Another approach and not really a direct answer to your question:
perhaps you like to use bbcode or something similar. Then you could offer your users something like 
 
Have a look at [url]http://www.perlmonks.org[/url] an write to [email]
+joe@localhost[/email]

[download]
to format their posts. You could try BBCode::Parser. I haven tried it, but it sounds promising.

k

In reply to Re: detecting URLs and turning them into links by klekker
in thread detecting URLs and turning them into links by keiusui

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
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