data-inttrie package is a simple lazy, infinite trie for integers. It is now available in Fedora. Install it using:

 $ sudo yum install ghc-data-inttrie-devel

To import the data-inttrie module, use:

Prelude> :m + Data.IntTrie

The Bits class in Data.Bits module defines bitwise operations on integral types, and is defined using:

class Num a => Bits a where

The complement function, for example, reverses the bits in the argument:

Prelude> :m + Data.bits
Prelude Data.Bits> complement 3

The apply function in Data.IntTrie applies a trie to an argument:

apply :: (Ord b, Bits b) => IntTrie a -> b -> a

For example:

Prelude Data.IntTrie> let bits f = apply (fmap f identity)
Prelude Data.IntTrie> bits (*3) 4 :: Int