list all hooked wordpress function

This code originally create by rarst

function list_hooked_functions($tag=false){
        global $wp_filter;
        if ($tag) {
            $hook[$tag]=$wp_filter[$tag];
            if (!is_array($hook[$tag])) {
                trigger_error("Nothing found for '$tag' hook", E_USER_WARNING);
                return;
            }
        } else {
            $hook=$wp_filter;
            ksort($hook);
        }
        echo '<pre>';
        foreach($hook as $tag => $priority){
            echo "<br />>>>>>\t<strong>$tag</strong><br />";
            ksort($priority);
            foreach($priority as $priority => $function){
                echo $priority;
                foreach($function as $name => $properties) echo "\t$name<br />";
            }
        }
        echo '</pre>';
        return;
    }