Treetop/PEG 中的非贪婪匹配？
我将如何在 Treetop 中做这样的事情？
/.+?;/
似乎唯一的方法是：
[^;]+ ';'
这有点丑……还有其他方法吗？ .+? 似乎不起作用..
How would I do something like this in Treetop?
/.+?;/
It seems like the only way is to do:
[^;]+ ';'
Which is kind of ugly.. any other way? .+? doesn't seem to work..
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默认情况下，PEG 是贪婪和盲目的，这意味着它们会吃掉尽可能多的输入，并且不考虑之后会发生什么：
S <- P1* P2（贪婪、盲目）这可能相当大通过使用有序选择（并且不使用前瞻）可以轻松修复：
S <- P1 S / P2（贪婪，非盲）S <- P2 / P1 S（懒惰，非盲目）PEGs are greedy and blind by default, that means they eat as much input as they can and they do not consider what comes afterwards:
S <- P1* P2(greedy, blind)That can be considerably easy fixed though by making use of the ordered choice (and without using lookaheads):
S <- P1 S / P2(greedy, non-blind)S <- P2 / P1 S(lazy, non-blind)嗯，我知道 PEG 是贪婪的，而且没有办法绕过它。 不过，可以使用前瞻来模仿这种行为，例如
!(';' .)Well, I learnt PEGs are greedy, and there's no way around it. Lookaheads can be used to mimic this behavior though, like
!(';' .)我不知道 Treetop，但是
/[^;]+;/可以工作吗？通过快速搜索，我看到建议 Treetop 不执行贪婪或惰性（非贪婪）量词，并且
+实际上是一个所有格量词（由++ 其他正则表达式风格）。如果是这种情况，我不确定除了否定类之外，您还有其他基于正则表达式的选项。
I don't know Treetop, but would
/[^;]+;/work?From a quick search, I saw suggestion that Treetop doesn't do greedy nor lazy (non-greedy) quantifiers, and that the
+is actually a possessive quantifier (represented by++in other regex flavours).If this is the case, I'm not sure you've got any other regex-based options than the negated class.