Maybe 
/http:\S*[^\w\s]/g and s/\G\n//;

[download]
would be good enough? If they cross multiple line boundaries, you'd need to keep a flag, like: 
/http:\S*[^\w\s]/g and s/\G\n// and $http=1;
$http and /^\S*[\w\s]/g and s/\G\n// or $http=0;

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But a lot of URLs end in slashes, and it would be perfectly reasonable to see (in mail): 
Check out
http://homestarrunner.com/sbemail/
and let me know what you think

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and the processor would join the "and" line onto the end of the URL.

Update: Oops, forgot the /g modifier on the pattern matches, so the \G didn't work.

The PerlMonk tr/// Advocate

In reply to Re: Regex to detect and remove a linebreak in an URL by Roy Johnson
in thread Regex to detect and remove a linebreak in an URL by Anonymous Monk

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