replace URLs in text with links to URLs

Question

Using Python I want to replace all URLs in a body of text with links to those URLs, like what Gmail does. Can this be done in a one liner regular expression?

Edit: b

Answer 1

Gmail is a lot more open, when it comes to URLs, but it is not always right either. e.g. it will make www.a.b into a hyperlink as well as http://a.b but it often fails because of wrapped text and uncommon (but valid) URL characters.

See appendix A. A. Collected BNF for URI for syntax, and use that to build a reasonable regular expression that will consider what surrounds the URL as well. You'd be well advised to consider a couple of scenarios where URLs might end up.