Also, why are you using string-eval, when the plain eval works just as well.

#!/usr/bin/perl  -w
use strict;
use feature ':5.10';

package MyPackage;
{
    BEGIN {
        sub package_vars {
            foreach(@_) {
                eval sub $_ {
                    my \$p = shift;
                    \$p->{$_} = \$_[0] if \@_;
                    \$p->{$_};
                };
            }
        }
    }

    
package_vars( qw(one two three) );
    sub new {
        my $package=shift;
        my $parms=$_[0];
        
        my $this={};

        foreach(%$parms) {
            $this->{$_}=$parms->{$_};
        }

        bless $this, $package;
    }
}

package main;

my $p=new MyPackage({three => 3,});

$p->two(1);

printf "two=%d, three=%d\n",$p->two, $p->three;
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