The inside-out braces are really freaky. Also, your solution won't work for multiple input files, while this will: 
perl -i.bak -nlwe '$h{$_}++; if (eof) {print for sort { length($a) <=>
+ length($b) } keys %h;  %h=();}' junk.txt junk2.txt

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Update: D'oh! I knew to do that! Thanks, Merlyn.
The PerlMonk tr/// Advocate

In reply to Re: Using -i in oneliner with postprocessing by Roy Johnson
in thread Using -i in oneliner with postprocessing by Anomynous Monk

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