Perl allocates a number of buckets per hash. Whenever a certain percentage of the buckets are filled with hash keys, the number of buckets gets doubled. Because of the hash algorithm a key then either stays in its bucket or has to go to the corresponding bucket of the new space.

When you print a hash in scalar context, it tells you how many buckets it has and how many are filled. Try this:

perl -e ' for $i (1..100) {$h{$e++}=1; print scalar(%h),"\n" }'

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Note that not every key entry occupies a new bucket. That is the case when two different keys produce the same hash number and therefore occupy the same bucket.

In reply to Re: strange keys with a hash by jethro
in thread strange keys with a hash by chuckd

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