This was a gimme from my earlier post. It's also fairly readable. Compared to yours, the expression is 1 char shorter, and there's one fewer command-line option. 
perl -pe  'eof||y/\n/,/'

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In reply to Re: * Re: perl 1-liner to join a list? by Roy Johnson
in thread perl 1-liner to join a list? by bfdi533

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