Hey, that's was pretty slick. crazysniffable, if you're not sure what's going on, here's the scoop:

The map operator takes an array and loops over each element. In this case, the array is the keys of %hash. In srawls' code for map, he's asking for it to return the keys to the anonymous hash at $hash{$_}. Since he's evaluating it in scalar context, it returns the total number of elements, instead of the keys. This code is equivalent to:

my $numSubKeys = 0;
foreach ( keys %hash ) {
    $numSubKeys += scalar keys %{$hash{$_}} };
}
[download]

Of course, as srawls mentioned, it loops. There's really no way around this (that I can see).

Cheers,
Ovid

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