http://www.perlmonks.org?node_id=997687


in reply to Re^2: How do you find keys of a Blessed Hash?
in thread How do you find keys of a Blessed Hash?

Instead of running off, again, on a wild goose chase, it maybe would be simpler to just read keys, the official documentation? It mentions there that:

Starting with Perl 5.14, keys can take a scalar EXPR, which must contain a reference to an unblessed hash or array. The argument will be dereferenced automatically. This aspect of keys is considered highly experimental. The exact behaviour may change in a future version of Perl.

... and without seeing your code, my guess is that you are "using" that experimental feature, knowingly or not.