Or more concisely:
my $p = \\%hash;
$p = \$$p->{$_} for @cats;
$$p->{_val} = $value;

[download]

See Re: Autovivification trick. The form:
$p = \$$p->{$_} ...

[download]

does not leave around refs to empty hashes (it leaves undef's instead).

But seriously, use Data::Diver.

In reply to Re^2: Building an arbitrary-depth, multi-level hash by repellent
in thread Building an arbitrary-depth, multi-level hash by Anonymous Monk

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