I was surprised to see that you could get "keys" for a scalar.

Then I RTFM, and found:

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.
So - I would continue to code your last line as: 
say "\t$_ => $inner->{$_}" for sort keys %$inner;

[download]
Which, to me, is safer and saner.

             "I'm fairly sure if they took porn off the Internet, there'd only be one website left, and it'd be called 'Bring Back the Porn!'"
        -- Dr. Cox, Scrubs

In reply to Re^2: hash of hashes by NetWallah
in thread hash of hashes by Anonymous Monk

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