Within the code that you omitted: 
    unless ( $holes ) {
        #
        # create the holes
        #
                ...
    }

[download]
you call holes::new and insert it into @$holes? Is it possible for $obj->{'holes'} to return a reference to undef?

Nothing else suggests itself at the moment.

We're not really tightening our belts, it just feels that way because we're getting fatter.

In reply to Re^3: Can't call method "foo" on unblessed reference by Roy Johnson
in thread Can't call method "foo" on unblessed reference by Plankton

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