regex for Twitter username

(?<=^|(?<=[^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 @ whats.up@example.com @shahmirj

Matches:

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

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

Twitter recently released to open source in various languages including Java, Ruby (gem) and Javascript implementations of the code they use for finding user names, hash tags, lists and urls.

It is very regular expression oriented.

This is a method I have used in a project that takes the text attribute of a tweet object and returns the text with both the hashtags and user_mentions linked to their appropriate pages on twitter, complying with the most recent twitter display guidelines

def link_tweet(tweet):
"""
This method takes the text attribute from a tweet object and returns it with
user_mentions and hashtags linked
"""
tweet = re.sub(r'(\A|\s)@(\w+)', r'\1@<a href="http://www.twitter.com/\2">\2</a>', str(tweet))
return re.sub(r'(\A|\s)#(\w+)', r'\1#<a href="http://search.twitter.com/search?q=%23\2">\2</a>', str(tweet))

Once you call this method you can pass in the param my_tweet[x].text. Hope this is helpful.

Shorter, /@([\w]+)/ works fine.