The four-line version _was_ needlessly verbose. But I don't think getting it down to one line is necessary. Two lines may be about right for this example.

Good code is terse enough that it doesn't take forever to say anything, but not so terse that it makes the reader shake his head and drag out reference books. Somewhere in between ten-thousand-line epics and golfed-down one-liners there's a happy medium.

Of course, you may not need the @ipaddr array at all; if you're only using the resulting numbers once, you may be able to feed the results of the second line directly into the next function. I'd have to see the larger context of your code to see how to further simplify it. But I don't think that combining your existing two lines into one will make for greater simplicity.

If you really want to learn serious code *shortening* techniques, do a Google search for "Perl golf". But be advised that shorter code isn't always easier to read. Up to a point it is, but Perl golf has a strong tendency to go beyond that point. If you just want to scare your coworker, show him some of the stuff from the obfuscation section of Perlmonks, and tell him you're studying programming techniques from the people who wrote them.

$;=sub{$/};@;=map{my($a,$b)=($_,$;);$;=sub{$a.$b->()}}
split//,".rekcah lreP rehtona tsuJ";$\=$ ;->();print$/
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