新手问下这条正则什么意思？
$str = preg_replace("/\{pc:(\w+)\s+([^}]+)\}/ie", "self::pc_tag('$1','$2', '$0')", $str);
$1 $2 代表前面的2个子模式， 那么$0代表什么。。。
------解决方案--------------------
$0代表 整个模式
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