为什么基于文本的正则发动机无法处理懒惰的量词？
我遇到过很多次，基于文本的正则发动机无法支持懒惰量词。但是我找不到原因。但是我知道，他们在内部使用DFA，并且没有回溯。
然后我坐下来为懒惰的量词绘制DFA，这就是我得到的。\/\*。*\*\/（其中*是懒惰）（正确匹配C注释）：
（ regex form dfa下方的dfa 以确保其表现如前所述）
进行比较，我还写了贪婪的量词版本。\/\*。*\*\*\/（其中*是贪婪的）（不正确匹配C注释）：
（ regex form dfa以下以确保其表现如前所述）
对不起，我忘了在图中添加启动状态。将最左侧的状态视为两者的开始。
在这里，贪婪的版本实际上需要备份！此外，DFA可以完成懒惰的量词。我做错了吗？为什么有很多说基于文本的正则发动机不支持懒惰？
ps：为了保持简单，我没有完成以上两个DFA。要完成它们，只需添加从每个状态到新的错误状态的所有不存在的移动即可。一旦进入错误状态，就不会退出。
I have came across many times that, text-based regex engines cannot support lazy quantifiers. But I could not find why. But I came to know that, they internally use DFAs, and they do not backtrack.
Then I sat down to draw a DFA for lazy quantifiers and this is what I got.\/\*.*\*\/(where * is lazy)(matches C comments correctly):
(regex form of below DFA to make sure it is behaving as expected)
For comparison, I also wrote the greedy quantifier version.\/\*.*\*\/(where * is greedy)(matches C comments incorrectly):
(regex form of below DFA to make sure it is behaving as expected)
Sorry, I forgot to add start state in the diagram. Consider left-most state as start in both of them.
Here, greedy version actually requires backing-up! Also, lazy quantifiers can be done with DFA. Did I did anything wrong? Why are there many saying text-based regex engines don't support lazy?
PS: To keep it simple, I did not complete both of the above DFAs. To complete them, just add all the non-existent moves from every state to a new error state. Once entered error state, no exiting from it.
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