phplib的嵌套block问题

Question

<?
    include("./include/template.inc");
    $t =new Template(".");
    $t->set_file ("fHandle","1.tpl");
    $t->set_block ("fHandle","col","cols");
    $t->set_block ("fHandle","row","rows");    for ($i=1;$i<5;$i++)
    {
        for ($j=1;$j<5;$j++)
        {
            $num=$i*$j;
            $code=$i.'*'.$j.'='.$num;
            $t->set_var ("NUM","$code");
            $t->parse ("cols","row",true);
        }
        $t->parse ("rows","row",true);
    }
    $t->parse ("out","fHandle");
    $t->p("out");
?>