如何为两个正则表达式的“交集”编写正则表达式,可用于匹配字符

我还没有找到解决方案,会再看一下.

回答第2部分

这是一个适用于正则表达式引擎的解决方案,允许在后台进行反向引用,例如.NET和Matthew Barnett用于Python的优秀正则表达式模块.

对于你的例子：

(?x)
(?=(12345|abc))(?=(123|abcde)) # AND the expressions
(?: # take the longest match
1(?<=2.*) #abcde,1 is abc
|
2(?<=1.*) #12345,2 is 123
)

一般来说：

(?x)
(?=(expr1))(?=(expr2)) # AND the expressions
(?: # take the longest match
1(?<=2.*) 
|
2(?<=1.*) 
)

我认为这有效……但也许有一个我没有想过的边缘情况.

这是一些经过测试的Python代码.

import regex
pattern = r'''(?x)
(?=(12345|abc))(?=(123|abcde)) # AND the expressions
(?: # take the longest match
1(?<=2.*) #abcde,2 is 123
)
'''
myregex = regex.compile(pattern)

print ("--- blah12345blahabcdeblah ---")
for match in myregex.finditer("blah12345blahabcdeblah"):
    print("Overall match: ",match.group(0))

print ("--- blah123blahabcblah ---")
for match in myregex.finditer("blah123blahabcblah"):
    print("Overall match: ",match.group(0))

print ("--- blah12345blahabcdeblah12345 ---")
for match in myregex.finditer("blah12345blahabcdeblah12378"):
    print("Overall match: ",match.group(0))