使用文本中存在模式的正则表达式拆分字符串

Question

我有很多字符串需要用逗号分隔。示例：

myString = r'test,Test,NEAR(this,that,DISTANCE=4),test again,"another test"'
myString = r'test,Test,FOLLOWEDBY(this,that,DISTANCE=4),test again,"another test"'

我想要的输出是：

["test", "Test", "NEAR(this,that,DISTANCE=4)", "test again", """another test"""] #list length = 5

我不知道如何在一项中保留“this,that,DISTANCE”之间的逗号。我试过这个：

l = re.compile(r',').split(myString) # matches all commas
l = re.compile(r'(?<!\(),(?=\))').split(myString) # (negative lookback/lookforward) - no matches at all

有什么想法吗？假设允许的“函数”列表定义为：

f = ["NEAR","FOLLOWEDBY","AND","OR","MAX"]

Answer 1

你可以使用

(?:\([^()]*\)|[^,])+

见the regex demo。

(?:\([^()]*\)|[^,])+ 模式匹配括号之间的任何子字符串的一次或多次出现，其中没有( 和) 或除, 之外的任何字符。

见Python demo：

import re
rx = r"(?:\([^()]*\)|[^,])+"
s = 'test,Test,NEAR(this,that,DISTANCE=4),test again,"another test"'
print(re.findall(rx, s))
# => ['test', 'Test', 'NEAR(this,that,DISTANCE=4)', 'test again', '"another test"']

Answer 2

如果要明确指定哪些字符串算作函数，则需要动态构建正则表达式。否则，请使用 Wiktor 的解决方案。

>>> functions = ["NEAR","FOLLOWEDBY","AND","OR","MAX"]
>>> funcs = '|'.join('{}\([^\)]+\)'.format(f) for f in functions)
>>> regex = '({})|,'.format(funcs)
>>>
>>> myString1 = 'test,Test,NEAR(this,that,DISTANCE=4),test again,"another test"'
>>> list(filter(None, re.split(regex, myString1)))
['test', 'Test', 'NEAR(this,that,DISTANCE=4)', 'test again', '"another test"']
>>> myString2 = 'test,Test,FOLLOWEDBY(this,that,DISTANCE=4),test again,"another test"'
>>> list(filter(None, re.split(regex, myString2)))
['test',
 'Test',
 'FOLLOWEDBY(this,that,DISTANCE=4)',
 'test again',
 '"another test"']