在我的Python应用程序中,我需要编写一个匹配C++ for或while循环的正则表达式,该循环使用分号(;).例如,它应匹配此:
for (int i = 0; i < 10; i++);
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......但不是这个:
for (int i = 0; i < 10; i++)
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这看起来很琐事,直到您意识到开括号和右括号之间的文本可能包含其他括号,例如:
for (int i = funcA(); i < funcB(); i++);
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我正在使用python.re模块.现在我的正则表达式看起来像这样(我已经留下了我的评论,所以你可以更容易理解):
# match any line that begins with a "for" or "while" statement:
^\s*(for|while)\s*
\( # match the initial opening parenthesis
# Now make a named group 'balanced' which matches a balanced substring.
(?P<balanced>
# A balanced substring is either something that is not …Run Code Online (Sandbox Code Playgroud) 我正在尝试使用正则表达式来解析带括号的逻辑表达式
例如:
((weight gt 10) OR (weight lt 100)) AND (length lt 50)
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我希望它可以解析为:
Group 1: (weight gt 10) OR (weight lt 100)
Group 2: AND
Group 3: length lt 50
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如果这个顺序改变:
(length lt 50) AND ((weight gt 10) OR (weight lt 100))
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我希望它可以解析为:
Group 1: length lt 50
Group 2: AND
Group 3: (weight gt 10) OR (weight lt 100)
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我试过的成本最高的是这个表达式:
(\((?>[^()]+|(?1))*\))
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问题在于它仅部分起作用:
((weight gt 10) OR (weight lt 100)) AND (length lt 50)
Group 1: ((weight gt 10) …Run Code Online (Sandbox Code Playgroud)