I generally prefer less nesting, and thus direct return. However your example suffers from code duplication for the version that uses return(), though that's not necessary: 
sub err {
    { status => 0, error => shift(@_), external_id => undef);

}
sub foo
{
   my($self) = @_;

   my $authentication = $self->authenticate_user();
   return err('Authentication Failed') unless defined $authentication;

   my $profile = $self->get_user_profile();
   return err('User is not active') unless $profile->is_active;

   my($external_id) = $self->find_external_id($profile);
   if(! defined($external_id)){
        $external_id = $self->send_profile_to_partner($profile);
   }
   return {status=>1, error=>undef, external_id=>$external_id};
}

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In reply to Re: Control Flow - Multiple returns or nested conditionals by moritz
in thread Control Flow - Multiple returns or nested conditionals by JediWizard

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