Re: Hash of Hash of Hash of ...

[tlm]

Check out this snippet by merlyn.

[simonm]

There are also several pre-written implementations of this on CPAN. My Data::DRef module has functions to get and set values based on multiple-key lists like you're working with:

 
  use Data::DRef qw( set_value_for_keys );
  set_value_for_keys( \%big_hoh, $data, @key_list );