s/([^\n])\n([^\n])/$1$2/g;
That fails on fred\nX\nY\nbarney, since the X will be sucked up while fixing the preceding newline, and won't be available to match for the following newline.

Be very wary when matching right-side context. Passing it through to the "already seen" category means it won't be able to be left-side context for a later match.

-- Randal L. Schwartz, Perl hacker

In reply to Re: Re: Regex Question by merlyn
in thread Regex Question by madhatter

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