use Safe;
$compartment = new Safe('userMath');
$result = $compartment->reval($expressionToEval);

##</code><code>##

$compartment->permit(qw(sqrt));

##</code><code>##

$compartment->share_from('Math::Complex', [ '&make' ]);

##</code><code>##

$compartment->reval('use Math::Complex');