You could use eval() 
my $res = eval "@ARGV";

[download]
But it would be infintely safer if you just parsed the string as an optree and executed it appropriately. If you look around the Monastery you'll find many examples of this sort of situation.
HTH

_________
broquaint

In reply to Re: extract an operator from a string by broquaint
in thread extract an operator from a string by Anonymous Monk

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