I have to agree with CountZero. There be dragons there. I stopped using string evals because they always find a way to come back and bite me. There are times when using a string eval is necessary, but it's not here. Here's a script that I did using Eval::WithLexicals.

#!/usr/bin/perl 

use autodie;
use strictures 1;
use Eval::WithLexicals;
use Data::Dumper::Concise;

my($x) = Eval::WithLexicals->new();
my $y = 3;
my $z = 5;

use strict 'refs';
eval {
    $x = $y + $z;    
    return;
};
    
print Dumper($x);
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