In the above posting, notice how the mere mention of a hash-key causes it to magically appear, with the initial value of zero, so that it can be "++" incremented to the value of one. This bit of perl-mojo is called "autovivification." Otherwise known as "do the right thing quietly and with a minimum of fuss."

No , that is not autovivification . Just like this is not autovivification 

$foo++;
$bar[$_]++;

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In reply to Re^2: Occurence List by Anonymous Monk
in thread Occurence List by Hopfi

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