How do I replace multiple newlines with a single one with Perl's Regular Expressions?

Posted by Simon A. Eugster on Stack Overflow See other posts from Stack Overflow or by Simon A. Eugster
Published on 2010-05-27T19:04:53Z Indexed on 2010/05/27 19:11 UTC
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regex

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perl

I've got a document containing empty lines (\n\n). They can be removed with sed:

echo $'a\n\nb'|sed -e '/^$/d'

But how do I do that with an ordinary regular expression in perl? Anything like the following just shows no result at all.

echo $'a\n\nb'|perl -p -e 's/\n\n/\n/s'

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