use 5.012;
use Devel::Peek;

package Bingo {
    use Moo;
    use overload '""' => sub { +shift->ohai };
    has ohai =>
        is => "rw";
};

my $bingo = Bingo->new( ohai => "DER" );

Dump $bingo;
say "\n$bingo\n";
Dump $bingo;