package KeyAtom;
use Moose;
use Moose::Util::TypeConstraints;
subtype 'typeKeyAtom',
    as 'Str | RegexpRef';

has 'data' => (
    is      => 'rw',
    isa     => 'typeKeyAtom',
);

package ValAtom;
use Moose;
use Moose::Util::TypeConstraints;

extends 'KeyAtom';

subtype 'typeValAtom',
    as 'typeKeyAtom | ArrayRef | HashRef';

#has 'data' => (   #oh my...
has '+data' => (
    is      => 'rw',            #re declare
    isa     => 'typeValAtom',
);

no Moose;

###test
package main;
use Data::Dumper;
my $test= ValAtom->new();
for ("test str", qr("^test"), [qw/a b c/], {a=>'b',b=>'c'}, sub{'test'
+} ){
    $test->data($_);
    print Dumper $test->data;
}
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