I just don't really conceptually get why the first iteration works but after that I get a shallow copy.

You never get a copy of the array referenced by $data2, not even the first time through the loop. Every time through the loop you set $r->{sizes} to be a reference to the same original anonymous array. If you want a new array you have to create it. util has shown you several ways you can make a copy of the array referenced by $data2. Having created a copy of the original array, you can then set $r->{sizes} to be a reference to the copy.

In reply to Re^5: Strange hash array behavior by ig
in thread Strange hash array behavior by Rodster001

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