#!/usr/bin/perl
use warnings;
use strict;
use feature qw{ say };

{   package MyObj;

    use overload
      '""'     => \&both,
      fallback => 1;

    sub new {
        my ($class, $first, $last) = @_;
        bless { first => $first, last => $last }, $class
    }

    sub first {
        $_[0]->{first}
    }

    sub both {
        "@{ $_[0] }{qw{first last}}"
    }
}

sub makeupname {
    'MyObj'->new(qw(John Smith));
}

say makeupname();
say makeupname()->first;