Maybe you can show us what is in $json_decoded and $key1 and $json_decoded->{$key1}?

The syntax that will work on all versions of Perl is keys %{ $json_decoded->{$key1} }, provided that $json_decoded is a hash reference.

I note that your usage of $key2 is inconsistent with its name - you're using it as array index, not as a hash key:

for my $key3 (keys $json_decoded->{$key1}[$key2])

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This is a change allowed since Perl 5.12, but I find it somewhat confusing still.

I guess the best approach is to reduce your data structure and code to a short, self-contained example that still exhibits the problem and then to post that together with the Perl versions and their output.

In reply to Re: keys in reference experimental or reference is deprecated by Corion
in thread keys in reference experimental or reference is deprecated by demichi

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