
    public function add(string ...$items)
    {
        $this->list = array_merge($this->list, $items);
    }
    
    public function remove(string ...$items)
    {
        $this->list = array_diff($this->list, $items);
    }
    
    //other stuff...
}