深度遍历implode函数

//Recursive implode
function r_implode($glue,$arr) {
	foreach($arr as $r_arr) {
		if(is_array($r_arr)) {
			$val[] = r_implode($glue,$r_arr);
		}else{
			$val[] = $r_arr;
		}
	}
	return implode($glue,$val);

}