python - 有没有办法在进行正则表达式匹配时使用出现次数的范围？

Question

给定一个字符串 aaabbb 是否有一种方法可以编写正则表达式来查找子字符串的数量，例如 ab、aabb、aaabbb。

我是通过构造正则表达式 [a]{m}[b]{m} 并迭代一系列值来实现的。但我想知道是否有办法一次性完成。

Answer 1

如评论中所述，^(?:a(?=a*(\1?+b)))+\1$ 允许使用广泛的正则表达式功能匹配此类平衡构造.

Demo

完整解释 here .

也就是说，如果你想列出所有匹配平衡结构的重叠子串，你可以使用 (?=((?:a(?=a*(\2?+b)))+\2 )):

(?=                         # Using a lookahead allows to restart matching even if a match has already been found, as a lookaround doesn't "consume" its content.
  (                         # Using a capturing group allows to retrieve the match.
    (?:a(?=a*(\2?+b)))+\2)  # As an outer capturing group has been defined, thus numbered 1, we rewrite the inner part using the proper group 2.
  )
)

Demo