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* 原文照发。 结果是不同于我所认为的。
原标题:python regular-expression "`(``|[^`])*`" ,The result is different from what I thought
  • 时间:2023-09-06 02:24:18
  •  标签:
  • python

enter image description here I found that StackOverflow has changed my issue, please check the image

我在使用固定的表达方式时遇到了问题。

import re
a_re = r"`(``|[^`])*`"
a_str =  `abc`12`cde`45 
b = re.findall(a_re,a_str)
print(b) # [ c ,  e ]

为什么出现这种结果?

我再次尝试其他规则。

import re
a_re = r"`(ab|[^c])*`"
a_str =  `ab`1`df` 
b = re.findall(a_re,a_str)
print(b) # [ f ]

更令人困惑

问题回答

https://docs.python.org/3/library/re.html#re.findall”rel=“nofollow noreferer” www.un.org/Depts/DGACM/index_french.htm

其结果取决于该模式中捕获组的数量。 如果没有团体,则回到一个与整个模式相匹配的护卫清单。 如果只有一个组,则回到一个组群对应的座标清单。

捕获组的最终价值是last,在总配对中加以比对,例如,<代码>(“>][>][>][>][>][>][>]∗ 匹配, 之后是(`[> >]>>。

re.findall’s API is badly designed; I recommend you use alternative functions, like re.finditer, instead.

import re
a_re = r"`((``|[^`])*)`"
a_str =  `abc`12`cde`45 
b = [m.group(1).replace("``", "`") for m in re.finditer(a_re, a_str)]
print(b)  # [ abc ,  cde ]

你的回归表达是错误的,请使用另一种倒退表达方式。 你们想要什么? 我恳请你摘录 a和de,然后请你使用以下文字:

a_re = r"`([^`]*)`"

也就是说,你想要在“......”内恢复任何争执,当然你可以尝试

a_re = r"([^`]*)"
[  ,  abc ,   ,  12 ,   ,  cde ,   ,  45 ,   ]

 a_re = r"`[^`]*`"

[ `abc` ,  `cde` ]




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