traditionally I would do:

sub new {
 my $classs = shift;
 my $self = { foo => $_[0] }; # initiate the fooneff
 bless $self, $class;
}
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the problem you ran into is several fold.

1. your $self is the class being passed in
2. you then convert it into a hash_ref
3. you then bless an empty hash and retreat into an old dog

Your work around is somewhat ingenous, since you re-use the $self in a creative way. But unless you really have a good reason to want to have a 'reference' passed in to your new() as an instance method, you really should avoid it.