auto-vivification - PerlDoc is your friend.

Essentially, it's the fact that Perl will quietly create a space for something if you refer to it. Example: 

my %x;

$x{foo} = 'bar';

[download]

In that example, the memory for $x{foo} is auto-vivified. Contrast that with C++ and you'll see the benefit.

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We are the carpenters and bricklayers of the Information Age.

The idea is a little like C++ templates, except not quite so brain-meltingly complicated. -- TheDamian, Exegesis 6

... strings and arrays will suffice. As they are easily available as native data types in any sane language, ... - blokhead, speaking on evolutionary algorithms

Please remember that I'm crufty and crochety. All opinions are purely mine and all code is untested, unless otherwise specified.

In reply to Re3: Data structure for this... by dragonchild
in thread Data structure for this... by robinbowes

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