That is fixable though with a lookahead: 
s/([^\n])\n(?!\n)/$1/g;

[download]
Or the probably faster lookbehind: 
s/(?<!\n)\n([^\n])/$1/g;

[download]

UPDATE
chipmunk noticed a typo. I had not closed the second match. Oops.

In reply to Re (tilly) 3: Regex Question by tilly
in thread Regex Question by madhatter

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