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in reply to Re: On zero-width negative lookahead assertions
in thread On zero-width negative lookahead assertions

perl -ne '/^root:\s*/ and $_ !~ /admin\@somewhere\.here/ and print' alias

That's ok, but I want to understand that blah-blah-look-ahead thing

perl -ne '/^root:(?!\s*admin\@somewhere\.here)/ and print' alias

This works! But I can't understand why it doesn't work if you put the \s* outside the parens, nor I can understand why it stops working if I put the \s*$ at the end of the regex :-(

Thanks a lot

Ciao!
--bronto


In theory, there is no difference between theory and practice. In practice, there is.