This was a great idea for a game of Golf. Recent outings have been too much like mini CS projects. Sorry Masem. ;-)

This uses your methodology. There are 69 chars in the body of the program. It passes -w and strict. It also handle negative numbers:

perl -le'/^\D$/?($_.=pop@_)&&push@_,eval pop(@_).$_:push@_,$_ for@ARGV
+;print@_'
[download]

I recently spent two months of my spare time implementing a type of RPN parser using Parse::RecDescent. Obviously I was taking the wrong approach. :-)

John.
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