How to apply a "without" filter in a plugin
You can use similar logic that Craft uses for the withoutFilter in CraftTwigExtension.

public function withoutFilter($arr, $exclude)
{
    $filteredArray = array();

    if (!is_array($exclude))
    {
        $exclude = array($exclude);
    }

    foreach ($arr as $key =&gt; $value)
    {
        if (!in_array($value, $exclude))
        {
            $filteredArray[$key] = $value;
        }
    }

    return $filteredArray;
}