The rust implementation uses #addresses but I find #lookup a bit more intuitive and descriptive.
add ? methods to for simple currency selection: Openalias.addresses('donate@getmonero.org').find(&:xmr?)
Openalias.org is great! There is openalias.rs (written in Rust) to lookup and parse OpenAlias data. This is a ruby wrapper around that rust library. I don't know what I am doing so use at your own risk..and with care.