What is tripping me up is that I have no immediate idea what $$r{$k} is doing

It's the same thing as $r->{$k}; personally I sometimes prefer this style because it's a little bit shorter and my $r = {a=>1}; print $$r{a}; is very similar to my %r = (a=>1); print $r{a};. However, what usually trips people up is that this only works as long as the expression really is that simple (e.g. more complex values than $r), in which case the arrow dereferencing is the cleaner way to go.

In reply to Re^2: Tidy up json from nulls, empty arrays and hashes by haukex
in thread Tidy up json from nulls, empty arrays and hashes by leszekdubiel

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