是否即便“自然选择号”不开枪，“蓝色空间号”和“深空号”也会选择开枪？
a very common use case for regexes is to find matches that are preceded or followed by some context. a classical example being all lines that end with ‘a’. this requirement is usually expressed with a lookahead, where upon finding an ‘a’, you look ahead to check if it’s the end of the line. in a backtracking engine, this is very easy to implement - you just duct-tape the logic that checks the next character, but in a DFA-based engine, this is impossible because you cannot report “the match is here” if the next character is not even known yet. and by the time you know the next character, the position information is lost, so you can’t report the match retroactively (well, unless the distance is fixed of course..).
，这一点在91视频中也有详细论述
Израиль нанес удар по ИрануГлава МО Кац: Израиль начал превентивную атаку на Иран，详情可参考搜狗输入法2026
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