This one involves a bit of magic, but it does not use eval, nor does it explicitly list the four operators. 

use Math::BigFloat; $big = Math::BigFloat->bzero; 
$Problem = "12 - 5"; 
$Problem =~ /^(\d+)\s(\S)\s(\d+)$/; ($Number1, $Operator, $Number2) = 
+($1, $2, $3); 
$Answer = ($big + $Number1)->${\("(" . $Operator)}($Number2); 
print $Answer, "\n";

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In reply to Re: '+' to + by ambrus
in thread '+' to + by NateTut

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