Python正则表达式匹配多行（re.DOTALL）

Question

我试图用多行解析一个字符串。

假设它是：

text = '''
Section1
stuff belonging to section1
stuff belonging to section1
stuff belonging to section1
Section2
stuff belonging to section2
stuff belonging to section2
stuff belonging to section2
'''

我想使用re模块的finditer方法来获取如下字典：

{'section': 'Section1', 'section_data': 'stuff belonging to section1\nstuff belonging to section1\nstuff belonging to section1\n'}
{'section': 'Section2', 'section_data': 'stuff belonging to section2\nstuff belonging to section2\nstuff belonging to section2\n'}

我尝试了以下内容：

import re
re_sections=re.compile(r"(?P<section>Section\d)\s*(?P<section_data>.+)", re.DOTALL)
sections_it = re_sections.finditer(text)

for m in sections_it:
    print m.groupdict() 

但结果是：

{'section': 'Section1', 'section_data': 'stuff belonging to section1\nstuff belonging to    section1\nstuff belonging to section1\nSection2\nstuff belonging to section2\nstuff belonging to section2\nstuff belonging to section2\n'}

因此section_data也匹配Section2。

我还试图告诉第二组除了第一组以外的所有组合。但这导致根本没有输出。

re_sections=re.compile(r"(?P<section>Section\d)\s+(?P<section_data>^(?P=section))", re.DOTALL)

我知道我可以使用以下内容，但我正在寻找一个版本，我不必告诉第二组是什么样的。

re_sections=re.compile(r"(?P<section>Section\d)\s+(?P<section_data>[a-z12\s]+)", re.DOTALL)

非常感谢！

Answer 1

使用预测来匹配的所有内容下一部分标题或字符串的结尾：

re_sections=re.compile(r"(?P<section>Section\d)\s*(?P<section_data>.+?)(?=(?:Section\d|$))", re.DOTALL)

请注意，这也需要非贪婪的.+?，否则它仍然会一直匹配到最后。

演示：

>>> re_sections=re.compile(r"(?P<section>Section\d)\s*(?P<section_data>.+?)(?=(?:Section\d|$))", re.DOTALL)
>>> for m in re_sections.finditer(text): print m.groupdict()
... 
{'section': 'Section1', 'section_data': 'stuff belonging to section1\nstuff belonging to section1\nstuff belonging to section1\n'}
{'section': 'Section2', 'section_data': 'stuff belonging to section2\nstuff belonging to section2\nstuff belonging to section2'}