这个问题纯粹是为了好玩。正则表达式是否强大到足以将任意两个正整数相加？我的意思是用 a+b 的数值替换字符串 a+b 。
我意识到这取决于我们为数字选择的表示法。当然，如果我们将它们写为计数标记，则正则表达式很容易，只需删除加号即可。用二进制写的数字怎么样？有什么办法可以做到这一点，或者有令人信服的理由来解释为什么这是不可能的吗？
This question is purely for fun. Are regular expressions powerful enough to actually add any two positive integers? By that I mean replacing the string a+b with the numerical value of a+b.
I realize this depends on the notation we choose for numbers. Certainly if we write them as tally marks the regex is easy, just remove the plus symbol. How about numbers written in binary? Any way to do it, or convincing reasons why it is impossible?
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因为这是为了好玩并了解正则表达式的力量：
使用正则表达式查找素数 - http://www.noulakaz.net/weblog/2007/03/18/a-regular-expression-to-check-for-prime-numbers/
Since this is for fun and to see power of regex:
Find prime numbers using regex - http://www.noulakaz.net/weblog/2007/03/18/a-regular-expression-to-check-for-prime-numbers/
如果我们谈论基本的，我会说不，因为正则表达式语言不是图灵完备的，可能具有强大的扩展（例如递归替换或类似工具）。
I would say no if we're talking about basic ones, since regex language is not Turing complete, maybe with powerful exsensions (eg recursive substitutions or similar tools)..