To set it, you need to just do the same thing except that at each step instead of keeping the hash element, you keep a reference to it:
$entryref = \$hash; $entryref = \$$entryref->{$_} for @a; $$entryref = 1;
Note that this will create hashrefs at any undefined levels, even the top one.
I'm sorry but that doesn't work as is on my system: "Not a HASH reference at x.pl line 9.".
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| |/ \| Alexandre (Midnite) Jousset |
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