Now that I've actually tested the code, I have a bugfix for it: 
perl -pe 'goto LINE unless /\S/; s/\n/,/ if ($a = 1 - $a)'

[download]
This fix keeps the structure of the original code, only changing the next to a goto. 

--
integral, resident of freenode's #perl

In reply to Re: Merge pairs of lines by integral
in thread Merge pairs of lines by integral

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