Unless you're wedded to making the attribute lazy, you could build it in the BUILD method:

use v5.14;

package Part {
    use Moose;
    has foo  => (is => 'ro');
    has bar  => (is => 'ro');
}

package Whole {
    use Moose;
    has baz  => (is => 'ro');
    has part => (
        is       => 'ro',
        writer   => '_set_part',
        init_arg => 0,
        isa      => 'Part',
        handles  => qr/.*/,
    );
    
    sub BUILD {
        my $self = shift;
        $self->_set_part(Part->new(@_));
    }
}

my $obj = Whole->new(foo => 1, bar => 2, baz => 3);

print $obj->dump;

say for $obj->foo, $obj->bar, $obj->baz;

[download]
use Moops; class Cow :rw { has name => (default => 'Ermintrude') }; say Cow->new->name

In reply to Re: [Moose] Critique request on my Moose design (anti?)pattern by tobyink
in thread [Moose] Critique request on my Moose design (anti?)pattern by three18ti

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