使用正则表达式在Python中的两个字符串之间通过

Question

I want to parse all of the functions inside of a .txt file. It looks like this:

def
  test
end

def
  hello
end

def
  world
end

So, I would get the following returned: [test, hello, world]

Here is what I have tried, but I do not get anything back:

    r = re.findall('def(.*?)end', doc)
    print r

Answer 1

You have to use the re.DOTALL flag which will allow . to match newlines too (since your doc is multi-line).

You could additionally use '^def' and '^end' in the regex if you only wanted the outer def/end blocks (ie ignore indented ones), in which case you would also need to use the re.MULTILINE flag, which allows '^' and '$' to match start/end of line (as opposed to start/end of string ).

re.findall('^def(.*?)^end',doc,re.DOTALL|re.MULTILINE)

Answer 2

r = re.findall('def(.*?)end', doc, re.S)

Answer 3

You need to enable re.MULTILINE flag to match multiple lines in a single regular expression. Also, ^ and $ do NOT match linefeeds ( \\n )

>>> re.findall(r"^def$\n(.*)\n^end$", doc, re.MULTILINE)
['  test', '  hello', '  world']

If you don't want to match the whitespace in the beginning of the blocks, add \\W+ :

>>> re.findall(r"^def$\n\W*(.*)\n^end$", text, re.MULTILINE)
['test', 'hello', 'world']