This project separates subdomains, domains, and top-level-domains from URLs in Haskell.
At compile-time, it parses a list of top-level-domains from data/tld.dat.
This list comes from http://mxr.mozilla.org/mozilla/source/netwerk/dns/src/effective_tld_names.dat?raw=1.
This package most likely isn't perfect, especially when handling unicode characters.
You can manually update the TLD list by running the following:
wget http://mxr.mozilla.org/mozilla/source/netwerk/dns/src/effective_tld_names.dat?raw=1 -O data/tld.dat
./process.py
cabal install