Regular expression matching a multiline block of text

by

Try this:

re.compile(r"^(.+)\n((?:\n.+)+)", re.MULTILINE)

I think your biggest problem is that you’re expecting the ^ and $ anchors to match linefeeds, but they don’t. In multiline mode, ^ matches the position immediately following a newline and $ matches the position immediately preceding a newline.

Be aware, too, that a newline can consist of a linefeed (\n), a carriage-return (\r), or a carriage-return+linefeed (\r\n). If you aren’t certain that your target text uses only linefeeds, you should use this more inclusive version of the regex:

re.compile(r"^(.+)(?:\n|\r\n?)((?:(?:\n|\r\n?).+)+)", re.MULTILINE)

BTW, you don’t want to use the DOTALL modifier here; you’re relying on the fact that the dot matches everything except newlines.

More Related Contents:

  1. Searching for IP addresses in a file
  2. How to understand regular expression with python?
  3. Escaping regex string
  4. Fast punctuation removal with pandas
  5. Python regex matching Unicode properties
  6. Python: How to match nested parentheses with regex?
  7. How do you validate a URL with a regular expression in Python?
  8. Match text between two strings with regular expression
  9. Regex to extract URLs from href attribute in HTML with Python [duplicate]
  10. How to replace only part of the match with python re.sub
  11. How to split by commas that are not within parentheses?
  12. Replace first occurrence of string in Python
  13. In Python, how to check if a string only contains certain characters?
  14. How to handle response encoding from urllib.request.urlopen() , to avoid TypeError: can’t use a string pattern on a bytes-like object
  15. Regex: AttributeError: ‘NoneType’ object has no attribute ‘groups’
  16. remove unicode emoji using re in python
  17. Python – RegEx for splitting text into sentences (sentence-tokenizing) [duplicate]
  18. Is there a way to put comments in multiline code?
  19. Python regex string matching?
  20. How to use regular expression in lxml xpath?
  21. replacing only single instances of a character with python regexp
  22. Why isn’t the regular expression’s “non-capturing” group working?
  23. Python Regular Expression Match All 5 Digit Numbers but None Larger
  24. Remove Sub String by using Python
  25. Type of compiled regex object in python
  26. How does python and the regex module handle backslashes?
  27. Extracting matches with the original case used in the pattern during a case insensitive search
  28. re.findall which returns a dict of named capturing groups?
  29. Why doesn’t ignorecase flag (re.I) work in re.sub() [duplicate]
  30. Perl compatible regular expression (PCRE) in Python

Leave a Comment