$HOHOH{'Alphakey2'}->{'Betakey2'} ||= {}; will initialize with a new (empty) hashref if there's not already an existing key at that level (although keep in mind that that will also populate $HOHOH{'Alphakey2'} with a new hashref as well if it doesn't exist; search for "autovivification" for more details, and go read perlreftut and perlref as well until it becomes clear).

The cake is a lie.
The cake is a lie.
The cake is a lie.

In reply to Re^3: Problems with HOHOH modification by Fletch
in thread Problems with HOHOH modification by tamaguchi

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