regex for Twitter username

Question

Could you provide a regex that match Twitter usernames?

Extra bonus if a Python example is provided.

Answer 1

(?<=^|(?<=[^a-zA-Z0-9-_\.]))@([A-Za-z]+[A-Za-z0-9-_]+) 

I've used this as it disregards emails.

Here is a sample tweet:

@Hello how are @you doing @my_friend, email @000 me @ [email protected] @shahmirj

Matches:

• @Hello
• @you
• @my_friend
• @shahmirj

It will also work for hashtags, I use the same expression with the @ changed to #.

Answer 2

If you're talking about the @username thing they use on twitter, then you can use this:

import re twitter_username_re = re.compile(r'@([A-Za-z0-9_]+)') 

To make every instance an HTML link, you could do something like this:

my_html_str = twitter_username_re.sub(lambda m: '<a href="http://twitter.com/%s">%s</a>' % (m.group(1), m.group(0)), my_tweet)