. also, you want the 'm' modifier for the s/// operator, since the whole file is read into a scalar

Which is not true with -pe without an alternative line ending. The file is read line-by-line.

the original poster wanted to keep those lines

So you're doing the exact opposite. I'm sure that'll help. Sigh. How about: 

perl -i -pe'$_ = "" unless /^--/ or !/\S/'

[download]
which does what the original poster wants (If I understood correctly).

Update - This was meant to be a reply to the parent of the node I replied to. This node's parent didn't have the code indented in a way I recognised as being a quote, and I didn't view the message in its context when I replied. To everyone who cites: please use <blockquote>. I use <p><blockquote><em> quote </em></blockquote></p><p> answer </p>, and even have that in my signature for ease of use. 

- Yes, I reinvent wheels.
- Spam: Visit eurotraQ.

In reply to Re: Re: Re: simple (in theory) regexp question by Juerd
in thread simple (in theory) regexp question by Anonymous Monk

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