Blog of Leonid Mamchenkov

There are several very useful modules at CPAN to work with Perl hashes. Here is a short list to get you started.

• Tie::Hash::Approx - use key approximation to find values.
• Tie::AliasHash - use multiple keys for a single value.
• Tie::Hash::Expire - expire keys in hash after a predefined period of time.
• Bloom::Filter, Bloom16, Text::Bloom - implementation of Bloom’s filter algorithm. If you want to know more about Bloom’s algorithm, read here.
• Tie::Hash::Regex, Tie::RegexpHash - use regular expressions to match hash keys.
• Tie::SortHash, Tie::Hash::Rank, Tie::InsertOrderHash, Tie::Hash::Indexed, Tie::IxHash - sorting hashes by key, by value; keeping hashes sorted, keeping elements in the same order they were inserted, etc.
• Tie::RangeHash - associating values with a range of keys (e.g.: from 1 to 6 is “a”, from 7 to 10 is “b”, etc)

I’ve used this article (in Russian) as a base for this post.