Parsing a tweet to extract hashtags into an array

Question

I am having a heck of a time taking the information in a tweet including hashtags, and pulling each hashtag into an array using Python. I am embarrassed to even put what I

Answer 1

AndiDogs answer will screw up with links and other stuff, you may want to filter them out first. After that use this code:

UTF_CHARS = ur'a-z0-9_\u00c0-\u00d6\u00d8-\u00f6\u00f8-\u00ff'
TAG_EXP = ur'(^|[^0-9A-Z&/]+)(#|\uff03)([0-9A-Z_]*[A-Z_]+[%s]*)' % UTF_CHARS
TAG_REGEX = re.compile(TAG_EXP, re.UNICODE | re.IGNORECASE)

It may seem overkill but this has been converted from here http://github.com/mzsanford/twitter-text-java. It will handle like 99% of all hashtags in the same way that twitter handles them.

For more converted twitter regex check out this: http://github.com/BonsaiDen/Atarashii/blob/master/atarashii/usr/share/pyshared/atarashii/formatter.py

EDIT:
Check out: http://github.com/BonsaiDen/AtarashiiFormat

Answer 2

A simple regex should do the job:

>>> import re
>>> s = "I love #stackoverflow because #people are very #helpful!"
>>> re.findall(r"#(\w+)", s)
['stackoverflow', 'people', 'helpful']

Note though, that as suggested in other answers, this may also find non-hashtags, such as a hash location in a URL:

>>> re.findall(r"#(\w+)", "http://example.org/#comments")
['comments']

So another simple solution would be the following (removes duplicates as a bonus):

>>> def extract_hash_tags(s):
...    return set(part[1:] for part in s.split() if part.startswith('#'))
...
>>> extract_hash_tags("#test http://example.org/#comments #test")
set(['test'])

Answer 3

hashtags = [word for word in tweet.split() if word[0] == "#"]